What size fitting?

[The Sweet Spot]

I am getting ready to build my first tubing tool. I have the vise grips and a large pair of channel locks ready to go. What is the fitting size, that will be mounted to the vise grips, to grip the tubing? I am building this to use on as many different tubing sizes as possible. (5/16" to 3/4" or 1") Is it possible to make one tool for all these sizes? I just figured I would ask rather then experiment myself. Any help would be great.

[jmayerl]

For 5/16 tubing get a 1/2 coupler. It will only work for 5/16 and nothing else. Mainline tools (3/4, 1) don't use couplers, they use a different style of holder, more like a clamp.

[wiam]

Mine uses a 3/8 connector nut. Made for connecting threaded rod. Run a 5/16 drill through it to makes threads less sharp (prevents damage to tubing) Then run a 7/16(I think) bit in about 1/3 of the length. This allows the fitting to go inside to help align. You will need a separate tool for mainline(I do not use a mainline tool)

[The Sweet Spot]

Cool, thank you for the fast response. I have one vote for 1/2" and one for 3/8", both for 5/16"? I'm not saying either of you are wrong, I know there are many ways to do the same thing. That much of a difference could be made up by the blade that cut it. Did either of you make your own tool? I do understand reeming out the fitting end, so you could clamp on closer to the tubing edge. The idea is good about smoothing off the threads, so as not to scar the tubing. Thanks

[West Mountain Maple]

1/2"-13 threaded rod connector is what you want if you really want to try to make one, however if you are dealing with more than just a few taps, I highly recommend not wasting your time and tools and bite the bullet and get the parallel movement tool. I've made a couple pairs with channel-locks and vise grips, and they suck. If you do try to make a pair use good pliers, real Channel-locks, one pair i made with cheapos the pliers would jump the grooves.

[wiam]

Cool, thank you for the fast response. I have one vote for 1/2" and one for 3/8", both for 5/16"? I'm not saying either of you are wrong, I know there are many ways to do the same thing. That much of a difference could be made up by the blade that cut it. Did either of you make your own tool? I do understand reeming out the fitting end, so you could clamp on closer to the tubing edge. The idea is good about smoothing off the threads, so as not to scar the tubing. Thanks

I have a two handed tool that was made by a friend of mine about 20 years ago. I have a one handed tool that I made last year. Both have Visegrip brand on them. Both have 3/8 connector nuts on them. Both for 5/16 tubing. I do not use one handed tool much. I would not trade my homemade two handed one for a $300 deluxe model.

[The Sweet Spot]

Thank you all for the help. I will be trying the 3/8" connector and will ream it out like wiam said. It just sounds like a good way to do it.
Thanks Troy