Bandsaw Motor Wiring

G

Grandpop

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I hauled home my latest auction treasure yesterday, a 1974 Rockwell / Delta 14" Metal/Wood Bandsaw (28-300). Lets just say she was rode hard and put away wet frequently. PO must not have been very mechanical, as see lots of things jerry rigged and or messed up after scraping away worst of the crud.

So first thing, try out the motor to see if it is even worth fixing this beast. Has this tag:
1589931240489.jpeg

and photo that shows the wiring to be

1589931403082.jpeg

a little hard to see, but black tape on white line @ 1, 2 empty, 7 missing. Three wire input (heavy), white, black and green; green to motor ground screw. So that looks like set up for high voltage (230), with red and black reversed (3 and 5).

Hooked it up to 230 outlet with white wire to house red, and black wire to house black. Thought I might have to reverse them, but expected to turn one direction or other. Motor turned, but only about maybe 50 rpm. Not much of an electrical wizard, but pulled the cap out of the cover and saw this

1589931854078.jpeg

Does this make sense, a 110 cap for a 230 motor wiring? Could the cap be why it won't run full speed (turns freely by hand)?

Or am I doing something else wrong?

Thanks for any help,
Ted

1589931240489.jpeg1589931403082.jpeg1589931854078.jpeg
 
the motor appears to be wired for 230v operation.
to run on 230v, the cap should be rated for at least 250v
most likely the cap was damaged when 200+ volts were applied for the first time :(
the motor will have a hard time starting without the cap functioning
 
The way the factory builds them the cap will only see 120 volts if the motor is wired properly whether configured for 120 or 240 v. The cap may have worked for a while and is now dead, or the centrifugal switch inside may be gunked up
-Mark
PS The 110 volt rating is marginal. You would want a minimum of about 165 V. Don't assume the cap you have there is the proper one, someone may have thrown in one they had laying around. A 1 HP motor would normally use a cap of about half that value, maybe 350 MFD @ 200 or 250 volt
There may be limited space under the capacitor cover so keep that in mind when capacitor shopping. Of course you can always mount the cap remotely and run wires over.
 
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It never ceases to amaze me how the folks on here know exactly where to put their fingers to find the old information, thank you! My bandsaw base is slightly different than was shown in the catalog, as has smooth front (not the bumped out cover). I was surprised to see the speed on the motor when the caked on dust was removed, as was expecting 1725, so that is another item that is toast. This $60 purchase is starting to look like a parts machine (missing upper blade guide/guard, both 4 step pulleys, tension adjuster stripped, and haven't even gotten into it yet.
 
$60 is a bargain. In 1970 that saw without a stand or motor had a list price of $423 adjusted for inflation in 2020 that would be $10,870!

You can probably find used original pulleys on Epay but you should be able to use substitutes for less. The speeds may be slightly different. Other parts are available including aftermarket adjusters and blade guides. Except for the pulleys, gearbox and lower wheel many parts are used on the very common wood only version.
 
Thanks Rich. I do see the upper step pulley new for $150, and lower not available. I can make the lower one once I can measure the upper one to make sure the same belt fits all steps the same. So reading the manual at vintage machinery, does not say you have to loosen the motor to change belt pulley steps. Does that mean you are supposed to keep the belts loose enough to be able to change steps without tools but it still drives without slipping?

I most likely would pick one speed for metal (about 150-200 sfm for the hrs/crs I typically use) and keep it set up like that with upper knob in for metal and out for wood. Maybe could just mount 2 - 3 separate pulleys on motor, and 1 -2 on the upper reduction drive to see how it works for cheap before go to the step pulleys.

A rebuilt kit is available on fleabay (upper wheel bearings, tires, guide bearings and table slot filler bolt/plate for $180), $200 for new motor (maybe with vfd), and some more small items for another $200. Might end up about what I see them sell for complete, but should be in deent shape at that point.
 
The two pulleys are #720 and #718. They used the same # pulleys for the 24" Scroll Saw. Unfortunately the pulleys came with bore sizes 1/2", 5/8" and 3/4". Later they gave them unique numbers see page 187 of the catalog link above. It lists the new part numbers as well as the diameters. On my saw the upper pulley is 3/4" bore and the lower 5/8". Shop carefully!

The bearings for the wheels and guides are all standard parts, I suspect you can do better buying them separately. The guide bearings are probably 6200ZZ (replacement for the original 77500) I don't remember what the upper wheel bearings are but nothing exotic.
 
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Rich, I have to admit I stopped reading after the bandsaw section. Can't tell you how many hours I spent looking for those pulley dimensions. Thank you for pointing me back to the catalog; this time I read every page. Also saw the missing on/off switch. Between the catalog and the manuals on vintage machinery, some utube videos, and other rebuild write-ups I found, looks like there is a lot of info out there on there on these saws.

Not that I need one, but looks like I have another project!
 
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