Jump to content
🎄 🎄 🎄 2024 Custom Ornament Business Kit - Now Available - SALE 50% Off Through Dec. 2nd ×
Ornaments For Charity eBook - Designers Wanted! ​​​​​​​🙏 ×

Potentiometer wore out, need one for Delta


LarryEA

Recommended Posts

It's a 40-690 Type1 Delta (Dewalt look-a-like).

Had a switch problem and since I took the switch cover off the variable speed does not work.

Dewalt Tech says I have to order new pc board and it comes with the variable speed control (potentiometer)

 

My variable speed potentiometer (pot) wore out.  (variable speed control)

I don't want to spend $80 for PC Board just to get the potentiometer.

I probably can jury rig a different pot but would like original equipment.

Any ideas where I can get just the original pot?

Edited by LarryEA
Link to comment
Share on other sites

Found my problem, now to get it fixed.

My variable speed potentiometer (pot) wore out.  (variable speed control)

I don't want to spend $80 for PC Board just to get the potentiometer.

I probably can jury rig a different pot but would like original equipment.

Any ideas where I can get just the original pot?

 

Link to comment
Share on other sites

Seriously Larry, with a worn out old pot who knows what is next - I think you need a whole new scroll saw for your birthday tomorrow, not just a new pot.  At our age you have to spoil yourself some as the opportunities are getting fewer and fewer.  I am leaving the "pot" jokes to others.

Link to comment
Share on other sites

Seriously Larry, with a worn out old pot who knows what is next - I think you need a whole new scroll saw for your birthday tomorrow, not just a new pot.  At our age you have to spoil yourself some as the opportunities are getting fewer and fewer.  I am leaving the "pot" jokes to others.

Happy Birthday tomorrow Doug. Thank you and I would enjoy a new saw.

I would still pursue to have this one work. Radio Shack has the VS Switch which I might obtain

on my Birthday.

Again, thanks and my best wishes to you.

Link to comment
Share on other sites

Larry

Scroller on another forum had this situation back in March.  Several of us helped him to find one.  A couple of pots were located but not exact matches but might have worked.  At the end he decided to order the pot/card combo.  His thinking was if the pot went bad how soon before the old card could quit also. 

 

Links we used to locate pot/card under $80.00 in case the RS pot does not work.  (Prices may have gone up by now)

Black & Decker 5140101-32 CB & POT. | Ace Tool Repair $59.13


Pc Board Assy - 5140101-32 - Industrial Tool and Supply $57.20

DeWalt 286308-00 Circuit Board $57.20

DEWALT - BLACK AND DECKER 5140101-32 - PC BOARD ASSY - Part Number 5140101-32 (DEWALT - BLACK AND DECKER ORIGINAL OEM). Smallenginesprodealer.com $50.72

 

Larry

Link to comment
Share on other sites

Larry

Scroller on another forum had this situation back in March.  Several of us helped him to find one.  A couple of pots were located but not exact matches but might have worked.  At the end he decided to order the pot/card combo.  His thinking was if the pot went bad how soon before the old card could quit also. 

 

 

The old card may never quit, it does not have moving parts like the pot does.

I would think the motor would be the next most possible.

Thank you for the links. The lowest price I found was about $65

The Potentiometer is $3.49 at Radio Shack

Edited by LarryEA
Link to comment
Share on other sites

I found out this summer when mine died so I bought a new one after 15years.I was wondering cause if I can buy a used motor I will use the saw as a 2nd saw.Maybe someone has one that has a circuit board gone etc. I will keep looking cause the rest of my saw is still good.The repairman said it wasn't worth buying a new motor when you can buy a whole saw for almost the price of a new one.Thanks for the reply Larry. Damian

Link to comment
Share on other sites

  • 1 year later...

Hi,

My Delta 40-601's control knob stopped working correctly a couple of weeks ago and I just found this thread. Did that Radio Shack part work?? (I realize this is an 'old' post but it's the best lead I've found!)

 

Thanks!

Knob did not work......It ended up to be dust in the switch

Link to comment
Share on other sites

I got in on this thread really late--but:

I spent 20 years at the Shack and would not have recommend that pot for motor use for a couple of reasons:

 

#1 It is a linear pot and is not as accurate as an audio pot of the same rating (in ohms)

#2 It probably would not handle the current and would eventually arc internally and either carbon up or weld itself at one speed.

#3 There is no heat sink if it could handle the current.

 

I understand the pot works with the circuit board to control speed, but somewhere in that line, there has to be some kind of resistance to slow the motor.  Resistance equals heat.

Edited by Jim McDonald
Link to comment
Share on other sites

The potentiometer needed for the DeWalt 788 is a 50 K ohm linear taper. Radio Shack sells one like it with the right physical as well as electrical size for just a couple of bucks, but the shaft on it is too long and there is no flat side for the knob D hole shape. I cut the shaft with a hack saw to make it the same length as the original, then figured out where the flat side needed to be by turning both the new and old potentiometer CCW to the stop. I then filed the shaft of the new potentiometer to create the needed flat on the side of the shaft to fit the D shaped hole of the original knob. Fifteen minutes and the saw was good again for about $3 and a little effort. Your Delta saw likely has the same speed board as the DeWalt. 

 

There is a huge amount of mis-information in this post. If you don't know the right answer, don't post at all.

 

The electronic board takes care of the voltage control and speed of the motor. It electronically eliminates the "Heat" that would be encountered if using an old wire wound potentiometer in series with the motor winding to control the motor speed. The potentiometer used in these modern saws never sees more than a few milliamps of power, and therefore, does not get hot. Wire wound potentiometers for motor speed control went out with the dark ages and trolley cars. Modern electronic circuits like these speed control boards don't wear out. They sometimes go bad when a voltage spike in the power line damages them, but they don't wear out like an old mechanical machine. Most will be around and in perfect working condition until they are technically obsolete and scrapped. The Radio Shack 50 K Ohm linear taper potentiometer even looks like the original, except for the long shaft with no flat. A hack saw and a file make the only modifications needed. An AUDIO TAPER POTENTIOMETER is logarithmic, which means that it is non linear and increases resistance and an increasing rate as the shaft is turned. It WILL NOT  WORK correctly for this application.

 

Charley

I'm a retired (EE) Automation Engineer

Edited by CharleyL
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...