Trapper Restoration Question

[CharlieR]

I have recently picked up an old Case Trapper and wanted to restore it...with mods. I was going to make a one blade knife as one of the blades is broken......My problem is this--when I fit my bolster pins to the bolster, the hole in the blade is larger than the pin diameter. SO, do I drill the bolsters out to the same size as the hole in the blade or not? My first inclination is drill out the bolsters, but not sure. Advice always appreciated from you guys. Charlie

[glennbad]

I believe the difference in size on the hole in the blade is to allow the blade to "slip" while on the pivot. I have never had to alter the holes of the blades on any of my reno's. I do end up altering the spring pin holes quite alot, but not the blade hole. You should not have to enlarge the bolster holes to the same size as the blade pin hole. Usually, your bolster hole will be dictated by your pin size.

I hope that makes sense.

BTW, be sure to share some pics of your finished product.

Glenn

[Joe Dirt]

I've been going with about .015 larger hole in the blade than the pin.
It IS possible to peen the pin so tight that it will rotate with the blade!

...... Joe

[knives-are-quiet]

The pivot hole in the blade should be the same size as the bolster on antique knives.
The hole in your blade may have worn larger from repeated opening and closing and lack of maintenance. Drill the bolster hole the same size or replace the blade with one that hasn't been worn as much.
You will have to work a pin down for a custom fit if you make the holes match.
All pins in a knife should fit snug with no play.
Play in the blade pivot hole will cause vertical movement in the blade in no time at all.
J W

[Elvis]

Looks like you're getting some conflicting answers. Rather than take sides, I'll offer to send you a bronze bushing and the nickel-silver pin stock of the correct size for the job. You can visit Boseknives.com (I think) and Tony Bose has a tutorial on how to use pivot bushings. It's a pretty good system and fool-proof with a few simple rules. Just drop me a PM if you want to try it.

[orvet]

Based on my experience, I agree with Joe and Glenn.

In most of the older knives I have repaired, I find the hole in the blade is a few thousands larger than the pin, which allows the blade to pivot freely. On most of the knives I have taken apart I have not observed any noticeable evidence of wear to the pivot pin.
Since most of the knives from the 1950s and later use nickel silver pivot pins, (which is much softer than the steel of the blade), I would expect the pin to wear as opposed to the pivot hole in the blade.

The only time I would expect to see wear on the pivot hole would be if there was a steel pivot pin. Even then I would think the pin would be much softer than the blade so that it could be peened.

When I was starting to repair knives I used a pivot pin that was the same size as the pivot hole. After I peened the pin into the bolsters the pin has swelled just enough in the middle that the blade was very stiff to open.

Bob (Elvis) does offer a very workable alternative, and Tony Bose makes some excellent knives!

[CharlieR]

Elvis-pm sent--thanks for the generous offer.

The knife , as I said, was an old Case trapper---the hole in the blade appears to be .119/.120 while the bolster holes are around .110.... is this normal wear?

Anyway, will try to figure out picture process and send when completed. Again, this forum is full fo great folks willing to help us beginners. Charlie

[muskrat man]

Case trappers almost always in my experience have bigger holes in the tangs than bolsters. My theory for this is when they use their press to mash the pins it spreads the diameter of the pin, if the hole in the blade was the same diameter as the pin this would cause the blade to not pivot. I have never had problems, just use the biggest pin I can get through the bolster hole, peen it real good and you're good to go, no real need to go through any additional steps.

[orvet]

I agree Kaleb. Good advice.

[knives-are-quiet]

All knife manufacturers construct knives differently.
You learn something new every day on this site.
If I ever decide to work on a CASE knife, I'll know what to do.
Most of the knives I've worked on are handmade antiques where most every knife is different.

J W