Newb question: how difficult is this?

I Dont Care About You said:
I've seen a 3-wire set used and I want to say I owned a set at one time. A 3-wire measurement takes at least three hands and maybe more. Talk about an insane balancing game. :(
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Jesus! Really?

We must have been doing it wrong, then, because all the folks that I worked with had no problems using them. Once you wrap your head around the formulae used to calculate the measured distance over the wires, you can look up the specs for the thread Class you are making, and make a note of both the Maximum and Minimum sizes you need to hit as a direct reading of the Mic, rather than having to keep running your measured distances through the formula.

A gob of Plasticine or a rubber eraser were the usual go to's, but simply using the anvil to hold the two wires in place and feeding in the Mic on to the third, was pretty normal.

Am kinda curious where you got such experience, that they never bothered to show you how easy this stuff actually is?
 
trevj said:
Jesus! Really?

We must have been doing it wrong, then, because all the folks that I worked with had no problems using them. Once you wrap your head around the formulae used to calculate the measured distance over the wires, you can look up the specs for the thread Class you are making, and make a note of both the Maximum and Minimum sizes you need to hit as a direct reading of the Mic, rather than having to keep running your measured distances through the formula.

A gob of Plasticine or a rubber eraser were the usual go to's, but simply using the anvil to hold the two wires in place and feeding in the Mic on to the third, was pretty normal.

Am kinda curious where you got such experience, that they never bothered to show you how easy this stuff actually is?
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I think it's doing it as a hobby vs job. After you spend countless hours (20,000 hours is 10 years) behind a lathe they are as easy to use as a shovel or rake and you end up cutting threads almost daily and depending on the shop there could also be lots of repair work (Picking up threads or chasing them)

Wait until they have to cut some 6 start threads
 
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Evanguy said:
I think it's doing it as a hobby vs job. After you spend countless hours (20,000 hours is 10 years) behind a lathe they are as easy to use as a shovel or rake and you end up cutting threads almost daily and depending on the shop there could also be lots of repair work (Picking up threads or chasing them)

Wait until they have to cut some 6 start threads
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I haven't spent near that time behind a lathe, and I GUARANTEE that the apprentices I taught, had not, but they all grasped the concepts well enough to be expected to be cut loose to doing a passable job of it.

Never had to make a six start thread. I have some passing knowledge of a couple different ways to do it (eg: indexing the work, vs trig and backing out the compound and advancing the cross slide to account for the individual threads), but it wasn't something that came up.

It just never seemed as complicated as it is being made out to be!
 
Cover the barrel threads with sharpie/magic marker and see where the offending muzzle device rubs it off, there's quite a few different ways for threads not to fit.
 
I'm always amazed by how many otherwise proficient machinists chose to cut threads to fit a part, instead of to a spec.
If you aren't threading to a spec, that's not a 5/8-24, it's some oddball thread you came up with that just happens to fit one component. It might not fit anything else out there.
Do yourself a big favor and get yourself a Machinery's Handbook, and a set of wires.
Don't tell yourself that you're being "more precise". A thread doesn't locate on its major diameter anyway.
Hope I didn't hurt anyone's feelings.
 
Jonnyofalltrades said:
I'm always amazed by how many otherwise proficient machinists chose to cut threads to fit a part, instead of to a spec.
If you aren't threading to a spec, that's not a 5/8-24, it's some oddball thread you came up with that just happens to fit one component. It might not fit anything else out there.
Do yourself a big favor and get yourself a Machinery's Handbook, and a set of wires.
Don't tell yourself that you're being "more precise". A thread doesn't locate on its major diameter anyway.
Hope I didn't hurt anyone's feelings.
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The FIRST thing you have to know about Standards, is that there are so bloody many of them to choose from!

Wires are the long way around, when you are trying to find a way to make an inside thread work.

And, to be perfectly frank, I have bought a lot of stuff that looked and behaved, like it had been translated through at least five languages, over the phone, by guys that had never seen the real thing, before it was laid down on paper...As well as having been handed said paper... All well and good when everyone sings from the same song sheet. Not so much, when real world collides with theory!

Picking up a thread, inside or out, is not Black magic, nor is it akin to creating life from nothingness. When you understand what you are doing, and understand which way gets you what you want, as far as the movements and (oooh scary!) backlash, you can accomplish a bloody lot of good work, without a lot of stress in your life.
 
adamg said:
Buddy of mine has a gunsmith-fit barrel for his bolt action, meaning the gunsmith cut the action tenon and muzzle threads.

Turns out the 5/8x24 muzzle threads aren't cut quite deep enough, so one brand of muzzle brake goes on, but another won't.

I know 'only what I've seen on youtube' about lathes. But to me, this would be very difficult to go back, put the barrel on the lathe again, and cut the threads deeper, because the "timing" of the feed mechanism is hard set relative to the chuck. So you'd have to position the barrel in the chuck within like 1 thou for it to cut the same path again.

Is there some feature or technique I'm not aware of that makes this easy?

I guess the other question is, how easy is to to buy a 5/8x24 die thread cutter?
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I think there are Youtube videos for that, try Blondihacks or Tubalcain.

Grizz
 
I don't thread to suit anything. Thread to spec. A barrel is a hell of a lot more expensive then a brake, and what if you decide to change to a different brake. if the brake doesn't fit, then you know for sure it's the brake
 
Update to the original post:

My buddy ended up buying a 5/8x24 die and die holder from amazon for something like $50. He was able to run the die down the threaded muzzle, and removed a considerable bit of material. He said it was pretty easy, and afterwards the brake installed very nicely.
 
OP,
The muzzle threads should have been a Class 3A thread.

Chasing a die on the muzzle renders the thread a Class 2...at best.

Make damn sure that the bastardization once installed is aligned properly or a bullet strike will destroy more than the brake.

Good Luck!!
 
Jonnyofalltrades said:
I'm always amazed by how many otherwise proficient machinists chose to cut threads to fit a part, instead of to a spec.
If you aren't threading to a spec, that's not a 5/8-24, it's some oddball thread you came up with that just happens to fit one component. It might not fit anything else out there.
Do yourself a big favor and get yourself a Machinery's Handbook, and a set of wires.
Don't tell yourself that you're being "more precise". A thread doesn't locate on its major diameter anyway.
Hope I didn't hurt anyone's feelings.
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Before I retired early due to the fake virus, we frequently had to thread shafts for bearing jam nuts. If the nut was in the building, we threaded to a close fit with the nut.
Either on an engine lathe or a CNC lathe.
If it was not available to us at the time, we measured over wires. The nuts were always in tolerance so it didn't matter either way.
 
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