Speed adjustment, can't get to low end?? ..
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- UncleSnick
- Gold Member
- Posts: 37
- Joined: Mon Apr 07, 2014 8:36 am
- Location: Bethelehm, PA Nick's 'Nuthin Fancy'
Speed adjustment, can't get to low end?? ..
Hi all,
While rebuilding my shortie I didn't make any adjustment to the high speed set screw so I didnt do a speed adjust when I reassembled. I was using it a few days ago and it just sounded fast. So last night I got out my Tach and the low speed was 1150 RPM!. So checked that the sheaves are well oiled and free to move, keys are in place, etc and then I went about doing a speed adjustment. The top end has no problem reaching 5200 RPM (which I really done need) but the low end can't get below 875 RPM. Even when I unplug and manually work the driven sheave to where the v-belt is near the OD of the driven sheave and the motor sheave is about as wide as it goes, I can't seem to get it to run below about 870 RPM. According to the website, I should be able to reach 700 RPM at 'SLOW'. I was stumped but didn't have time to dig into further last night. Will get at it again in another few days. I'll also tach my other units to see exactly what they're doing when at 'SLOW'. I'd be appreciate knowing what you did if you've ever encountered this situation or have any ideas.
- Nick
While rebuilding my shortie I didn't make any adjustment to the high speed set screw so I didnt do a speed adjust when I reassembled. I was using it a few days ago and it just sounded fast. So last night I got out my Tach and the low speed was 1150 RPM!. So checked that the sheaves are well oiled and free to move, keys are in place, etc and then I went about doing a speed adjustment. The top end has no problem reaching 5200 RPM (which I really done need) but the low end can't get below 875 RPM. Even when I unplug and manually work the driven sheave to where the v-belt is near the OD of the driven sheave and the motor sheave is about as wide as it goes, I can't seem to get it to run below about 870 RPM. According to the website, I should be able to reach 700 RPM at 'SLOW'. I was stumped but didn't have time to dig into further last night. Will get at it again in another few days. I'll also tach my other units to see exactly what they're doing when at 'SLOW'. I'd be appreciate knowing what you did if you've ever encountered this situation or have any ideas.
- Nick
My shop is my time machine. I go there and lose all sense of time!
Greenie Serial 293128 March 1955
Greenie Serial 300735 August 1955 - Bad shape, future restoration project.
Grey Serial SS102778 Sept 1981 - Reversible shorty SPT driver.
Grey Serial SS168100 Feb 1984
Band saw Serial SS48432 Sept 1981
4" Jointer Serial SS91521 Nov 1985
Jigsaw Serial 33556 Jan 1984
Greenie Serial 293128 March 1955
Greenie Serial 300735 August 1955 - Bad shape, future restoration project.
Grey Serial SS102778 Sept 1981 - Reversible shorty SPT driver.
Grey Serial SS168100 Feb 1984
Band saw Serial SS48432 Sept 1981
4" Jointer Serial SS91521 Nov 1985
Jigsaw Serial 33556 Jan 1984
- JPG
- Platinum Member
- Posts: 34648
- Joined: Wed Dec 10, 2008 7:42 pm
- Location: Lexington, Ky (TAMECAT territory)
Re: Speed adjustment, can't get to low end?? ..
Is the 'Motor' belt OEM(i.e. from Shopsmith?)
P.S. Is the belt < 1/2" wide?
P.S. Is the belt < 1/2" wide?
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Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
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Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
- UncleSnick
- Gold Member
- Posts: 37
- Joined: Mon Apr 07, 2014 8:36 am
- Location: Bethelehm, PA Nick's 'Nuthin Fancy'
Re: Speed adjustment, can't get to low end?? ..
I snapped a quick picture but didnt measure. The belt is a 504193. It's an older belt but looked to be in good shape so I reused it. I believe the current number is different.
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My shop is my time machine. I go there and lose all sense of time!
Greenie Serial 293128 March 1955
Greenie Serial 300735 August 1955 - Bad shape, future restoration project.
Grey Serial SS102778 Sept 1981 - Reversible shorty SPT driver.
Grey Serial SS168100 Feb 1984
Band saw Serial SS48432 Sept 1981
4" Jointer Serial SS91521 Nov 1985
Jigsaw Serial 33556 Jan 1984
Greenie Serial 293128 March 1955
Greenie Serial 300735 August 1955 - Bad shape, future restoration project.
Grey Serial SS102778 Sept 1981 - Reversible shorty SPT driver.
Grey Serial SS168100 Feb 1984
Band saw Serial SS48432 Sept 1981
4" Jointer Serial SS91521 Nov 1985
Jigsaw Serial 33556 Jan 1984
- JPG
- Platinum Member
- Posts: 34648
- Joined: Wed Dec 10, 2008 7:42 pm
- Location: Lexington, Ky (TAMECAT territory)
Re: Speed adjustment, can't get to low end?? ..
Correct belt. Appears 'normal' width.UncleSnick wrote:I snapped a quick picture but didnt measure. The belt is a 504193. It's an older belt but looked to be in good shape so I reused it. I believe the current number is different.
So that path is non-fruitful.
Since the belt positioning on the pulleys is 'normal' I am suspect of the tach. The motor is highly unlikely to be running fast especially 25% so.
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Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
╟JPG ╢
╚═══╝
Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
- UncleSnick
- Gold Member
- Posts: 37
- Joined: Mon Apr 07, 2014 8:36 am
- Location: Bethelehm, PA Nick's 'Nuthin Fancy'
Re: Speed adjustment, can't get to low end?? ..
Thanks for the tip JPG. Now the plot thickens ...
I thought I'd verify the tach against a known entity. So I tach'ed the motor shaft and got 3580 PRM which I thought was fairly close to a 3600 RPM motor. But when i looked at the nameplate, it said the output should be 3450 RPM! So I was getting a reading 104% of nameplate. So the tach might be off but doesn't fully account for the 24% increase in speed I am seeing at the Quill.....
I had to put it back together to use it Sunday afternoon so I just adjusted the speed indicator wheel to match the RPM I was reading so I don't overdrive my bandsaw. But now the lowest I can mechanically go is about 'C' on the dial.
I'd gladly pull it apart and fix it if I knew what the problem was ....
I thought I'd verify the tach against a known entity. So I tach'ed the motor shaft and got 3580 PRM which I thought was fairly close to a 3600 RPM motor. But when i looked at the nameplate, it said the output should be 3450 RPM! So I was getting a reading 104% of nameplate. So the tach might be off but doesn't fully account for the 24% increase in speed I am seeing at the Quill.....
I had to put it back together to use it Sunday afternoon so I just adjusted the speed indicator wheel to match the RPM I was reading so I don't overdrive my bandsaw. But now the lowest I can mechanically go is about 'C' on the dial.
I'd gladly pull it apart and fix it if I knew what the problem was ....
- Attachments
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- IMG_3352.jpg (134.92 KiB) Viewed 4334 times
My shop is my time machine. I go there and lose all sense of time!
Greenie Serial 293128 March 1955
Greenie Serial 300735 August 1955 - Bad shape, future restoration project.
Grey Serial SS102778 Sept 1981 - Reversible shorty SPT driver.
Grey Serial SS168100 Feb 1984
Band saw Serial SS48432 Sept 1981
4" Jointer Serial SS91521 Nov 1985
Jigsaw Serial 33556 Jan 1984
Greenie Serial 293128 March 1955
Greenie Serial 300735 August 1955 - Bad shape, future restoration project.
Grey Serial SS102778 Sept 1981 - Reversible shorty SPT driver.
Grey Serial SS168100 Feb 1984
Band saw Serial SS48432 Sept 1981
4" Jointer Serial SS91521 Nov 1985
Jigsaw Serial 33556 Jan 1984
- JPG
- Platinum Member
- Posts: 34648
- Joined: Wed Dec 10, 2008 7:42 pm
- Location: Lexington, Ky (TAMECAT territory)
Re: Speed adjustment, can't get to low end?? ..
Tell me some 'details' about the tach sensing revolutions.
╔═══╗
╟JPG ╢
╚═══╝
Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
╟JPG ╢
╚═══╝
Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
- UncleSnick
- Gold Member
- Posts: 37
- Joined: Mon Apr 07, 2014 8:36 am
- Location: Bethelehm, PA Nick's 'Nuthin Fancy'
Re: Speed adjustment, can't get to low end?? ..
Hi JPG,
I'm using a Shimpo Tach. I took a picture of how I checked the quill shaft speed. I did the same on the motor shat before I reassembled it. I also shot a picture of the certification. Seems it's almost 12 years overdue for a re-calibration.
I'm using a Shimpo Tach. I took a picture of how I checked the quill shaft speed. I did the same on the motor shat before I reassembled it. I also shot a picture of the certification. Seems it's almost 12 years overdue for a re-calibration.
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- IMG_5502.JPG (124.42 KiB) Viewed 4314 times
My shop is my time machine. I go there and lose all sense of time!
Greenie Serial 293128 March 1955
Greenie Serial 300735 August 1955 - Bad shape, future restoration project.
Grey Serial SS102778 Sept 1981 - Reversible shorty SPT driver.
Grey Serial SS168100 Feb 1984
Band saw Serial SS48432 Sept 1981
4" Jointer Serial SS91521 Nov 1985
Jigsaw Serial 33556 Jan 1984
Greenie Serial 293128 March 1955
Greenie Serial 300735 August 1955 - Bad shape, future restoration project.
Grey Serial SS102778 Sept 1981 - Reversible shorty SPT driver.
Grey Serial SS168100 Feb 1984
Band saw Serial SS48432 Sept 1981
4" Jointer Serial SS91521 Nov 1985
Jigsaw Serial 33556 Jan 1984
- JPG
- Platinum Member
- Posts: 34648
- Joined: Wed Dec 10, 2008 7:42 pm
- Location: Lexington, Ky (TAMECAT territory)
Re: Speed adjustment, can't get to low end?? ..
What is the laser detecting/responding to?
Reflective strip, flag, ...?
Reflective strip, flag, ...?
╔═══╗
╟JPG ╢
╚═══╝
Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
╟JPG ╢
╚═══╝
Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
- RobertTaylor
- Platinum Member
- Posts: 560
- Joined: Mon Sep 03, 2007 9:28 am
- Location: North Canton, Ohio
Re: Speed adjustment, can't get to low end?? ..
Look closer JPG. Do you see the shaft touching he coupler? Think mechanical, not digital.
- BuckeyeDennis
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- Location: Central Ohio
Re: Speed adjustment, can't get to low end?? ..
The speed rating listed on an induction motor is the "full-load" speed ... in this case about 96% of the 3600 RPM "synchronous speed". The motor speed decreases with load, fairly linearly, and 4% "slip" is typical at rated continuous output power. If you measure the speed at no load, however, it should be pretty close to the synchronous speed. So there's no reason to suspect gross inaccuracy of your tach.UncleSnick wrote:Thanks for the tip JPG. Now the plot thickens ...
I thought I'd verify the tach against a known entity. So I tach'ed the motor shaft and got 3580 PRM which I thought was fairly close to a 3600 RPM motor. But when i looked at the nameplate, it said the output should be 3450 RPM! So I was getting a reading 104% of nameplate. So the tach might be off but doesn't fully account for the 24% increase in speed I am seeing at the Quill.....
I had to put it back together to use it Sunday afternoon so I just adjusted the speed indicator wheel to match the RPM I was reading so I don't overdrive my bandsaw. But now the lowest I can mechanically go is about 'C' on the dial.
I'd gladly pull it apart and fix it if I knew what the problem was ....