Mahuna

Frank,
A beautiful model of an interesting subject.  Well done!
A bit of a minor quibble.  I don’t understand the centerboard tackle.  With the pendant led through the two double bolcks both fixed to the cabin roof the mechanical advantage would be lost.  Shouldn’t the pendant be spliced into the end of the forward double block?

Ok, I’ll try to explain.  The centerboard is under tension caused by the weight of the board trying to pivot it about its pivot pin.  We’ll call the tension T.  A rope transmits this tension along its length. By changing the direction of the rope a block or pulley fixed to the boat’s structure changes the direction of T but not it’s magnitude.  As rigged the force required to raise the centerboard is still T.  In fact it is somewhat more than T due to the friction in the pulleys and blocks.
 
Now, attach the block to the pendent so that it can move back and forth as the centerboard pivots up and down.  The force on the end of the block attached to the pendent is still T and while,the TOTAL force on the opposite end of the block must be equal and acting in the opposite direction, it is equally distributed between each of the “legs” of the tackle, in this case Five. The tension in each leg of the tackle including the leg that is secured to the cleat is therefore T/5. We would therefore say that this tackle has a mechanical advantage of 5.
 
There is however no free lunch.  Although the force to lift the board is now 1/5 of what it would have been without the tackle it now requires 5 times the length of pull (length of rope) as before.
 
I hope that all of this makes sense.
 
Roger

Thanks Popeye.  Yeah, the bit of rigging is cool, but it may be wrong (see my reply to Roger).  

Hi Roger:
 
Thanks for the feedback and the comment on the tackle.  I don’t see it as a minor quibble – in fact you raise the same question I originally dealt with.  I originally intended to install the tackle as you described, having seen it in the plans for the Willie Bennett.  I changed my mind based on some other info, and I probably took the wrong approach, since I’m not all that familiar with the mechanics of tackles.  Let me explain why I took the approach that I did:
 
In Chapelle’s book “American Small Sailing Craft” (and in his short pamphlet on Skipjacks) he described how the centerboard would be treated when the boat was pulled out of the water for maintenance. The centerboard would be left in the water, and later (when the maintenance was completed and the boat was back in the water), the centerboard would be brought up into its case using the lanyard and a fore-end line.  It seems to me that the length of travel of the lanyard tackle would be limited to the length of the cabin roof that it sits on, so I had a hard time visualizing this operation.  
 
In addition, the lanyard travels under a pulley normally located on the deck or on the side of the aft hatch, as in the case of the Willie Bennett.  I found the following photo of the Kathryn’s deck pulley for the lanyard in the book “Working Skipjacks of Deal Island”.  
 

 
Since the lanyard runs under the pulley, I saw this as an additional limitation to how far the tackle could move.
 
I was also confused by the length of the coil shown in the HAER photo I included in my post.  It seemed to me that if the lanyard was spliced to the forward block there would be no need for the length of line shown in the coil.
 
Again, I’m not very knowledgeable on the mechanics of these tackles, so I probably was in error.  If you, or other readers, could help me understand how the issues I mention above would be addressed with the alternate tackle arrangement then I probably would re-do the tackle to make it more correct.
 
Thanks again for your feedback – to me, this is the real value of this forum.  Discussions like this are a valuable part of the learning process.
 

Thanks Popeye.  Yeah, the bit of rigging is cool, but it may be wrong (see my reply to Roger).  

Hi Roger:
 
Thanks for the feedback and the comment on the tackle.  I don’t see it as a minor quibble – in fact you raise the same question I originally dealt with.  I originally intended to install the tackle as you described, having seen it in the plans for the Willie Bennett.  I changed my mind based on some other info, and I probably took the wrong approach, since I’m not all that familiar with the mechanics of tackles.  Let me explain why I took the approach that I did:
 
In Chapelle’s book “American Small Sailing Craft” (and in his short pamphlet on Skipjacks) he described how the centerboard would be treated when the boat was pulled out of the water for maintenance. The centerboard would be left in the water, and later (when the maintenance was completed and the boat was back in the water), the centerboard would be brought up into its case using the lanyard and a fore-end line.  It seems to me that the length of travel of the lanyard tackle would be limited to the length of the cabin roof that it sits on, so I had a hard time visualizing this operation.  
 
In addition, the lanyard travels under a pulley normally located on the deck or on the side of the aft hatch, as in the case of the Willie Bennett.  I found the following photo of the Kathryn’s deck pulley for the lanyard in the book “Working Skipjacks of Deal Island”.  
 

 
Since the lanyard runs under the pulley, I saw this as an additional limitation to how far the tackle could move.
 
I was also confused by the length of the coil shown in the HAER photo I included in my post.  It seemed to me that if the lanyard was spliced to the forward block there would be no need for the length of line shown in the coil.
 
Again, I’m not very knowledgeable on the mechanics of these tackles, so I probably was in error.  If you, or other readers, could help me understand how the issues I mention above would be addressed with the alternate tackle arrangement then I probably would re-do the tackle to make it more correct.
 
Thanks again for your feedback – to me, this is the real value of this forum.  Discussions like this are a valuable part of the learning process.
 

Thanks Popeye.  Yeah, the bit of rigging is cool, but it may be wrong (see my reply to Roger).  

Hi Roger:
 
Thanks for the feedback and the comment on the tackle.  I don’t see it as a minor quibble – in fact you raise the same question I originally dealt with.  I originally intended to install the tackle as you described, having seen it in the plans for the Willie Bennett.  I changed my mind based on some other info, and I probably took the wrong approach, since I’m not all that familiar with the mechanics of tackles.  Let me explain why I took the approach that I did:
 
In Chapelle’s book “American Small Sailing Craft” (and in his short pamphlet on Skipjacks) he described how the centerboard would be treated when the boat was pulled out of the water for maintenance. The centerboard would be left in the water, and later (when the maintenance was completed and the boat was back in the water), the centerboard would be brought up into its case using the lanyard and a fore-end line.  It seems to me that the length of travel of the lanyard tackle would be limited to the length of the cabin roof that it sits on, so I had a hard time visualizing this operation.  
 
In addition, the lanyard travels under a pulley normally located on the deck or on the side of the aft hatch, as in the case of the Willie Bennett.  I found the following photo of the Kathryn’s deck pulley for the lanyard in the book “Working Skipjacks of Deal Island”.  
 

 
Since the lanyard runs under the pulley, I saw this as an additional limitation to how far the tackle could move.
 
I was also confused by the length of the coil shown in the HAER photo I included in my post.  It seemed to me that if the lanyard was spliced to the forward block there would be no need for the length of line shown in the coil.
 
Again, I’m not very knowledgeable on the mechanics of these tackles, so I probably was in error.  If you, or other readers, could help me understand how the issues I mention above would be addressed with the alternate tackle arrangement then I probably would re-do the tackle to make it more correct.
 
Thanks again for your feedback – to me, this is the real value of this forum.  Discussions like this are a valuable part of the learning process.
 

Thanks Popeye.  Yeah, the bit of rigging is cool, but it may be wrong (see my reply to Roger).  

Hi Roger:
 
Thanks for the feedback and the comment on the tackle.  I don’t see it as a minor quibble – in fact you raise the same question I originally dealt with.  I originally intended to install the tackle as you described, having seen it in the plans for the Willie Bennett.  I changed my mind based on some other info, and I probably took the wrong approach, since I’m not all that familiar with the mechanics of tackles.  Let me explain why I took the approach that I did:
 
In Chapelle’s book “American Small Sailing Craft” (and in his short pamphlet on Skipjacks) he described how the centerboard would be treated when the boat was pulled out of the water for maintenance. The centerboard would be left in the water, and later (when the maintenance was completed and the boat was back in the water), the centerboard would be brought up into its case using the lanyard and a fore-end line.  It seems to me that the length of travel of the lanyard tackle would be limited to the length of the cabin roof that it sits on, so I had a hard time visualizing this operation.  
 
In addition, the lanyard travels under a pulley normally located on the deck or on the side of the aft hatch, as in the case of the Willie Bennett.  I found the following photo of the Kathryn’s deck pulley for the lanyard in the book “Working Skipjacks of Deal Island”.  
 

 
Since the lanyard runs under the pulley, I saw this as an additional limitation to how far the tackle could move.
 
I was also confused by the length of the coil shown in the HAER photo I included in my post.  It seemed to me that if the lanyard was spliced to the forward block there would be no need for the length of line shown in the coil.
 
Again, I’m not very knowledgeable on the mechanics of these tackles, so I probably was in error.  If you, or other readers, could help me understand how the issues I mention above would be addressed with the alternate tackle arrangement then I probably would re-do the tackle to make it more correct.
 
Thanks again for your feedback – to me, this is the real value of this forum.  Discussions like this are a valuable part of the learning process.
 

Thanks Carl.  We'll find out pretty soon, I hope.

Part 57 – Cabin Exterior Details
 
My original intent was to construct Kathryn’s cabin so that the roof would be removable, allowing the interior of the cabin to be easily seen. After a lot of thought I decided against this for the following reasons:
 
1.    The boom will be very close to the cabin roof, and there would be a real danger of disturbing the boom if the cabin roof was not very carefully moved.
2.    Each cabin door consists of two parts, which allows the doors to be opened for the doghouse while leaving the lower parts closed.  Constructing these doors as two separate parts would make a very delicate part that could be damaged when the roof was removed.
3.    The Centerboard Hauling Lanyard is run over the main roof of the cabin, with pulleys, tackles, and a cleat for securing the lanyard.  Leaving the roof removable would eliminate this interesting detail.
 
The following HAER photo shows some of the detail of the Centerboard Hauling Lanyard.  Also note the controls for the Push Boat just behind the lanyard.
 
                        
 
There are two metal cleats on Kathryn: one that secures the hauling lanyard on the cabin roof, and one that is mounted on top of the bowsprit to secure the jib downhaul.  The other cleats are wooden cleats.
 
The metal cleats for the model were made from 3/64 brass rod and 1/8 x 1/32 brass strip.  The brass rod was flattened on one side using a file.  This would allow the strip to closely mate with the rod.
 
                        
 
A light groove was milled in a piece of Corian to hold the rod so that the strip could be centered on the rod for soldering.
 
                        
 
                        
 
The rod was then cut to the appropriate length with a razor saw. These metal cleats are 8” long (1/4” on the model).
 
                        
 
The strip was narrowed its final width, using a file and a rotary tool.
 
                        
 
The cleat was then ground to its final shape using a rotary tool with diamond cutters, and was polished using emery cloth.  The post for mounting the cleat was also cut into the strip.
 
                        
 
The cleat was then blackened using a well-diluted (5:1) mixture of the JAX Flemish Black, giving a steel-like color.  The following photo shows the jib downhaul cleat in place on the bowsprit.
 
                        
 
There are two open pulleys that service the Centerboard Hauling Lanyard. One is on the deck, with the lanyard running below the sheave.  The other is on the cabin roof, with the lanyard running over the sheave.
 
The sheaves on the model were made from 3/32” brass rod, which would equate to 3” diameter.
 
The rod was bored out for the axle using a center drill followed by a HHS drill.
 
                        
 
The width of the sheave on the model is .020.  A parting tool was used to cut partway through the rod so that this width was set off.  A very small round escapement file was then used to form the groove in the sheave, by carefully filing the shape as the lathe turned at a relatively slow speed.
 
                        
 
The sheave was then parted off using a jewelers saw while the lathe was turned by hand.
 
                        
 
                        
 
A HHS drill bit, reversed in the tailstock, was used to prevent the sheave from coming loose when it was parted (it would probably never be found again if it left of its own accord!).
 
The body of the pulley was made from a 1/16 strip of .010 brass sheet that had been cut using a paper cutter.  The strip was bent around a 1/32” thick piece of brass strip to get the appropriate shape, and was then bent around a sacrificial piece of wood for drilling.
 
                        
 
A mounting post was soldered to the hole drilled at its base.
 
                        
 
The shape of the body was then finished using a rotary tool and a diamond cylinder.
 
                        
 
The sheave was mounted in the body and soldered on one side of the axle. 
 
                        
 
The pulley was then cleaned up using files and emery paper.
 
The Centerboard Hauling Lanyard comes out of the deck under the dredge winder, with a wooden fairlead in place to keep the lanyard from fraying on the edge of the hole in the deck plank.
 
                        
 
The lanyard then runs under a pulley mounted at deck level just forward of the cabin.
 
                        
 
The lanyard then runs over a pulley on the cabin roof, through a double-block tackle, and is tied off to a cleat.
 
                        
 
The cabin doors are fairly plain, and seem to be made mostly from plywood. The hinges on the real Kathryn are piano hinges painted to match the doors, so they are virtually invisible. The outside of the doors have some strips to provide protection from weather for the separation between the upper and lower parts of each door, between the two doors when they are closed. The interior of the doors are plain and flat.
 
I wanted to leave the doors open so at least some of the cabin details could be seen, but I wasn’t thrilled with having plain flat doors being the only thing showing.  In addition, if the doors were fully opened then the rear windows of the doghouse would be blocked.  To resolve these issues I decided to have the doors propped partially open.
 
Thin pieces of wood strip were shaped so that one edge was angled. These strips were glued to the doors at that angled edge and served as a door jam.
 
                        
 
The door jams were glued to the inside of the door frames.
 
                        
 

 
So now the cabin exterior details are completed.  The only thing left on the cabin is to fabricate the column that contains the controls for the Push Boat.  This will probably be the subject of the next post.
 
Cheers everyone!

Thanks Patrick.  Can't wait to see your next build.

Thanks Carl.  We'll find out pretty soon, I hope.

Part 57 – Cabin Exterior Details
 
My original intent was to construct Kathryn’s cabin so that the roof would be removable, allowing the interior of the cabin to be easily seen. After a lot of thought I decided against this for the following reasons:
 
1.    The boom will be very close to the cabin roof, and there would be a real danger of disturbing the boom if the cabin roof was not very carefully moved.
2.    Each cabin door consists of two parts, which allows the doors to be opened for the doghouse while leaving the lower parts closed.  Constructing these doors as two separate parts would make a very delicate part that could be damaged when the roof was removed.
3.    The Centerboard Hauling Lanyard is run over the main roof of the cabin, with pulleys, tackles, and a cleat for securing the lanyard.  Leaving the roof removable would eliminate this interesting detail.
 
The following HAER photo shows some of the detail of the Centerboard Hauling Lanyard.  Also note the controls for the Push Boat just behind the lanyard.
 
                        
 
There are two metal cleats on Kathryn: one that secures the hauling lanyard on the cabin roof, and one that is mounted on top of the bowsprit to secure the jib downhaul.  The other cleats are wooden cleats.
 
The metal cleats for the model were made from 3/64 brass rod and 1/8 x 1/32 brass strip.  The brass rod was flattened on one side using a file.  This would allow the strip to closely mate with the rod.
 
                        
 
A light groove was milled in a piece of Corian to hold the rod so that the strip could be centered on the rod for soldering.
 
                        
 
                        
 
The rod was then cut to the appropriate length with a razor saw. These metal cleats are 8” long (1/4” on the model).
 
                        
 
The strip was narrowed its final width, using a file and a rotary tool.
 
                        
 
The cleat was then ground to its final shape using a rotary tool with diamond cutters, and was polished using emery cloth.  The post for mounting the cleat was also cut into the strip.
 
                        
 
The cleat was then blackened using a well-diluted (5:1) mixture of the JAX Flemish Black, giving a steel-like color.  The following photo shows the jib downhaul cleat in place on the bowsprit.
 
                        
 
There are two open pulleys that service the Centerboard Hauling Lanyard. One is on the deck, with the lanyard running below the sheave.  The other is on the cabin roof, with the lanyard running over the sheave.
 
The sheaves on the model were made from 3/32” brass rod, which would equate to 3” diameter.
 
The rod was bored out for the axle using a center drill followed by a HHS drill.
 
                        
 
The width of the sheave on the model is .020.  A parting tool was used to cut partway through the rod so that this width was set off.  A very small round escapement file was then used to form the groove in the sheave, by carefully filing the shape as the lathe turned at a relatively slow speed.
 
                        
 
The sheave was then parted off using a jewelers saw while the lathe was turned by hand.
 
                        
 
                        
 
A HHS drill bit, reversed in the tailstock, was used to prevent the sheave from coming loose when it was parted (it would probably never be found again if it left of its own accord!).
 
The body of the pulley was made from a 1/16 strip of .010 brass sheet that had been cut using a paper cutter.  The strip was bent around a 1/32” thick piece of brass strip to get the appropriate shape, and was then bent around a sacrificial piece of wood for drilling.
 
                        
 
A mounting post was soldered to the hole drilled at its base.
 
                        
 
The shape of the body was then finished using a rotary tool and a diamond cylinder.
 
                        
 
The sheave was mounted in the body and soldered on one side of the axle. 
 
                        
 
The pulley was then cleaned up using files and emery paper.
 
The Centerboard Hauling Lanyard comes out of the deck under the dredge winder, with a wooden fairlead in place to keep the lanyard from fraying on the edge of the hole in the deck plank.
 
                        
 
The lanyard then runs under a pulley mounted at deck level just forward of the cabin.
 
                        
 
The lanyard then runs over a pulley on the cabin roof, through a double-block tackle, and is tied off to a cleat.
 
                        
 
The cabin doors are fairly plain, and seem to be made mostly from plywood. The hinges on the real Kathryn are piano hinges painted to match the doors, so they are virtually invisible. The outside of the doors have some strips to provide protection from weather for the separation between the upper and lower parts of each door, between the two doors when they are closed. The interior of the doors are plain and flat.
 
I wanted to leave the doors open so at least some of the cabin details could be seen, but I wasn’t thrilled with having plain flat doors being the only thing showing.  In addition, if the doors were fully opened then the rear windows of the doghouse would be blocked.  To resolve these issues I decided to have the doors propped partially open.
 
Thin pieces of wood strip were shaped so that one edge was angled. These strips were glued to the doors at that angled edge and served as a door jam.
 
                        
 
The door jams were glued to the inside of the door frames.
 
                        
 

 
So now the cabin exterior details are completed.  The only thing left on the cabin is to fabricate the column that contains the controls for the Push Boat.  This will probably be the subject of the next post.
 
Cheers everyone!

Thanks Carl.  We'll find out pretty soon, I hope.

Part 57 – Cabin Exterior Details
 
My original intent was to construct Kathryn’s cabin so that the roof would be removable, allowing the interior of the cabin to be easily seen. After a lot of thought I decided against this for the following reasons:
 
1.    The boom will be very close to the cabin roof, and there would be a real danger of disturbing the boom if the cabin roof was not very carefully moved.
2.    Each cabin door consists of two parts, which allows the doors to be opened for the doghouse while leaving the lower parts closed.  Constructing these doors as two separate parts would make a very delicate part that could be damaged when the roof was removed.
3.    The Centerboard Hauling Lanyard is run over the main roof of the cabin, with pulleys, tackles, and a cleat for securing the lanyard.  Leaving the roof removable would eliminate this interesting detail.
 
The following HAER photo shows some of the detail of the Centerboard Hauling Lanyard.  Also note the controls for the Push Boat just behind the lanyard.
 
                        
 
There are two metal cleats on Kathryn: one that secures the hauling lanyard on the cabin roof, and one that is mounted on top of the bowsprit to secure the jib downhaul.  The other cleats are wooden cleats.
 
The metal cleats for the model were made from 3/64 brass rod and 1/8 x 1/32 brass strip.  The brass rod was flattened on one side using a file.  This would allow the strip to closely mate with the rod.
 
                        
 
A light groove was milled in a piece of Corian to hold the rod so that the strip could be centered on the rod for soldering.
 
                        
 
                        
 
The rod was then cut to the appropriate length with a razor saw. These metal cleats are 8” long (1/4” on the model).
 
                        
 
The strip was narrowed its final width, using a file and a rotary tool.
 
                        
 
The cleat was then ground to its final shape using a rotary tool with diamond cutters, and was polished using emery cloth.  The post for mounting the cleat was also cut into the strip.
 
                        
 
The cleat was then blackened using a well-diluted (5:1) mixture of the JAX Flemish Black, giving a steel-like color.  The following photo shows the jib downhaul cleat in place on the bowsprit.
 
                        
 
There are two open pulleys that service the Centerboard Hauling Lanyard. One is on the deck, with the lanyard running below the sheave.  The other is on the cabin roof, with the lanyard running over the sheave.
 
The sheaves on the model were made from 3/32” brass rod, which would equate to 3” diameter.
 
The rod was bored out for the axle using a center drill followed by a HHS drill.
 
                        
 
The width of the sheave on the model is .020.  A parting tool was used to cut partway through the rod so that this width was set off.  A very small round escapement file was then used to form the groove in the sheave, by carefully filing the shape as the lathe turned at a relatively slow speed.
 
                        
 
The sheave was then parted off using a jewelers saw while the lathe was turned by hand.
 
                        
 
                        
 
A HHS drill bit, reversed in the tailstock, was used to prevent the sheave from coming loose when it was parted (it would probably never be found again if it left of its own accord!).
 
The body of the pulley was made from a 1/16 strip of .010 brass sheet that had been cut using a paper cutter.  The strip was bent around a 1/32” thick piece of brass strip to get the appropriate shape, and was then bent around a sacrificial piece of wood for drilling.
 
                        
 
A mounting post was soldered to the hole drilled at its base.
 
                        
 
The shape of the body was then finished using a rotary tool and a diamond cylinder.
 
                        
 
The sheave was mounted in the body and soldered on one side of the axle. 
 
                        
 
The pulley was then cleaned up using files and emery paper.
 
The Centerboard Hauling Lanyard comes out of the deck under the dredge winder, with a wooden fairlead in place to keep the lanyard from fraying on the edge of the hole in the deck plank.
 
                        
 
The lanyard then runs under a pulley mounted at deck level just forward of the cabin.
 
                        
 
The lanyard then runs over a pulley on the cabin roof, through a double-block tackle, and is tied off to a cleat.
 
                        
 
The cabin doors are fairly plain, and seem to be made mostly from plywood. The hinges on the real Kathryn are piano hinges painted to match the doors, so they are virtually invisible. The outside of the doors have some strips to provide protection from weather for the separation between the upper and lower parts of each door, between the two doors when they are closed. The interior of the doors are plain and flat.
 
I wanted to leave the doors open so at least some of the cabin details could be seen, but I wasn’t thrilled with having plain flat doors being the only thing showing.  In addition, if the doors were fully opened then the rear windows of the doghouse would be blocked.  To resolve these issues I decided to have the doors propped partially open.
 
Thin pieces of wood strip were shaped so that one edge was angled. These strips were glued to the doors at that angled edge and served as a door jam.
 
                        
 
The door jams were glued to the inside of the door frames.
 
                        
 

 
So now the cabin exterior details are completed.  The only thing left on the cabin is to fabricate the column that contains the controls for the Push Boat.  This will probably be the subject of the next post.
 
Cheers everyone!

Part 57 – Cabin Exterior Details
 
My original intent was to construct Kathryn’s cabin so that the roof would be removable, allowing the interior of the cabin to be easily seen. After a lot of thought I decided against this for the following reasons:
 
1.    The boom will be very close to the cabin roof, and there would be a real danger of disturbing the boom if the cabin roof was not very carefully moved.
2.    Each cabin door consists of two parts, which allows the doors to be opened for the doghouse while leaving the lower parts closed.  Constructing these doors as two separate parts would make a very delicate part that could be damaged when the roof was removed.
3.    The Centerboard Hauling Lanyard is run over the main roof of the cabin, with pulleys, tackles, and a cleat for securing the lanyard.  Leaving the roof removable would eliminate this interesting detail.
 
The following HAER photo shows some of the detail of the Centerboard Hauling Lanyard.  Also note the controls for the Push Boat just behind the lanyard.
 
                        
 
There are two metal cleats on Kathryn: one that secures the hauling lanyard on the cabin roof, and one that is mounted on top of the bowsprit to secure the jib downhaul.  The other cleats are wooden cleats.
 
The metal cleats for the model were made from 3/64 brass rod and 1/8 x 1/32 brass strip.  The brass rod was flattened on one side using a file.  This would allow the strip to closely mate with the rod.
 
                        
 
A light groove was milled in a piece of Corian to hold the rod so that the strip could be centered on the rod for soldering.
 
                        
 
                        
 
The rod was then cut to the appropriate length with a razor saw. These metal cleats are 8” long (1/4” on the model).
 
                        
 
The strip was narrowed its final width, using a file and a rotary tool.
 
                        
 
The cleat was then ground to its final shape using a rotary tool with diamond cutters, and was polished using emery cloth.  The post for mounting the cleat was also cut into the strip.
 
                        
 
The cleat was then blackened using a well-diluted (5:1) mixture of the JAX Flemish Black, giving a steel-like color.  The following photo shows the jib downhaul cleat in place on the bowsprit.
 
                        
 
There are two open pulleys that service the Centerboard Hauling Lanyard. One is on the deck, with the lanyard running below the sheave.  The other is on the cabin roof, with the lanyard running over the sheave.
 
The sheaves on the model were made from 3/32” brass rod, which would equate to 3” diameter.
 
The rod was bored out for the axle using a center drill followed by a HHS drill.
 
                        
 
The width of the sheave on the model is .020.  A parting tool was used to cut partway through the rod so that this width was set off.  A very small round escapement file was then used to form the groove in the sheave, by carefully filing the shape as the lathe turned at a relatively slow speed.
 
                        
 
The sheave was then parted off using a jewelers saw while the lathe was turned by hand.
 
                        
 
                        
 
A HHS drill bit, reversed in the tailstock, was used to prevent the sheave from coming loose when it was parted (it would probably never be found again if it left of its own accord!).
 
The body of the pulley was made from a 1/16 strip of .010 brass sheet that had been cut using a paper cutter.  The strip was bent around a 1/32” thick piece of brass strip to get the appropriate shape, and was then bent around a sacrificial piece of wood for drilling.
 
                        
 
A mounting post was soldered to the hole drilled at its base.
 
                        
 
The shape of the body was then finished using a rotary tool and a diamond cylinder.
 
                        
 
The sheave was mounted in the body and soldered on one side of the axle. 
 
                        
 
The pulley was then cleaned up using files and emery paper.
 
The Centerboard Hauling Lanyard comes out of the deck under the dredge winder, with a wooden fairlead in place to keep the lanyard from fraying on the edge of the hole in the deck plank.
 
                        
 
The lanyard then runs under a pulley mounted at deck level just forward of the cabin.
 
                        
 
The lanyard then runs over a pulley on the cabin roof, through a double-block tackle, and is tied off to a cleat.
 
                        
 
The cabin doors are fairly plain, and seem to be made mostly from plywood. The hinges on the real Kathryn are piano hinges painted to match the doors, so they are virtually invisible. The outside of the doors have some strips to provide protection from weather for the separation between the upper and lower parts of each door, between the two doors when they are closed. The interior of the doors are plain and flat.
 
I wanted to leave the doors open so at least some of the cabin details could be seen, but I wasn’t thrilled with having plain flat doors being the only thing showing.  In addition, if the doors were fully opened then the rear windows of the doghouse would be blocked.  To resolve these issues I decided to have the doors propped partially open.
 
Thin pieces of wood strip were shaped so that one edge was angled. These strips were glued to the doors at that angled edge and served as a door jam.
 
                        
 
The door jams were glued to the inside of the door frames.
 
                        
 

 
So now the cabin exterior details are completed.  The only thing left on the cabin is to fabricate the column that contains the controls for the Push Boat.  This will probably be the subject of the next post.
 
Cheers everyone!

Thanks Carl.  We'll find out pretty soon, I hope.

Part 57 – Cabin Exterior Details
 
My original intent was to construct Kathryn’s cabin so that the roof would be removable, allowing the interior of the cabin to be easily seen. After a lot of thought I decided against this for the following reasons:
 
1.    The boom will be very close to the cabin roof, and there would be a real danger of disturbing the boom if the cabin roof was not very carefully moved.
2.    Each cabin door consists of two parts, which allows the doors to be opened for the doghouse while leaving the lower parts closed.  Constructing these doors as two separate parts would make a very delicate part that could be damaged when the roof was removed.
3.    The Centerboard Hauling Lanyard is run over the main roof of the cabin, with pulleys, tackles, and a cleat for securing the lanyard.  Leaving the roof removable would eliminate this interesting detail.
 
The following HAER photo shows some of the detail of the Centerboard Hauling Lanyard.  Also note the controls for the Push Boat just behind the lanyard.
 
                        
 
There are two metal cleats on Kathryn: one that secures the hauling lanyard on the cabin roof, and one that is mounted on top of the bowsprit to secure the jib downhaul.  The other cleats are wooden cleats.
 
The metal cleats for the model were made from 3/64 brass rod and 1/8 x 1/32 brass strip.  The brass rod was flattened on one side using a file.  This would allow the strip to closely mate with the rod.
 
                        
 
A light groove was milled in a piece of Corian to hold the rod so that the strip could be centered on the rod for soldering.
 
                        
 
                        
 
The rod was then cut to the appropriate length with a razor saw. These metal cleats are 8” long (1/4” on the model).
 
                        
 
The strip was narrowed its final width, using a file and a rotary tool.
 
                        
 
The cleat was then ground to its final shape using a rotary tool with diamond cutters, and was polished using emery cloth.  The post for mounting the cleat was also cut into the strip.
 
                        
 
The cleat was then blackened using a well-diluted (5:1) mixture of the JAX Flemish Black, giving a steel-like color.  The following photo shows the jib downhaul cleat in place on the bowsprit.
 
                        
 
There are two open pulleys that service the Centerboard Hauling Lanyard. One is on the deck, with the lanyard running below the sheave.  The other is on the cabin roof, with the lanyard running over the sheave.
 
The sheaves on the model were made from 3/32” brass rod, which would equate to 3” diameter.
 
The rod was bored out for the axle using a center drill followed by a HHS drill.
 
                        
 
The width of the sheave on the model is .020.  A parting tool was used to cut partway through the rod so that this width was set off.  A very small round escapement file was then used to form the groove in the sheave, by carefully filing the shape as the lathe turned at a relatively slow speed.
 
                        
 
The sheave was then parted off using a jewelers saw while the lathe was turned by hand.
 
                        
 
                        
 
A HHS drill bit, reversed in the tailstock, was used to prevent the sheave from coming loose when it was parted (it would probably never be found again if it left of its own accord!).
 
The body of the pulley was made from a 1/16 strip of .010 brass sheet that had been cut using a paper cutter.  The strip was bent around a 1/32” thick piece of brass strip to get the appropriate shape, and was then bent around a sacrificial piece of wood for drilling.
 
                        
 
A mounting post was soldered to the hole drilled at its base.
 
                        
 
The shape of the body was then finished using a rotary tool and a diamond cylinder.
 
                        
 
The sheave was mounted in the body and soldered on one side of the axle. 
 
                        
 
The pulley was then cleaned up using files and emery paper.
 
The Centerboard Hauling Lanyard comes out of the deck under the dredge winder, with a wooden fairlead in place to keep the lanyard from fraying on the edge of the hole in the deck plank.
 
                        
 
The lanyard then runs under a pulley mounted at deck level just forward of the cabin.
 
                        
 
The lanyard then runs over a pulley on the cabin roof, through a double-block tackle, and is tied off to a cleat.
 
                        
 
The cabin doors are fairly plain, and seem to be made mostly from plywood. The hinges on the real Kathryn are piano hinges painted to match the doors, so they are virtually invisible. The outside of the doors have some strips to provide protection from weather for the separation between the upper and lower parts of each door, between the two doors when they are closed. The interior of the doors are plain and flat.
 
I wanted to leave the doors open so at least some of the cabin details could be seen, but I wasn’t thrilled with having plain flat doors being the only thing showing.  In addition, if the doors were fully opened then the rear windows of the doghouse would be blocked.  To resolve these issues I decided to have the doors propped partially open.
 
Thin pieces of wood strip were shaped so that one edge was angled. These strips were glued to the doors at that angled edge and served as a door jam.
 
                        
 
The door jams were glued to the inside of the door frames.
 
                        
 

 
So now the cabin exterior details are completed.  The only thing left on the cabin is to fabricate the column that contains the controls for the Push Boat.  This will probably be the subject of the next post.
 
Cheers everyone!

Part 57 – Cabin Exterior Details
 
My original intent was to construct Kathryn’s cabin so that the roof would be removable, allowing the interior of the cabin to be easily seen. After a lot of thought I decided against this for the following reasons:
 
1.    The boom will be very close to the cabin roof, and there would be a real danger of disturbing the boom if the cabin roof was not very carefully moved.
2.    Each cabin door consists of two parts, which allows the doors to be opened for the doghouse while leaving the lower parts closed.  Constructing these doors as two separate parts would make a very delicate part that could be damaged when the roof was removed.
3.    The Centerboard Hauling Lanyard is run over the main roof of the cabin, with pulleys, tackles, and a cleat for securing the lanyard.  Leaving the roof removable would eliminate this interesting detail.
 
The following HAER photo shows some of the detail of the Centerboard Hauling Lanyard.  Also note the controls for the Push Boat just behind the lanyard.
 
                        
 
There are two metal cleats on Kathryn: one that secures the hauling lanyard on the cabin roof, and one that is mounted on top of the bowsprit to secure the jib downhaul.  The other cleats are wooden cleats.
 
The metal cleats for the model were made from 3/64 brass rod and 1/8 x 1/32 brass strip.  The brass rod was flattened on one side using a file.  This would allow the strip to closely mate with the rod.
 
                        
 
A light groove was milled in a piece of Corian to hold the rod so that the strip could be centered on the rod for soldering.
 
                        
 
                        
 
The rod was then cut to the appropriate length with a razor saw. These metal cleats are 8” long (1/4” on the model).
 
                        
 
The strip was narrowed its final width, using a file and a rotary tool.
 
                        
 
The cleat was then ground to its final shape using a rotary tool with diamond cutters, and was polished using emery cloth.  The post for mounting the cleat was also cut into the strip.
 
                        
 
The cleat was then blackened using a well-diluted (5:1) mixture of the JAX Flemish Black, giving a steel-like color.  The following photo shows the jib downhaul cleat in place on the bowsprit.
 
                        
 
There are two open pulleys that service the Centerboard Hauling Lanyard. One is on the deck, with the lanyard running below the sheave.  The other is on the cabin roof, with the lanyard running over the sheave.
 
The sheaves on the model were made from 3/32” brass rod, which would equate to 3” diameter.
 
The rod was bored out for the axle using a center drill followed by a HHS drill.
 
                        
 
The width of the sheave on the model is .020.  A parting tool was used to cut partway through the rod so that this width was set off.  A very small round escapement file was then used to form the groove in the sheave, by carefully filing the shape as the lathe turned at a relatively slow speed.
 
                        
 
The sheave was then parted off using a jewelers saw while the lathe was turned by hand.
 
                        
 
                        
 
A HHS drill bit, reversed in the tailstock, was used to prevent the sheave from coming loose when it was parted (it would probably never be found again if it left of its own accord!).
 
The body of the pulley was made from a 1/16 strip of .010 brass sheet that had been cut using a paper cutter.  The strip was bent around a 1/32” thick piece of brass strip to get the appropriate shape, and was then bent around a sacrificial piece of wood for drilling.
 
                        
 
A mounting post was soldered to the hole drilled at its base.
 
                        
 
The shape of the body was then finished using a rotary tool and a diamond cylinder.
 
                        
 
The sheave was mounted in the body and soldered on one side of the axle. 
 
                        
 
The pulley was then cleaned up using files and emery paper.
 
The Centerboard Hauling Lanyard comes out of the deck under the dredge winder, with a wooden fairlead in place to keep the lanyard from fraying on the edge of the hole in the deck plank.
 
                        
 
The lanyard then runs under a pulley mounted at deck level just forward of the cabin.
 
                        
 
The lanyard then runs over a pulley on the cabin roof, through a double-block tackle, and is tied off to a cleat.
 
                        
 
The cabin doors are fairly plain, and seem to be made mostly from plywood. The hinges on the real Kathryn are piano hinges painted to match the doors, so they are virtually invisible. The outside of the doors have some strips to provide protection from weather for the separation between the upper and lower parts of each door, between the two doors when they are closed. The interior of the doors are plain and flat.
 
I wanted to leave the doors open so at least some of the cabin details could be seen, but I wasn’t thrilled with having plain flat doors being the only thing showing.  In addition, if the doors were fully opened then the rear windows of the doghouse would be blocked.  To resolve these issues I decided to have the doors propped partially open.
 
Thin pieces of wood strip were shaped so that one edge was angled. These strips were glued to the doors at that angled edge and served as a door jam.
 
                        
 
The door jams were glued to the inside of the door frames.
 
                        
 

 
So now the cabin exterior details are completed.  The only thing left on the cabin is to fabricate the column that contains the controls for the Push Boat.  This will probably be the subject of the next post.
 
Cheers everyone!

Thanks Carl.  We'll find out pretty soon, I hope.

Pros and cons of CNC Mill
 
The advantages obtained by CNC capability on the mill include:
 
  ability to move the cutter in any of the 4 axes simultaneously (e.g. milling an arc)
  precise control over movements
  ability to reproduce multiple identical parts
  the joy of watching the machine do the work
 
The disadvantages include:
  having to specify milling intentions in a very primitive programming language (g-code)
  learning curve of the CNC programming language (g-code)
  cost of the system
 
Things I still have to explore:
   CAM software for designing parts (I’ve played with FreeCAD and ben frustrated,  will try out Fusion360)
   Path generating software ( to take CAM model and generate the g-code to machine the part.
 
Things to be aware of:
  There is no magic in the systems at present  You still have to know how the part can be milled.  You have to specify the order things happen, the tools to use, and you have to know the capabilities and limitation of your particular mill and tools.
 
 

Part 57 – Cabin Exterior Details
 
My original intent was to construct Kathryn’s cabin so that the roof would be removable, allowing the interior of the cabin to be easily seen. After a lot of thought I decided against this for the following reasons:
 
1.    The boom will be very close to the cabin roof, and there would be a real danger of disturbing the boom if the cabin roof was not very carefully moved.
2.    Each cabin door consists of two parts, which allows the doors to be opened for the doghouse while leaving the lower parts closed.  Constructing these doors as two separate parts would make a very delicate part that could be damaged when the roof was removed.
3.    The Centerboard Hauling Lanyard is run over the main roof of the cabin, with pulleys, tackles, and a cleat for securing the lanyard.  Leaving the roof removable would eliminate this interesting detail.
 
The following HAER photo shows some of the detail of the Centerboard Hauling Lanyard.  Also note the controls for the Push Boat just behind the lanyard.
 
                        
 
There are two metal cleats on Kathryn: one that secures the hauling lanyard on the cabin roof, and one that is mounted on top of the bowsprit to secure the jib downhaul.  The other cleats are wooden cleats.
 
The metal cleats for the model were made from 3/64 brass rod and 1/8 x 1/32 brass strip.  The brass rod was flattened on one side using a file.  This would allow the strip to closely mate with the rod.
 
                        
 
A light groove was milled in a piece of Corian to hold the rod so that the strip could be centered on the rod for soldering.
 
                        
 
                        
 
The rod was then cut to the appropriate length with a razor saw. These metal cleats are 8” long (1/4” on the model).
 
                        
 
The strip was narrowed its final width, using a file and a rotary tool.
 
                        
 
The cleat was then ground to its final shape using a rotary tool with diamond cutters, and was polished using emery cloth.  The post for mounting the cleat was also cut into the strip.
 
                        
 
The cleat was then blackened using a well-diluted (5:1) mixture of the JAX Flemish Black, giving a steel-like color.  The following photo shows the jib downhaul cleat in place on the bowsprit.
 
                        
 
There are two open pulleys that service the Centerboard Hauling Lanyard. One is on the deck, with the lanyard running below the sheave.  The other is on the cabin roof, with the lanyard running over the sheave.
 
The sheaves on the model were made from 3/32” brass rod, which would equate to 3” diameter.
 
The rod was bored out for the axle using a center drill followed by a HHS drill.
 
                        
 
The width of the sheave on the model is .020.  A parting tool was used to cut partway through the rod so that this width was set off.  A very small round escapement file was then used to form the groove in the sheave, by carefully filing the shape as the lathe turned at a relatively slow speed.
 
                        
 
The sheave was then parted off using a jewelers saw while the lathe was turned by hand.
 
                        
 
                        
 
A HHS drill bit, reversed in the tailstock, was used to prevent the sheave from coming loose when it was parted (it would probably never be found again if it left of its own accord!).
 
The body of the pulley was made from a 1/16 strip of .010 brass sheet that had been cut using a paper cutter.  The strip was bent around a 1/32” thick piece of brass strip to get the appropriate shape, and was then bent around a sacrificial piece of wood for drilling.
 
                        
 
A mounting post was soldered to the hole drilled at its base.
 
                        
 
The shape of the body was then finished using a rotary tool and a diamond cylinder.
 
                        
 
The sheave was mounted in the body and soldered on one side of the axle. 
 
                        
 
The pulley was then cleaned up using files and emery paper.
 
The Centerboard Hauling Lanyard comes out of the deck under the dredge winder, with a wooden fairlead in place to keep the lanyard from fraying on the edge of the hole in the deck plank.
 
                        
 
The lanyard then runs under a pulley mounted at deck level just forward of the cabin.
 
                        
 
The lanyard then runs over a pulley on the cabin roof, through a double-block tackle, and is tied off to a cleat.
 
                        
 
The cabin doors are fairly plain, and seem to be made mostly from plywood. The hinges on the real Kathryn are piano hinges painted to match the doors, so they are virtually invisible. The outside of the doors have some strips to provide protection from weather for the separation between the upper and lower parts of each door, between the two doors when they are closed. The interior of the doors are plain and flat.
 
I wanted to leave the doors open so at least some of the cabin details could be seen, but I wasn’t thrilled with having plain flat doors being the only thing showing.  In addition, if the doors were fully opened then the rear windows of the doghouse would be blocked.  To resolve these issues I decided to have the doors propped partially open.
 
Thin pieces of wood strip were shaped so that one edge was angled. These strips were glued to the doors at that angled edge and served as a door jam.
 
                        
 
The door jams were glued to the inside of the door frames.
 
                        
 

 
So now the cabin exterior details are completed.  The only thing left on the cabin is to fabricate the column that contains the controls for the Push Boat.  This will probably be the subject of the next post.
 
Cheers everyone!

Part 57 – Cabin Exterior Details
 
My original intent was to construct Kathryn’s cabin so that the roof would be removable, allowing the interior of the cabin to be easily seen. After a lot of thought I decided against this for the following reasons:
 
1.    The boom will be very close to the cabin roof, and there would be a real danger of disturbing the boom if the cabin roof was not very carefully moved.
2.    Each cabin door consists of two parts, which allows the doors to be opened for the doghouse while leaving the lower parts closed.  Constructing these doors as two separate parts would make a very delicate part that could be damaged when the roof was removed.
3.    The Centerboard Hauling Lanyard is run over the main roof of the cabin, with pulleys, tackles, and a cleat for securing the lanyard.  Leaving the roof removable would eliminate this interesting detail.
 
The following HAER photo shows some of the detail of the Centerboard Hauling Lanyard.  Also note the controls for the Push Boat just behind the lanyard.
 
                        
 
There are two metal cleats on Kathryn: one that secures the hauling lanyard on the cabin roof, and one that is mounted on top of the bowsprit to secure the jib downhaul.  The other cleats are wooden cleats.
 
The metal cleats for the model were made from 3/64 brass rod and 1/8 x 1/32 brass strip.  The brass rod was flattened on one side using a file.  This would allow the strip to closely mate with the rod.
 
                        
 
A light groove was milled in a piece of Corian to hold the rod so that the strip could be centered on the rod for soldering.
 
                        
 
                        
 
The rod was then cut to the appropriate length with a razor saw. These metal cleats are 8” long (1/4” on the model).
 
                        
 
The strip was narrowed its final width, using a file and a rotary tool.
 
                        
 
The cleat was then ground to its final shape using a rotary tool with diamond cutters, and was polished using emery cloth.  The post for mounting the cleat was also cut into the strip.
 
                        
 
The cleat was then blackened using a well-diluted (5:1) mixture of the JAX Flemish Black, giving a steel-like color.  The following photo shows the jib downhaul cleat in place on the bowsprit.
 
                        
 
There are two open pulleys that service the Centerboard Hauling Lanyard. One is on the deck, with the lanyard running below the sheave.  The other is on the cabin roof, with the lanyard running over the sheave.
 
The sheaves on the model were made from 3/32” brass rod, which would equate to 3” diameter.
 
The rod was bored out for the axle using a center drill followed by a HHS drill.
 
                        
 
The width of the sheave on the model is .020.  A parting tool was used to cut partway through the rod so that this width was set off.  A very small round escapement file was then used to form the groove in the sheave, by carefully filing the shape as the lathe turned at a relatively slow speed.
 
                        
 
The sheave was then parted off using a jewelers saw while the lathe was turned by hand.
 
                        
 
                        
 
A HHS drill bit, reversed in the tailstock, was used to prevent the sheave from coming loose when it was parted (it would probably never be found again if it left of its own accord!).
 
The body of the pulley was made from a 1/16 strip of .010 brass sheet that had been cut using a paper cutter.  The strip was bent around a 1/32” thick piece of brass strip to get the appropriate shape, and was then bent around a sacrificial piece of wood for drilling.
 
                        
 
A mounting post was soldered to the hole drilled at its base.
 
                        
 
The shape of the body was then finished using a rotary tool and a diamond cylinder.
 
                        
 
The sheave was mounted in the body and soldered on one side of the axle. 
 
                        
 
The pulley was then cleaned up using files and emery paper.
 
The Centerboard Hauling Lanyard comes out of the deck under the dredge winder, with a wooden fairlead in place to keep the lanyard from fraying on the edge of the hole in the deck plank.
 
                        
 
The lanyard then runs under a pulley mounted at deck level just forward of the cabin.
 
                        
 
The lanyard then runs over a pulley on the cabin roof, through a double-block tackle, and is tied off to a cleat.
 
                        
 
The cabin doors are fairly plain, and seem to be made mostly from plywood. The hinges on the real Kathryn are piano hinges painted to match the doors, so they are virtually invisible. The outside of the doors have some strips to provide protection from weather for the separation between the upper and lower parts of each door, between the two doors when they are closed. The interior of the doors are plain and flat.
 
I wanted to leave the doors open so at least some of the cabin details could be seen, but I wasn’t thrilled with having plain flat doors being the only thing showing.  In addition, if the doors were fully opened then the rear windows of the doghouse would be blocked.  To resolve these issues I decided to have the doors propped partially open.
 
Thin pieces of wood strip were shaped so that one edge was angled. These strips were glued to the doors at that angled edge and served as a door jam.
 
                        
 
The door jams were glued to the inside of the door frames.
 
                        
 

 
So now the cabin exterior details are completed.  The only thing left on the cabin is to fabricate the column that contains the controls for the Push Boat.  This will probably be the subject of the next post.
 
Cheers everyone!