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View Full Version : Help to chase threads on a Jet 1442...



Mauricio Ulloa
09-03-2009, 4:30 AM
Hi,

I need to make treads with my current lathe. It is a Jet 1442. I've been reading and watching videos on thread chasing, but it seems that a lathe with a speed controler is needed. Specially because slow speeds are required. The lowest speed in my lathe is 450 rpm. It has about 6 predefined velocity settings, but it doesn't have a speed controller.

I've been investigating the posibility to change the motor for a DC one and to attach a speed controller to it, but this option costs about $700. The other option was to buy a thread chasing jig like the Klein or the Baxter. The available option is about $530. Then I thought about using a variable resistance in the power line of the lathe, but it seems that it would reduce the torque of the lathe and probably it would damage the motor.

Has anybody found a way to do some thread chasing in a similar lathe in an economic-reasonable way? :confused:

Thanks in advance for your help...!

Jeff Nicol
09-03-2009, 6:15 AM
I built my own threading jig that mounts to the ways of the lathe and uses the spindle to hold the cutter. There are numerous people on the web that show how they made there own also. What I did was buy a cross slide table for $80 and made a block that has a threaded rod with 16tpi with a 1x8"tpi on the end to hold a chuck or faceplate. Then you can move the box and lid in and out to get it into the correct position to get the spinning cutter to contact the box, as you turn the threaded rod the box moves into the cutter at the number of threads on the rod holding the chuck thus giving you the same amount of threads per inch as the rod. You will have to make a few passes to get it perfect, and that is where the cross slide table comes in. Once you make the first pass back it out and then increase the depth of cut, make sure that the threads are not cut to deep, the tops of the threads should be a littl flat not sharp. This will allow them to break easier.

So check out the web and you will find some very easy builds for threading jigs, once you have the basic concept, some trail and error tinkering and you should be able to get one made for a lot less than a motor and controller or one of the commercially available ones.

Jeff

Keith Spaniel
09-03-2009, 7:29 AM
I dont have a variable seed control,so i turned a wooden pulley that was bigger than my largest pulley on the spindle side. Made it snug and used my handle nut to hold it on. (RIKON) I got a larger belt also .It slowed down my lathe to around 200 rpm. Thats a good speed for threading ,ive been told .
It seems to take a lot of time to get good at chaseing threads by hand

Im going to try to make a threader and not invest in the hand tools.

Jeff ,could you post a photo of your threading jig? Or a link to some plans to build one? I have looked all over for plans to build a threader , but no luck.

keith

curtis rosche
09-03-2009, 12:51 PM
i have a 2.65hp DC motor that i could sell you, i think all it needs is a control knob

ed walker
09-03-2009, 5:30 PM
here is an article on another board.http://www.woodcentral.com/articles/turning/articles_833.shtml
Hope this helps.A year or so ago I made my own rose engine that works on the same principle.That site I believe was woodartbyjack.Google rose engine and you should have no problem finding it.

Keith Spaniel
09-03-2009, 6:22 PM
ED,
Thank you very much for those links.They are great.

:)keith

Mauricio Ulloa
09-04-2009, 1:21 PM
Thanks a lot for the link Ed! Jeff, I understood the concept. Could you please post a pic of your jig to clarify it even better?

Dick Mahany
09-04-2009, 3:52 PM
I have a simple setup consisting of a couple of nuts welded to a steel bar with a threaded rod and an adapter to hold my chuck. The assembly just mounts into a Bitmore vise and provides the neccessary degrees of freedom. The threaded rod and nuts can be chosen to suit the number of threads desired. It has worked fine for me and is a much less expensive alternative to the commercially available jigs. A muffler shop could weld the nuts for little cost. I did one for 14 TPI and another for 8 TPI.

Michael Short
09-04-2009, 5:05 PM
Dick, Can you post a bigger picture of your setup? That is really cool. Thx.

Dick Mahany
09-04-2009, 5:22 PM
Dick, Can you post a bigger picture of your setup? That is really cool. Thx.

Michael,

There is a photo of the set up at the attached link:
http://picasaweb.google.com/dmshopshots

Hope it helps.
Best of luck

Michael Short
09-05-2009, 10:01 PM
Dick, Thanks for the link to the your pics that helps a bunch. Have a great weekend.

Bill O'Conner
09-06-2009, 12:37 PM
you could chase threads at 500 rpm's just take a little more pratice. A demo I saw before I brought my thread chaser used a 1014 jet non VS to show how it was done.


Bill