Odd Ball Tap

[ak diesel driver]

so I'm looking for a 1 1/8"-7 left hand acme tap. I've searched pretty good thought maybe you guys knew of some obscure sources

 

[schiker]

That does look like a bastard. Such that stocking price might be high enough to warrant a quote from some one like this....

http://www.natool.com/sites/default/files/public/acmetapsflyer.pdf

 

[ak diesel driver]

Sounds spendy. I did get the male portion out of the nut finally.a all I really need is to chase the nut. Fair amount of rust hmm I wonder if one of those rust remover liquids would work?

 

[btfarm]

Rotate one of the 3/4 copper pipe fitting wire brushes through the nut a few times with low speed on a varispeed drill running left hand

 

[Will L.]

Irwin is the world leader in taps. I dont remember their tech support number, the regular customer service number is 1 800 go Irwin.

I dont recall ever seeing an acme thread tap, but imagine they have to be out there somewhere. I can not imagine this being under $150.

Also if you have some of the acme thread you could use a thinwheel and cut the reliefs into it to make a chaser.

 

[ak diesel driver]

wouldn't 3/4 be too small? also the nut is 6" long the male thread is only about 1 1/2"long

 

[btfarm]

Then try a 1" brush. Tough to find one that long but if you can get at it from both ends.

 

[schiker]

Yeah, I believe that tap is going to be expensive unless you find a used one on ebay or something. Its a known thread not full out custom so maybe a non stocked item that they already have prints and manufacturing plans. The lead time might be more painful than the price (in comparison to other big expensive odd ball taps but still going to be expensive). If you were to get lucky and talk to the right person maybe you could find one of their customers that orders them and see if they are willing to part with a used one for little less money.

I like the brush idea and could just get messy with a can of penetrant or cleaning oil to clean out some rust and corrosion. Then maybe use a rust fixer. I'd be leary of starting with a rust eater or repairer in case it causes rust to swell up or change in anyway.

Don't know but might could plug one end or both with a dowel of sorts or if you could put a rubber over outside and or tape it up fill it with penetrant and let it sit. I had a tractor with top link of 3 point hitch stick with rust and once apart I just kept flushing with penetrant and working screw back and forth pull apart blow out refill and brush male thread with oil and repeat. Now I take off that link and leave inside oiled/greased up unless I am using it.

 

[ak diesel driver]

I picked up a 1 1/2" wire wheel today. Probably have to trim it down to make it work. If I can clean this up I will have scored an expensive vice for my milling machine.

 

[ak diesel driver]

I also bought a 1 1/8-7 NC tap just to see how close it is.

 

[Will L.]

Pics or a video? We want to share in the pain. Ok, i lied. I just like picture time.

I have not worked much with acme thread. Only once had a problem with it, and used my friends Victor jr and Miller to solve it.

 

[ak diesel driver]

So I soaked the nut in my solvent tank for a day or so. Trimmed down a wire wheel and brushed the nut pretty good. Looked pretty clean but was still really tight. Got it soaking in some rust remover now. The picture of the base is after I wire brushed it. That's how bad it all looked

 

[Will L.]

Since you can assemble and disassmble, can you rub some type of lapping compund (or pumice hand cleaner) on there and operate it back and forth with a cordless drill? Dont want to use an impact- the chattering can make it worse. Looks like that is what has been on that shaft many times before.

Looks like a vice? The nut is in the center of pic #2 with the set screw or is that a locking collar?

 

[ak diesel driver]

Parts cleaned up pretty good. Got the 1 1/8-7 NC LH tap today ended up being almost perfect. You can see in the picture of the tap how much material it removed. Next I'll order a rebuild kit.

 

[ak diesel driver]

Finally got my rebuild kit