870express 116 #1 Posted July 14, 2019 I'm an amateur, ok? I'll admit that. And I know I should have paid attention in high school shop class. But now I find myself in need of some knowledge about cutting threads on an exhaust pipe for my RJ58/59. Finding 1/2 inch threaded pipe is no problem, just pick it up at Lowe's. But Lowe's doesn't stock said pipe in the 3-1/2 inch length required for my tractor. So I got a longer length of their pipe that was already threaded on both ends, and cut off one end 3-1/2 inches long. I took that piece to a local plumber and asked him to put threads on the cut end. He laughed and said he couldn't do it because his die (cutter) was 2-1/2 inches deep, and there was no way he could clamp such a short pipe. I didn't argue with him, but figured he just didn't even want to try. So does anyone out there have any suggestions? I need a 3-1/2 inch piece of threaded pipe, and I am at least willing to try. Share this post Link to post Share on other sites
870express 116 #2 Posted July 14, 2019 Never mind. I found it. I guess I just needed to vent. https://www.supplyhouse.com/Bluefin-BLN050-350-1-2-x-3-1-2-Black-Nipple Carry on. 1 Share this post Link to post Share on other sites
oliver2-44 9,929 #3 Posted July 14, 2019 The plumber is right in that his dies have a hard time working with that short piece of pipe. If you have a machinist friend, or a local farm fit it shop, they can cut them on a lathe. 1 Share this post Link to post Share on other sites
adsm08 2,231 #4 Posted July 14, 2019 When I went through needing custom pipe lengths I went to Harbor Freight and got a manual threading kit and clamped the pipe in a vice. The HF kit didn't cut wonderful threads, they were a little chewy, but it did work. 1 2 Share this post Link to post Share on other sites
Racinbob 11,301 #5 Posted July 14, 2019 Are you sure they don't have it in the bins with all the pipe nipples? If not try Menards, HD or Ace. 4 Share this post Link to post Share on other sites
wallfish 17,112 #6 Posted July 14, 2019 It's been a long while since doing mine but I used off the shelf pieces of pipe and never had to have any threads cut on the pipe. 2 Share this post Link to post Share on other sites
adsm08 2,231 #7 Posted July 14, 2019 35 minutes ago, Racinbob said: Are you sure they don't have it in the bins with all the pipe nipples? If not try Menards, HD or Ace. At least around me Home Despot seems to have the best pipe selection, especially in larger sizes. I needed Ford Special Tool "Locally Fabricated Sleeve" the other week for something I was doing and HD was the only place around that had a pipe in the diameter I needed. Everyone else stopped about 1/2 inch too small. 1 Share this post Link to post Share on other sites
AMC RULES 37,141 #8 Posted July 14, 2019 What are you using the 3.5" length for? Share this post Link to post Share on other sites
870express 116 #9 Posted July 14, 2019 (edited) 1 hour ago, AMC RULES said: What are you using the 3.5" length for? My RJ59 has a Clinton B1290 engine and the first section of pipe coming out of the exhaust port requires exactly 3-1/2 inches to clear the frame. This photo shows the setup using a 3-inch section of pipe, which is too short, and the elbow is not tight. Edited July 14, 2019 by 870express Share this post Link to post Share on other sites
adsm08 2,231 #10 Posted July 14, 2019 1 hour ago, 870express said: My RJ59 has a Clinton B1290 engine and the first section of pipe coming out of the exhaust port requires exactly 3-1/2 inches to clear the frame. This photo shows the setup using a 3-inch section of pipe, which is too short, and the elbow is not tight. If you are not copying an old piece make sure you add 1/4-1/2 inch to your measurements for area taken up by thread. 1 Share this post Link to post Share on other sites
71_Bronco 1,072 #11 Posted July 14, 2019 You can get a 3-1/2" piece, threaded on both ends, from McMaster for $1.62 + shipping. Can also get a 4" (not sure if you've tried 4" or not) I have an account with them for when I need some odd special bolts or whatever. 1 Share this post Link to post Share on other sites
870express 116 #12 Posted July 14, 2019 1 hour ago, 71_Bronco said: You can get a 3-1/2" piece, threaded on both ends, from McMaster for $1.62 + shipping. Can also get a 4" (not sure if you've tried 4" or not) I have an account with them for when I need some odd special bolts or whatever. Thanks, but I already ordered one from this place - https://www.supplyhouse.com/Bluefin-BLN050-350-1-2-x-3-1-2-Black-Nipple - last night. $0.84 + shipping. 1 Share this post Link to post Share on other sites
ACman 7,624 #13 Posted July 14, 2019 Seems any good hardware should carry a 1/2”x3 1/2” nipple or have nipple cutting attachment. Sure wish I knew how many feet of pipe I’ve ran in my lifetime as a HVAC installer . In a pinch I would thread a coupler onto a short piece of pipe then clamp it in the vise . Next screw your piece you need to thread into the coupler . Now thread your nipple . Yes they tighten up as your threading but it can get you out of a pinch. 3 Share this post Link to post Share on other sites