What's new
What's new

FP-1 X-Axis Nut Question

crpearson

Plastic
Joined
Apr 23, 2017
Location
Santa Cruz
Hey guys, hopefully this will be a quick and easy one. I'm replacing the X axis nut on my FP-1. I just got the new part from Singer and it's not clear to me what the purpose of the small groove going half the length of the nut is for. It seems like something that should interface with a key, but removing the old nut, no key or alignment dog is there. It seems strange that they'd take the time to cut that groove for no reason. Am I missing something?

Anyhow, just wondering what, if any, purpose that groove has? Thanks very much, as always for your help!

IMG_1242.jpg
 
That groove is for oil distribution: the red ring in the drawing attached shows the groove at the top of the nut, with oil flow direction. At least that's how it is on my FP1 twin dial version.
FP1 x-screw nut with groove.jpg
Cheers,
Bill
 
The taper pin holding on the bell crank is rather stuck. I'm worried about bending things or damaging castings. From those of you with experience, would you say this setup is sufficiently supported to safely knock out a stuck taper pin? Is there anything else I should be doing?

As I lower the Z axis onto the support I want to avoid loading it up with too much weight, but also ensure no shock force is transferred to the castings. Anyhow, just hoping for a second set of eyes from you folks who have done it before.

IMG_1246.jpg
IMG_1247.jpg
 
The taper pin holding on the bell crank is rather stuck. I'm worried about bending things or damaging castings. From those of you with experience, would you say this setup is sufficiently supported to safely knock out a stuck taper pin? Is there anything else I should be doing?

As I lower the Z axis onto the support I want to avoid loading it up with too much weight, but also ensure no shock force is transferred to the castings. Anyhow, just hoping for a second set of eyes from you folks who have done it before.

View attachment 247859
View attachment 247860

Hi CR

The two most important things are:

1. Strike perpendicular from the right side with the right sized punch!
2. Strike with the greatest force you are able to deliver, eg at least a 1kg hammer, from the very first strike on.

Your setup looks reasonable. But even without the Z-axis support, you would be safe. It would take much more to damage/bent anything there. I am talking from my own experience. Same pin on my FP1 was stuck like hell.
So give it a bold and fearless blow and let us know.
In my experience trying first a while gently on a already feelingly stuck taper pin only worsens things by mushrooming up the end.

Best,
Stefan
 
Agree with Stefan's comments. Your setup looks good. Definitely lower Z until you have generated some pressure, say 20 or 30kg worth. This won't do any damage to the Z screw or support, and it will provide some additional protection for the end of the shaft and bearings there.

Use a pair of calipers and carefully measure both sides of the taper pin to be sure to identify the smaller diameter side of the taper pin. Then use a big hammer (1-2kg) and HIT IT HARD THE FIRST TIME. Get a friend or colleague to hold the punch for you, so you can use both hands to control the hammer.
 
Stefan and Ballen,

Thank you both very much for the help and advice. I'll get everything setup tonight after work and knock it out of there.
 
You guys were right... It just involved being brave, getting a big hammer and a solid whack. Much more solid than I would have been comfortable with had you guys not talked me through it. I know I'm being a bit tentative about this, but my FP-1 is precious to me and I don't enjoy the idea of hitting it with a hammer. Anyhow, the support worked well, the taper pin is out and nothing is damaged. I should have the new axis nut installed shortly. Thank you again very much for your help and support!

Cliff

IMG_1248.jpg
 








 
Back
Top