belt squeal or slipping pm3520b

[Ron Oastler]

I have been working on my new lathe with a 19" silver maple large chunk of wood, rounding the bowl to shape and then doing the coring with the oneway system, When I was doing the roughing the belt seemed to slip or squeal and now that I am doing the coring it does it more often, not sure if I am doing things in correctly or not , when I roughed out the block I was at 150 rpms and as it got closer to the desired shape I was at 350 to 400 rpms, and with the coring I have the speed set at 300, I have tried a little higher and also a little lower but seem to have the same problem, I have the belt set on the lower speed range as this blank was very heavy and I started off at a very low speed, any advice would be greatly appreciated, this piece of silver maple has some awesome figure in it and I would like to get 4 bowls in all, I have the centre one out now and I am working on the next one, I will cover the bowl on the lathe tonight and get back at it tomorrow

ron in kingston

[Denis Puland]

Hi I do not have a pm lathe but if the belt is slipping or squealing tighten the belt tension.

Denis

[Art kraft]

Ron, try tightening the belt, if that is not possible go to your local fleet farm store and buy "Pulmore belt dressing" it is a wonderful product. only need a few drops to stop the squeal. You need a lot power to turn that large of a diameter. The outer diameter is traveling at 1990 feet per minute.

[Ron Oastler]

Thanks Denis and Art, being the technical weenie that I am, I hadn't checked the belt for the tightness ( I assumed the belt was factory set maybe it got moved some how during set up here), but I just did check it and adjusted it, man does this thing work great, it went through the next two bowls like nothing, its great that one can come here and ask questions and get super advice, especially for those of us that don't know a hammer from a screw driver, again thanks, I really appreicate it
ron (the guy with many new bowls)

[Reed Gray]

For me, the turning speeds you are using are very slow. Go whatever speed you feel comfortable with, but I would core closer to 500 to 800, and turn in the same range or higher, if the piece is balanced. I just did a demo on a 3520B model after turning on an A model for 8 years (got a Robust now), and the high end speed on the low range is 1250, compared to 1500 on the A model. Too slow for me on the small bowls.
robo hippy

[Kurt Rosenzweig]

No tools are needed to tighten the belt! Just use the 2 levers to the left of the red on/off button! The little lever is the lock down and the big lever is the tension. Just loosen the little one and push down on the big one while tightening back the little one! And as Robo said speed it up some and you'll see a big difference!

[Ron Oastler]

thanks thats exactly what i did, and the difference was amazing, I was able to core out 4 bowl and several platters in a very short time, ron (the happy turner in the mound of shavings)

[Gregg Feldstone]

I got the same squealing on my 3530b while attempting to manually core a bowl. The noise did occur during catches which actually stopped the lathe....I was going at VERY slow speeds of <100. I tightened my belt also.

[Gregg Feldstone]

didn't finish last post....What's the rule of thumb on proper belt tension? The manual doesn't say a lot about this

[Scott Hubl]

When I switch the belt between the 2 pullys I loosen the bolt and let the weight of the motor drop down and then just give a gentle extra push down and then tighten the bolt. No need to go hog wild pushing the motor down hard to tighten the belt.

Of course if you here a squeal or theres slipping you need a little more pressure on the belt.

After that if your still hearing a squeal, a phone call to CS is in order.

[Gregg Feldstone]

Thanks Scott, that's pretty much what I've done.

How bad is it for the motor (lathe in general) to actually stop the spindle from turning when I get a catch?
I don't know if the motor actually stops or the belt just slips on the pulleys at this point. Don't plan on doing it again but I probably will.

[Paul Heely]

If you are stopping the motor itself then the controller should shutdown before any damage is done to the motor. If the belt is slipping then its probably not too good for the belt as it may start to glaze over.

On my PM I've verified that the motor stops if I stall the lathe, intentionally took some big cuts with the pulley door open.

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Paul

[Gregg Feldstone]

When you did this (stall the lathe) did you continue to feel torque when you saw the motor had stopped? I have and that's what worries me. Should I be concerned about this. It hasn't happened often and hope to never do it again, but.....

[Paul Heely]

The motor was still trying to turn. I did not stall it long enough for the controller to shutoff. The controller has parameters that can be programmed to protect the motor from over current and over torque situations. Please don't just take my word for it. Contact WMH tech support and ask them.

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Paul