Single point threading

jpfabricator

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A 6" vise is overkill for a RF45 style mill. A 4" is more appropiate for that size mill & IMO 5" max. I have a 5" GMT vise on my PM45 & it's slightly too big. Not enough Y axis travel to make use of the 5" full capacity. Better to save your money rather than getting something too big & most importantly the weight. I take my vise of the table quite often, a 6" is still light enough for me to be carried by hand but I'm glad I have a 5". I also have a 4" vise as well. I prefer the 5" though.

But those GMT 6" Premium vises are pretty nice. I'd love to have one but don't need one on my current mill. But if you plan on upgrading to a full size knee mill in the future than the 6" will be perfect.


Here's what the 5" looks like on my mill.
Img_1921.jpg


I couldn't even complete this cut without my bellows & DRO scale getting in the way. Not enough Y travel & the 5" vise is not even maxed out.
Img_7597_zpscb8b5dd7.jpg


Here's what a 6" vise looks like on another PM45 (gt40's)
View attachment 253544
 
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A 6" vise is overkill for a RF45 style mill. A 4" is more appropiate for that size mill & IMO 5" max. I have a 5" GMT vise on my PM45 & it's slightly too big. Not enough Y axis travel to make use of the 5" full capacity. Better to save your money rather than getting something too big & most importantly the weight. I take my vise of the table quite often, a 6" is still light enough for me to be carried by hand but I'm glad I have a 5". I also have a 4" vise as well. I prefer the 5" though.

But those GMT 6" Premium vises are pretty nice. I'd love to have one but don't need one on my current mill. But if you plan on upgrading to a full size knee mill in the future than the 6" will be perfect.


Here's what the 5" looks like on my mill.
Img_1921.jpg


I couldn't even complete this cut without my bellows & DRO scale getting in the way. Not enough Y travel & the 5" vise is not even maxed out.
Img_7597_zpscb8b5dd7.jpg


Here's what a 6" vise looks like on another PM45 (gt40's)
View attachment 253544

9ea93c65d262a95814794c15c74673c8.jpg
 
i like the cross slide a LOT better. but to each his own for sure. i completely agree with that. gotta do it the way it works.
 
I use a threading stop to allow quick retract and reset of cross slide and use the compound to feed in. Before using the cross slide stop it was always a much slower process and easier to accidentally wind back in a few to many thousandths and take a cut that was a bit deeper than i should have.

Sturt
 
Congrats on your success. How about a pic of your setup when you use the compound to advance the tool? Just curious as to what your problem could have been.

BTW, I see a tapatalk red X instead of a pic in your OP, but the link to the photo worked fine.

Tom
 
When I use the compound the threads look like they aren't timed correctly. It's set at 30*, the tool is sharp, and I'm engaging on the same # on the thread counter. It just looks "off".
When I get more time in the shop I will post some pictures of the fails.

Sent from my SM-S320VL using Tapatalk
 
jp, to my mind it is worth getting both methods sorted so you can readily use either depending on the circumstances. Looking forward to seeing your pictures.
 
First, you want the angle to be less than 30 degrees, never more. And that angle is measured from the cross slide direction, not from the spindle axis. Sometimes the degree markings on lathes for the compound angle are laid out measuring from the spindle axis at zero to the cross slide at 90 degrees, which will give you a 60 degree angle to the cross slide if you set it at 30 degrees on the dial. Get the compound pointed directly in line with the cross slide. That should be 0 degrees, not 90. Then swing the compound to the left as you count off the degrees until you get to less than 30 degrees. Anywhere around 29 degrees is probably fine, it is not critical unless it is more than 30 degrees which will leave a stair step finish on the right flank of the thread.
 
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