few questions: Fixed blade stuff.. Canvas Micarta, Corby bolts, tubing.. help

Work765

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OK,, so.. last weekend I tried my hand at Corby Bolts, Canvas Micarta, and Tubing for a lanyard hole in the back on some fixed blades..

This was my first time using Canvas Micarta, and when grinding the Corby's I kept on burning the Micarta, and it left a small black ring out the bolts.. (i was dipping it in the water frequently too)

My usual method for doing pins is glue one side, then drill holes, and then glue the other side, and then drill.. and put pins in when im done with the handles,, and hammer and grind down.. Presto..

but with the corbys.. I tried the same thing, and when making the larger diameter opening, i slightly hit the handle at an angle and the corby didnt sit in perfect.... No worries.. I figure next time.. drill down the larger diameter before I start shaping the handles, so that its completely flat... Also, I was just using the next bit size, up and it seemed like there was room for error when making the hole.. There is a bit that has a step down or up, that you guys use, so it aligns perfectly?

Also you guys always put locktite on the corbys right?

now to the lanyard hole.. I had the holes drilled and went to put in the hollow tubing and it needed to be hammered a bit, and on two separate knives the handles came unglued!! .. basically it was a disaster this weekend for knife building..


What am I doing wrong? how do i put in hollow tubing and not worry about my handles popping off... and how do i not burn up my canvas micarta? and the corby issues...

any help would be great.. sorry this is long winded.. I just want to do it right next time..
 
1. Use a fresh coarse grit belt on the Corby bolts and keep things cool.

2. Insofar as pins go: Use bolts and a Corby bolt specific step drill.

3. Have fun

4. Glue is glue and a mechanical connection is a mechanical connection. Bolts are mechanical connections that I consider to be permanent connections - they don't "pop off". Use permanent connections and not temporary connections.

5. Flare the tube and turn it into a mechanical connection that I guarantee will not "pop off".

6. Have fun

Jeff

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I lay out the holes on the tang and then drill them the same size as the sleeve on the female side of the Corby. Then I glue one scale blank on one side, let the epoxy set and drill the scale the same size using the scale as the template. Then I glue the second scale blank on the other side of the tang, let the epoxy set, and drill the hole through from the other side. Then I switch to the step drill for that size Corby and drill the wholes in the scales larger part way to seat the heads of the bolts in. I then put a drop of epoxy on the male threads and tighten them together. It's also a good idea to dry fit the bolts before doing this. Let the epoxy sit and carefully grind the heads of the bolts down and shape the handle. I also find that it's better to not taper the tang when using bolts.

Doug
 
What Bush Monkey and Doug said!
To avoid burning your handle material when grinding down your corbys, First either file or saw the tops down close to flush with the handle material so there is less grinding needed to bring them down completely flush. The same strategy works for most types of pins and fasteners.
 
As George mentioned: cut the bolts off close to minimize
heat when grinding flush. I assumed you were doing this but maybe not.
 
thanks guys. No I hadn't cut the corby's down.. I basically was grinding them down the hole way. But I will try the File way.. thats sounds like a good idea.

Regarding the Lanyard hole, how are you guys putting those in? I drilled to the proper size and then had to hammer it in cause it was too snug.. and the handle popped off on the other side...

Also, Bush Monkey.. Im all for flaring hollow tubing, but dont have a press yet. I need to look into that.

OK, so im buying a step down bit, and plan to file down the Corby till close to the handle.. and use fresh belts..
 
Another question.. sorry

but are you guys hitting the blade part that touches the handles with like a 60grit before gluing? to give something for the glue to adhere to?
 
Another question.. sorry

but are you guys hitting the blade part that touches the handles with like a 60grit before gluing? to give something for the glue to adhere to?
 
I sandblast all mating surfaces then bolt things together. Anything that increases the surface area of the bond is better than nothing. If you are pinning and gluing things together, the bond is critical to the integrity of the knife. If you are bolting things together, the epoxy is just a sealer.
 
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Another question.. sorry

but are you guys hitting the blade part that touches the handles with like a 60grit before gluing? to give something for the glue to adhere to?

I flat sand scales at 120 grit and then use 60 grit on the edge of my 2" wheel to rough the center.
I agree with Jeff of bush monkey that bolts are the way to go and use mostly Loveless style. Epoxy is also important as it helps seal out moisture as well as increases your overall bond. so rough yout truly flat scales and use a slow cure epoxy along with using a moderate clamping pressure so you don't squeeze out all of the epoxy.
 
I do the same as Laurence. but rough the tang and scales up with a 36 grit belt...:)

Regarding the Lanyard hole, how are you guys putting those in? I drilled to the proper size and then had to hammer it in cause it was too snug.. and the handle popped off on the other side...

Ideally you want to use a drill bit that is a few thousandths larger than your laynard tubing or pins. This is were number and letter size bits come in handy. For a 1/8"(.125") diameter pin I use a number 30 size bit (.128"), the slightly over-sized hole gives the epoxy somewhere to go, makes it easier to insert the pins, and will be invisible once the handle is finished.

Also, for flared laynard hole tubes, you will want to countersink the hole so that when the tube is flared it has somewhere to go...
 
Yes, it's a good idea to grind/sand the leading edge of the scales before all the gluing and drilling to keep from hitting the blade/racisso. I use double stick tape to hold the scale blanks together and even on the leading end. You can even use the tape to hold the scale blanks together as you cut a radius with a saw if you want one. Just take care to glue them up evenly when you put them on the tang.

Doug
 
Here's my method. I drill the holes in the knife blank just large enough for my small OD on the corby. I use the holes in my knife blank to line up where to drill my holes in the handle material. To do this I place the handle material on a piece of wood in my drill vise, then place the knife blank on top of that. Next drill one hole the same size as the one in the knife blank. Next I flip the scale over and use the rivet drill of appropriate size. It drills and countersinks in one step. Only take it as far as you need to. Then I use the corby to perfectly align my scale and knife blank and drill the next hole. I repeat this method until all holes are drilled and countersunk for the corby bolts. Then bolt the scales with the corbys and use the grinder to take the handle scales down to my profile of the knife blank. Then unbolt and work the front of the scales near the ricasso. You can't really work them after gluing so do it before. Glue the scales, let cure, cut down bolts, profile scales to a comfortable grip. I haven't had an alignment issue in the 10 or so knives that I have made.
 
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Do you guys have a good online source for the Stepdown bits and the Letter size Drill bits? USAknife maker didn't have the step down or or the letter "V"..

Also, do any of you guys have the 1 ton harbor freight press that USA knife maker sells? its tapped and ready to receive there flaring dies... I bought the dies, but wanted to look around before I bought the press... Wasn't sure if i should get a bigger one, or one that isn't tapped.. I'll search the forums a bit too for info..
 
Laurence,

thanks! I think we might have spoken on USN before.. I live in Santa Monica. Im going to come down to your shop on 4th soon!!
 
Jantz carries step bits for the various size bolts and rivets that they stock. The also carry standard, metric, letter, and number drill bits.

Doug
 
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