The Home Machinist!

Back when I worked in a machine shop, one inviolable rule was "absolutely NO threaded rod in place of proper studs." Nobody seemed to know why, but the supervisors were adamant about it.

It was such a big deal I reflexively avoid it in my home shop, but... is there any real reason NOT to use all-thread if you need an odd-length stud?

Use anything you need to use as long as it's strong enough.

Pete

Depends on the application, I'd think.
Threaded stock may not yield the desired pitch diameter, and it may not have the needed tensile strength. It most likely would not be an acceptable substitute for a proper stud, which may rely on the pitch diameter for proper seating and holding, as well as not having a grip (assuming one would be desirable). Interference threads are made accordingly, whereby the pitch diameter is where there's interference.

Mixed emotions on my behalf. I'm not a fan of the stuff, but I've used it on many occasions, and keep a small supply on hand for situations that can be solved by its use. Really handy for temporarily holding things in place.

H

Depends a lot on the threaded rod too. Hardware store all-thread is the bottom of the barrel in terms of dimension, yield strength, & concentricity. Grade 8, Class 10.9 & 12.9 are available from most industrial suppliers some with ANSI or MIL certs to guarantee it's material properties and dimensional consistency. I have some remnant lengths of 1/2" and 5/8" grade 8 of known, quality origin and I've used pieces of them in place of studs with no problem.

I would tend to say the stuff you avoid using is probably the hardware store variety and probably worth avoiding for anything you don't want moving around. Nuts tend to shift side to side and threads fold over under torque

I assume you mean in milling setups.

1) You could overtorque the all thread and have a catastrophic failure while milling.

2) With repeated use allthread could eventually fail due to accumulated wear.

I use it a lot.

John Hasler wrote: ↑Thu Sep 13, 2018 8:08 am
I use it a lot.

Me too; I mostly use 12mm threaded rod, I cut down some nuts to fit in my drill press table slots. like Harold says, a box of handy sizes.
I think it works great; it stretches evenly along its length instead of only stretching at the threads like a stud.

You don't want the hardware store threaded rod. What you want is B7 threaded rod. This is actually better than the studs in most clamping sets. Most common size for the home shop is 1/2"-13.

https://www.ebay.com/itm/1-2-13-x-8-B7- ... -wdSvJ7EfA

The next most common size I would think would be 3/8-16.

https://www.ebay.com/itm/3-8-16-x-8-B7- ... Swcj1aDwU6

They also make a heavy 1/2-13 nut that takes a 7/8" wrench that doesn't have a flange on it that is made of the same stuff. I have used other sizes of nuts before that were made of the same material. When a stud in the set wears out then I replace it with B7. Lasts longer!

For those of you who live in or around Portland, Oregon you can buy this at Parkrose hardware on Sandy BLVD.

Richard W.

One other thing I forgot to say is at Parkrose hardware they have bulk heat treated washers as well. While not as thick as the ones you might buy at MSC they are durable enough that I don't buy the expensive ones from tool stores.

Having used a few miles of RediRod for pulling bearings and coupling, I wouldn't be shy about using it for a milling set up. If you are going to use 1/2 " rod and tighten that much, I''ld be more worried about pulling the wings off the T-slots. We always assumed RediRod was grade three. BTW look up the tensile difference between grade three and grade eight. Locally good RediRod is gold coloured and about as rare as real gold.

Completely agreed on avoiding hardware store threaded rod, though I have used it without catastrophe on light clamping tasks (more like stabilization).

I also have a decent supply of B7 threaded rod, which I use much the same as a stud when necessary, though it's used more often as described above for cobbling up bearing removers/installers and the like.

I made up a bunch of clamping studs using high strength threaded rods from Fastenal. Unfortunately Fastenal now only sells business to business. I could have bought the material from McMaster but didn't want to pay shipping and wait 2 days.

I can't imagine tightening anything to the mill table so tightly as to threaten even the worst threaded rod.

Conrad_R_Hoffman wrote: ↑Thu Dec 06, 2018 7:32 pm I can't imagine tightening anything to the mill table so tightly as to threaten even the worst threaded rod.

I have seen table slots broken from over tightening. Including table slots that take a 7/8" stud.

The big reason for me on the of B7 is they last so much longer than the ones you get in the clamping sets. The quality of the stud material has really deteriorated a lot in the last 47 years that I been working in the trade. So all my replacement studs are B7.

Richard W.