Steel Guitar Builder

I do not know if you builders can answer my question or not, but what is the diameter of the rods that pull the fingers in the changer system?, I am getting ready to make the pull rods and just wanted to know what size they are, I am using a three raise two lower all pull changer.
Thanks, Steve B.

Hi Steve,
I use 2.4mm stainless welding rods, hope this helps.

Ron Mc

3/32, 7/64 and 1/8 are all used....depends somewhat on your bell crank attachments, changer finger hole sizes and desired thread. All this info is available in depth on the Steel Guitar Forum.

The 2.4mm that Maxi19 uses is essentially 3/32

I'm using 3/32 with a 3-48 thread

They generally use 3 sizes in the US measurement, (ss welding rod works great , 1/8", 7/64" , and 3/32" at the welding supply) ..Stormy. ps; on 1/8" rod I like to use a #5-40 tpi die, it's tite but always use some light oil for cutting and back out every full turn or so to clean the old cuttings out. For .109" u can use a #4-40tpi. Stormy. If u have trouble finding these dies try a gunsmithing supply, as they are common in that trade..

Let's bring this to the top for a while. You folks mention using 7/64 welding rod. Where the heck do you find it. I've tried my local welding supply stores and all the carry is 3/32 and 1/8. They don't carry 7/64 in any type of material much less stainless. Thanks for you help and information.
Lavern

ljs wrote:Let's bring this to the top for a while. You folks mention using 7/64 welding rod. Where the heck do you find it. I've tried my local welding supply stores and all the carry is 3/32 and 1/8. They don't carry 7/64 in any type of material much less stainless. Thanks for you help and information.
Lavern

Ask for stainless "TIG" rods Info off the label on the box. Also available in 1/8"X 36", and 3/16"X 36" for pedal pull rods.
Harris Welco
3/32"X 36"
part # 0308T50

http://www.airgas.com/p/HAR0316T60...(for 1/8")

Yes, 3/32, 1/8,......but I can't find 7/64 in stainless. I have some of the 3/32 & 1/8 but it is not the correct diameter for a 4-40 thread. I did find 7/64 W-1 tool steel which is not stainless and that is from McMaster-Carr ......but I suppose it would work. It would have different rates of expansion and contraction if one was trying to change copedents and was going to add pull rods to an existing setup. Thanks for your information.
LaVern

LaVern, If you haven't already, read this...Hope this helps...Bill

http://steelguitarforum.com/Forum5/HTML/006319.html

Yes I have read that old posting, but I still don't see where you can buy 7/64 stainless steel rod. No local, or internet listing that I see. Several folks have mentioned welding shops but the last time i went to the welding shop I use, they said they do not make a stainless steel welding rod in 7/64. They make it 1/64 smaller @3/32, and 1/64 larger @ 1/8". The only reason I even considered looking for 7/64" is I have had problems with my home threaded 4-40 threads on 3/32 rod either stripping out because I was unable to get the correct size hole for self tapping or the opposite and the nut being too tight to comfortably adjust them.

My thinking is 7/64" is .109 and the correct major pitch diameter for a 4-40 is .112 so with only a .003 difference 7/64 would work with much less problems.

I may be incorrect on this but I am pretty sure Gene Fields solved this problem by using 3/32 stainless rods and having a Rolled thread put on them which actually displaces the material to produce a larger diameter. I have decided that if I ever need to build pull rods again I will use either 7/64 W-1 or even .112, either is available.

I will still be open to someone telling me where to get 7/64 stainless or at least the drill size that is being used for a good holding 4-40 thread on 3/32 rod. I don't have a full set of number drills so I in the past bought individual sizes trying to get the correct size and was not happy with the results. Thanks for all the effort and I apologize if I'm missing something.

LaVern

Here is some info on drill and tap sizes and the decimal equivalents for some letter and number drill bits:

http://littlemachineshop.com/Reference/tapdrill.php

If you spend a little time poking around that web site, I think that you will find a lot of similar useful information.

I don't know where you will find the 7/64" welding rod. The last couple of times that I have gone to buy welding rod, the selection seemed to me to be significantly reduced. I just assumed that they are not making as many sizes as they used to, probably because of the new welding technologies. I will try and remember to ask next time I'm there.

HTH. and Good Luck with your project!