Rear spindle thread on import lathes

[carlsbad]

I'm making a rear headstock spider for my Jet. My spindle has M50x1.5mm threads on the rear end and has plenty of them exposed to thread the spider onto. Do Grizzley, Enco, and other import lathes use the same thread here?

Here is what my spindle looks like:

Here is the spider installed:

External view:


thanks,
jerry

 

[Ggmac]

What size jet is it ?

 

[hoz53]

I'm making a rear tailstock spider for my Jet. My spindle has M50x1.5mm threads on the rear end and has plenty of them exposed to thread the spider onto. Do Grizzley, Enco, and other import lathes use the same thread here?

thanks,
jerry

I'm confused. Do you mean you're making a spider on the outboard side of the headstock?

 

[carlsbad]

What size jet is it ?

13x40

 

[carlsbad]

I'm confused. Do you mean you're making a spider on the outboard side of the headstock?

Yes.

 

[X Ring Accuracy]

If there is enough of the spindle sticking out, why not drill and tap that?

 

[carlsbad]

spindle has threads beyond the locknut but not past the door that covers the change gears. I'll post photos later.

For those not sure how to check, M50x1.5 is about 17tpi so your US thread gauge should be close to 18tpi but not quite. Major diameter on my spindle threads is about 1.960 but that could vary.

--Jerry

 

[RWO]

Why over complicate it? A slip-on spider with a couple of set screws will work just as well and is a hell of a lot easier to make. No metric thread to mess with!
RWO

 

[carlsbad]

Why over complicate it? A slip-on spider with a couple of set screws will work just as well and is a hell of a lot easier to make. No metric thread to mess with!
RWO

I've added photos now and there isn't much unthreaded length. Metric threads aren't too bad if you use a higher speed. I used about 150 rpm makes them go quicker. --Jerry

 

[butchlambert]

I've added photos now and there isn't much unthreaded length. Metric threads aren't too bad if you use a higher speed. I used about 150 rpm makes them go quicker. --Jerry

Faster speed make better threads? How come?

 

[carlsbad]

If your Acme leadscrew is set up for TPI threads (like most lathes), then you can't use your threading dial and you have to leave the half nut engaged when cutting metric threads. This adds a lot of time. So if you can run a faster speed the reverse trip goes by a lot faster. Faster speeds should work better with carbide tooling and my internal threading bar does use carbide but I didn't see any real improvement at this slightly faster speed. I cut the external threads for my thread gauge with HSS and the cut was better.

--Jerry

 

[butchlambert]

Gee Whizz!!

 

[akajun]

I just found a trick for metric threading the other day, there is actually a YouTube video on it. I used it the other day and it works great.
Thread as you would normally on a certain number on the thread dial, for this lesson say td position 2.
Unlock the half nuts as you normally would at the end of your thread and turn off the lathe, you will see, as expected the thread dial start to rotate again past position 2.
Retract the cross slide and Now run the lathe in reverse until the td is back on position 2 and lock the half nuts until the tool is back at the beginning of your threads. , repeat until you have hit your thread profile .

 

[carlsbad]

akajun, thanks. This lets you use the half nut to stop the thread but you still have to run it backwards to the start of the thread so it doesn't speed up the process any. I was hoping you had a solution that sped up the process.

I use my foot brake to stop at the end of each pass. With a little practice you can shut the lathe off and let it coast down as it gets to the end of the thread and then use your brake to stop it. my brake is very user friendly and I can stop within .005" or so every time. --Jerry

 

[boltman223]

akajun, thanks. This lets you use the half nut to stop the thread but you still have to run it backwards to the start of the thread so it doesn't speed up the process any. I was hoping you had a solution that sped up the process.

I use my foot brake to stop at the end of each pass. With a little practice you can shut the lathe off and let it coast down as it gets to the end of the thread and then use your brake to stop it. my brake is very user friendly and I can stop within .005" or so every time. --Jerry

This is why I love reverse to lead screw on the apron.

 

[butchlambert]

akajun, thanks. This lets you use the half nut to stop the thread but you still have to run it backwards to the start of the thread so it doesn't speed up the process any. I was hoping you had a solution that sped up the process.

I use my foot brake to stop at the end of each pass. With a little practice you can shut the lathe off and let it coast down as it gets to the end of the thread and then use your brake to stop it. my brake is very user friendly and I can stop within .005" or so every time. --Jerry

If you had my Monarch you could do it 3 times as fast, but making a part like that doesn't require speed. Speed is for production and race cars. If speed is your deal, get a 10EE Monarch with ELSR and you can safely thread at 1000 rpm.

 

[carlsbad]

If you had my Monarch you could do it 3 times as fast, but making a part like that doesn't require speed. Speed is for production and race cars. If speed is your deal, get a 10EE Monarch with ELSR and you can safely thread at 1000 rpm.

When I bought my lathe, a Monarch was well out of my price range. I toy with selling it and getting a nicer lathe. Right now my day job is keeping me very busy. Maybe one of these days they will make good on their threats to lay us all off . --Jerry

 

[butchlambert]

Jerry,
10EE lathes are available at a reasonable price if you keep looking. I paid less than $3000 delivered. It came with a 3jaw Tru Adjust, 4 jaw, several backing plates, live center, Albrecht chuck, steady rest, following rest, taper, collet setup, and ELSR. Mine is a 1956 WIAD model. I also got an extra set of vacuum tubes for it. It has a wedge type Aloris toolpost. It is not easy to chamber a barrel in as the headstock is very long and you can only work with a maximum length between centers of 20". You can do it though. I use my 6913 Clausing 14X48 to chamber barrels.
Pictured below is the 10EE just after we moved it into the shop.

Looking from my 10EE at the Clausing.

Looking at my 2 Bridgeports. They do have a VFD on each.

I do have a surface grinder, tool post grinder, tool grinder, 2 pedestal grinders, 2 belt sanders, and a Roll In Saw.
It doesn't take a lot of money, just being able to network with friends and a little patience.

 

[Caleb85]

Faster speed make better threads? How come?

Lol not this guy! 70RPM is about good for me!!

 

[butchlambert]

Lol not this guy! 70RPM is about good for me!!

I agree. I have carbide threading inserts, but get my best work with my Warner HSS inserts. I do this for fun and am not interested in bragging that I chamber at 500RPM. I can do it with the Monarch, but the setup time would eat up the time that I could do it at less than 100RPM. Speed is for production.
Being in the car business I've owned some pretty nice and fast cars. My daily driver now is a Mitsubishi Lancer. Do I like it? No, but it was cheap and is cheap to operate. I drive 75-100 miles a day. Do I like speed? Yes, but now I can get in my youngest Son's CTS/V Cadillac wagon with 565hp. 200hp upgrade is coming out of his pocket.