Belt loose?

[mountain4don]

I have been having a little trouble with my Headstock loosing speed when I run it at the top speed for routing operations. And I opened and cleaned and lubricated the two sheeves as described in the manual. And checked the poly v-belt for tension and it seems a little loose but not bad. But when I check the motor belt to the lower sheeve it is real loose and makes a buzzing noise when I run it at top speed as it vibrates. How do I know when to replace this belt? There doesn't seem to be any way to increase tension on it? And is this some sort of special belt or can I just go to my local belt supplier and buy one?

[SDSSmith]

I have been having a little trouble with my Headstock loosing speed when I run it at the top speed for routing operations. And I opened and cleaned and lubricated the two sheeves as described in the manual. And checked the poly v-belt for tension and it seems a little loose but not bad. But when I check the motor belt to the lower sheeve it is real loose and makes a buzzing noise when I run it at top speed as it vibrates. How do I know when to replace this belt? There doesn't seem to be any way to increase tension on it? And is this some sort of special belt or can I just go to my local belt supplier and buy one?

The sheaves on the motor maintain the belt tension on the motor drive belt. It may be that the motor sheaves are still a little gummed up (not sliding properly) and need a little more lubrication. If they are lubed, sliding properly and you are still experiencing problems, the time for a new belt might be now. The belt is a Shopsmith specific belt.

[wa2crk]

A worn drive belt will measure less thanone half of an inch across the back. A new belt will be about 9/16" across the back. Here is a comparison of an old vs a new belt that I replaced on our woodworking club's Shopsmith.
[ATTACH]18124[/ATTACH]
The new belt is about 3/32" wider than the worn one.
Bill V

[mountain4don]

I measured my motor drive belt and it was only 0.385" wide according to the calipers. And looked kind of smashed. So I ordered a new set of belts including this one and the poly-vee belt. I hope I can get the thing apart to change them out. Its been running with these belts probably since 1981. I looked at one of the sawdust sessions on changing these belts and it talked about removing the eccentric and their being a hex wrench plug below the eccentric clamp bolt. But I looked there and there isn't one. There is just a regular hex head bolt and nut on the clamp around the eccentric. What am I missing there?

[JPG]

I measured my motor drive belt and it was only 0.385" wide according to the calipers. And looked kind of smashed. So I ordered a new set of belts including this one and the poly-vee belt. I hope I can get the thing apart to change them out. Its been running with these belts probably since 1981. I looked at one of the sawdust sessions on changing these belts and it talked about removing the eccentric and their being a hex wrench plug below the eccentric clamp bolt. But I looked there and there isn't one. There is just a regular hex head bolt and nut on the clamp around the eccentric. What am I missing there?

An older Greenie will have a hex bolt, and a really older greenie will have a couple of retaining 'clips' secured by that bolt(actually it is a screw).

A '0.385' width belt will not move to the outer portion of the motor pulley at high speed, and will probably bottom out at slow.

A new belt is waaaay over due! I gots one like that(original from 1962) that was replaced only fairly recently.

[terrydowning]

Mine is the really style old with the retaining clips and a gilmer drive.

[mountain4don]

An older Greenie will have a hex bolt, and a really older greenie will have a couple of retaining 'clips' secured by that bolt(actually it is a screw).

A '0.385' width belt will not move to the outer portion of the motor pulley at high speed, and will probably bottom out at slow.

A new belt is waaaay over due! I gots one like that(original from 1962) that was replaced only fairly recently.

Mine is a 1981 (according to the Shopsmith date charts) and is grey just like my 1984 model. It had the single bearing quill which I replaced recently since it wobbled pretty bad and I couldn't use it for table sawing and drilling or router work like the double bearing quill on my 1984 model. Maybe I better check the belts on my 1984 Shopsmith too? And the 1981 has just the hex bolt clamp on the eccentric. Where might these retaining clips be? Or do I have to unclamp the eccentric and slide it out to find them? Or is there something else I need to do to get the eccentric out of this model?

[JPG]

Mine is a 1981 (according to the Shopsmith date charts) and is grey just like my 1984 model. It had the single bearing quill which I replaced recently since it wobbled pretty bad and I couldn't use it for table sawing and drilling or router work like the double bearing quill on my 1984 model. Maybe I better check the belts on my 1984 Shopsmith too? And the 1981 has just the hex bolt clamp on the eccentric. Where might these retaining clips be? Or do I have to unclamp the eccentric and slide it out to find them? Or is there something else I need to do to get the eccentric out of this model?

Those PITA(Bill Mayo discards them) clips were only used on the early("A" casting ? ) greenies. A retaining screw and washer were added to later versions to replace them.

One end of them would be protruding and hooked over the external end(i.e. visible).

The eccentric should rotate freely with the clamp loosened. Like lotsa stuff that seldom gets moved, it may be stuck. Be advised that the bearing is held in the eccentric by a set screw only accessed from between the ears(bottom looking up) that has a cone tip that rests in a groove around the bearing. That screw/groove prevents the bearing from moving in/out of the eccentric bore.

CAUTION: Do not over tighten either the set screw(exerts excessive pressure on the bearing casing) or the 'ear' screw
(they fracture easily). Just snug the setscrew, and tighten the screw until the lock washer is barely fully compressed.

[terrydowning]

I'll try to remember to take pic of the insides of my eccentric today. It has the PITA clip thingies, while they are a PITA, they do work. On more than one occasion they kept the eccentric from coming out when I have not tightened the bolt tight enough.

[fgrule]

I was confused on this when I first tried to remove the eccentric bushing........This may help:

First image shows eccentric bushing with belt tight and all screws/bolts tight:
[ATTACH]18129[/ATTACH]

Second image shows screw/bolt loose and slot in eccentric at 6:00:
[ATTACH]18130[/ATTACH]

Third image shows large allen screw removed(#502038). You can clearly see smaller allen screw as seen from underside as JPG said, in thickest part of eccentric body, that was not visible before (screw #139367).
[ATTACH]18128[/ATTACH]

Fred