What size hole to drill for certain size pins?

[LARRYZ10]

May I chime in on this subject? I always drill slightly oversize holes in my tang and even as Mr Apelt has said an even larger tang hole is fine. It's the fit of the pins in the scale that most of the better knife makers have different methods for. I noticed early on that not all drills are the same diameter and to make things worse the rod stock we buy varies in diameter also. So I always check the rod stock first for size with a dial or digital calipers and compare it to the drill size. You will find that you cannot press some pins into your scales holes by thumb pressure but once you run a Q-tip, with epoxy into the scale hole that the pin slides in like it is too small. Before you have a lot of experience you may want to drill a hole in a piec of scrap hardwood and apply some epoxy and try to push a pin in with thumb pressure. The ideal is too just be able to push in the pin with heavy thumb pressure. After you install several pins that work well you will know which drill to use and which rod stock to use. I buy my drills 10 pieces at a time and the Norseman super premium drills I use in 1/4 inch works perfect with the 1/4 inch rod stock I buy from Jantz knife supply. Not so with all other diameters but I can reduce the rodstock diameter by rolling it against a slack belt at 400 grit and by trial and error get a snug fit. Some of you may think that I'm making too big a deal about this but in my opinion a snug finished pin looks professional and is something that is so apparent when the knife is finished. Just my opinion. Larry

 

[TRfromMT]

I find that fitting the pin to the hole is the first step, and many good suggestions in all of the above posts. Try a few methods and you'll see what works.

Where things go wrong, and quickly ruin all your best efforts, is grinding them flush too quickly with a dull/used belt and getting the pins way too hot. This burns the wood and leaves a really unsightly black ring around the pin. If it's a mosaic pin, the epoxy can melt or chip, leaving voids around the smaller pins. Grinding pins flush takes careful consideration as much as the fit.

 

[12345678910]

I find that fitting the pin to the hole is the first step, and many good suggestions in all of the above posts. Try a few methods and you'll see what works.

Where things go wrong, and quickly ruin all your best efforts, is grinding them flush too quickly with a dull/used belt and getting the pins way too hot. This burns the wood and leaves a really unsightly black ring around the pin. If it's a mosaic pin, the epoxy can melt or chip, leaving voids around the smaller pins. Grinding pins flush takes careful consideration as much as the fit.

Yes.

This is really obvious, not just on "beginner" knives.

If you're using synthetics, try the synthetic pins.

 

[J. Doyle]

Surely you don't think drilling and reaming a hole to the proper size and shape is overly complicated;

I've already answered this Fred.....you didn't read or listen to my response. AGAIN....no, I don't find the process complicated. I find recommending this method to a new maker just trying to rehandle some blades unnecessary and over complicated for him in this case.

it's the correct manner in which a round hole is made.

In some cases. According to YOU ONLY, as far as I can tell, in this case. Did you notice that EVERY OTHER maker that replied in this thread just uses slightly oversized bits? Certainly you're not suggesting all these quality makers are 'wrong' and you're the only one doing it 'right' ......are you?

When they are drilling the pin hole in a thousand dollar bowie, it's no doubt going to be done using an undersize drill bit, followed by the correct sized ream.

Not at all a hard and fast rule. Most top tier bowie makers I know DON'T ream pin holes for straight knives.

How do you drill the holes in those beautiful Bowies you make?

Not with reamers. I save my reamers for folders mostly. I don't actually pin too many straight knives. When I do, they're mostly full tang. And you're welcome to look at one at a show sometime and tell me if you think the pin holes were precision reamed or not. And certainly feel free to critique my fit and finish if you so desire......anytime.

 

[Fred.Rowe]

I'm that guy who carries a set of calipers at knife shows looking to buy material that works for what I'm building. I've purchased pin stock , by mail, that when delivered was not close to the correct size. It's why I buy it in person.
When I have someone apprenticing in my shop, I pass along the best techniques I know of. No one will learn edge packing at Bethel Ridge Forge
They might learn the small refridge along the north wall contains cold beer and that I like one after forging all day.

The techniques I use in my shop are not the only techniques that can be used. Use those techniques that give you the best results is my advise. Whether I am teaching someone to punch thru a target, or how to drill a round hole, I am going to teach them the best way I know, to accomplish the task.

Regards, Fred

 

[Fred.Rowe]

I've already answered this Fred.....you didn't read or listen to my response. AGAIN....no, I don't find the process complicated. I find recommending this method to a new maker just trying to rehandle some blades unnecessary and over complicated for him in this case.



In some cases. According to YOU ONLY, as far as I can tell, in this case. Did you notice that EVERY OTHER maker that replied in this thread just uses slightly oversized bits? Certainly you're not suggesting all these quality makers are 'wrong' and you're the only one doing it 'right' ......are you?



Not at all a hard and fast rule. Most top tier bowie makers I know DON'T ream pin holes for straight knives.



Not with reamers. I save my reamers for folders mostly. I don't actually pin too many straight knives. When I do, they're mostly full tang. And you're welcome to look at one at a show sometime and tell me if you think the pin holes were precision reamed or not. And certainly feel free to critique my fit and finish if you so desire......anytime.

 

[Fred.Rowe]

J.
Teach what you want to teach at your shop. That is your prerogative. I'm not interested in arguing with you about this technique or that technique. My interest is in passing along sound advise I have garnered from working in a shop for 40 years. I still have all my fingers, I must be doing something right.

Regards, Fred

 

[Stacy E. Apelt - Bladesmith]

OK, everybody step back and take a breath.

We all have our methods and we all recommended them to the OP. There is o need to get argumentative about someone elses methods.

The reason I and many others recommend a larger tang hole is that unless you are a precision machinist, or very lucky, it is unlikely all three pins will slide through two scales and the tang if the tang hole is only a few thousandths over the pin size. I think every one of us has had a third pin hit the tang and not want to go through with the epoxy already on the scales.

New makers, which is the group we are talking to here, will have even more issues with such things as cheaper drill presses and scales that are not perfectly aligned and plumb.

 

[AVigil]

I think every one of us has had a third pin hit the tang and not want to go through with the epoxy already on the scales.

Count me out on that, that has never occurred to me.

That is why it is important to get the correct information and follow a set proven procedure.

It just really is not that hard, you can make it harder then it really has to be and that is part of this discussion.

If a person can not get a 3 holes to line up perfectly with a precise fit, then they need to keep practicing.

All to often you can see a pin on a scale to high or to low due to a larger hole in the tang and the scales shift in glue up.

Lots of good information in this thread, lets not stifle the discussion

 

[wcbill]

OK, everybody step back and take a breath.

We all have our methods and we all recommended them to the OP. There is o need to get argumentative about someone elses methods.

The reason I and many others recommend a larger tang hole is that unless you are a precision machinist, or very lucky, it is unlikely all three pins will slide through two scales and the tang if the tang hole is only a few thousandths over the pin size. I think every one of us has had a third pin hit the tang and not want to go through with the epoxy already on the scales.

New makers, which is the group we are talking to here, will have even more issues with such things as cheaper drill presses and scales that are not perfectly aligned and plumb.

Well said Tracy get over it guys

 

[Stacy E. Apelt - Bladesmith]

I understand what you are saying Adam, but I find it hard to believe you never had an alignment issue in your early days as a knifemaker. I know I dd, and every maker I know personally has had it happen.

When I drill the holes in the scales I put a pin through each hole when it is drilled. That way it can't shift when drilling the next hole. I do this again after drilling the second hole. This makes all three holes through the scales in perfect alignment. Unless that tang was drilled at the same time it is possible/probable that there will be some difference in the holes aligning. The tang holes are drilled slightly oversize to make installation quicker, easier, and avoid any issues from them being minutely different. I always dry-fit the




Here is where the math works out.
Lets say you drill the scales perfectly, but the tang holes are spaced .002" off. That isn't much and it wouldn't matter in most cases. But if the second hole is .002' off center to center along the x axis rom the first, and the third is off .002" in the same direction, the first and third hole are .004" off. The total misalignment is the same as one sheet of paper.
This doesn't even take in consideration that they may be off on the y axis as well.

A 1/8" pin is .1250" (theoretically) a brand new #30 is .1286" (hopefully). This allows a max of .0036" inch space in the tang hole for the pin, which is .0018" to one side of center .... assuming the pin isn't a thousandth or two larger than spec. Double that for two spaces and the max error tolerance is .036". The earlier calculated .004" total misalignment of the tang could cause the last pin to bind.

When you consider that many new makers will think .01" accuracy is pretty tight, this can really be a problem. Few hobby makers even have the ability to accurately in thousandths.
Drilling the tang holes at 5/32" or 3/16"" (25% to 50% oversize) allows for plenty of realignment without making the glue-up sloppy. The epoxy fills the void around the pin creating a shock absorber that may actually increase shear resistance.

 

[AVigil]

I understand what you are saying Adam, but I find it hard to believe you never had an alignment issue in your early days as a knifemaker. I know I dd, and every maker I know personally has had it happen.

If you secure one scale to the tang, I use ca glue, then drill through the tang and scale, adhere the opposite scale to the tang and drill through the hole in the first scale going through the tang and making a hole in the opposite scale, How on earth do you ever have a problem with the holes lining up?

I knock off both scales, do what I need to do and when it comes to install they line up perfectly EVERY SINGLE TIME.

If every knife maker followed a similar procedure they would never have a problem with holes lining up.

Maybe it is because I did not learn to line up holes while a knifemaker and learn this decades ago as a youth.

Honestly I find it difficult to believe everyone can not line up 3 holes

 

[Mecha]

What I do is drill the hole slightly bigger than the pin. Then one end of the pin is placed on an anvil, and I beat the other end of the pin with a hammer, upsetting the pin which swells and fills in the spaces. After it's ground smooth, it looks totally seamless! Might want to be careful if it's on delicate handle scales, I do this with metal pommels.

 

[Grapevine]

Thanks for all the advice everyone. I find the methods you all discuss fascinating. I'm not at all a maker nor will I be trying to be one. Some of the more precise methods are indeed above my level and my ambition at this point, but I am very appreciative that they've been mentioned and I will make a mental note of them just in case for the future, and I'm sure that any true would-be future maker who is lurking in this thread would find those methods and the discussions thereof to be useful as well.

I'm a collector/hobbyist whose interests in collecting knives have changed to wanting to use some of my more user grade customs as well as slightly higher grade factory knives. In using and enjoying the use of some of my purchases, I've found things that I would prefer to be different from the way they were originally made. So I'm going to modify things on these now user knives. Simple, cost effective, and room for user error is the ticket for me in this endeavor. I'm going to combine several things mentioned by different makers in this thread into my plan of action in order to try to be more precise up front but still leaving room for a novice like myself to screw up. And as suggested by many in this thread I will test out the method I chose on scrap pieces before proceeding to the real thing.

 

[Mecha]

Thanks for all the advice everyone. I find the methods you all discuss fascinating. I'm not at all a maker nor will I be trying to be one. Some of the more precise methods are indeed above my level and my ambition at this point, but I am very appreciative that they've been mentioned and I will make a mental note of them just in case for the future, and I'm sure that any true would-be future maker who is lurking in this thread would find those methods and the discussions thereof to be useful as well.

I'm a collector/hobbyist whose interests in collecting knives have changed to wanting to use some of my more user grade customs as well as slightly higher grade factory knives. In using and enjoying the use of some of my purchases, I've found things that I would prefer to be different from the way they were originally made. So I'm going to modify things on these now user knives. Simple, cost effective, and room for user error is the ticket for me in this endeavor. I'm going to combine several things mentioned by different makers in this thread into my plan of action in order to try to be more precise up front but still leaving room for a novice like myself to screw up. And as suggested by many in this thread I will test out the method I chose on scrap pieces before proceeding to the real thing.

Damn right. Ultimately the best thing is to drill a hole and put a pin through it and see what happens!

 

[Fred.Rowe]

Drilling oversize holes in a full tang knife especially those with more than one pin, is done for the same reason a carpenter measures twice, cuts once. There is no need to make things more challenging than necessary.
It's all good, Fred

 

[12345678910]

Get yourself a little index card of drill sizes....letter drills, number drills , fractional , metric all on the same chart is helpful to get exactly what you need.

Yes, if you're in the USA Starrett will mail them out to you free.
Wall charts and pocket cards.

If you're elsewhere, there are folks getting the freebies and selling them on ebay.

They are all over the net too as PDF's like I linked to but the printed cards and wall charts are so much prettier.

 

[12345678910]

.........

 

[Stacy E. Apelt - Bladesmith]

If you secure one scale to the tang, I use ca glue, then drill through the tang and scale, adhere the opposite scale to the tang and drill through the hole in the first scale going through the tang and making a hole in the opposite scale, How on earth do you ever have a problem with the holes lining up?

I knock off both scales, do what I need to do and when it comes to install they line up perfectly EVERY SINGLE TIME.

If every knife maker followed a similar procedure they would never have a problem with holes lining up.

Maybe it is because I did not learn to line up holes while a knifemaker and learn this decades ago as a youth.

Honestly I find it difficult to believe everyone can not line up 3 holes

Realx, no one is attacking you.
I understand your method, and it works fine for completely flat and parallel scales. It won't work as perfectly if the scales are rounded ( ivories and stag), or irregular ( jigged, sculpted, stag, or not perfectly cut slabs (new maker with not so good saws or sanding techniques.

I'm going to let it go now, as I have no wish to get in a "who does it best" debate. I was merely stating my method as a recommendation for a new maker.

 

[AVigil]

Realx, no one is attacking you

I think you are projecting some here, I do not feel attacked so that was a weird thing for you to say.

And what I posted is the best most accurate way for a new maker to make sure the holes line up, that is why it has never been an issue for me.

For those who have problems getting the holes lined up, give it a try. It will eliminate that problem so many makers seem to have.

BTW- if any maker needs help in getting the holes line up with round, stag ,taperd tang or jigged materials I can tell you how to do that as well and always have the holes line up, just let me know.