Thread: Table saw no go

Does it spin up if you give it a twirl by hand.

WAIT - Stop - remove the belt and then turn it on and give the motor pulley a twirl.
It could be the centrifugal switch is not closing properly - they sometimes get dusty/corroded etc

Thanks Bob,
I shall give this a try let you know how it goes.
Regards Rod.

Which wires were you jiggling? The cable into the switch or the wires into the motor?

Sounds like a dodgy connection - likely leading to the start winding. The centrifugal switch could also be the culprit, but wouldn't have it's dramas solved by jiggled wires.

or the switch is full of saw dust

Hi Guys,
The jiggling of wires that made a difference was to do with the switch it would just not start and simply jiggling the wires to the switch would fix it so the switch needed replacing next time it wouldn't start was different and was trying to start but just buzzed and didn't start just buzzed for a moment so switched off straight away. I had an electrician come and replace the switch and the same thing is still happening so he said the capacitors needed replacing I have done this and still the same. How do I clean/check the centrifugal switch?
Regards Rod.

Originally Posted by Rod Gilbert

How do I clean/check the centrifugal switch?

Check it by the method I indicated in the post above.
Given you have replaced the switch and the caps- if it now starts every time you spin it by hand then it's the centric switch.

Checking depends on motor wiring.
If enough external wires are available someone that knows what they are doing may be able to check the centrif switch from outside the motor otherwise the motor has to be disassembled.
Clean and checking wiring continuity will involve disassembly - unless you are up for it I suggest taking it to a motor rewinder for checking.

Provided that the caps supplied were the right size, then yes, you likely have an issue with the centrifugal switch. It's normally located on the inside of the rear cover of the motor (the front being the end that the pulley is mounted on the shaft).

That level of teardown is normally pretty easy, the greatest trick is being able to gently lever the end cases off (once you undo their retaining bolts) without damaging them - I normally use a pair of long screwdrivers.

You could (as a bit of a hail mary) spray some contact cleaner into the back of the motor as you turn it by hand (with the power off and disconnected). That'll depend on how old it is and if the switch is exposed to the outside or, as is more likely to be the case, it is housed within the "sealed" section of the motor (in which case it's pointless to try).

Originally Posted by Rod Gilbert

Hi all,
... so I have replaced the 2 existing ones with 1 as advised by power tool repairer, connected it up and still the same problem any suggestions out there.
Regards Rod.

Wait a minute, what do you mean replaced 2 with one? Is that a dual cap in the single package or removed both the start and run cap and replaced them with a single capacitor? That does not sound correct.

Also, note that the capacitors are of different type so you need to get the capacitance, voltage and type correct.

John

Ok I removed the fence/rails and top off the saw so I could get to the belts and removed them and pushing start and spinning the pulley and it starts up over and over no problem and switching off and restarting while still spinning down and away it goes again. I guess I will have to get the electrician back again it can take some doing as we are 45ks from main centre.
John the 2 caps were linked together 2 wires coming from the motor into the first and 2 wires connecting the 2 together the guy at repair shop gave me 1 cap with the equal value of both and I asked the question if one was start and the other run and was told no the 1 was all that was needed.
Regards Rod.

Originally Posted by Rod Gilbert

Ok I removed the fence/rails and top off the saw so I could get to the belts and removed them and pushing start and spinning the pulley and it starts up over and over no problem and switching off and restarting while still spinning down and away it goes again. I guess I will have to get the electrician back again it can take some doing as we are 45ks from main centre.

Sounds like the centrifugal switch.

John the 2 caps were linked together 2 wires coming from the motor into the first and 2 wires connecting the 2 together the guy at repair shop gave me 1 cap with the equal value of both and I asked the question if one was start and the other run and was told no the 1 was all that was needed.
Regards Rod.

I've seen that before.

Thanks for the advise I pulled the saw down this morning and took the motor into the repairer today and got it back this afternoon very happy with the service as I have said before it is a 90k round trip to town so asked if possible to get done today while I was in town and they got it done for me. As suggested the centrifugal switch was chock full of dust, so now I just have to get it back in it's a real heavy lump.
Regards Rod.

Originally Posted by Rod Gilbert

Thanks for the advise I pulled the saw down this morning and took the motor into the repairer today and got it back this afternoon very happy with the service as I have said before it is a 90k round trip to town so asked if possible to get done today while I was in town and they got it done for me. As suggested the centrifugal switch was chock full of dust, so now I just have to get it back in it's a real heavy lump.
Regards Rod.

Thats good you found the problem - time to upgrade the dust control on the saw maybe?

Cheers Bob,
The motor is inside the cabinet and it has taken 20years to fill. I have a outlet at the bottom of the cabinet which is pretty inefficient it clears some but not all dust from inside the cabinet and I have built a new over blade guard with 100mm brush to the bottom edge and a hose coming off the back top and it works quite well to my surprise can't be used all the time mainly when doing a narrow cut as there is not room between the blade and the fence with the brush on the table but mostly it works very well indeed.
Regards Rod.

Yep table saw dust collection is a PITA! I've even converted my opening to a 6" duct in the hope that will solve matters and although somewhat better it still does not eliminate about 30% of the heavier dust. The dust is still getting into nooks and crannies inside the table saw (I have a fully enclosed cabinet saw).

i wonder if the method that is used in the Saw Stop table saws with the shroud around the bottom of the blade makes a difference??

cheers