[Roy_Burns]

Making scales/grips for a tool. The butt end will have a full radius that is approximately 3/4". Radius will vary slightly due to the 1 1/2" stock being trimmed to fit the width of the tang. Tang will be die cut and I don't have my dies yet. They will be made to cut slightly under 1.5

After rad is cut, will be using a piloted corner rounder to put a .25 rad around the outside of the scale.

Need to build a jig that is slightly adjustable to do this.

See attached sketch.

 

[Cherryville Chuck]

Roy, a 1.5" think scale is a bit uncommon for thickness. Make sure you want it that thick because 1.25 is probably the max. Now the next revelation is that most of those type items in olden times were hand carved and I still do that to most of those type things I do. I've found that there are no time savings to be had between doing the work by hand and building what could be complex jigs to do the same thing. PROVIDING that you aren't planning on making many of the same thing. If that is what you are planning then a little more information would be good as to exactly what the end use is going to be.

 

[Roy_Burns]

Scale is .25 thick, 4.25 long, 1.5 wide. Tang is .375 thick, so total stack with two scales is .875, that thickness works well in my hand.

Will be making many. I'm tooling up for production. Hope to make thousands one day. (Preferably with a CNC mill by then.) Bought my router table for this purpose and have no problem even drilling into the table to modify it for only making these.

Unable to go into much detail about the rest of the tool but I'm making a handle similar to a butcher knife or paint scraper.

 

[JOAT]

I'm tooling up for production. Hope to make thousands one day.QUOTE]

Ah, but will there be a market for them? I'm with Chuck, something like that, I'd rather do it myself.

 

[sunnybob]

I would just use a roundover bit with the router mounted in the table, and do it by hand.. the metal centre will give the pilot (or bearing) a reference point to make the curve fit exactly. Made in batches it would be reasonably efficient.

any "adjustable" jig would need more time to adjust than doing it by hand and eye would.

 

[Cherryville Chuck]

I agree with Bob. Use the tang for a bearing guided bit on a table. Go with a 1/4" radius bit max but a smaller one might be more pleasing. There is a difference between a paint scraper and a knife. A knife has almost solely downward pressure whereas a scraper has mostly forward pressure. Too small a bearing surface at the rear for your hand on the scraper could be uncomfortable but on a knife would be almost inconsequential. Don't underestimate the speed of doing some operations by hand. The difference is mass produced vs artisan quality. Here's an example : LIOGIER, râpes et rifloirs piqués main pour le bois et la pierre : des outils pour sculpteurs, modeleurs, luthiers, ébénistes d'art, restaurateurs de meubles et d'oeuvre d'art, etc. Look for this on the page: Cette courte vidéo vous permettra d’avoir un aperçu de notre savoir-faire de fabricant de râpes et rifloirs: my best translation of that is : "This short video will permit you to see what how we fabricate our rasps". It's in french but you'll get the idea. Noel Liogier is a member of our forum by the way. I think he is 4th generation at the business.

 

[Roy_Burns]

sunnybob- Hmmm. While the tang isn't metal, it would be pretty easy to cut a steel template and bolt the scale to it. Have to figure out a way to cut the .75 rad perfect once. Wish I had a rotary milling vise. Template wouldn't be adjustable. So I'd need to wait until I have my dies to measure the tang width. This will work.

So finish 1.5 width and square end of stock. Put scale in drill jig then csk it. Bolt on template and add corner radius. Cut the 30deg angle at some point as well. Batched, I'll only have a couple minutes in each scale.

Thanks!

Chuck- It should be pretty easy to vary the corner radius size if .25 doesn't feel good. Good suggestion, likely will play with it.

Those are beautiful rasps. Can't watch the video as flash doesn't play on my phone. I'm guessing they hand chisel the pattern into the annealed steel? Read that files were once produced this way.

Recently took up whittling and carving. Was playing with acrylic resin and it led me to the ideas I'm working on now. There's also something to be said for the beauty of a Starrett satin chrome mic or the curves of WWII iron.

There will be high finish and some customization on my tools. Uniformity and efficiency are major considerations as well.

 

[MEBCWD]

Roy,

A small CNC like the Piranha or Axiom AutoRoute 1 Hobby could cutout several scales at a time and round over the edges. I do know that getting to that point will take time. If you want to make thousands one day you will probably need a larger CNC . For these handles you won't need a large heavy machine, a hobby class machine should work for you.

For now you might check around and see if there are any local hobby CNC owners willing to cut some for you. Check with local woodworking clubs to see if there are any one interested. Also check with the woodworking stores to see if they have someone that does this type of work on the side. You supply the materials and they cut the handles, you do the cleanup on the parts.

If you still want to make them with a jig I would use a disk sander for the radius and make a jig that indexes the part to the jig. It will take time to design and build the jig but you will be able to make several quickly and repeatably. Then I would also make templates for routing the round over. You might have to stabilize the scales to prevent tear out before you route them. The stabilizing would also help condition the wood and seal the grain so it would not soak up moisture and chemicals, possibly causing the scales to crack. This could also be a selling point about quality of craftsmanship.

Put some of you profits away to purchase a CNC at a later date.

Let us know of your progress into this project and if you have questions don't hesitate to ask. Remember the more opinions we give the more choices you have.