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PostPosted: Thu Jun 10, 2010 11:30 pm 
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Cocobolo
Cocobolo

Joined: Tue Jun 03, 2008 1:12 pm
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Location: Plainfield, IL (chicago)
I have been making my own single action vintage style truss rods. 3/16" rod threaded to 10-32. I buy the truss rod adjustment nut, but make my own anchor on the oposite end. Basically I drill a hole in a 3/8" rod and tap it for 10-32. Screw the rod in and peen over the threads so it can not spin out. Problem is - besides breaking taps in the rod, it takes a long time to make them.

Looking for barrel nuts of steel threaded 10-32 center tapped it possible. I can't seem to find them online. McMaster carr doesn't seem to have what I am looking for.

I also found these.. http://www.drillspot.com/products/38637 ... ld_nut?s=1 but I am not sure if there is enough thread (and peening) to keep the rod from pulling out of the nut when tightening the adjustment nut.

Any help would be great.

PS: I will be making about another 50-75 necks this year, so I need to find something not only easy to use, but economical. Stew Macs versions are $2 each. I would like to find the for about $0.50 or less each if possible.

Thanks.

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PostPosted: Fri Jun 11, 2010 5:51 am 
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Koa
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I know what you mean. I still get them from stewmac. I've seen these made where the anchor end is just bent down 90 (maybe 3/4" ) & anchored into the heel. Whatever prevents the rod from rotating.

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PostPosted: Fri Jun 11, 2010 6:24 am 
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Cocobolo
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Joined: Wed Dec 17, 2008 9:04 pm
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Location: Bossier City Louisiana
First name: René
City: Bossier City
State: Louisiana
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Found these 10-24 cross dowels. Can you change to 10-24 on the anchor end? Also, I don't know what the differences are in strength and adjustability between fine and standard threads.
Maybe somebody can chime in.

http://www.woodpeck.com/crossdowels.html

René


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PostPosted: Fri Jun 11, 2010 6:51 am 
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Cocobolo
Cocobolo

Joined: Thu Feb 09, 2006 2:06 pm
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Location: United States
JRE Productions wrote:
I have been making my own single action vintage style truss rods. 3/16" rod threaded to 10-32. I buy the truss rod adjustment nut, but make my own anchor on the oposite end. Basically I drill a hole in a 3/8" rod and tap it for 10-32. Screw the rod in and peen over the threads so it can not spin out. Problem is - besides breaking taps in the rod, it takes a long time to make them.

Looking for barrel nuts of steel threaded 10-32 center tapped it possible. I can't seem to find them online. McMaster carr doesn't seem to have what I am looking for.

I also found these.. http://www.drillspot.com/products/38637 ... ld_nut?s=1 but I am not sure if there is enough thread (and peening) to keep the rod from pulling out of the nut when tightening the adjustment nut.

Any help would be great.

PS: I will be making about another 50-75 necks this year, so I need to find something not only easy to use, but economical. Stew Macs versions are $2 each. I would like to find the for about $0.50 or less each if possible.

Thanks.


If you keep breaking 10-32 taps in mild steel, you're doing something wrong. Make sure you keep the tap lubricated ( motor oil will do fine), and, when the tap starts to get tight ( or, about every 1/2 turn) back it out a little before turning clockwise again. Never force it. And, you are using mild (unhardeneded) steel rod, right? - like the stuff they sell at hardware stores.

You could also switch to 3/8 aluminum rod - 6060-T6. You can always fine 6061 3/8 rod cheap on Ebay. It will tap much easier and faster than steel, be a bit lighter, and still be way stronger than the threaded rod. ( and, cost maybe 10 cents a piece instead of 2 cents each)

There's no reason to switch to a 10-24 thread - it would be harder to tap, the tap would be weaker and more likely to break, the adjustment would be coarser and more difficult, and the rod would have less strength ( easier to break in the guitar)

Phil


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PostPosted: Fri Jun 11, 2010 8:28 am 
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Brazilian Rosewood
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The cheapest solution, and probably the most reliable is to bend a 90 degree angle at the end of the rod and insert it into a hole drilled in the heel. Its what I do.


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PostPosted: Fri Jun 11, 2010 9:23 am 
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Cocobolo
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Joined: Tue Jun 03, 2008 1:12 pm
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Location: Plainfield, IL (chicago)
Thanks Guys.

I guess I should qualify my statements:

1) Fender Style Bolt on necks, so not a lot of room for the anchor.

2) Yes, mild steel from HD or Menards. 3/8" rod drilled with correct bit. I buy a 36" piece and drill holes every 5/8" along the entire shank. Then place that into my vice. Add oil on the tap and begin tapping the hole. When I get almost all the way thru...the tap starts tightening up and binding. This is using the 1/2 turn forward...1/2 turn back method. Eventually it would seem the tap gets weak, after about 4-5 holes, the tap ends up snapping. Funny thing is, sometimes I can do an entire rod no issues and sometimes, I can't make more than a few holes.

3) When I drill the rod, I use motor oil for a lubricant. It gets very hot after drilling a large number of holes. I keep adding oil to the bit/hole while drilling. Am I hardening the rod? Later, some holes tap very easy, other tap very hard.

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PostPosted: Fri Jun 11, 2010 10:08 am 
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Cocobolo
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First name: Bert
Last Name: Foster
City: Gainesville
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Zip/Postal Code: 30506
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Joe,
After the hole is drilled do you chamfer the hole before you start trying to tap?
Try slowing down when tapping. The tap may be heating up and expanding and causing it to bind. I'm an old gear-head an I have experience tapping hundreds of holes over 40 years of restoring, hot roding and building engines. I would also invest in a can of Tap Magic. It really makes a huge difference. Any automotive store or hardware should have Tap Magic.

Before I started buying truss rods I made my own and being a gear-head I've always had a welder and I would weld a tab on the fixed end. You could make a bunch of truss rods ahead of time without threading the rod or tapping that end of the rod. Go ahead and drill the hole so that the rod just slips through and take it to any body shop and they will have a MIG welder ask them to spot the fixed end of the rods and I'd bet they might not even charge you. If you were near me I'd do it for you.

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PostPosted: Fri Jun 11, 2010 11:11 am 
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Cocobolo
Cocobolo

Joined: Tue Jun 03, 2008 1:12 pm
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Location: Plainfield, IL (chicago)
Thanks Foster. I am an old gear head too. I owned quite a few Model T's and muscle cars before getting into 30's street rods. Its been a while since I built my last rod (35 for 5 window coupe). Love it just the same.


I am wondering if I am hardending the holes when I douse them in oil to keep them cool. Some holes work fine, others get tight and bind right away. I also wonder if the oposite if true... if the steel is so soft that the threads don't hold thier shape and that causes them to distort or break off lodging into the treads of the tap. (I have had similar issues with threading the rod too).

J

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PostPosted: Fri Jun 11, 2010 11:48 am 
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Brazilian Rosewood
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If the end block is mild steel...maybe think about thread forming taps. When hand tapping, start the threads with a cutting tap....just to get it started straight. Then pull out the cutting tap and switch to the "thread forming tap" or "roll foming tap". That'll give you much stronger threads than cut threads because the threads are formed by mushing the material into shape, which essentially forges the thread. Mind you, the holes for thread forming taps are a little larger than for cutting taps. I can get you the formula for hole sizing if you want. PM me if you want it. I don't have it handy where I'm writing.

If you create a blind, bottom tapped hole, clean everything up real well with acetone, use JB weld prior to mating the rod and block, and then use enough torque, it's hard for me to imagine that will EVER come loose. That's a theory, of course. You could certainly test that idea thoroughly before you committed it to a guitar neck.

Spot welding the assembly is more guaranteed though it brings in a few issues that must be controlled. If you heat up metal too much you may anneal the material, which in this case means to soften it, and weaken it. MIG welding is better than torch welding for this reason for this application but if you use a small propane torch to get the assembly very warm prior to MIG welding, you'll get a better, smoother weld.

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PostPosted: Fri Jun 11, 2010 12:36 pm 
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Cocobolo
Cocobolo

Joined: Tue Jun 03, 2008 1:12 pm
Posts: 466
Location: Plainfield, IL (chicago)
I don't know much about the taps. I am using what I think is the standard 4 flute tap (about $5). I am seeing spiral flute taps that look great too but have not bought one yet. At one point I was using a cordless drill for taping, but have since gone back to hand. Either way the tap begins to bind and breaks on me.

Thread forming taps seems interesting to me... I'll have a look.

Bottom line has to be cost and time effective. I can make my own truss rods (anchor and rod) for about $1.00-1.25 The TR nut cost me $2.00 so I have about $3.00 in a excellent truss rod. The cheapest I can find them pre made with the right TR nut is about $8.00. That extra $5 over the 100+ necks a year I will build ends up a huge amount. While making them is time consuming, its not $500 worth of time for sure.

J

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PostPosted: Fri Jun 11, 2010 1:07 pm 
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Cocobolo
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Location: Plainfield, IL (chicago)
Zlurg.

I went ahead and found a deal and ordered a thread forming tap to try. I will have to figure out the drill size to make it work.

I also may have an option to have a friend of a friend weld the nuts on for me, so that may work out too. I need to make another 20 pretty quick.

Thanks,
Joe

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PostPosted: Fri Jun 11, 2010 3:20 pm 
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Brazilian Rosewood
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In the movie Slingblade, Karl checks the gas in the motor to see if that's the problem.....sure enough, there's no gas :)

I should have also said to be very sure that you are drilling the right hole size. Sometimes, if you start the tap at a perfect angle you can get away with a hole size that is technically too small. But if the tap starts at all crooked, it can bind and snap off.

http://academic.evergreen.edu/projects/ ... js-tap.htm

The formula to use for your new thread forming tap is called, "cold form tapping" on this web site. Plug in the numbers and get the drill size. In steel using 60-65% thread is more than enough grip. Thing is: be very careful to use a size that is at or slightly larger than the size called out.....which is to say that if the drill called out is .170" don't use a drill that is even .001" smaller....go bigger instead.....but not more than .002". The larger the hole gets away from the called out drill, the less percentage of thread will be achieved. This is especially true for thread forming but is also true for thread cutting.

Run the numbers for the general formula at 75% to make sure that you weren't using a drill that was too small when you were cutting the threads.

I'd recommend that every time you buy a tap, you also buy the corresponding drill called out by these formulas. It's likely that holes size is causing your problems if you are not carefully selecting your drill sizes.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic


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PostPosted: Sun Jun 13, 2010 1:08 am 
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Cocobolo
Cocobolo

Joined: Tue Jun 03, 2008 1:12 pm
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Location: Plainfield, IL (chicago)
I have been buying the taps from Ace that come with the cooresponding drill. So I think its the right size...but it is definitely getting tight at the botton of the hole. I have tapped many holes for auto repairs, hot rod builds etc. So in general..I know what I am doing. But this one is perplexing. I think 3 things are adding to my problem. 1) The hole at the top (where the drill bit starts) seems to a bit larger making the top have easy to tap, but the as the drill aligns and drills about halfway or more, it must straigten out and get tighter. 2) Because I am drilling hole after hole after hole, (only 5/8" a part), the rod gets very hot. I am using oil to cool it, which is probably hardening it pretty good. The first few holes always seem to tap better than the last few. Also, I think it some steel tools better than others. I have problems when sending a dye down the cooresponding rod. Sometimes the threads start to mash, and other times, the threads start to move off center to the rod. Usually about 1/2"-3/4" inch in from the end. I would have thought the dye would chase the rod pretty straight all the way down. So I am pretty sure part of the problem is the steel itself.

I bought a few other taps too. 1 is a spiral tap that I think can be used in a drill or motor as the chips clear via the spiral. I actually end up about 3 rods short today due to the anchors I had to scrap. So if I have time I might try to make a few more tomorrow.

Ultimately, once I have a bit of spare time, I may make up the parts to a huge batch of rods and have Steve Wheeler's friend weld them up for me. The problem is, its about the same amount of work...but requires I drive to get the work done. At least the taping the anchors at home can be done in my boxer shorts in the middle of the night.


J

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PostPosted: Mon Jun 14, 2010 12:52 pm 
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Walnut
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In all that you said I don't find any reference to using three taps... When I shop for a tap for manual use here in Spain, I _always_ get three taps in a small box, which are slightly different. They look like this:

http://complubot.educa.madrid.org/tecno ... do_003.jpg

Notice that they are marked with rings. The order in which they must be used is: single ring, double ring, no rings. I don't think I could use the final tool without having used the other two before it. And pardon me if I didn't understand that you're using this already...


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PostPosted: Mon Jun 14, 2010 1:25 pm 
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Brazilian Rosewood
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JRE Productions wrote:
I have been buying the taps from Ace that come with the cooresponding drill.

J


Don't use hardware store taps. MSC carries good ones (Cleveland, Greenfield). If one is a lot cheaper than the others, it's not because they like to give something for nothing. Get a couple of good ones; breakage happens.

Don't use hardware store pipe threading oil. Get good tapping lube or use automatic transmission fluid (the red stuff).

You can use your drill press turned by hand to get good alignment of the tap. Or buy a tapping jig, since using the drill press is a pain and makes you want to have a third hand.

Chamfer the hole before tapping. Do it on the exit side, too. that's where you're binding.

What kind of vise are you holding the rod in? How are you starting your drill on the round surface?

Sounds like you are drilling too fast. When your drill speed and feed pressure are right, you get a long spiral shaving. If you are getting chips, it's not right. While you're at it, get a good quality drill bit from MSC. Get a few of them. You can't drill a rough hole and expect it to tap well.

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PostPosted: Mon Jun 14, 2010 1:48 pm 
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Also, StewMac is only about a buck-fifty if you get a bunch of these. Compare that to the cost of tools and the time.

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PostPosted: Tue Jun 15, 2010 11:59 pm 
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Joe,
If you drill the holes large enough to fit over the rod you could Tig them. Take about 5 seconds per weld. Just a few fuse welds would work fine. You know anyone who Tig welds it wouldn't take anytime at all.
Link

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PostPosted: Wed Jun 16, 2010 1:50 am 
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Brazilian Rosewood
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Quote:
Thanks Guys.

I guess I should qualify my statements:

1) Fender Style Bolt on necks, so not a lot of room for the anchor.


You may drill the hole for the anchor to show up in the neck heel. Many Fender necks exhibit this. Or simply route the back of the neck, bend the rod, and just shorten the "skunk stripe" by a little bit for the truss rod to anchor in. You may use epoxy to make sure that end stays.

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PostPosted: Wed Jun 16, 2010 1:27 pm 
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Cocobolo
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Location: Plainfield, IL (chicago)
The adjustment is at the heel and the anchor under the first fret. The neck is about .500" thick (under the fingerboard) and the Anchor is about .375-ish in size. It has to be wide enough not to spin but yet not deep enought to get exposed in carving.

Image

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PostPosted: Wed Jun 16, 2010 2:18 pm 
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Brazilian Rosewood
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My bad... I was thinking of those rear routed truss rods that adjusts at the headstock rather than the heel.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com


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PostPosted: Wed Jun 16, 2010 2:49 pm 
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Koa
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Lots of good info and suggestions here for sure!

Joe, you mentioned buying the rod from Menard's or HD. Some of the steel rod I've bought at stores is plain crap when it comes to any kind of machining. Either dead soft or harder'n the hubsohell with a few ball bearings thrown into the scrap iron melt for good measure.

http://www.onlinemetals.com/merchant.cfm?pid=4476&step=4&showunits=inches&id=7&top_cat=1

Might suggest buying some rod like this and it should tap like a dream. Or you could use leaded mild steel rod like this:
http://www.onlinemetals.com/merchant.cfm?pid=7580&step=4&showunits=inches&id=285&top_cat=197

Nelson


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