Ryobi WDS1600 speed control

[kdosbun]

OK, so I am a first time poster here. I have actually created this account because I have run into an issue and was hoping that some kind soul would be able to assist. I purchased a used WDS1600 a few years back. The main power switch has been replaced and there was no speed control. Just a whole in the box where one would be. When turned on, both he drum and the belt function, I just cannot adjust the speed of the belt. I originally assumed there was a problem with the circuit board and it had been bypassed. After finally deciding to see if there was something I could do about this, I open the control box to find the circuit board still intact. Looking at the wires, it does not look like any wires were modified or moved other than the two wires that would normally lead to the pot switch to adjust the speed, were twisted together and the pot switch was gone. I can only assume that the original pot switch had gone bad, and instead of replacing it, it was just bypassed.

Does anyone know what size potentiometer is needed for this? I have looked at all the replacement part sites and many of them have the circuit board and it comes with the potentiometer. However, I don't want to buy a $50 part to get a $.75 pot switch. All the sites use the same crappy picture, so I am not able to make out any information. I have been searching the web for about a month now trying to find information but have hit a wall every time. I am hoping someone here has opened the speed control of their WDS are are able to assist... Many thanks in advance...

Ken

[atgcpaul]

Does anyone know what size potentiometer is needed for this? I have looked at all the replacement part sites and many of them have the circuit board and it comes with the potentiometer. However, I don't want to buy a $50 part to get a $.75 pot switch. All the sites use the same crappy picture, so I am not able to make out any information. I have been searching the web for about a month now trying to find information but have hit a wall every time. I am hoping someone here has opened the speed control of their WDS are are able to assist... Many thanks in advance...

Ken

Ken, welcome to the site. I'll try to sneak into the garage and take a picture of mine before I enter the chaos that is my house. If the dogs rat me out, then it will be later tonight. Stay tuned.

Paul

[atgcpaul]

I definitely underestimated how complicated this would be. It seems like there's an access panel on the bottom of the variable speed controller, right? If that's how you got to it, it's going to be a couple of days because my sander is bolted to a cart which is behind a bunch of junk in the shop.

[JimD]

If your tool uses a universal motor (i.e. if it has brushes) you could just use a separate speed controller. I have an old Ryobi R 500 router in my router table (actually just the motor) and it has no speed control. When I need to use a large bit at reduced speed, I plug in a speed controller and plug the router to that. Works fine.

[atgcpaul]

If your tool uses a universal motor (i.e. if it has brushes) you could just use a separate speed controller. I have an old Ryobi R 500 router in my router table (actually just the motor) and it has no speed control. When I need to use a large bit at reduced speed, I plug in a speed controller and plug the router to that. Works fine.

I guess that could work, but would be inconvenient. There's one switch on the speed controller box that simultaneously starts the conveyor belt and the drum motor. To use the router speed controller, you'd have to separately switch each motor.

[Pappy]

My controller was bad when I bought mine years ago. Ryobi sent me a replacement and it came with the circuit board as a unit.

[capncarl]

My Jet 10-20 drum sander has separate controls for the drum and conveyor. I suppose that the hours it takes to get the belt to conveyor to track you wouldn't want the drum running. I do not see why a separate controller couldn't be used on the ryobi if the original is not readily available.
capncarl

[kdosbun]

I definitely underestimated how complicated this would be. It seems like there's an access panel on the bottom of the variable speed controller, right? If that's how you got to it, it's going to be a couple of days because my sander is bolted to a cart which is behind a bunch of junk in the shop.

Unfortunately, It is a lot of work to take apart the speed control unit for the belt. The circuit board on my machine checks out. As far as I can tell, everything is OK there. The issue I have is the pot switch. This is the part that attaches to the dial. the pot switch connects to the circuit board via two long wires wires. The pot switch is then attached to the top of the control box using a nut on the outside of unit.

Thanks everyone else for the suggestion of a separate speed control. This is a possibility, but if I can just get the specs on the pot switch, it's like a $.75 versus $20+ and modification.

All the replacement part websites that have speed control parts sell the circuit board and pot switch as one unite... for $60 or so....

Again, thanks everyone for taking the time to reply.

Ken

[woodturner]

The issue I have is the pot switch. This is the part that attaches to the dial. the pot switch connects to the circuit board via two long wires wires. The pot switch is then attached to the top of the control box using a nut on the outside of unit.

The wires are currently connected together, right? So we know that 0 ohms of resistance, a short, is safe for the unit.

Try a 10 K ohm pot. The pot should have three terminals, connect the center terminal and one end terminal to the wires, leave the other end terminal unconnected. Try it and see if the speed range is what you want. If not, increase the size of the pot, maybe try a 100K. Higher resistance will give you more speed range but less "precision", so it will be harder to adjust for a specific speed (but you probably don't care in this application).

Pots are cheap, a dollar or two at an electronics supply house. Probably can find something that will work at the box stores if you don't have an electronics place local. Could also salvage one from an old radio or TV.

[capncarl]

I've had several variable speed controls fail recently and it has been the resistors not the pot. Luckily the one on my Jet drum sander was under warranty. The others all showed signs of resistor failure and were easy and cheap to repair.

[woodturner]

I've had several variable speed controls fail recently and it has been the resistors not the pot.

Were the resistors burned? That's often a sign the resistors are undersized for power - they used a 1/4W resistor instead of a 1/2W resistor, for example. I have noticed that with car parts in the last couple of years, such as the "pulse control module" (wiper speed control) on GM cars. Last one I replaced had gotten so hot it melted the solder and the parts fell out. Back in the day we designed using "worst case analysis" (WCA) but that does not seem to be the case sometimes anymore, especially for aftermarket parts and smaller manufacturers.

In OPs case, the pot is missing, so it is at least the pot, but the resistors could be an issue as well as you note.

[capncarl]

I believe that the resistors were undersized on the Jet. I'm thinking that the replacement has larger resistors and 4 rather than 3. Not sure how the ryobi controls work but the Jet has separate switches of the drum and conveyor, and it is easy not to turn the conveyor completely off when finished. This could result in the machine setting idle for a long time with the conveyor powered up in a stall situation, causing the electronics to overheat and fail. This potentially costly failure has taught me to also unplug the drum sander when I shut it off. (Something that I now do with all my power cords when I finish or leave the shop, after a couple of battery charger melt downs.)