On an engine lathe, picking up an internal thread to re-cut it, can be frustrating. This video shows a rock solid technique for getting the job done. Take a Look !!
Joe, putting the DTI on the end of the boring bar was bloody brilliant. I can see some other uses for this idea! Well done Also, when you visit the Fang Farrier (dentist) don't be shy about putting in a request for his or her broken tools. They only throw them out, and they can be very useful to us "engineers" 😎
Hi Joe - your use of the split thread for clarity purposes is a great teaching aid . Keep the great videos a coming ! thannks for taking the time to do this
Thank you for showing Joe. The say, that when you stop learning you are done, well, following you and your videos I can categorically say I will never stop learning, THANK YOU FROM MD AND HAVE A GOOD DAY.
When I was an apprentice, I was shown this technique, but used the compound slide to find the centre of the groove. The indicator was looking at the compound movement. It is also the same technique for an outside thread to be picked up. The only difference was that after the lathe engagement and had checked the thread pitch , the chuck was hand turned in the direction of the thread cut. This made sure there was no backlash in the gear train. Also lock the carriage so it is stable in position. Great post Joe as always.
IT is over 50 years that I have operating many type of engine lathes ,Turret lathes and CNC lathe . I never new how to pick up an inside thread. Thanks a lot i really appreciate this video. Thanks Thanks again and again.
I have in the past done it strictly visual by adjusting as the tool rubs in one point. Using the dial indicator to split the difference is a good idea.
Joe, I wish I saw this video yesterday as I was cutting a 1-7/8 x 6 spindle adapter. One of the threads got buggered up near my undercut and I had a seriously hard time picking the thread back up to finish the job. Now I know for next time! Thank you as always for what you do for us novices.
I learned how to do threading from your vids. Made my first thread yesterday but I forgot to put it in reverse and made a pristine left handed thread hahaha live and learn. You r a genius man. Thank you
Last time I chased a thread was using standard Aloris holders and an insert bar. I used the compound to feel either side of the thread and noted the travel and backlash. Bounced back and forth until I found the root and backed off a few thou. Make sure you have all the backlash loaded in the correct direction on everything! Especially the half nut. Joe I like the use of the indicator. I was running more seat of the pants to chase a very large UNS optical thread.
Thanks for sharing this idea, thankfully I have not had to pick up internal threads yet but have picked up on a number of external ones. I really like your idea for threading with the spindle in reverse and am now looking for a reverse threading bar to the one I have. Thank you for sharing your tips and tricks, it is very much appreciated as you have some cool ways pf doing things!
You don't need a reverse handed threading tool, in fact it won't work, even with the lathe running backwards. In the same way that a LH nut will not run onto a RH thread, even if you turn it around. Just turn the conventional RH threading tool you have upside down, or leave it right way up but at the far side of the hole, like Joe does.
Fantastic! That is one job that has always caused me the most grief... Thanks! The boring\threading bar jig is outstanding...one holder and all bar sizes on center.... amazing.
Another good video Joe!.... One caveat might be, for novice machinist, is to not forget that the job came in as a repair, meaning that the threads will be mashed, rolled over, gouged, etc, so their start number of .020" in this video case, needs to be sneaked up on to avoid chipping a tool on the damaged spots. Well done !
Your instructional videos have made me a much better machinist. I am so thankful for your material and your friendly presentations. I live in a remote location in Greenland and access to your videos gives me access to the best teaching anywhere, yours! Thank you, thank you.
Awesome technique, as always, Joe! Thanks for posting. The concept of threading away from the chuck is just brilliant. So simple, why hasn’t it been done like this forever?
It's funny when you see this for the first time you go -"duh! Now I don't have to be a ninja with the half nut!" I started to use it all the time because my lathe has a metric leadscrew and no threading dial. Makes the whole stop-out-reverse-in-forward thing sooooo much easier for when you can't unlock the half nut during threading.
Hey Joe, thank you so much for your efforts and planing to present relevant and purposeful video content to our machinist community. BTW, please start a senior division for your maze challenge for the 2020 Summer Bash, no prizes needed, just bragging rites for us old machinists.
Joe, where the hell were you 40 years ago when I started Machining?? If I ever get to Austin someday, I want to shake your Hand. you are awesome. Keep it coming.
Great Technique as well as video Joe Thanks heaps for this along with all your other tutorials. This is not something I have encountered as yet however I am aware now of a sound and accurate process to do this. Many thanks Joe from John, Australia.
Nice procedure Joe, I wrote to you last winter about a similar situation, I was into during restoration on a very old screw jack that had broken on my Grandfather when a wood wheel came off the axle on a fully loaded hay wagon being pulled horse team on the way back to the barn it was sometime in the mid-s20. My father always told the story about Papa pulling the broken jack out from under the wagon mad as hell and walk over to huge gully and toss it as far as he could. The jack was rediscovered in the early s70s when the farm was being developed into an apartment complex by an excavator operator that was good friends with my father. I guess since it was buried deeply in a clay swamp it was preserved fairly well. That's when I first heard the story about the jack, my dad was about ten years old at the time it happened. My dad hung onto that broken old jack for the rest of his life and it was passed on to me with the request to get it working again. I did, but it's only an ornamental piece now. I could have done a much better job had I saw your video first. My sister has it hanging on a wall in her family room now along with many other artifacts from our family. Thanks!
that was brilliant joe. thanks for showing how to pick up an internal thread. you are an arsenal of very usefull machining information and totally love your channel. thumbs up bigtime.
The Arachnid on your whiteboard looks more like an Formicidae... Anyway, this is another of your videos that I liked very much. Your way of explaining of what and why you are doing things is something that makes me follow your channel. Being an amateur machinist with an engineering background, I learn something new by watching your videos. Regards from the Nethrlands.
Good stuff Joe. The half part was great for the visual. I've had to do this a few times... more so with od threading. I once had to pick up a 10-32 thread on the cnc to thread mill it a little larger when it shrunk with heat treating. Basically used the same principle as you have described here.
Joe, this has been a godsend for me. Threading in reverse is a revelation making it so easy to work to a dead stop or should I say from a dead stop. Brilliant! I just did an internal thread only 1.5 mm deep and 0.5mm pitch!
@@bpark10001 In truth it was a custom thread of 7mm dia but 50 tpi. This meant I could engage the half but using the timing dial on my imperial Myford.
Engine Lathes are easy. I was doing this 30 years ago. I just came up with a new process two days ago on a CNC lathe without a compound. 3 5/8-12 ID thread repair on a 10' long telescoping tube. I picked a position behind the Chuck to make a timing mark on the Head Stock and Mounting Ring. I used a small amount of JB Weld to cover a small spot of about the first 4 thread. After setting Z0 at the end of the tube I checked the timing marks then moved the threading bar to the center of the first full thread. Marked down Z-.175" I set program to start at Z+.100". Run first pass and stopped. Checked the marks over the JB Weld. Looked Good. Run the Program to end. Needed minor adjustment to X diameter and about 0.004" to Z. Ran 10 tubes before quitting time.
@@joepie221 I just re-watched this video because the new to me lathe also has a collet draw tube that has been dropped. Looking forward to when the VFD gets in so I can try this out myself.
Awesome Video JOE Just got in 3 different sizes IL threading tools and inserts. Always had used company threading tools and inserts. Seen it done several different ways . This is the only was I have seen that works 100% for me. Thanks for sharing these younger guys I know will be in the shop first thing trying this. Awesome video as usual Watching in Alabama
Very cool and exacting method of picking up the threads after a screw up when threading. I’m a total novice but just recently was trying to make a spindle nut protector for L-00 spindle on my old Clausing 5900 lathe in which I’m adding a lever collet closer . Anyway I screwed up midway cutting the external 3.5” x6tpi thread. I spent about 30 minutes thinking about how I save the mostly finished nut I was making and did a lot of what was described in this video. I love the the indicator because I just eyeballed my repositioning of the boring bar. This was very cool. Thanks again. I really like your videos Joe. They almost always hit home as very useful.
Hi Joe Excellent video again, I used to work in a Ballscrew factory in Coventry 🇬🇧,1980 to 2005 and nobody cut threads weather it was a ball track or threads the way you do, I now do it your way, thinking about it your way would have helped a lot!
the hardest thing sometimes is to get the part to run true in the chuck. then deal with the baclash in the machine. thanx joe i do like the bar setup with the indicator!!
Nice video techniques, you are no amateur. Also like the way you used a sectioned piece of work to illustrate the cut. I've known of turning from, how would you say, on the back side with the spindle turning backwards, nothing like threading a blind hole, done it many times, making camera lens adapters, etc. I've always done the threading by "feeling" where the bit was, not by using the dial indicator and splitting the difference to find the center of the thread. Nice work, as usual. Jim
@@joepie221 I watch all your videos. I'm always waiting for the next. So much knowledge and experience, you always do your videos in a very organized format that makes it easy to apply in the shop. Thank you once again.
I hope I never have to use that trick. At the very beginning of this demonstration My only thought was, how's he gonna line this up. very clear demonstration Thanks Joe