tap and die help

[glycerine]

I'm a little confused, mostly because I have never used a tap and die. But like Ron and others, I would like to try my hand at kitless work when I finally get the shop set up.
So here's my confusion. After reading some info on threading, it seems that you should not use a MATCHING tap and die? For instance, if I use an M11 x 1 die, I should NOT use an M11 x 1 tap, but rather a M10 or possibly M10.5? If that's the case, how do you know exactly what you need to use? Do you just have to test it out first and see what fits best?
Thanks...

 

[Texatdurango]

I'm a little confused, mostly because I have never used a tap and die. But like Ron and others, I would like to try my hand at kitless work when I finally get the shop set up.
So here's my confusion. After reading some info on threading, it seems that you should not use a MATCHING tap and die? For instance, if I use an M11 x 1 die, I should NOT use an M11 x 1 tap, but rather a M10 or possibly M10.5? If that's the case, how do you know exactly what you need to use? Do you just have to test it out first and see what fits best?
Thanks...

Wow, I've never heard anything like that, but it's certainly not correct.

Let's say you want to make a pen where the cap screws onto the lower body and decided that 11mm diameter is just right for your design and you like the look of the 1mm pitch threads.

You would turn a tenon on the lower body to the appropriate diameter than grab your 11mm x 1mm die and cut the threads. Then drill the appropriate hole in the cap then take your 11mm x 1mm tap and cut the inner threads.

When finished you will have matching threads so the two halves can screw together.

Now that's said, there are some ways to "tweak the fit"!

Let's say you look up the proper drill size for your tap in some old machinist handbook and it says to use drill size xxx. This may not give you the fit you want using plastic pen parts so using a slightly larger drill bit then using the 11mm x 1mm tap will give you a nicer fit, a bit of play, but better overall.

One thing I do occasionally is to take a razor blade and lightly trim the inside threads so the body threads in smoother. It doesn't take much, just remove a little fuzz at a time.

 

[cnirenberg]

Jeremy,
The confusion may be in the fact that there a few things going on at once. Like George said, the cap and body screw together, the threads must match. But there is also the threading for a blind cap, if you want one and the nib section as well. These threads are smaller and can be a different pitch, but again the tap/die sizes must match for these pieces too.

 

[glycerine]

Ok, thanks guys. Maybe I misread or those people purposefully wanted a looser fit, but wanted to make sure before I go and buy any tap and die sets...

 

[fernhills]

Ok, thanks guys. Maybe I misread or those people purposefully wanted a looser fit, but wanted to make sure before I go and buy any tap and die sets...

I must have misread it to, b/c that is what i thought to. After reading all of the info here, i am about to start one soon, just for fun. Carl

 

[skiprat]

I hope it wasn't me or one of my 'thread threads' that mislead anyone, but if it was please say so :wink:
I made reference to 'slightly' changing the hole size or outside diameters to make things easier, but I don't think I said to use non-matching taps and dies. At least I hope not:biggrin:

 

[Glenn McCullough]

I just used the tap and dye on a pen body for the first time, George made some suggestions and I read Skippys tute and didnt get that at all from either. Anyway, I used the matching taps and dyes I got from Lou and and a group buy, here. Though the end result was not what I was looking for (so no photo), the fit of the threads were just right! so go back to the matching tap and die idea, please.
Thanks, Guys.

 

[workinforwood]

Yep, if you tapped an 11x1 and then die'd a 10.5x1, that would be a pretty darn loose fit. What you can do though, is you can take your 11x1 die and give it a squeeze to make it just a hair smaller. This will make the thread diameter slightly less, so it would be like maybe turning your 11x1 die into a 10.9x1 die and that would be ok because then you get just that tiny bit of slop making the threads go in easier. That is if you have split die's or adjustable dies.

 

[glycerine]

Ok, sorry about that "misunderstanding". Carl, I'm glad I wasn't the only confused one.
Thanks for the info guys, I'm straight now. I actually only own one tap and would like to get more (and dies), so I didn't want to get the wrong "stuff"!

What would you say the most common sizes are for "kitless" pen making...?

 

[cnirenberg]

What would you say the most common sizes are for "kitless" pen making...?

Jeremy,
What I did a while back was to get the HF Tap and Die set that included the M10x1.0 tap and die. This was only because, I was using the El grande nib (which is fairly close to a M10x1). Both the rollerball and the FP nibs work-and if they are bit off, run the die over the threads. The set also had a 1/2x20 and I used that for the cap and body. HF is about a mile away from my house so it was not a big deal to go and pick them up.

 

[RAdams]

The size difference that is the root of the confusion was a reference to different drill bit sizes.

If you are tapping a 11mm hole, you can use different drill bits to get different fits. a 10MM drill bit will give you a bit more meat on the threads than a 10.5 and so on.

At least that's what i got from it...

 

[btboone]

Part of the issue is that the plastic threads on nibs are molded. Plastic has shrinkage when it cools from molding temperature, so that affects the pitch length slightly. They are usually not the perfect 60 degree threads of machined metal parts, but more like 70 degrees, and have rounded tops and flat bottoms.

 

[Texatdurango]

Jeremy,
What I did a while back was to get the HF Tap and Die set that included the M10x1.0 tap and die. This was only because, I was using the El grande nib (which is fairly close to a M10x1). Both the rollerball and the FP nibs work-and if they are bit off, run the die over the threads. The set also had a 1/2x20 and I used that for the cap and body. HF is about a mile away from my house so it was not a big deal to go and pick them up.

Jeremy, I finally got started on my "How to make a pen from scratch" tutorial today and in it I chose three taps that work just fine with each other for the size pen I am doing in the lesson and here they are:

1/2-20 SAE - main threads on upper and lower body
10mm x 1mm - lower body inside threads for the standard Berea section
9mm x 1.25mm - Threads for the finial to screw onto the cap.

I chose the 1/2-20 since it is readily available almost anywhere and looks nice on this size pen and the metric sizes because they are available in the cheaper Harbor Freight sets.

I chose the 10mm x 1mm because it most closely fits the Berea sections which are readily available from suppliers.

I chose the 9mm x 1.25mm because once threaded, the finial fits really snug over the ring of the clips I use and that's one of the keys to holding the clip on nice and snug.

I mention this to let people know that they can indeed make a very nice pen without spending hundreds of dollars on expensive tap and die sets.

I should have it done in a few days and I'll post the results in this forum.

 

[cnirenberg]

George,
I got a 1/2x36 T/D afterwords and found that the threads were nice and fine, but really didn't work out for all different materials. Alumilite threaded the best, but some acrylics just didn't cut cleanly. I'm back with the 1/2x20, and a few threads will do it, not the whole tenons worth... But this is what you told me at the very beginning, "you will find out what works for you and what dosen't...." Good advice.

 

[workinforwood]

The size difference that is the root of the confusion was a reference to different drill bit sizes.

If you are tapping a 11mm hole, you can use different drill bits to get different fits. a 10MM drill bit will give you a bit more meat on the threads than a 10.5 and so on.

At least that's what i got from it...

Uh..not quite Ron. If the tap is 11x1, then you drill a 10 mm hole. You do not drill a 10.5 or a 9.5 hole. If you drill a hole that is any size larger than a 10 mm hole, then the flat surface between the points will have to do some cutting. This is makes for too much surfaces being cut at the same time, which is expanding the walls of the blank and will likely end up with a cracked pen. If you drill a 9.5 hole, the threads might grab but they will be super sloppy. You could get away with a 9.9 mm bit, but the best thing to do is stick with a 10 mm bit for an 11x1 tap. An 11x.75 tap would require a 10.25 drill bit. etc.... A die is the same way..an 11 mm die requires an 11 mm rod or tennon. Any larger will be crushing on the plastic. A very smidgion less than 11mm will be ok, like say 10.95 mm, but if you were to spin your tennon down all the way to 10.5 for an 11 mm die..then you will be super duper loose fit again.

 

[RAdams]

Uh..not quite Ron. If the tap is 11x1, then you drill a 10 mm hole. You do not drill a 10.5 or a 9.5 hole. If you drill a hole that is any size larger than a 10 mm hole, then the flat surface between the points will have to do some cutting. This is makes for too much surfaces being cut at the same time, which is expanding the walls of the blank and will likely end up with a cracked pen. If you drill a 9.5 hole, the threads might grab but they will be super sloppy. You could get away with a 9.9 mm bit, but the best thing to do is stick with a 10 mm bit for an 11x1 tap. An 11x.75 tap would require a 10.25 drill bit. etc.... A die is the same way..an 11 mm die requires an 11 mm rod or tennon. Any larger will be crushing on the plastic. A very smidgion less than 11mm will be ok, like say 10.95 mm, but if you were to spin your tennon down all the way to 10.5 for an 11 mm die..then you will be super duper loose fit again.

Yes Sir, I was talking about the general principal. i think??

 

[Rfturner]

My father has a ton of taps and dyes i will have to put them to use, he rarely uses them. He has been a mechanic for 27+years so he has collected tools for a while