15" Rockwell drill press spring tension

[nknirk]

Model 15-081 drill press. Wondering how to set the spring tension and the nuts on the pinion shaft. This version does not have the screw underneath to set the spring tension. I have to set it by hand. It has two nuts on the end of the pinion shaft that secure the spring. If I tighten the nuts firmly to hold the spring tension, then the pinion won't turn or move the quill up and down. If I keep them loose, then the spring loses its tension totally. If I split the difference and leave it a little loose, then the nuts eventually work themselves loose, as the quill raises and lowers, and the spring becomes disengaged again. What am I doing wrong please?

 

[WAS Jr]

Nkirk, pm me with your phone number and I will text you a copy of my 15-081 manual, which came with my machine, still in my possession, which I got as a Christmas present in December 1979. The tension adjusting procedure is straightforward. I am out of town til next week and I will get it to you then.
Regards, Bill S

 

[nknirk]

Nkirk, pm me with your phone number and I will text you a copy of my 15-081 manual, which came with my machine, still in my possession, which I got as a Christmas present in December 1979. The tension adjusting procedure is straightforward. I am out of town til next week and I will get it to you then.
Regards, Bill S

Ok. Thanks I PM’d you. Thank you. I found a manual for the 15-081 online. I don’t know what year it’s from. But unfortunately it describes the tension adjustment by using a screw which is not on my model. Again mine is done by hand. Hopefully your manual has something else. Maybe they added the adjustment screw on later models?

 

[BFBOB]

I have one of these too, which I bought used 35 years ago! There is no screw on mine either. I have adjusted it for use with a mortising chisel, and I don't remember it being particularly difficult, but it's been a long time.
I just took a look at it, and orientation may be the key. The spring cover is oriented so from normal operating position you see the end of the spring hooked over a slot in the cover. Looking end-on to the quill pinion shaft, the slot is at the 2 o'clock position. At the exact bottom of the spring cover, there is another slot. If I remember correctly, it fits over a bump in the casting and prevents the cover from rotating. The quill nuts don't do anything to maintain spring tension, they just keep the spring and cover from popping off the quill shaft. There's almost no force exerted against the spring cover. That's why there is the jam nut arrangement, to keep a single nut from backing off.

I don't think I ever had the manual, but I'll take a look through my archive.

 

[BFBOB]

Try this:

http://vintagemachinery.org/pubs/detail.aspx?id=5837

No mention of a screw to adjust return tension. Dated 1975, about right for mfr date of mine. Not a great copy, but legible.

And here are a couple of pix of the slots and bump I was talking about. Note that you do not move the spring/cover to adjust tension. Just make sure one of the slots is on that lump so it can't rotate. You don't have to remove the spring/cover to do this, in fact I urge you not to. If you popped the spring out of the cover, it would take herculean effort to get it back in! Tighten the jam nuts against each other but make sure they aren't bearing more that very lightly against the spring cover.
Adjusting the tension per the manual, it's a little tricky - once the quill drops below the stop, it has to be held just a tiny bit off the bottom in order to rotate the pinion shaft to adjust tension. If it's down too low it'll jam against the lug on the bottom of the quill; if too high it'll engage the rack. In between you can rotate freely to increase/decrease tension. Don't let the handle get away from you! It can rap you across the knuckles good and proper!

 

[nknirk]

Try this:

http://vintagemachinery.org/pubs/detail.aspx?id=5837

No mention of a screw to adjust return tension. Dated 1975, about right for mfr date of mine. Not a great copy, but legible.

And here are a couple of pix of the slots and bump I was talking about. Note that you do not move the spring/cover to adjust tension. Just make sure one of the slots is on that lump so it can't rotate. You don't have to remove the spring/cover to do this, in fact I urge you not to. If you popped the spring out of the cover, it would take herculean effort to get it back in! Tighten the jam nuts against each other but make sure they aren't bearing more that very lightly against the spring cover.
Adjusting the tension per the manual, it's a little tricky - once the quill drops below the stop, it has to be held just a tiny bit off the bottom in order to rotate the pinion shaft to adjust tension. If it's down too low it'll jam against the lug on the bottom of the quill; if too high it'll engage the rack. In between you can rotate freely to increase/decrease tension. Don't let the handle get away from you! It can rap you across the knuckles good and proper!

Thank you! This is great! IT's definitely the correct manual (as opposed to the other 15-081 manual I've been using). I'll see what I can do with this!

 

[nknirk]

Try this:

http://vintagemachinery.org/pubs/detail.aspx?id=5837

No mention of a screw to adjust return tension. Dated 1975, about right for mfr date of mine. Not a great copy, but legible.

And here are a couple of pix of the slots and bump I was talking about. Note that you do not move the spring/cover to adjust tension. Just make sure one of the slots is on that lump so it can't rotate. You don't have to remove the spring/cover to do this, in fact I urge you not to. If you popped the spring out of the cover, it would take herculean effort to get it back in! Tighten the jam nuts against each other but make sure they aren't bearing more that very lightly against the spring cover.
Adjusting the tension per the manual, it's a little tricky - once the quill drops below the stop, it has to be held just a tiny bit off the bottom in order to rotate the pinion shaft to adjust tension. If it's down too low it'll jam against the lug on the bottom of the quill; if too high it'll engage the rack. In between you can rotate freely to increase/decrease tension. Don't let the handle get away from you! It can rap you across the knuckles good and proper!

OK. I'm starting to get a feel for how to do this. Thank you for the advice and good description!

 

[nknirk]

That did it! I got it fixed! Thank you so much!

 

[BFBOB]

Delighted to be helpful!