Search found 20943 matches

by dusty
Wed Aug 10, 2022 10:49 am
Forum: Maintenance and Repair
Topic: Mark V Speed Control
Replies: 118
Views: 2573

Re: Mark V Speed Control

If the motor spring will not let that dimension get to 2.08, then that should explain why people cannot get to 700. Mystery solved? As for the belt dropping inbetween the sheaves on the low speed end, I think that could happen but only for a narrow or worn belt (the belt width shown is a full .59&q...
by dusty
Wed Aug 10, 2022 8:56 am
Forum: Maintenance and Repair
Topic: Mark V Speed Control
Replies: 118
Views: 2573

Re: Mark V Speed Control

For those of us who are measuring geometry within the headstock, the attached drawing is supplied. Shows what the drive geometry should look like, and measure, when running around 700 RPM and using the "Official Shopsmith Belt". All the circled dimensions should be measurable from within ...
by dusty
Tue Aug 09, 2022 4:14 pm
Forum: Maintenance and Repair
Topic: Mark V Speed Control
Replies: 118
Views: 2573

Re: Mark V Speed Control

Here is a graph of the speed data I provided earlier: 520 Speed Chart.png Nominal is from the speed chart, Main (RPM) is measured, Main @3450 is projected speed at the full load speed of the motor. In this case I calibrated the speed dial at K using the tach, as opposed to the method used in high s...
by dusty
Mon Aug 08, 2022 6:07 pm
Forum: Maintenance and Repair
Topic: Mark V Speed Control
Replies: 118
Views: 2573

Re: Mark V Speed Control

Dave I need help that I hope you can provide. I am attempting to understand the differences between your numbers and mine. If you would do the following for me it would help me greatly in getting to the understanding. What I would like to know is this: With the speed dial set so that your idler sha...
by dusty
Mon Aug 08, 2022 1:16 pm
Forum: Maintenance and Repair
Topic: Mark V Speed Control
Replies: 118
Views: 2573

Re: Mark V Speed Control

You may observe that almost all 'discussions' involving trying to gain greater understanding of the beast will include the same participants roaming here. Not all come to the same conclusions however. But all gain by their involvement. Your observations are spot on but I have come to the conclusion...
by dusty
Fri Aug 05, 2022 5:09 pm
Forum: Maintenance and Repair
Topic: Mark V Speed Control
Replies: 118
Views: 2573

Re: Mark V Speed Control

Thanks. That is about as close as I would hope given what we are dealing with. But I still don't understand the big differences.
Study the Four Sheaves at 2156 rpm Quill.jpg
Study the Four Sheaves at 2156 rpm Quill.jpg (163.42 KiB) Viewed 79 times
by dusty
Fri Aug 05, 2022 10:37 am
Forum: Maintenance and Repair
Topic: Mark V Speed Control
Replies: 118
Views: 2573

Re: Mark V Speed Control

Dave I need help that I hope you can provide. I am attempting to understand the differences between your numbers and mine. If you would do the following for me it would help me greatly in getting to the understanding. What I would like to know is this: With the speed dial set so that your idler shaf...
by dusty
Thu Aug 04, 2022 5:15 pm
Forum: Maintenance and Repair
Topic: Mark V Speed Control
Replies: 118
Views: 2573

Re: Mark V Speed Control

Very interesting. Thank you.

My machine numbers are much different . I have not taken a thorough set of readings like yours but I have enough to see that I have work to do. Maybe my machine can get to 700 if I do a better job of maintenance. Thanks again.
by dusty
Tue Aug 02, 2022 12:19 pm
Forum: Maintenance and Repair
Topic: Mark V Speed Control
Replies: 118
Views: 2573

Re: Mark V Speed Control

Tiny differences in measurements will make a surprising difference in calculated results. I am talking third decimal differences. Measuring accurate
operational radii is very difficult.
by dusty
Sun Jul 31, 2022 3:54 pm
Forum: Maintenance and Repair
Topic: Mark V Speed Control
Replies: 118
Views: 2573

Re: Mark V Speed Control

I consider the high speed stop's only function is to preclude the control sheave from interfering with the speed control parts by opening the pulley too far. There might well be another purpose, but every thing else in the drive train is mushy.(wear, belt stretch. . . .) I agree but that does have ...