bartley

Post 31: Bowsprit
 
I am in the process of constructing the remaining deck furniture - Windlass etc.  However, I decided to make and trial fit the bowsprit so that I can avoid maneuvering around the deck fittings. I turned this from 5/16 square stock as suggested by chuck.  I drilled three 1.5 mm holes while the stock was still square and also the holes for the sheave at the tip
 

I then turned this on my home made "lathe"

The board at the end has a Roller Blade bearing.  I actually have two of these and on longer jobs I position one about half way along to add extra support.  I find this works pretty well and is cheap!
 
Of course I had to enlarge the hole in the bow to fit.  Initially, I did this with drills of increasing diameter but this led to tearing of the timber so in the end I did most of the work with a round file.  Here is the fitted bowsprit:
 

 
John
 
 

Very impressive Glen.  Have a look at mine at the same stage.  Just lacks the crispness of yours doesn't it?
 

 
John
 

Yes Glenn, this was done . I notice that this photo was taken nearly a year ago so I am well past that stage now.
 
Cheers,
 
John

Very impressive Glen.  Have a look at mine at the same stage.  Just lacks the crispness of yours doesn't it?
 

 
John
 

Yes Glenn, this was done . I notice that this photo was taken nearly a year ago so I am well past that stage now.
 
Cheers,
 
John

Very impressive Glen.  Have a look at mine at the same stage.  Just lacks the crispness of yours doesn't it?
 

 
John
 

Very impressive Glen.  Have a look at mine at the same stage.  Just lacks the crispness of yours doesn't it?
 

 
John
 

Very impressive Glen.  Have a look at mine at the same stage.  Just lacks the crispness of yours doesn't it?
 

 
John
 

I use a small plastic sieve to contain my parts and use Sparex to clean off the contamination.  So the sieve containing the parts goes into the Sparex for a couple of minutes then into a bicarbonate bath to neutralise and wash under running water.  Then into the blackening reagent (no drying).  Again into the bicarbonate to quench the reaction then wash again in running water.  Only then do I dry the parts before gently polishing with a micro-fibre cloth. I used to use an acetone step but no longer find it necessary. If I did I would allow to dry before the next step.  But acetone dries quite quickly.
 
John

As has been mentioned here before, take care with this stuff .All these preparations contain selenium dioxide (or selenious acid when it is in solution- same stuff in a different form). This stuff is  highly toxic so wear gloves and ensure good ventilation.
 
Now, what is happening here is what chemists call a Redox Reaction.  Modellers certainly do not need know any chemistry but there are a couple of important consequences of the chemistry.  Firstly the metal (or actually the copper in the brass) is etched away by the selenious acid and goes into solution as copper ions.  At the same time the selenious acid is converted to selenium metal (which is black) and this is deposited as a tiny black spec in place from which the copper was removed.  
 
So notice that the Selenium metal is not chemically attached to the metal in any way so it can be removed by mechanical action.  Also although others have warned about the flaking that is a consequence of prolonged action a second effect is that more of the metal surface is etched and surface detail is compromised.  Obviously this is not important for an eyepin but more significant for a cannon, say.  In the minute or so that it takes to achieve a good result this would be barely noticeable but if one were persist for half an hour there would be noticeable pitting and significant loss of detail.
 
All of these products also contain a mineral acid (nitric in Jax Black, hydrochloric in Jax Pewter Black, and phosphoric in Birchwood  Casey) and they also usually contain some copper sulfate, which is there to moderate the reaction. This, of course, is the blue colour of the product
 
The Birchwood  Casey product also contains molybdate  which acts in a similar way but with the zinc in the alloy.  So you possibly get a deeper black since both components of the brass are being blackened.
 
After the initial blackening most people polish the surface to remove any excess flaking.  So the black stuff, which ends up on the cloth (in dvm27’s post for example) is Selenium metal which is also toxic and worse still it is a dust, which you can breath in.  I would not be polishing with a power tool but if you must, wear a mask and gloves.  If you get black on your fingers don’t go and eat your lunch with out washing it off with copious soap and water!
 
John

As has been mentioned here before, take care with this stuff .All these preparations contain selenium dioxide (or selenious acid when it is in solution- same stuff in a different form). This stuff is  highly toxic so wear gloves and ensure good ventilation.
 
Now, what is happening here is what chemists call a Redox Reaction.  Modellers certainly do not need know any chemistry but there are a couple of important consequences of the chemistry.  Firstly the metal (or actually the copper in the brass) is etched away by the selenious acid and goes into solution as copper ions.  At the same time the selenious acid is converted to selenium metal (which is black) and this is deposited as a tiny black spec in place from which the copper was removed.  
 
So notice that the Selenium metal is not chemically attached to the metal in any way so it can be removed by mechanical action.  Also although others have warned about the flaking that is a consequence of prolonged action a second effect is that more of the metal surface is etched and surface detail is compromised.  Obviously this is not important for an eyepin but more significant for a cannon, say.  In the minute or so that it takes to achieve a good result this would be barely noticeable but if one were persist for half an hour there would be noticeable pitting and significant loss of detail.
 
All of these products also contain a mineral acid (nitric in Jax Black, hydrochloric in Jax Pewter Black, and phosphoric in Birchwood  Casey) and they also usually contain some copper sulfate, which is there to moderate the reaction. This, of course, is the blue colour of the product
 
The Birchwood  Casey product also contains molybdate  which acts in a similar way but with the zinc in the alloy.  So you possibly get a deeper black since both components of the brass are being blackened.
 
After the initial blackening most people polish the surface to remove any excess flaking.  So the black stuff, which ends up on the cloth (in dvm27’s post for example) is Selenium metal which is also toxic and worse still it is a dust, which you can breath in.  I would not be polishing with a power tool but if you must, wear a mask and gloves.  If you get black on your fingers don’t go and eat your lunch with out washing it off with copious soap and water!
 
John

I use a small plastic sieve to contain my parts and use Sparex to clean off the contamination.  So the sieve containing the parts goes into the Sparex for a couple of minutes then into a bicarbonate bath to neutralise and wash under running water.  Then into the blackening reagent (no drying).  Again into the bicarbonate to quench the reaction then wash again in running water.  Only then do I dry the parts before gently polishing with a micro-fibre cloth. I used to use an acetone step but no longer find it necessary. If I did I would allow to dry before the next step.  But acetone dries quite quickly.
 
John

I use a small plastic sieve to contain my parts and use Sparex to clean off the contamination.  So the sieve containing the parts goes into the Sparex for a couple of minutes then into a bicarbonate bath to neutralise and wash under running water.  Then into the blackening reagent (no drying).  Again into the bicarbonate to quench the reaction then wash again in running water.  Only then do I dry the parts before gently polishing with a micro-fibre cloth. I used to use an acetone step but no longer find it necessary. If I did I would allow to dry before the next step.  But acetone dries quite quickly.
 
John

As has been mentioned here before, take care with this stuff .All these preparations contain selenium dioxide (or selenious acid when it is in solution- same stuff in a different form). This stuff is  highly toxic so wear gloves and ensure good ventilation.
 
Now, what is happening here is what chemists call a Redox Reaction.  Modellers certainly do not need know any chemistry but there are a couple of important consequences of the chemistry.  Firstly the metal (or actually the copper in the brass) is etched away by the selenious acid and goes into solution as copper ions.  At the same time the selenious acid is converted to selenium metal (which is black) and this is deposited as a tiny black spec in place from which the copper was removed.  
 
So notice that the Selenium metal is not chemically attached to the metal in any way so it can be removed by mechanical action.  Also although others have warned about the flaking that is a consequence of prolonged action a second effect is that more of the metal surface is etched and surface detail is compromised.  Obviously this is not important for an eyepin but more significant for a cannon, say.  In the minute or so that it takes to achieve a good result this would be barely noticeable but if one were persist for half an hour there would be noticeable pitting and significant loss of detail.
 
All of these products also contain a mineral acid (nitric in Jax Black, hydrochloric in Jax Pewter Black, and phosphoric in Birchwood  Casey) and they also usually contain some copper sulfate, which is there to moderate the reaction. This, of course, is the blue colour of the product
 
The Birchwood  Casey product also contains molybdate  which acts in a similar way but with the zinc in the alloy.  So you possibly get a deeper black since both components of the brass are being blackened.
 
After the initial blackening most people polish the surface to remove any excess flaking.  So the black stuff, which ends up on the cloth (in dvm27’s post for example) is Selenium metal which is also toxic and worse still it is a dust, which you can breath in.  I would not be polishing with a power tool but if you must, wear a mask and gloves.  If you get black on your fingers don’t go and eat your lunch with out washing it off with copious soap and water!
 
John

As has been mentioned here before, take care with this stuff .All these preparations contain selenium dioxide (or selenious acid when it is in solution- same stuff in a different form). This stuff is  highly toxic so wear gloves and ensure good ventilation.
 
Now, what is happening here is what chemists call a Redox Reaction.  Modellers certainly do not need know any chemistry but there are a couple of important consequences of the chemistry.  Firstly the metal (or actually the copper in the brass) is etched away by the selenious acid and goes into solution as copper ions.  At the same time the selenious acid is converted to selenium metal (which is black) and this is deposited as a tiny black spec in place from which the copper was removed.  
 
So notice that the Selenium metal is not chemically attached to the metal in any way so it can be removed by mechanical action.  Also although others have warned about the flaking that is a consequence of prolonged action a second effect is that more of the metal surface is etched and surface detail is compromised.  Obviously this is not important for an eyepin but more significant for a cannon, say.  In the minute or so that it takes to achieve a good result this would be barely noticeable but if one were persist for half an hour there would be noticeable pitting and significant loss of detail.
 
All of these products also contain a mineral acid (nitric in Jax Black, hydrochloric in Jax Pewter Black, and phosphoric in Birchwood  Casey) and they also usually contain some copper sulfate, which is there to moderate the reaction. This, of course, is the blue colour of the product
 
The Birchwood  Casey product also contains molybdate  which acts in a similar way but with the zinc in the alloy.  So you possibly get a deeper black since both components of the brass are being blackened.
 
After the initial blackening most people polish the surface to remove any excess flaking.  So the black stuff, which ends up on the cloth (in dvm27’s post for example) is Selenium metal which is also toxic and worse still it is a dust, which you can breath in.  I would not be polishing with a power tool but if you must, wear a mask and gloves.  If you get black on your fingers don’t go and eat your lunch with out washing it off with copious soap and water!
 
John

As has been mentioned here before, take care with this stuff .All these preparations contain selenium dioxide (or selenious acid when it is in solution- same stuff in a different form). This stuff is  highly toxic so wear gloves and ensure good ventilation.
 
Now, what is happening here is what chemists call a Redox Reaction.  Modellers certainly do not need know any chemistry but there are a couple of important consequences of the chemistry.  Firstly the metal (or actually the copper in the brass) is etched away by the selenious acid and goes into solution as copper ions.  At the same time the selenious acid is converted to selenium metal (which is black) and this is deposited as a tiny black spec in place from which the copper was removed.  
 
So notice that the Selenium metal is not chemically attached to the metal in any way so it can be removed by mechanical action.  Also although others have warned about the flaking that is a consequence of prolonged action a second effect is that more of the metal surface is etched and surface detail is compromised.  Obviously this is not important for an eyepin but more significant for a cannon, say.  In the minute or so that it takes to achieve a good result this would be barely noticeable but if one were persist for half an hour there would be noticeable pitting and significant loss of detail.
 
All of these products also contain a mineral acid (nitric in Jax Black, hydrochloric in Jax Pewter Black, and phosphoric in Birchwood  Casey) and they also usually contain some copper sulfate, which is there to moderate the reaction. This, of course, is the blue colour of the product
 
The Birchwood  Casey product also contains molybdate  which acts in a similar way but with the zinc in the alloy.  So you possibly get a deeper black since both components of the brass are being blackened.
 
After the initial blackening most people polish the surface to remove any excess flaking.  So the black stuff, which ends up on the cloth (in dvm27’s post for example) is Selenium metal which is also toxic and worse still it is a dust, which you can breath in.  I would not be polishing with a power tool but if you must, wear a mask and gloves.  If you get black on your fingers don’t go and eat your lunch with out washing it off with copious soap and water!
 
John

As has been mentioned here before, take care with this stuff .All these preparations contain selenium dioxide (or selenious acid when it is in solution- same stuff in a different form). This stuff is  highly toxic so wear gloves and ensure good ventilation.
 
Now, what is happening here is what chemists call a Redox Reaction.  Modellers certainly do not need know any chemistry but there are a couple of important consequences of the chemistry.  Firstly the metal (or actually the copper in the brass) is etched away by the selenious acid and goes into solution as copper ions.  At the same time the selenious acid is converted to selenium metal (which is black) and this is deposited as a tiny black spec in place from which the copper was removed.  
 
So notice that the Selenium metal is not chemically attached to the metal in any way so it can be removed by mechanical action.  Also although others have warned about the flaking that is a consequence of prolonged action a second effect is that more of the metal surface is etched and surface detail is compromised.  Obviously this is not important for an eyepin but more significant for a cannon, say.  In the minute or so that it takes to achieve a good result this would be barely noticeable but if one were persist for half an hour there would be noticeable pitting and significant loss of detail.
 
All of these products also contain a mineral acid (nitric in Jax Black, hydrochloric in Jax Pewter Black, and phosphoric in Birchwood  Casey) and they also usually contain some copper sulfate, which is there to moderate the reaction. This, of course, is the blue colour of the product
 
The Birchwood  Casey product also contains molybdate  which acts in a similar way but with the zinc in the alloy.  So you possibly get a deeper black since both components of the brass are being blackened.
 
After the initial blackening most people polish the surface to remove any excess flaking.  So the black stuff, which ends up on the cloth (in dvm27’s post for example) is Selenium metal which is also toxic and worse still it is a dust, which you can breath in.  I would not be polishing with a power tool but if you must, wear a mask and gloves.  If you get black on your fingers don’t go and eat your lunch with out washing it off with copious soap and water!
 
John

As has been mentioned here before, take care with this stuff .All these preparations contain selenium dioxide (or selenious acid when it is in solution- same stuff in a different form). This stuff is  highly toxic so wear gloves and ensure good ventilation.
 
Now, what is happening here is what chemists call a Redox Reaction.  Modellers certainly do not need know any chemistry but there are a couple of important consequences of the chemistry.  Firstly the metal (or actually the copper in the brass) is etched away by the selenious acid and goes into solution as copper ions.  At the same time the selenious acid is converted to selenium metal (which is black) and this is deposited as a tiny black spec in place from which the copper was removed.  
 
So notice that the Selenium metal is not chemically attached to the metal in any way so it can be removed by mechanical action.  Also although others have warned about the flaking that is a consequence of prolonged action a second effect is that more of the metal surface is etched and surface detail is compromised.  Obviously this is not important for an eyepin but more significant for a cannon, say.  In the minute or so that it takes to achieve a good result this would be barely noticeable but if one were persist for half an hour there would be noticeable pitting and significant loss of detail.
 
All of these products also contain a mineral acid (nitric in Jax Black, hydrochloric in Jax Pewter Black, and phosphoric in Birchwood  Casey) and they also usually contain some copper sulfate, which is there to moderate the reaction. This, of course, is the blue colour of the product
 
The Birchwood  Casey product also contains molybdate  which acts in a similar way but with the zinc in the alloy.  So you possibly get a deeper black since both components of the brass are being blackened.
 
After the initial blackening most people polish the surface to remove any excess flaking.  So the black stuff, which ends up on the cloth (in dvm27’s post for example) is Selenium metal which is also toxic and worse still it is a dust, which you can breath in.  I would not be polishing with a power tool but if you must, wear a mask and gloves.  If you get black on your fingers don’t go and eat your lunch with out washing it off with copious soap and water!
 
John

As has been mentioned here before, take care with this stuff .All these preparations contain selenium dioxide (or selenious acid when it is in solution- same stuff in a different form). This stuff is  highly toxic so wear gloves and ensure good ventilation.
 
Now, what is happening here is what chemists call a Redox Reaction.  Modellers certainly do not need know any chemistry but there are a couple of important consequences of the chemistry.  Firstly the metal (or actually the copper in the brass) is etched away by the selenious acid and goes into solution as copper ions.  At the same time the selenious acid is converted to selenium metal (which is black) and this is deposited as a tiny black spec in place from which the copper was removed.  
 
So notice that the Selenium metal is not chemically attached to the metal in any way so it can be removed by mechanical action.  Also although others have warned about the flaking that is a consequence of prolonged action a second effect is that more of the metal surface is etched and surface detail is compromised.  Obviously this is not important for an eyepin but more significant for a cannon, say.  In the minute or so that it takes to achieve a good result this would be barely noticeable but if one were persist for half an hour there would be noticeable pitting and significant loss of detail.
 
All of these products also contain a mineral acid (nitric in Jax Black, hydrochloric in Jax Pewter Black, and phosphoric in Birchwood  Casey) and they also usually contain some copper sulfate, which is there to moderate the reaction. This, of course, is the blue colour of the product
 
The Birchwood  Casey product also contains molybdate  which acts in a similar way but with the zinc in the alloy.  So you possibly get a deeper black since both components of the brass are being blackened.
 
After the initial blackening most people polish the surface to remove any excess flaking.  So the black stuff, which ends up on the cloth (in dvm27’s post for example) is Selenium metal which is also toxic and worse still it is a dust, which you can breath in.  I would not be polishing with a power tool but if you must, wear a mask and gloves.  If you get black on your fingers don’t go and eat your lunch with out washing it off with copious soap and water!
 
John

Hi Jaeger,
 
On the subject of wind speed - or really "apparent" wind speed. It depends on the point of sailing. If you are sailing before the wind then as you say the apparent wind is less than the true wind speed but if you are sailing into the breeze then the apparent wind is stronger than the true wind.  Also since the boat is at an angle to the wind at this point of sailing the addition of vectors causes the apparent wind to move aft.  But you are definitely correct about the lack of shade on deck!
 
John

Hi Jaeger,
 
On the subject of wind speed - or really "apparent" wind speed. It depends on the point of sailing. If you are sailing before the wind then as you say the apparent wind is less than the true wind speed but if you are sailing into the breeze then the apparent wind is stronger than the true wind.  Also since the boat is at an angle to the wind at this point of sailing the addition of vectors causes the apparent wind to move aft.  But you are definitely correct about the lack of shade on deck!
 
John

Jaeger,
 
I suspect volatility might be a factor.  The IPA with a boiling point of around 83 will stay in contact with the PVA rather longer than ethanol. I don't think polarity differences are  that much.  IPA is marginally more aliphatic.  Certainly 1-propanol has less solvent powerfor polar substances than ethanol.
 
John

You are right Glen it doesn't take much to tighten up the joint.  When I started out I tried to get it exact and as you say a little gentle sanding  is all that's needed.  My point was don't overdo because it will look good initially but worse after sanding.
 
John

Glen,
Your planking is excellent.  Much better than mine which has a few deficiencies but because I was using boxwood and my supplies were limited I could not afford to rip off too many planks!
 
On the subject of beveling - I am sure you know this as your planking is so good but perhaps for the benefit of others over beveling can be as bad as no beveling if you have to sand the hull much.  So I think it needs to be reasonably correct.
 
                               
 
 

Glen,
Your planking is excellent.  Much better than mine which has a few deficiencies but because I was using boxwood and my supplies were limited I could not afford to rip off too many planks!
 
On the subject of beveling - I am sure you know this as your planking is so good but perhaps for the benefit of others over beveling can be as bad as no beveling if you have to sand the hull much.  So I think it needs to be reasonably correct.