Search found 1684 matches

by Torch
Wed Mar 23, 2022 8:00 pm
Forum: General Discussion
Topic: Help identifying and duplicating this thread.
Replies: 43
Views: 22595

Re: Help identifying and duplicating this thread.

I finally got around to installing the new pair today. The new nut does not thread onto the old leadscrew and the old nut does not thread on the new leadscrew. The new leadscrew fit the machine perfectly, although the end of the new leadscrew was tapped 5mm instead of 4mm, so I had to dig out a new ...
by Torch
Wed Mar 09, 2022 3:50 pm
Forum: General Discussion
Topic: Help identifying and duplicating this thread.
Replies: 43
Views: 22595

Re: Help identifying and duplicating this thread.

New shaft is definitely a different thread form. Straighter flanks, flat root and slightly rounded at the corners. Still 30°included angle, 8TPI and 20mm OD though. New: https://picturehosting.verhey.org/hq800v/Lead_screw/03new_.070_depth.jpg Old: https://picturehosting.verhey.org/hq800v/Lead_screw/...
by Torch
Tue Mar 08, 2022 2:57 pm
Forum: General Discussion
Topic: Help identifying and duplicating this thread.
Replies: 43
Views: 22595

Re: Help identifying and duplicating this thread.

Got the parts today and the shaft was indeed included with the superseded nut. So if you need a new shaft, buy the assembly -- it's cheaper!

At first glance, unmagnified, the thread looks square a the root. I'm at work but will have a look on the OC tomorrow.
by Torch
Sat Feb 19, 2022 2:16 pm
Forum: General Discussion
Topic: Help identifying and duplicating this thread.
Replies: 43
Views: 22595

Re: Help identifying and duplicating this thread.

The first one lasted 2 or 3 years, IIRC. When I changed it, I realized that the slot milled lengthwise down the shaft across the threads left sharp edges that wasn't doing the brass nut any favours, so I dressed the corner on each edge of each thread on the steel shaft with a file to dull the edges....
by Torch
Sat Feb 19, 2022 12:41 pm
Forum: General Discussion
Topic: Help identifying and duplicating this thread.
Replies: 43
Views: 22595

Re: Help identifying and duplicating this thread.

My long term plan is to make one out of bearing bronze instead of brass.
by Torch
Sat Feb 19, 2022 9:22 am
Forum: General Discussion
Topic: Help identifying and duplicating this thread.
Replies: 43
Views: 22595

Re: Help identifying and duplicating this thread.

Yes, it's thoughtful. I just have reservations about accuracy. I think it odd that 1. The original nut (only) was listed with the identical description of "CROSSFEED SCREW W/NUT ASSEMBLY" as the replacement. 2. The screw itself is still listed separately as a stand-alone replacement, and 3...
by Torch
Fri Feb 18, 2022 7:03 pm
Forum: General Discussion
Topic: Help identifying and duplicating this thread.
Replies: 43
Views: 22595

Re: Help identifying and duplicating this thread.

Never heard back from Grizzly, so I tried again. This time they replied in a day: We appreciate your continued patronage with Grizzly Industrial and are glad that you have turned to us for your part needs. The factory can only produce them as an assembly. The nut may or may not fit your current cros...
by Torch
Sat Feb 12, 2022 7:57 am
Forum: General Discussion
Topic: Help identifying and duplicating this thread.
Replies: 43
Views: 22595

Re: Help identifying and duplicating this thread.

NP317 wrote: Thu Feb 10, 2022 11:40 am As for Grizzly, give them a phone call for help answering your parts questions.
They are historically very responsive to customers asking for tech help.
Not so responsive to e-mail. 2 days later and not even an acknowledgment that they received it.
by Torch
Thu Feb 10, 2022 9:58 pm
Forum: General Discussion
Topic: Help identifying and duplicating this thread.
Replies: 43
Views: 22595

Re: Help identifying and duplicating this thread.

Yeah, the carriage lead screw/half nut is another metric/inch hybrid, but larger diameter. That was available from the factory in either 6tpi (inch machine) or 4mm (metric machine). I haven't looked at the thread profile under magnification (it's encased in protective spiral steel sleeves to keep th...
by Torch
Thu Feb 10, 2022 8:14 pm
Forum: General Discussion
Topic: Help identifying and duplicating this thread.
Replies: 43
Views: 22595

Re: Help identifying and duplicating this thread.

Bill, I'm pretty sure you are on the right track. Not necessarily about forcing people to return for spare parts, I suspect that bit was just a lucky coincidence. I suspect the machine design was originally in metric and the Chinese were looking for an expedient way to make a version with inch dials...
by Torch
Thu Feb 10, 2022 5:37 pm
Forum: General Discussion
Topic: Help identifying and duplicating this thread.
Replies: 43
Views: 22595

Re: Help identifying and duplicating this thread.

I'm having trouble finding exact specs on knuckle threads. Machinery's Handbook failed me! One site says they are rounded square threads, with a radius of 1/4 of the pitch in both root and on crest. Another says they have a 30° included angle. Looks like the crest of the external thread does not go ...
by Torch
Thu Feb 10, 2022 4:59 pm
Forum: General Discussion
Topic: Help identifying and duplicating this thread.
Replies: 43
Views: 22595

Re: Help identifying and duplicating this thread.

The thing that argues against acme is the 40° included angle.