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spitfire9
02-27-2008, 03:13 AM
I was wondering what would happen if I sprayed some WD40 into a sliding pot ?
Would it screw up the contacts ,, has anyone tried this ?

I have a couple of sliding pots that just seem a bit sticky.

Thanks.

Westozy
02-27-2008, 03:22 AM
They will get stickier! Use some electrical contact spray, "Electroclean" or similar. Oil based lubes will make them worse as it dries out. Or replace them, pots are cheaper than the spray probably!

Gwyn

spitfire9
02-27-2008, 03:49 AM
OK,, I have some electrical contact cleaner.

I'll give that a try.

Lezam
02-27-2008, 10:40 AM
In general, I dont think WD40 would screw up electronics if thats what your asking. I've sprayed some on various parts while they were off, with no immediate failures. Correct me if I'm wrong though.

spitfire9
02-27-2008, 02:19 PM
I was also thinking of that white lithium grease .

I wonder if that would mess up the contacts in the pot?

I have some in a spray can.

465464

I attached a picture of the pot set up.
I am using two pots per lever. One for power and one for reversers.The set up allows the tab to move the sliders forward and a spring to return the slider to neutral.
The reason I am looking at lubricating the pots ,is sometimes the pot is slow to return to neutral ( a little slower than the lever movement) and I really don't want to use heavier springs, for fear of breaking the slider.

Also attached a pic of the quadrant and pedestal so far.

I will be posting lots of pictures in the near future of the Convair 580 project.

737NUT
02-27-2008, 04:41 PM
Toss the slide pots and string pots! :) No maintenance needed.

spitfire9
02-28-2008, 03:57 AM
String pots ??

737NUT
02-28-2008, 08:43 AM
String pots ??

http://www.geocities.com/raflyer/727TQ.html?1202355783531

superconnie
03-16-2008, 05:08 PM
There is nothing wrong with spraying a pot with WD40. They will work again like new. The only problem is that WD40 evaporates and can become sticky. The best experience is to use WD40, move the pot until it works fine, spray it again and blow the excess WD40 away with compressed air.

Or just take a good contact spray.

STRING POTS.... Why has nobody told me about them earlier...??? They would have saved me a lot of time. :o
I took slider pots and a long spring and attached a string to that. Works fine but I had to search for sliders that were long enough.

ve4anc
03-17-2008, 12:36 AM
Spit:

I don't recommend WD-40 as an electrical contact cleaner in critical applications because it gums up and while it may seem to prolong the life of a pot by spraying, it is usually a sign the pot is going south due to wear ... not unlike giving a dying patient a few full lungs of oxygen .. perks things up for a very short time but won't prevent the inevitable.

An exception would be in radio restoration where the part has been sitting in a grungy basement for 40 years and just a film of corrosion needs to be removed on an otherwise low-cycle control.

I'm suprised those new pots would be acting up after so few cycles on them.

My favourite contact cleaner for restoring old radio equipment is "Deoxit." It is available by mail order from a distributor just south of YWG. http://www.backstageproaudio.com/

I'll drive down and pick some up in the next day or so, as I'm down to my last quarter-can and have been using it like Scrooge handing out money to potential welfare recipients.

In the meantime, hold your horses.

Here's an EBaay link to String Pots ... interesting, didn't know they existed. http://cgi.ebay.com/ebaymotors/String-Pot-Position-Sensor-Data-Logging-potentiometer_W0QQcmdZViewItemQQ_trksidZp3286Q2ec66Q2em20Q2el1116QQhashZitem230217953451QQitemZ230217953451

Yer buddy,
VE4ANC

spitfire9
03-17-2008, 01:41 AM
Hi ,,ve4anc !

I recently purchased some spray called "Control Tuner and Lubricant" from Radioshack .It is made for rotary and slide audio pots and such.

I read about it on a different forum ( I can't remember which one) and some guys were using it to good effect.
Apparently when you spray it in the pot ,you are supposed to work the pot back and forth a bit. It will feel a bit gritty at first ( cleaning ,I suppose) then everything is supposed to work better.

The pots are alright,, but as you can see from the picture I attached,, the springs are pulling the slider back to neutral position. I don't want to use heavier springs for fear of breaking the slider arm .
With these springs,, if you cut the throttle or reverser too quickly, the spring ( sometimes ) is a little slower (than the throttle arm) to bring the slider back.

I thought a bit of lubricant every so often would keep it sliding nicely.

I'll post here after I give it a try,, which will be soon.

535

superconnie
03-17-2008, 03:33 PM
I agree... my experience is more with old radios...

If the pot starts to act funny because it was used so much... well then the best would be to replace it.

A good advise will be to use really good pots. I bought some for $20 per piece. They are made of conductive plastic and should have a lifetime of 10'000'000 cycles. We will see if it's true.

superconnie
03-17-2008, 04:44 PM
String pots are cool but $183 is a bit too expensive. They seem to be watertight if you can install it under your car. The most expensive pot I bought was a slider normally used for professional mixing consoles (music) That was about $50. I use it for the rudder pedals.