bartley

Glenn,
 
You have clearly solved the problem of fabricating a moulding cutter now but for the record, and perhaps for a later build, this is an escapement file which I used to cut my profile.
 
This is a round one but other profiles are available. The widest part on this one is 1 .5mm and the tip is 0.4 mm - very delicate but with care, especially on brass, very narrow cuts can be made.
 


Cheers,
 
John
 

Glenn,
 
You have clearly solved the problem of fabricating a moulding cutter now but for the record, and perhaps for a later build, this is an escapement file which I used to cut my profile.
 
This is a round one but other profiles are available. The widest part on this one is 1 .5mm and the tip is 0.4 mm - very delicate but with care, especially on brass, very narrow cuts can be made.
 


Cheers,
 
John
 

Glenn,
 
You have clearly solved the problem of fabricating a moulding cutter now but for the record, and perhaps for a later build, this is an escapement file which I used to cut my profile.
 
This is a round one but other profiles are available. The widest part on this one is 1 .5mm and the tip is 0.4 mm - very delicate but with care, especially on brass, very narrow cuts can be made.
 


Cheers,
 
John
 

Yes indeed Kurt, boiling Sparex (which is incidentally an expensive packet of sodium hydrogen sulfate) could be dangerous because once dissolved it is sulfuric acid.  It is quite dilute initially but if it becomes concentrated by boiling it will produce oxides of sulfur (chemically SO2 and SO3). These are dangerous gases and if inhaled could cause permanent respiratory damage.
 
John

Derek,
 
Far be it for me to provide advice to you.  Your work is excellent and I have learnt a lot from your builds.  However, I do know a thing or two about chemical blackening since I have a chemical background.   This reaction is actually very fast so if your blackening is taking 1 minute the surface is not clean enough.  On clean surfaces 10 to 20 seconds is enough.  The advantage of a clean surface is that the minimum amount of selenium is deposited (no flaking) and a very uniform blackening results.  Have a look at this post of mine which shows an extreme case of poor blackening
 
Report post    #35 Posted August 23  
This is an example of a blackening problem which others may have experienced without knowing the reason.
 
These belaying pins were sold as being brass so on the right I used my usual technique of treating for 5 min with sodium hydrogen sulfate then blackening.  Even after about 1 min the result was poor.
On reflection they were very shiny so were probably lacquered. So on the left the treatment was: - rub with steel wool, soak in acetone for about 1 min, 5 min in sodium hydrogen sulfate then blackening. After only for 10 sec the result was excellent.
 

 
Incidentally, Sparex is just a very expensive packet of sodium hydrogen sulfate. So if you have access to the chemical itself it is much cheaper
 
John
 

Yes indeed Kurt, boiling Sparex (which is incidentally an expensive packet of sodium hydrogen sulfate) could be dangerous because once dissolved it is sulfuric acid.  It is quite dilute initially but if it becomes concentrated by boiling it will produce oxides of sulfur (chemically SO2 and SO3). These are dangerous gases and if inhaled could cause permanent respiratory damage.
 
John

Others may be interested to note that the inscription reads:
 
"Draft for building in the Marchant's Yards by contract two cutters for his Majesty’s Service to carry ten 18 pounder carronades and two 6 pounders for chase guns       
 
A copy of this draft was sent to Mr Thomas Johnstone at Dover 30 May 1806 for building two cutters named Cheerful and Surly 
 
Approved by the Lords Commissioners of the Admiralty 17 April 1806 "
 
John

Yes indeed Kurt, boiling Sparex (which is incidentally an expensive packet of sodium hydrogen sulfate) could be dangerous because once dissolved it is sulfuric acid.  It is quite dilute initially but if it becomes concentrated by boiling it will produce oxides of sulfur (chemically SO2 and SO3). These are dangerous gases and if inhaled could cause permanent respiratory damage.
 
John

Others may be interested to note that the inscription reads:
 
"Draft for building in the Marchant's Yards by contract two cutters for his Majesty’s Service to carry ten 18 pounder carronades and two 6 pounders for chase guns       
 
A copy of this draft was sent to Mr Thomas Johnstone at Dover 30 May 1806 for building two cutters named Cheerful and Surly 
 
Approved by the Lords Commissioners of the Admiralty 17 April 1806 "
 
John

Others may be interested to note that the inscription reads:
 
"Draft for building in the Marchant's Yards by contract two cutters for his Majesty’s Service to carry ten 18 pounder carronades and two 6 pounders for chase guns       
 
A copy of this draft was sent to Mr Thomas Johnstone at Dover 30 May 1806 for building two cutters named Cheerful and Surly 
 
Approved by the Lords Commissioners of the Admiralty 17 April 1806 "
 
John

Others may be interested to note that the inscription reads:
 
"Draft for building in the Marchant's Yards by contract two cutters for his Majesty’s Service to carry ten 18 pounder carronades and two 6 pounders for chase guns       
 
A copy of this draft was sent to Mr Thomas Johnstone at Dover 30 May 1806 for building two cutters named Cheerful and Surly 
 
Approved by the Lords Commissioners of the Admiralty 17 April 1806 "
 
John

Dgbot,
 
I think you might have a nomenclature problem here.   I think what you mean is salicylic acid.  By "Selinic acid" I think you mean selenic acid which is a more oxidized form of the selenium dioxide (or selenious acid) which we use to blacken brass.  Both of these chemicals are quite toxic but salicylic acid is relatively harmless.
 
John

Post 28: Timberheads
Once again Chuck describes how to make these.  I made them in pairs (oort and starboard) so that they matched as closely as possible.  I measured the angle with my digital protractor:

This got me started but in the end I eyeballed it.  It is surprising how a very small difference in angle is noticeable.

You will also notice that I have installed the scuppers. Here rather than just use a hole as indicated on the plans I used rivets to fill the holes .  These are used on electronic circuit boards and have an internal diameter of 1 mm and fit into a 1.6 mm hole. I blackened them first of course.
 

 

I actually posted this elsewhere but it is probably more appropriate here.
 
This is an example of a blackening problem which others may have experienced without knowing the reason.
 
These belaying pins were sold as being brass so on the right I used my usual technique of treating for 5 min with sodium hydrogen sulfate then blackening.  Even after about 1 min the result was poor.
On reflection they were very shiny so were probably lacquered. So on the left the treatment was: - rub with steel wool, soak in acetone for about 1 min, 5 min in sodium hydrogen sulfate then blackening. After only for 10 sec the result was excellent.
 

 
Incidentally, Sparex is just a very expensive packet of sodium hydrogen sulfate. So if you have access to the chemical itself it is much cheaper
 
John
 

Glenn,
 
I am always a bit reticent about providing any advice here as I am a rank beginner at this game.  However, for what its worth here is a picture of my scraper and the result.  I think I used the one on the left or something like it.  I made about 10 of them in the end.
 


 
The few tests that I did with yellow cedar gave very indistinct results and it was only when I used boxwood that I could obtain a satisfactory profile.  I also stuck the strip to a glass plate on my bench with double sided tape to stop it moving. I found that several light strokes were best until the profile was established and then I could be more aggressive.
 
 
 
John

Jim,
 
I placed this order a week or so ago but have not heard about the postage yet:
 
"Thanks for your on-line order #200817MM14633700 at ByrnesModelMachines.com!"
 
I am only concerned because orders from the US can take a couple of months to get to Australia and I don't want to be caught in the Christmas rush.
 
John

Jim,
 
I placed this order a week or so ago but have not heard about the postage yet:
 
"Thanks for your on-line order #200817MM14633700 at ByrnesModelMachines.com!"
 
I am only concerned because orders from the US can take a couple of months to get to Australia and I don't want to be caught in the Christmas rush.
 
John

Glenn,
 
I am always a bit reticent about providing any advice here as I am a rank beginner at this game.  However, for what its worth here is a picture of my scraper and the result.  I think I used the one on the left or something like it.  I made about 10 of them in the end.
 


 
The few tests that I did with yellow cedar gave very indistinct results and it was only when I used boxwood that I could obtain a satisfactory profile.  I also stuck the strip to a glass plate on my bench with double sided tape to stop it moving. I found that several light strokes were best until the profile was established and then I could be more aggressive.
 
 
 
John

Glenn,
 
I am always a bit reticent about providing any advice here as I am a rank beginner at this game.  However, for what its worth here is a picture of my scraper and the result.  I think I used the one on the left or something like it.  I made about 10 of them in the end.
 


 
The few tests that I did with yellow cedar gave very indistinct results and it was only when I used boxwood that I could obtain a satisfactory profile.  I also stuck the strip to a glass plate on my bench with double sided tape to stop it moving. I found that several light strokes were best until the profile was established and then I could be more aggressive.
 
 
 
John

Glenn,
 
I am always a bit reticent about providing any advice here as I am a rank beginner at this game.  However, for what its worth here is a picture of my scraper and the result.  I think I used the one on the left or something like it.  I made about 10 of them in the end.
 


 
The few tests that I did with yellow cedar gave very indistinct results and it was only when I used boxwood that I could obtain a satisfactory profile.  I also stuck the strip to a glass plate on my bench with double sided tape to stop it moving. I found that several light strokes were best until the profile was established and then I could be more aggressive.
 
 
 
John

Glenn,
 
I am always a bit reticent about providing any advice here as I am a rank beginner at this game.  However, for what its worth here is a picture of my scraper and the result.  I think I used the one on the left or something like it.  I made about 10 of them in the end.
 


 
The few tests that I did with yellow cedar gave very indistinct results and it was only when I used boxwood that I could obtain a satisfactory profile.  I also stuck the strip to a glass plate on my bench with double sided tape to stop it moving. I found that several light strokes were best until the profile was established and then I could be more aggressive.
 
 
 
John

Glenn,
 
I am always a bit reticent about providing any advice here as I am a rank beginner at this game.  However, for what its worth here is a picture of my scraper and the result.  I think I used the one on the left or something like it.  I made about 10 of them in the end.
 


 
The few tests that I did with yellow cedar gave very indistinct results and it was only when I used boxwood that I could obtain a satisfactory profile.  I also stuck the strip to a glass plate on my bench with double sided tape to stop it moving. I found that several light strokes were best until the profile was established and then I could be more aggressive.
 
 
 
John

Glenn,
 
I am always a bit reticent about providing any advice here as I am a rank beginner at this game.  However, for what its worth here is a picture of my scraper and the result.  I think I used the one on the left or something like it.  I made about 10 of them in the end.
 


 
The few tests that I did with yellow cedar gave very indistinct results and it was only when I used boxwood that I could obtain a satisfactory profile.  I also stuck the strip to a glass plate on my bench with double sided tape to stop it moving. I found that several light strokes were best until the profile was established and then I could be more aggressive.
 
 
 
John

Glenn,
 
I have these scrapers.  They are good  but I find them far too big for the scale we are working at. I used jewelers files to cut a profile into the back of a annealed hacksaw blade. I think I might have also used a jewelers saw. There are several posts on this site about this technique.
 
John
 
 

Glenn,
 
I have these scrapers.  They are good  but I find them far too big for the scale we are working at. I used jewelers files to cut a profile into the back of a annealed hacksaw blade. I think I might have also used a jewelers saw. There are several posts on this site about this technique.
 
John