I need some help peening 1/8" SS pins..

C

coldsteelburns

Joined
Aug 2, 2010
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Hey guys, I know this topic has been discussed multiple times in the past, but I have been searching for a while trying to get a clear explanation on how it's done and can really find any. I have used the bladeforums google search engine and read a number of threads as well as just plain google searched and read some more, however none of them quite helped me with the questions that Iam having.

What I am doing is re-handling an older, fairly cheap kitchen knife that has some sintimental value and the gentleman just plain likes using it :) It's one of those typical kitchen knives with the cheap wooden handle falling apart and the cutler rivets comming loose etc. (but it's made in Japan ;) )

So I'm not doing anything fancy, but he does want the handle to be a bit longer, so I'm making the handle cover the tang by doing a "frame" handle type deal but using a piece of G10 the same thickness on the tang as the "frame" so I can have the handle extend just a little further back. It's a pretty slim blade and handle (tang)..

--------------------------------------------Actual Questions Below-----------------------------------

Ok, so anyway, I really don't want to just rely on epoxy (g flex) to keep the handle on and I already have the ironwood scales and G10 "frame" shaped and drilled for three 1/8" inch stainless steel pins.

So my question is how do I go about peening the pins without doming them? Can they be more upset instead of just spreading a very small portion of the very top?

I have read some guys epoxy the handle using temp pins, then take them out, shape the handle 90%-ish, then slightly countersink the pin holes and peen until the countersunk portion is "filled" with the pin material.

The thing is, this 1/8" is pretty hard material to peen, I've practiced on to scrap wood and was able to dome them, but that's not what I wan't.

I was wondering if if I can just slightly taper the holes in the wood on each side using someing like a small rounch tapered needle file (since I don't have any tapered reamers) so that it forms an hourglass type shape, and then do more of an upsetting of the pins so they are more wedged in there as opposed to a dome, which is the way I believe bolsters are held on.. (never done bolsters either)

Also if the above technique of upsetting won't work, how do I know what diameter to courtersink the holes with and how deep to go, and how much of the pin head to expose. I obviously don't want the pins to look way out of round and I don't want them to crack etc... I would probably be using a larger diameter drill bit to contersint since I don't have a proper one, though I do have a number of different sets of stepped bits.

Anyway, I would really appreciate any and all help regarding this as I plan on doin this on all of my knives in the future, so I can have a mechanical fastener. And I don't like corby bolts since I like using smaller diameter pins on even my larger, thicker handled knives and the 1/8" corbys have threads that are very short, pluss they are $$ and I just don't wanna mees with them lol. But that's besides the point, I really want to learn how to do this with SS pinstock so I can make my all my future handles look as If I just epoxied in the pins and ground them flush, but I wan;t the added benefit on the mechanical fastener.. Is this realistic, or should I plan on gettin some 1/8" nickel silver pinstock since it's easier to "squish" or something :confused:

*Note - I am aware that peening stuff like micarta & G10 is more forgiving than natural materials such as wood & ivory etc. So I'm not sure if this means I should only use a certain method of peening with wood that would make it less prone to splitting over time, or even during the peening process, but still be able to use a number of methods using man made materials...

Thanks for any and all help once again fellas :) :thumbup:

~Paul
My YT Channel Lsubslimed
 
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Never try to "upset" pins. Forget the term "squish" and substitute the term "head."

Peen a slight head on them by using gentle taps with a (very) small hammer. You can file/grind them flush if you want. A slight chamfer is all you need on your holes. Leave about 1/16" of the pin exposed on both sides before you peen.

Brass or nickel silver is much easier to peen than stainless.
 
OK thanks :) I have read Murray Carter explain doing something like the "hour glass" method that I described above on all his neck knives, but I'm not sure how he really goes about it, which is why I brought that up. lol I didn't quite mean "squish", just upsetting more of the pin than just doming the very top of the head and grinding it off.

So is that the only way? Shape the handle pretty much all of the way the peen the head, which in turn leave slight dome wich can be ground flush?

I guess I'm cunfused "how" much peening needs to be done to actually create a solid mechanical fastener.. I just keep imagining a very very thin portion of the head of the pin that has been spread (peened) only remaining after grinding flush.

So the tapered reamer (I would use a tapered round needle file) way will not work? Only making a slight counter sink and filling it with a slight "mushroom" will work, or?

(I like the idea of the two sides of the pins being more "wedged" a bit on each side in a taperd hole, as opposeed to having a thin flashing od "nail head" type peened pin..)

I know these must seem like basic questions, but I've never looked into all this until recently. like how deep, and how big (diameter) countersink do ya make? Is it more like a slight chamfer, or do you go a bit deeper with a drill bit that is like barely oversized to makes something more of a counterbore, like maybe about as deep as the diameter of the pin (ie like 1/8" counterbore foir 1/8" pin, or something along those lines)? I guess what is a good rule of thumb for depth and diameter of counerbore, if of course it can be properly peened in that manner?

Thanks again :)

~Paul
My YT Channel Lsubslimed
 
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Any explanation will make you only more confused, trust me it's easy:
Take a piece of scrap and drill an hole (make it so the pin is square and snug to begin with), then peen a pin on it for testing...you will need just way-less-than-you-think hour glass shape, and a needle file will take you home with a couple of strokes.
Don't ask the pin to fill more space than it can.
In the end grind flush....that's it, and when you get a grip on the technique do the same on your knife.
 
3/16" ( or other size) Corby bolts will make this problem have a simple and rock solid solution.
 
Stacy E. Apelt - Bladesmith said:
3/16" ( or other size) Corby bolts will make this problem have a simple and rock solid solution.
Click to expand...

True, but I don't like using above 1/8" pins on most of my knives, and the corby's cost quite a bit more and from looking at supply site frequently they seem like they can be a PITA to get the material and size you want if you need to get more stock. The 1/8" corby's aren't long enough for more robust handles either. Although, I've just recently seen new 1/8" ones with extended threads, but those are probably sold out by now (everything at usaknifemakers (which is where I saw them) seems to always be sold out lol).

Anyway, I was just wondering if someone could help me out with how to go about peening pins, since I know there are plently of makers that do it. I was mainly wondering if the "only" way to "peen them was to peen just the head to it fills a slight over sized area about the drilled pin hole, as opposed to being able to have a bit more of a wedge effect with a slight hourglass shape, using some like a tapered reamer about a third of the way through each scale's pin holes. Aso I don't know how to go about preparing the pin holes in order to peen them the normal (non hourglass) way... slightly chamfer? slightly counterbore? how much more in diameter than the pin hole do you countersink or counterbore at, and how deep etc.?



Thanks again :)

~Paul
My YT Channel Lsubslimed
 
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The hourglass shape can be done effectively on very short pins. Think of it as two peened heads close together. Long pins will bend before they spread like that.
You just need to practice on scraps until you understand the process.
 
just try... take a tapered reamer and ream by hand only 1,5 mm of the hole depth if the surface of the scale is pretty much finished. You dont' want to grind away the shallow chamfer during finishing.
 
A second suggestion if you are having trouble peening the heads on stainless pins is to switch to nickel pins. Nickel silver hammers much easier.

As for the cost of Corby bolts, I don't consider an extra $3-4 per knife as a great expense...especially when it makes handle assembly and security a done deal. If you want a "robust handle" you can never beat a Corby.
 
Do you have to peen when the epoxy is still wet or do you clamp and let the epoxy dry then come back and peen?
 
Drill your holes, stick an appropriate sized tapered pin reamer in, give a couple of good twists, and then pop your pin in and peen. It really doesn't take as much as you might think for a good mechanical bond. If you don't like proud or domed pins, just file or grind the pins flush.

Don't think it will be strong enough? Practice on a couple pieces of scrap sandwiched together. Peen a pin as described above, and then try to pull it apart. No glue, just a pin. It's a lot harder than you think, if done right, and it really doesn't take much of a peen/hourglass.
 
Do you know what type of stainless it is ? Is it annealed ?
I've annealed brass for instance which most people think is soft .But fully annealed it's much better. Stainless of course will be much harder regardless of being annealed .
A little bit of peening will go a long way.
 
There has been a lot of quality info posted here on this topic over the years. Everyone has their own way it seems, but nothing beats practice with your own gear and your chosen materials IMHO.

Here is a knife I am working on now in 1/8" CPM 10V (my thanks to Darrin Sanders). The handle is Desert Ironwood slabs with 3 X 3/32" 416 SS pins. These pins are peened just to the point that any lateral movement is stopped. The holes were bored nominal from original 1/16" pilots and pins were carefully prepped for length (handle width at that pin hole plus one pin diameter or so) and for point shape. Spinning pins against a file takes just a minute to form the tapers and this has given me more consistent behavior once the hammer comes out.

IHSev3c.jpg


I want to believe that central point gets driven down into pin head during initial peening and offers to fill the hole and keep a round cross section, even on non parallel slab contours, better than squared-off heads. I lightly coat the pin and hole with GFlex epoxy and wipe off run out before tapping pins (used as a sealant more than anything). I peen with a 4 oz hammer and use a lot of fast light taps while flipping regularly on anvil face to keep pin centered till it locks up. I press proud heads down hard on the anvil to test for elimination of side-to-side movement. No point in going further and risking cracked slab material.

5ZfH2JK.jpg


This is what I shoot for. Done this way, the button head forms mostly above the slab as it swells and not "in" the slab. These heads can be either filed off flush or domed with a polished punch around the edges if that's your thing. I like to use a small sharp mill file because it keeps the pins cool and preserves the flush geometry better than the alternatives I've tried.

oVVDazY.jpg


I have tried to take one of these apart before and found there was no way to do it without grinding out the pin heads first. I believe they are much stronger than they need to be for the average/user knife.

This is what it looks like before final shaping and polishing. No gaps or epoxy halos and all pin heads are uniformly round with very similar diameters.

PViWcs0.jpg


I also use nickel silver and brass on demand, but prefer 416 stainless. My experience is that annealed SS is not that much more difficult to peen well than either of those materials. They all tend to work harden as they move but this approach to peening sidesteps that problem through careful measurement and material prep up front.

Apologies to all for the unwieldy pic sizes; I'll get this part figured out one day...

Here's a link to another post with good information.

http://www.bladeforums.com/forums/showthread.php/1141791-Hammers-pins-and-peening

BTW for the observant, Burt has given me his blessing on this one. Great pattern.
 
Very nice, I will have to try this method. Thank you
 
Interesting.

So, you are gluing your handle on first. Then shaping it, then putting the pins in.

I thought you put the pins in, at the same time you epoxy the handle on.

I like your way better. Probably use 1/2 the pin stock.

Andy Lewis said:
There has been a lot of quality info posted here on this topic over the years. Everyone has their own way it seems, but nothing beats practice with your own gear and your chosen materials IMHO.

Here is a knife I am working on now in 1/8" CPM 10V (my thanks to Darrin Sanders). The handle is Desert Ironwood slabs with 3 X 3/32" 416 SS pins. These pins are peened just to the point that any lateral movement is stopped. The holes were bored nominal from original 1/16" pilots and pins were carefully prepped for length (handle width at that pin hole plus one pin diameter or so) and for point shape. Spinning pins against a file takes just a minute to form the tapers and this has given me more consistent behavior once the hammer comes out.

IHSev3c.jpg


I want to believe that central point gets driven down into pin head during initial peening and offers to fill the hole and keep a round cross section, even on non parallel slab contours, better than squared-off heads. I lightly coat the pin and hole with GFlex epoxy and wipe off run out before tapping pins (used as a sealant more than anything). I peen with a 4 oz hammer and use a lot of fast light taps while flipping regularly on anvil face to keep pin centered till it locks up. I press proud heads down hard on the anvil to test for elimination of side-to-side movement. No point in going further and risking cracked slab material.

5ZfH2JK.jpg


This is what I shoot for. Done this way, the button head forms mostly above the slab as it swells and not "in" the slab. These heads can be either filed off flush or domed with a polished punch around the edges if that's your thing. I like to use a small sharp mill file because it keeps the pins cool and preserves the flush geometry better than the alternatives I've tried.

oVVDazY.jpg


I have tried to take one of these apart before and found there was no way to do it without grinding out the pin heads first. I believe they are much stronger than they need to be for the average/user knife.

This is what it looks like before final shaping and polishing. No gaps or epoxy halos and all pin heads are uniformly round with very similar diameters.

PViWcs0.jpg


I also use nickel silver and brass on demand, but prefer 416 stainless. My experience is that annealed SS is not that much more difficult to peen well than either of those materials. They all tend to work harden as they move but this approach to peening sidesteps that problem through careful measurement and material prep up front.

Apologies to all for the unwieldy pic sizes; I'll get this part figured out one day...

Here's a link to another post with good information.

http://www.bladeforums.com/forums/showthread.php/1141791-Hammers-pins-and-peening

BTW for the observant, Burt has given me his blessing on this one. Great pattern.
Click to expand...
 
I do most all of my knives that way.
One thing that helps a lot is to first flatten both ends of the pin, once it's cut to length, and then shoulder or chamfer the end.
What this does is give the pin some time to upset a bit before the top starts mushrooming way out. I use my smallest ball peen hammer (pretty small) and just patiently tap it around and around, switching sides a few times.
Andy's method above probably does the same thing, but I don't find it necessary to bring the end of the pin all the way to a point...just a different style.
I set the pins before I'm done cleaning up the wood with the 120 belt, so a quick touch on a sharp belt cleans them right up without a lot of heat.
 
idiot ?:

If you don't put the pins in, until after the handle is shaped, how do you keep the holes lined up? Do you just stick some temp rods in there, during the glue up process? Do you glue 1 handle on at a time? or both?
 
seionage said:
If you don't put the pins in, until after the handle is shaped, how do you keep the holes lined up? Do you just stick some temp rods in there, during the glue up process? Do you glue 1 handle on at a time? or both?
Click to expand...

Yep. Epoxy off-side slab to tang. Use the tang bores as a template for undersize drilling. Glue up mark-side slab and back drill it with same bit. Then drill to nominal with sharp bit while everything is still large, square and parallel. Chippy material can be hit with CA glue to minimize blowout risk if you're fighting for thickness.

Yeah it can slow the workflow if you let it. Yeah other people will tell you how to do it their way. Ignore them, they are wrong.
 
So I can stick the pins in first while I am epoxying the handle then come peen it after? I always ended up with a sticky mess trying to peen while the epoxy was wet.


I do prefer to use the pins to hold the handles in the right place. I do most of the handle shaping before I epoxy the handles on though.
 
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