Question about tapping tube for JJ's

[baldilocks]

Can I expect a good outcome if I attempt to tap 1"-14 and 1.25"-12 threads in to appropriately sized dom tubing to accept johnny joints? My concern lies in being able to do threads this large by hand. A local shop wants $125 to tap one end of 4 tubes. I could save money by doing it my self if its feasible.

 

[richardlillard1]

Don’t try to reinvent the wheel, just go buy some 2” .250” wall and these.

Affordable Threaded Tube Inserts: 1 1/4, 7/8, 3/4, 5/8, 1/2, 1 1/2 | Barnes 4WD

 

[reddingcruiser]

X2. Hard to beat threaded inserts for accuracy if you don't have the machine tools to do the job.

 

[baldilocks]

What I have is a set of Metal Tech rear control arms on my 80. One end is a JJ the other is a sloppy poly bushing set up. MT used tubing sized to tap for JJ’s. So, I was looking to cut off the poly bushings and tap the tube like MT did to run JJ’s at both ends of the links I already have instead of spending $350ish to build a full set from scratch.

How difficult would it be to cut threads of that size inside the tube without special machinery?

 

[baldilocks]

Don’t try to reinvent the wheel, just go buy some 2” .250” wall and these.

Affordable Threaded Tube Inserts: 1 1/4, 7/8, 3/4, 5/8, 1/2, 1 1/2 | Barnes 4WD

Yeah, I was looking at tube inserts and these came up. Barnes doesn't seem to have the 1”-14 size that is needed for the smaller upper link JJ that Currie makes specifically for the FJ80 bracket width of 2.375”.

 

[Mace]

That big of a tap by hand suuuuccckkkkssssss...

Find someone with a lathe and have them do it IMHO.

 

[baldilocks]

That big of a tap by hand suuuuccckkkkssssss...

Find someone with a lathe and have them do it IMHO.

Yeah I did but he want $125. That’s what prompted me to post this question.

Thanks for the feed back.

 

[richardlillard1]

Yeah, I was looking at tube inserts and these came up. Barnes doesn't seem to have the 1”-14 size that is needed for the smaller upper link JJ that Currie makes specifically for the FJ80 bracket width of 2.375”.

I’m sure google can point you in the right direction. I would have posted my findings, but I saw ballistic fab come up in the results and just closed the tab out of disgust.

 

[nukegoat]

Just weld them in

 

[nukegoat]

Dont you work some job where you have access to machine shops and stuff? just do that

 

[baldilocks]

Dont you work some job where you have access to machine shops and stuff? just do that

No easy access to a machine shop. Probably not a good idea to weld on the heat treated JJ bolt and cup. Currie doesn’t make a weld on JJ to fit fj80 brackets.

I have two choices: cut off the links I now have and get them tapped or build a whole new set using threaded inserts.

I’m leaning toward building a new set.

 

[nukegoat]

No easy access to a machine shop. Probably not a good idea to weld on the heat treated JJ bolt and cup. Currie doesn’t make a weld on JJ to fit fj80 brackets.

I have two choices: cut off the links I now have and get them tapped or build a whole new set using threaded inserts.

I’m leaning toward building a new set.

I doubt the johnny joint cups are special but you can cut, sleeve, weld, etc. Not airplane science buddy.

Also cartridge joints suck

 

[baldilocks]

I doubt the johnny joint cups are special but you can cut, sleeve, weld, etc. Not airplane science buddy.

Also cartridge joints suck

My three years of experience wth JJ’s and the many years of info posted to the World Wide Web speaks a different story, at least for JJ’s.

 

[cruisermatt]

You could cut the existing tubes farther back and sleeve the outside for a size that would let you use a weld-in threaded insert.

I would just pay the $125 and have them tapped though.

 

[SuperBuickGuy]

they think it's going to take 1 1/4 hours per end to tap? the only way that operation could take that is if they are cutting the threads with a thread cutter not a tap.* While the tap is not cheap ($133-$174 at Grainger), they may be willing to use your quality tap and run it in their lathe. If you ask them, do not bring them a Harbor Freight tap - yeah, I know they're cheap but how cheap will it be when you have to bring them another, more expensive tap after they blew up the first one on their lathe?

*the operation is: clean pipe, cut, reset, cut, reset, cut. Add to that time one tool sharpen per pipe... I still think it's a high estimate, but there it is. You'll have to judge this for yourself, it may also be the shop saying "no" without saying "no" because their opinion on how you should do this is different then yours.... in that case, there's a bunch of shops around, find one that doesn't have a cold breeze blowing up their skirt. In honesty, the shop I've settled on would simply buy the tap so that I keep coming back and charge 15 or so minutes a hole.

 

[GLTHFJ60]

I wouldn't try to tap that by hand. Tapping 1/2" is a pain by hand without a large enough tap handle. You going to do one end right hand and the other left hand thread so you can adjust length easy? Taps that large aren't cheap. From Fastenal, looks like you'll be in it ~$260 for USA made taps for left and right hand for 1"-14, then another ~$350 for the 1.25"-12 taps.

 

[baldilocks]

The taps I saw on the internet were not that expensive so they must have been junky products. I will pay the shop if I don’t start from scratch and build a new set using weld in, threaded tube adapters.

 

[Mace]

Look at the pricing. If you get your weld in tube adapters you are looking at approximately $15.00 ea (rough estimate). You need 4 so $60 right there. Then you will need the tubing.

Ruff stuff has the 1.75x.250 wall dom tubing. Assuming a 36" arm, you will need 72" of tubing which is $74.00..

I suspect it'll be close to a wash on pricing by the time you are done. And honestly, just getting the machine shop to mod your current arms is likely a heck of a lot faster and easier.

 

[baldilocks]

Look at the pricing. If you get your weld in tube adapters you are looking at approximately $15.00 ea (rough estimate). You need 4 so $60 right there. Then you will need the tubing.

Ruff stuff has the 1.75x.250 wall dom tubing. Assuming a 36" arm, you will need 72" of tubing which is $74.00..

I suspect it'll be close to a wash on pricing by the time you are done. And honestly, just getting the machine shop to mod your current arms is likely a heck of a lot faster and easier.

Yes, building a set of links myself from scratch using the 4 JJ’s I’m already running and ordering 4 more would be just about the same money as buying 4 JJ’s and paying the shop to tap the 1.75x.290 wall lower links I have now. Not sure on the dimensions of my smaller upper link tubes but they are tapped and accept a JJ with 1”-14 shank.

My 80 see’s some rock crawling and will probably see less now that I have moved to WA and no longer live two hours from Rubicon and the like, so now I’m considering going with an oem rubber bushing at the axle end of these links where the poly bushings are now. Maximum flex is not needed on a rig that roams the earth on roads more than bolder strewn trails.

 

[Mace]

Sounds like you have a couple decisions to make on how you want to go forward. Good luck