Excalibur speed control going crazy

[Gonzo]

While cutting a project at about 75% speed, the saw suddenly topped out on my Excalibur. I turned the dial to its slowest speed and it seemed fine. I slowly increased the speed and all of a sudden it went to the fasted speed. 
Does anyone have any ideas on why and what to do.

[munzieb]

It's possible that the rheostat/controller may be dirty or some of the windings internally may be worn. There are postings "rheostat" that may help.

[OCtoolguy]

Sounds like a dirty rheostat to me also. Blow it out with a can of compressed air. Maybe get a can of contact cleaner too. If it turbs out to be a bad rheostat, that's an easy fix too. Out of curiosity, is your saw a Chinese Ex or one of the earlier saws? 

[rash_powder]

As mentioned it is likely the rheostat.  Sometimes they get a bad spot in them from being used in the same spot always.  Turning it back and forth sometimes help, but it will likely need blown/cleaned out or replaced.  Digikey is a good place to source parts like that.  

[Gonzo]

T

5 hours ago, OCtoolguy said:

Sounds like a dirty rheostat to me also. Blow it out with a can of compressed air. Maybe get a can of contact cleaner too. If it turbs out to be a bad rheostat, that's an easy fix too. Out of curiosity, is your saw a Chinese Ex or one of the earlier saws? 

How does one go about cleaning the rheostat? And where is it?  Sorry I’m kind of dumb when it comes to mechanical crap. 
Good question Ray!  I have no idea if it’s Chinese or not. I bought it off Craig’s list 6 years ago. It maybe had 5 hours on when I bought it. How can I find out if it’s the Chinese or earlier saw?

Edited August 10, 2022 by Gonzo

[OCtoolguy]

12 minutes ago, Gonzo said:

T

How does one go about cleaning the rheostat? And where is it?  Sorry I’m kind of dumb when it comes to mechanical crap. 
Good question Ray!  I have no idea if it’s Chinese or not. I bought it off Craig’s list 6 years ago. It maybe had 5 hours on when I bought it. How can I find out if it’s the Chinese or earlier saw?

Look at the i d  plate at the right rear by the motor. It should say either Canada, Taiwan or China. What color is your saw. If it's green it's definitely a good one. Black can be either Taiwan or China. If you bought it used 6 years ago I'd say it's not Chinese. 

As to cleaning the rheostat try blowing it out with high pressure air. Preferrably the stuff you buy for computers. It's dry air. No moisture. While blowing it out wherever you can get air into it you'll want to be rotating the knob or shaft to dislodge any dirt/dust/corrosion. If after doing that you still have a problem you might have to unsolder the wires from it and take it to an electronics supply store to get a new one. But, don't get in over your head. If you can't do it try to find someone who can.

[Gonzo]

I have 2 EX-21’s. I have never bothered to look to see where they came from. But then again, I’ve never had any trouble.  Both are made in Taiwan. Both saws are 6 years old,  The one in question only gets used in the Spring and Fall, which is very little, compared to the other. 
when I got home from work today, I played with it and took the canned air to it. It seems to be working correctly.
Thank you all for your help!  I appreciate it!!!!

[OCtoolguy]

1 hour ago, Gonzo said:

I have 2 EX-21’s. I have never bothered to look to see where they came from. But then again, I’ve never had any trouble.  Both are made in Taiwan. Both saws are 6 years old,  The one in question only gets used in the Spring and Fall, which is very little, compared to the other. 
when I got home from work today, I played with it and took the canned air to it. It seems to be working correctly.
Thank you all for your help!  I appreciate it!!!!

You'ave got 2 great saws. I'm glad that you may have found the problem. I also have 2 of them and I try to remember to "exercise" the speed controls on both of them as often as I can remember. I don't change cutting speeds very much but I give the knobs a back and forth twist just to keep any corrosion from building up. I live a mile from the Pacific ocean so it's humid here year round.

 

[kmmcrafts]

If you or anyone cannot solder in a new one Seyco sells a replacement with the cord and plug in on it so it's just plug and play. But that said you'll need to take more of the saw apart to access the plug end of it to the circuit board.  

[crupiea]

I had a car that did that when it rained.  Makes using it a bit more challenging and exciting!!

[tomsteve]

On 8/10/2022 at 5:10 PM, Gonzo said:

How does one go about cleaning the rheostat? And where is it?  

thats your speed control knob. i had to replace mine when it did the same. easy repair even for people not mechanicallly incined.

if there isnt a vdeo in YT, we can guide you through it

Edited August 12, 2022 by tomsteve

[OCtoolguy]

6 hours ago, tomsteve said:

thats your speed control knob. i had to replace mine when it did the same. easy repair even for people not mechanicallly incined.

if there isnt a vdeo in YT, we can guide you through it

Give Ray a call at Seyco.com. He should be able to supply the part.