DIY Photo-Etch Help?

[CRL]

Using hand tools = Less chance of catastrophic awwwwwww shiiiiit!!!!

[Maletrain]

Using hand tools = Less chance of catastrophic awwwwwww shiiiiit!!!!

Using hand tools on things that size, I tend to get some "Aw ***** -blood" events   I agree with Max about making the slot before you cut the piece out of the sheet.  You can use files on the outside of the piece.

[metalworkertom]

I was going to suggest this too, but I figured it would scare people off.  I made one of these expansion links for some valve gear once.

It's really not as bad as it seems.  Just start with some .010" thick brass strip, eyeball it into its approximate "boomerang" shape with some files, and then drill a bunch of little holes in it with a #80 or #79 drill, and use a #11 Xacto knife to pick away at the holes until you open up a nice slot in the middle of the part.  Files are way too thick to make that slot.  But a #11 blade will do the trick.

CORRECTION: You probably want to do all the drilling and picking BEFORE you cut the part out of the brass strip and start shaping it.  Much easier to work on it that way.

The circled part on the right in the photo below shows the part before I finished the slot.

Be not afraid! 
You can probably make one of these parts in a couple of hours or less, and then it will be one solid piece with no joints or soldering.

It takes practice but a jewlers saw does much better than chain drilling. You can also use the saw blade as a file.

[peteski]

It takes practice but a jewlers saw does much better than chain drilling. You can also use the saw blade as a file.

That's assuming that one even owns a jeweler's saw.  Not everybody has a well-equipped workshop.

[CRL]

Nobody owns tools of any type until they encounter a need for that specific tool. That’s how we acquire tools for that mythical well equipped tool shop.

The trick is finding the tool in your collection of tools the second time you need to use it.

[mmagliaro]

I agree, a jewelers saw would do a fine job.  They are not expensive, either (maybe $25 at a jewelery supply place like Esslinger.com)

I wonder why I don't own one?   

[metalworkertom]

I agree, a jewelers saw would do a fine job.  They are not expensive, either (maybe $25 at a jewelery supply place like Esslinger.com)

I wonder why I don't own one?   

$15 or so for a good German brand from Rio Grande. $30 if you get a blade assortment package as well.

[metalworkertom]

I was going to suggest this too, but I figured it would scare people off.  I made one of these expansion links for some valve gear once.

It's really not as bad as it seems.  Just start with some .010" thick brass strip, eyeball it into its approximate "boomerang" shape with some files, and then drill a bunch of little holes in it with a #80 or #79 drill, and use a #11 Xacto knife to pick away at the holes until you open up a nice slot in the middle of the part.  Files are way too thick to make that slot.  But a #11 blade will do the trick.

CORRECTION: You probably want to do all the drilling and picking BEFORE you cut the part out of the brass strip and start shaping it.  Much easier to work on it that way.

The circled part on the right in the photo below shows the part before I finished the slot.

Be not afraid! 
You can probably make one of these parts in a couple of hours or less, and then it will be one solid piece with no joints or soldering.

About files being to thick. To me a brand new file is a unfinished tool. Grind it down if needed. I use a lot of files all most all are modified. Safe edges ground on one or more sides. Whatever it takes to get the job done.

[mmagliaro]

Grinding down files... I have done that to make then narrower or to make other special shapes.
But oddly enough, it never occurred to be to grind down one face completely to make the whole file super-thin for work
like this.
Two great tips in one day... THANKS.

[cbroughton67]

Well, operating on a part that small, I wasn't sure that soldering would work, but it did. I've reassembled the locomotive, corrected the position of the eccentric crank and re-brazed it, made a few adjustments, and it's running as smooth as silk, now. Thanks to everyone for the ideas and encouragement! Now, time to add a working headlight, sound, and a keep-alive!


Thanks again,
Chris

[CRL]

As long as you can clamp the sheet stock, you can use a narrow strip of emery cloth to work down the inside edges of the slot to get them smooth.

[mmagliaro]

As long as you can clamp the sheet stock, you can use a narrow strip of emery cloth to work down the inside edges of the slot to get them smooth.

I agree.  I've done that with 400 or 800 grit sandpaper, cut into really narrow strips with a steel straight edge and a #11 Xacto (like 1/16" wide strips or even narrower) to clean out little passages and slots like that.  Parts that small can still be easily clamped in a jeweler's vise like the Panavise.

[Lemosteam]

Or a small diameter diamond burr in a slow rpm drill...

[randgust]

But this is still a happy ending under 'quit debating and start fabricating....' and that's a good thing.