Tap and Dies

[Daniel]

I am completing a group buy for Tap and Dies in the group Buy forums. I have gotten a few messages that are concerned with the amount of confusion on these tools. Why are they so expensive? why are they even needed etc.
I am posting this here because I opened the group buy thread for comments by those that do use these types of tools and what they use them for. There is an effort in the I.A.P. to encourage Advanced Penmaking. there is a lot of attention being given to this buy. So all you Advanced Artist hop on over and give others a reason to jump in. Or at least more information to decide if this is a direction they would like to go with there hobby.
Thanks for the help.

 

[BRobbins629]

I was one of the original purchasers of the triple start taps and dies and I will try to answer some of these questions from my perspective.

First of all, multi start threads are common to capped pens although not 100%. From the outside, no one can tell the difference. It is only when you unscrew the cap that you notice a difference. One turn or so for a multi start thread versus several turns for a single start thread. All design options are available whichever way you go; its just that the multistart is more traditional for a pen. If you are unsure about venturing in multistart sets, get a set the same size with a single start fine thread and see how you like it. If it works for you, move up to multistart. Maybe by then, Daniel will get us a better price from China!

The reason why they are more expensive has mostly to do with production volume. Multistart sets are custom and single start are mostly off the shelf. Same reason why a handmade pen by one of our own sells for many times a production style.

When I decided to get my set, I had a few particular pen designs in mind where none of the kits would work. At $500 a set, I wouldn't have made the move but when we got a group together for about $200, I said why not. I am not a high volume pen maker, but I have made about 15-20 pens with the set. I have sold some in the same price range as I would for a medium to high end kit and by that standard, have already recouped my money.

If I had to come up with the best reason for doing this, it is to enable me to create pens with a personal signature. I think I'm on my way to that path. Some here can do this with creative blanks, but how many can say a stranger could pick your pen out of a group made with the same kit by others.

 

[Texatdurango]

Actually the path that brought me to using the multi-start tap and die set started with clips!

I was enjoying making closed end pens but when I started closing in the caps I ran into problems mainly how to attach the clip!

One thing led to another and it started making more sense to just make the whole pen without using the typical brass tubes and metal kit parts.

Of course, then the biggest problem was threading the two pen halves together and as Bruce mentioned, using a regular single cut thread, you had to crank the pen several turns to get it open and shut again.

That is where the multi-start came in. Now threading the cap to the pen was no longer an issue and I was free as a bird to design any shape pen I wanted.

 

[Daniel]

I'll offer my own tip concerning this. Take a little look through the advanced penturning forum and see what is going on along these lines. To me there is something really appealing about an acrylic pen that is not interrupted by metal center bands or cap ends. It is at this point that there is a distinction for me between pen Turning and pen Making also.

 

[skiprat]

I've played around with multistart threads too. But I'm no expert. I don't like to contradict my friends that have already posted but the amount of turns it takes to screw on a single thread as appossed (sp?) to multi start is not the issue, nor is tradition. To me anyway.
Here is my logic as to why we use multistart threads.
Take a good look at a standard bolt. It has a single thread. Threads on nuts and bolts work like wedges. The sharper the wedge, the more effective it works. The angle of this 'wedge' on a thread is called the helix angle. If you take a normal nut and bolt, you can actually hand tighten it so that you can't open it by hand. Try it.
Think of a wedge you stick under a door to keep it open. The sharper the wedge is, the harder it is to pull the wedge out. If the angle of the wedge was very steep then the wedge becomes less effective. Same with threads. But you can't alter the angle of a standard single thread.
Enter the multi start threads. We are looking for a 'happy medium' as far as the wedge effect is concerned. We have said that single threads are too effective. Two start threads are better than single. But a hypothetical 6 start thread would have a very steep helix angle and the cap would probably keep coming loose as it would not offer enough wedge effect.
Some, but not many, of our kits have 4 start threads. I don't really like them. The 3 start seems to work best for our needs and because of that, it is now tradition to use it.

That's my thoughts and they may only be worth what you paid - Nada:biggrin:

Using taps and dies to make pens can be a very trying learning curve. If you are not prepared to have many failures then don't do it.
However, I can assure you that there is nothing more rewarding than screwing on a cap where you made the threads. :biggrin:

 

[BRobbins629]

I've played around with multistart threads too. But I'm no expert. I don't like to contradict my friends that have already posted but the amount of turns it takes to screw on a single thread as appossed (sp?) to multi start is not the issue, nor is tradition. To me anyway.
Here is my logic as to why we use multistart threads.
Take a good look at a standard bolt. It has a single thread. Threads on nuts and bolts work like wedges. The sharper the wedge, the more effective it works. The angle of this 'wedge' on a thread is called the helix angle. If you take a normal nut and bolt, you can actually hand tighten it so that you can't open it by hand. Try it.
Think of a wedge you stick under a door to keep it open. The sharper the wedge is, the harder it is to pull the wedge out. If the angle of the wedge was very steep then the wedge becomes less effective. Same with threads. But you can't alter the angle of a standard single thread.
Enter the multi start threads. We are looking for a 'happy medium' as far as the wedge effect is concerned. We have said that single threads are too effective. Two start threads are better than single. But a hypothetical 6 start thread would have a very steep helix angle and the cap would probably keep coming loose as it would not offer enough wedge effect.
Some, but not many, of our kits have 4 start threads. I don't really like them. The 3 start seems to work best for our needs and because of that, it is now tradition to use it.

That's my thoughts and they may only be worth what you paid - Nada:biggrin:

Using taps and dies to make pens can be a very trying learning curve. If you are not prepared to have many failures then don't do it.
However, I can assure you that there is nothing more rewarding than screwing on a cap where you made the threads. :biggrin:

Friends? You have friends here? Not sure I agree with all your logic - some yes. I have made multistart threads that I can tighten by hand and not get apart without breaking the barrel. While tightness has to do with angle, it also has to do with the size of the hole drilled for the tap. With the 12MM tap, when I drill 7/16 hole before I tap, my threads are a little tight. If I use a 29/64 drill and the same male piece, the threads are loose. I still think multistart is more about keeping the same resistance to pull out and engaging the same number of threads with fewer turns. Now wedgies are something else.

Back at you friend.

 

[skiprat]

Hiya Bruce:biggrin:
LOL, as long as we agree on 'wedgies' can we stay friends? I'm running out of them:frown:
Now please try the following; reach behind you and grab your undies.
Now as hard and as quick as you can, pull them over the back of your head. That's a wedgie!!!:biggrin:

I think we are referring to two different things with regards to 'tightness'
I'm referring to the final 'lock' at the end of the threads. But I think you are talking about the 'fit' of the threads while still turning the cap on?

I believe most taps and dies are matched as 1st, 2nd or 3rd cut, esp for use on hard materials. I think the ones we generally use are just made to try and do all three cuts with one tool. Each pair also has a pre-specified amount of clearance.
If you are threading soft material like wood or plastic then if the cutters are matched with the correct clearance then the only reason for the tight threads would be that the drill was the wrong size for the tap and the material stretched while you were tapping and shrunk back when you removed the tap? I have no idea if a die can squash material that was too large in diameter.

I hope Daniel doesn't mind us hijacking his 'thread' :biggrin: Cos I enjoy reading this kind of stuff.

Now Bruce, be kind to me, I'm feeling sensitive today:biggrin:

 

[BRobbins629]

I not sure if I stretched the material or not, but all I know is how tight they are. I'm way over my head, but on the tight ones, if I go in and bore a little off the tops of the threads, they become looser.

And I'll always be kind to my friends.

 

[Daniel]

Keep going fellas I know I'm learning a thing or two. I've never thought of the wedge thing although it would seem to me to be true. I also seem to recall at one time that CSUSA made it a marketing point, although of the small print variety, that there caps on certain pens tightened with one twist. Now the wedge thing would be much harder to use as a marketing point I also see that a cap that attaches quickly easily and reliably is something my customers would appreciate. It is what I recall most being mentioned when these new cap threads came out.