How warm should table saw pulleys get?

LancsRick · 9 Jun 2018

Happy Saturday all!

I've nearly finished getting my startrite 175 up and running and wanted to check something...

It currently has the standard 1.1kw motor fitted, with new belts. I've set the belt tension to allow a quarter turn between finger and thumb with firm pressure which I understand is the right way to go - it has eliminated any belt slip under load at least. The bearings seem ok - both motor and blade spin freely without belts and give no noise or abrasive feeling. No slop in anything.

Having run the saw for ten minutes continuously or so I decided to check all was still well, and it was, but the pulleys (both) were definitely heated up. I could hold my hand against them but would say "hot" rather than "lukewarm".

No, not having had a proper saw before, is this normal or a point of concern? I will be upgrading the motor soon regardless, but wanted to check I wasn't going to transfer an issue to the new one if this was indicative of a problem I should solve first.

Cheers!

sunnybob · 9 Jun 2018

The quarter turn sideways is for bandsaw blades, not pulley belts.

Same as a car fan belt;
find the longest run between pulleys, pull up in the centre of that run. then push down. 1 and a half inches would be fine, do not go tighter. 2" would be considered loose. but loose is better than tight.

LancsRick · 9 Jun 2018

Ok thanks I'll have a play with them tomorrow. Before I was getting a fair amount of slip when I put the blade under load so it sounds like I've gone too far the other way!

Cheers sunnybob.

sunnybob · 9 Jun 2018

start with it loose. if it slips, increase the tension by a very small amount. if it slips, increase the tension by a very small amount. and on and on and on till it stops slipping. Then measure as I said, and keep that distance written down somewhere close to the saw for the next belt (but you might never need another belt).

LancsRick · 9 Jun 2018

Thanks, that's what I was going to do based on this experience. New territory for me as I've not had a belt driven one before!

Myfordman · 10 Jun 2018

It is also important that the pulley are dead in line. Otherwise the belt rubs excessive on the sheaves of the pulley and creates heat.

Look for differences in temperature between the motor pulley and the blade pulley. Hotter motor pulley could be heat conducted along the shaft which is not a problem as modern motors are typically rated to run at 60C above ambient. ie too hot to touch unless you have an arctic workshop. Hotter at the blade end, might suggest overtightening and or bearing problems.

LancsRick · 10 Jun 2018

Cheers for the replies guys. I don't know whether belts need to bed in or something but I backed the tension right off and it still seems to be running fine now, no slippage. Definitely had it too tight before, it's cooler now. Everything is nicely aligned as far as I can tell.

gwr · 8 Sep 2019

Hi sorry to drag up an old thread LanksRick I was just wondering if you can remember the belt sizes as I'm needing replacements and cant find reference to the size anywhere.