Bought used CS70, won't start. SOLVED! Not stupid.

[Ruben Phrisius]

This is my first post on this forum.

I recently got a very good deal on a CS70 EB saw table in my neighborhood yard sale.
The machine looks good but the table is covered in wood glue, which will need some thorough cleaning.

Now the guy gave me 100% guarantee that the machine was in good condition and it worked yesterday when he plugged it in, he said. (I got his name, phonenumber)

I take it home, plug it in, doesn't work. Switch box gave a buzzing noise when pressed off. So I by-passed the switch box and plugged it in directly. I got some sort of clearly distinguishable "click" sound. But nothing happened.

So I open up the motor. Circuit board looks clean, coil looks clean and doesn't smell burned. Carbon brushes were too deep in to take out but looked okay.

Now I am starting to think that I am just missing something. Like an extra safety switch or some safety thing, that it will only operate if this and that is allright.
I feel like doing a bit of research before I call the guy and get my money back. The deal was very good so I don't mind throwing in an extra 100, if I need to.

Any ideas? Appreciate it!

 

[mattfc]

I presume you have pressed the stop button to make sure the NVR switch has reset? I am not sure what other safety interlock switches there might be

Also link to the manual below

http://webmanual.festool.com/index.php?CHAPTER=2666&L=2701&sLanguage=English

 

[Ruben Phrisius]

Thanks for replying!

I read the manual but couldn't find anything useful. Is there a troubleshoot guide for this machine?

And yes, I pressed the buttons many times in all sorts of ways and patterns (like twice green, twice red then green, harder, softer, longer, wiggly).
And more importantly, I bypassed the switch by taking the cord out of the box, put a plug on it and plugged it in and all I got was this click.

So it is not only the switch.

 

[Billnut]

You mentioned that it was in your neighborhood.  Could you go back to the person you bought it from and ask him for some help?

Bill
Bonetto's Carpentry

 

[festoolviking]

Just browsed quickly thru the manual. Do you have the saw connected to a 16A circuit?

Festoolviking

 

[Ruben Phrisius]

You mentioned that it was in your neighborhood.  Could you go back to the person you bought it from and ask him for some help?

Bill
Bonetto's Carpentry

Yes, he's coming tomorrow with the guy that has the company that owned the machine to check it out.
I just don't completely trust their competence, as I don't completely trust mine, so I'm here for second- and additional opinions.

 

[Ruben Phrisius]

Just browsed quickly thru the manual. Do you have the saw connected to a 16A circuit?

Festoolviking

I have a standard (Dutch) household fuse box with all 16a/500v fuses. I think that's okay right?

 

[mattfc]

I doubt it the fuse if the thing is still clicking.. can you rotate the blade by hand ok,  just wondering whether the blade was changed or something and one of the safety mechanism for the blade change is cutting in?

 

[Ruben Phrisius]

I doubt it the fuse if the thing is still clicking.. can you rotate the blade by hand ok,  just wondering whether the blade was changed or something and one of the safety mechanism for the blade change is cutting in?

The blade rotates okay, but that is indeed the direction I am looking in- something else that needs to be screwed tight, pressed, connected. Some sort of safety measure that I overlooked...

 

[PeterA]

I have a CS50 which sometimes won't start if the blade is fully elevated, it might be worth experimenting with the blade height and trying again

 

[Ruben Phrisius]

I have a CS50 which sometimes won't start if the blade is fully elevated, it might be worth experimenting with the blade height and trying again

Good point, I heard it before, nonetheless, I tried it up and down and in the middle.

 

[festoolviking]

I copied some of the text from the manual (see below). I agree that the power source probably isn't the issue. I guess that the saw is NOT in the set-up position, I guess the saw won't run in that "mode". Just trying to help  [embarassed]

6.2 On/Off switch
 We recommend using a 16 A fuse because of the performance of the motor.

7.2 Set-upposition
Always move the saw to set-up position before making any adjustments:
The saw is locked in rest position on delivery.
Turn the rotary knob [2-6] anticlockwise to re- lease the lock and pull the saw forwards.
Push the stop lever [1-7].
The saw is locked in the front position.

Festoolviking

 

[Mettes]

I have a CS70, never had a problem to start it.  There are no safety switches when you open the saw to change a blade or something like that.  The other electronics, besides the switch, are the overheating protection, engine brake and engine speed dial.  
Have you tried to change the speed?  Even all the way down it should still run, but you can give it a try.  Overheating is not something you need to reset manually, the saw should run fine after it had time to cool down.  I have no clue how  the electronic brake works.

Carbon brushes are a possible cause,  but I have to admit I never had to change mine.

Good luck with it, I hope you get it fixed.  It's a great saw, if it runs that is...

 

[AlexThePalex]

I also have the CS70 and have to concur what Mettes says, there are no other safety switches besides the main switch. I never had a problem starting it. You can start the machine in any position. If yours won't start there's clearly a mechanical problem somewhere. If you're lucky it's only the brushes, but I give that a very small chance.

If your switch buzzes that's an indication there's something wrong there. I believe the CS70 has an induction motor, I am not sure if you can attach it directly to 220v or that you needs the circuit inside the switch for proper operation.

 

 

[Slappy]

I hope you didn't pay much for the tool , Used power tools are sooooo much a risk  way worse that even a used car  I M O

 

[Mettes]

Slappy,

I have to disagree on this, at least with my experiences, so far  ...

I buy most of my tools second hand, never had a single problem with it.  My CS70 was bought second hand, I think I own it now for almost 8 years, perfect in every way.  Payed a little more than half of the new price, well worth the savings in my opinion.

 

[AlexThePalex]

Again I have to agree with Mettes. Most of my Festools were bought used and I never have a big problem with any of them. Of course there are some precautions you have to take. For instance, I want to hear and see every tool running before I buy it. I would never just take the sellers word for it that it works, I want to experience it first hand.
 

 

[oldie]

Just curious - I'm not familiar with the machine.

After the NVR switch bypassed.
The click was from within the motor housing - yes?
Is there some sort of 'over-load' protection relay within the motor housing?

Wondering if sold due an intermittent problem with the machine.
Did they say why selling?

Richard.

 

[Ruben Phrisius]

POSSIBLE SOLUTION
So me and my mate opened up the motor again, to rule out possible worn carbon brushes.

The Cs70 manual mentions:
"The machine is equipped with special self-disconnecting carbon brushes. If they are worn, the power is interrupted automatically and the machine comes to a standstill"

The brushes seemed suspiciously short and there was a tiny springed pin sticking out (see photo). We ran the pin and brush with a multi meter and they made no contact. So we're assuming that this pin protrudes when the brush is half way worn and prevents the actual brush from connecting with the motor. Thus disconnecting the whole thing.

What do you guys think about it? Does the picture show a worn carbon brush?

 

[TOOLTOWN]

You got it, that is a safety built into the brushes.

I'm sure your local dealer, or festool rep can find new ones for you.

Ken