Help, please: When to put in wire inlay

[Bill Ellis]

I probably deserve to get laughed at for asking this question, but I guess I can say that I was drinking or something when I posted it if it begins to haunt me.

I am going to make a damascus straight razor that has an inch wide blade that is 3/16'ths of an inch thick. I want a simple border of wire inlay on the tang and a small gold/brass celtic do-dad about 2 inches long on top of the spine. Here's my question:

I know that I need to cut the channel for the wire before heat treat, but at what stage do I add the wire? Before or after the heat treating? The steel will be heated to about 1,600 degrees for ten minutes + or - and then tempered at about 400 for a few hours.

If I add a border to the top of the spine (3/16'ths inch wide), what wire size should I use? I may have to use brass instead of gold, but I can make that decision later. I have a draw plate to size the wire.

Here is the steel that will need a bit of work first.

 

[JBrandvik]

Bill, you should get the channel prepared (cut and undercut)before heat treating and tempering, then apply the gold after. When you are preparing the channel try not to raise the edge up around the channel as it will be a bear to smooth out after heating treating and tempering and you would run the risk of either tearing -out the gold or eroding it below the steel's surface so that its not flush.

This is a great idea. I can't wait to see more of this project.

Best,

 

[John B.]

Bill,
You would have no problem completing the inlay before heat treating at 1600 degrees F.
If you are using 22-24 KT gold.
We very often color case guns that are inlaid and the heat is 1800 degrees, no problems.
Just leave the fine cut detail on the gold surface 'till after heat treat.
It can get banged or rubbed during the process and need to be touched up.
No sense in having to cut it twice.
Best wishes,


PS. You can do it the way Jim suggests. Just undercut while in the soft state.
Where the edges are raised up from undercutting sand or stone them before heat treat.
This is not my favorite way to do it, you can have some heat treat scale remaining under the gold
in the bottom of the channel.

 

[jerrywh]

Very important info----- I do a lot of gold work and case hardening. 24k gold normally melts at about 1880° fer. But when packed in charcoal it melts at about 1525 to 1550. The thinner the gold the lower it will melt when packed in charcoal. WHY? I personally think the carbon changes the molecular structure of the gold into a sort of alloy like carbon changes iron into steel. However no matter what the reason I know what I am talking about. I have had to do some work over for that reason too many times. If the part is not packed in charcoal the gold will stand the normal temp. unless it is in contact with some other types of metal such as lead or tin. If gold is in contact with tin or lead it will alloy with the lower melting metal at the lower melting metal's normal melting temp. This is the reason gold is never soft soldered. I know. believe me.
Also remember--those inlays will have to be sanded down after they are installed or sculpted. I recomend doing the gold first but hold your heat treating temp down to 1550 if they are pack hardened in charcoal. I don't mean to be contentious John. but color hardening is never done at 1800° If the temp exceeds 1550° you will begin to loose the colors and come out plain gray. If the temp exceeds about 1650 or 1700 the surface will take on a grainy look. like orange peal.
The screws in the photo below were color case hardened and then heat blued. the gold is .003 thick.

 

[Kevin P.]

Bill, sounds like a very cool thing. Please use gold, your work is too valuable for brass unless there are other considerations.
Love to see it when you're finished.
Kevin P.

 

[Bill Ellis]

Bill, sounds like a very cool thing. Please use gold, your work is too valuable for brass unless there are other considerations.
Love to see it when you're finished.
Kevin P.

Although my razors and knives are good, my engraving needs a lot of practice to match them. I just didn't want to act like my engraving skills were good enough for gold yet. However, since the damascus I bought for the project is expensive as well... what the heck, right?

Thanks for the responses. I will try to update the saga with pics as the project progresses. I do have the blade profiled, tang tapered and master grind close to being finished. At least for the stage before heat treat. I have to leave the blade thicker until after heat treat, otherwise the cutting edge will look like the bottom fin of an electric eel. When it's tempered, I'll finish grinding the blade.

I know that there is probably a reference here somewhere about sources for gold wire, so I will look for it rather than take the lazy route of asking about it here.

I will also be looking for tips on how to keep wire in a channel cut by a #37 GRS flat graver. Don't hit me... I'm assuming that would be the one to use to match the small area on a tang and on top of a 3/16 inch wide spine?????

 

[Marcus Hunt]

Also remember--those inlays will have to be sanded down after they are installed or sculpted.

Can you please explain? As a gun engraver, once the inlay is in that's it. It shouldn't need sanding or sculpting after case hardening unless it's accidentally damaged in some way.

 

[Kevin P.]

DH Fell in CA and Hoover & Strong in VA for your gold needs. Google for details.
Kevin P.

 

[Tim Wells]

Rio Grande also has gold wire as does Ray Viramontez (I think I spelled that right) in South Georgia.

Marcus,
I think what he's referring to is the necessity to flatten the inlay after the gold is pounded in along with the resultant "raised lip" formed when doing the undercut around the edges of the prepared channel. At least that's the way I read it.

 

[Tim Wells]

Not to get off topic but I was wondering since you have the master grind done already; how do you keep the blade blank from warping when it gets cooked? Seems like a blade that thin would warp badly in an oven. I'm getting educated here.

 

[BrianPowley]

FWIT....You might want to avoid brass as an inlay material.
I've found that the extra time (and frustration) it takes to inlay the brass makes the cost of gold a real bargain.

 

[jerrywh]

Marcus.
What I was referring to was --- if he case hardens the part before putting in the gold, then when he puts the gold in he will have to take the gold down flush of trim it. This will mar the surface of his part some. If he does the gold inlay before hardening -- no problem.
Bill.
when using 24k gold there is no need to cut a groove with vertical sides wit ha flat graver, you can just use a regular square graver and undercut the sides in the conventional way. from the sides with a chisel. Personally- I only cut a vertical channel for iron inlays or very hard metal.
Look back thru the posts or tutorials on this forum and you will find some very good info on gold inlay work.

 

[Bill Ellis]

Not to get off topic but I was wondering since you have the master grind done already; how do you keep the blade blank from warping when it gets cooked? Seems like a blade that thin would warp badly in an oven. I'm getting educated here.

My apology. I thought I might have made it understandable in my second paragraph of post #6.

I leave the cutting edge thick at around .040. After heat treat, I grind it down slowly with new belts to .010 or thinner. I shoot for .008 at the edge. The sad part to all that is that I cannot engrave anything on the blade itself because subsequent grinding after heat treat would take it all off.

 

[JBrandvik]

Bill, I should have added that with my application being horseshoes, I am using a torch to heat-treat solely for the purpose of keeping the rust problem at bay. I have made some messes by trying this after the gold was in.

This thread (and John's seperate thread about inlay and heat) has taught me a lot. I bow to the knowledge and experience of others and withdraw my sugestion. I will asking to borrow the use my knifemaker buddies ovens in the future.

Best,

 

[John B.]

Friend Jim B.
Nothing wrong with your method for your purpose for rust prevention on your horseshoes.
Removing the color case colors and not the case hardened surface under it leaves the piece in the white.
Often called a coin finish and provides a pretty good rust resistant finish.
I know you know all this but some others may not.
Hope the shoes are doing well for you, Cowboy.

Best regards always.

 

[JBrandvik]

John,

Thanks for helping me pull my foot out of my mouth but I don't have any trouble admitting when I'm wrong. (I get lots of practise being wrong.) I would rather heat treat with the gold in place for all the reasons you and others have mentioned. After fowling up some inlays, I figured everybody did it this way. I would guess my troubles came from not being able to accurately judge the amount of heat (I mean what color is "Straw" really?) I have access to a friend's heat-treating oven and I am looking forward to doing it an easier way.

Best,

 

[Kevin P.]

Sam, it would be great if this thread could be included in 'tips' or 'tutorials'.
This is very interesting and most of it totally new to me and probably some others.
Kevin P.

 

[Bill Ellis]

Thanks for the advice to all of you. I will try to put in the gold before heat treat. I have some 24K coming from Rio Grande. In the meantime, I will try not to mess things up. Here is a pic of the blade in the condition that I will heat treat it. The blade is about 20mm wide (I noticed that mm's seem to be preferred here instead of inches) and the thickness of the blade is about 5mm.

Right behind the blade where the hump and tail is, that's called the tang and it's where I want to put the border around. I was thinking about 1.5mm from the edges on the outline of the tang. Yes? No? The tail of the tang narrows down to about 7mm.

I know this stuff probably is very simple to you guys, but it scares me to death.

 

[John B.]

Bill, Sounds good to me, nice looking razor.
Does it get a hole for a pin to hinge it open?
Have you given any thought to putting a little open scroll or leaf to end you line at the hump end?
Like the good old flag background for Flag Day, nice touch.

Best.

 

[Bama]

Bill this is a question and not a comment. I have never done any work with damascus steel so I am asking this for education. It is my understanding that for damascus pattern to show up that the steel is givin a acid bath, is this correct? If so does this happen before or after heat treating the steel and will the acid have any effect on the inlay work?