Looking to make a variable speed dryer. I understand that I need a DC motor and converter to make it variable speed. All of the DC motors I see have a 2 number specification such as " 6-20 VDC MOTOR" Non give an rpm designation. What do the two numbers indicate?? (I'm mechanically challenged)

Mike (Southgate, MI)
If I don't want to, I don't have to and nobody can make me (except my wife) cuz I'm RETIRED!!

That's simply the voltage range that it needs to work. "VDC"= Voltage D.C.

Not sure about the converter, unless it's simply to convert your 110VAC (house current) to 6-20VDC. These are common in 110VAC to 12VDC, like you would use to power up a car stereo, CB, etc... from a wall plug.

If you can get your hands on an AC motor, a simple light dimmer (reostat) will work for you as long as your motor's wattage is less than the capacity on the dimmer. You can get plug-in units from places like Rockler & Woodcraft, but they're overkill for a little motor like that. they're rated at 13-15amps, where a little gear motor will run at under 1 amp.

Mark Griffin
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C&M Custom Tackle
San Dimas, California



Edited 1 time(s). Last edit at 11/22/2006 09:33PM by Mark Griffin.

Mark,

Every time this comes up here, All of the electricians say that using a dimmer or rheostat on an AC motor will quickly burn it up. Are you saying that I can plug my 30 rpm motor into a dimmer switch or rheostat and make it vairiable and I can run it at say 8 rpm if I want? That would be too easy LOL!!!!

Mike (Southgate, MI)
If I don't want to, I don't have to and nobody can make me (except my wife) cuz I'm RETIRED!!

Mike,
I went down to the local electrical store and purchased acontrol box called a Rheostat. It has a knob on it and you can adjust the rpm from barely turning to pretty close to I would say around 120 RPM's per minute on mine. They set me up with a small motor basically the same size as the one that I have on my American Tackle Rod Wrapping Machine. I just turn the knob clockwise for faster rotation and counterclockwise for slower rotation. I use it for drying and to spin the blank faster when epoxing the reel seat arbors in place.

Capt. Marvin Engel

Marvin,

You said that they set you up with a small motor. Was it AC or DC??

Mike (Southgate, MI)
If I don't want to, I don't have to and nobody can make me (except my wife) cuz I'm RETIRED!!

Mike,

I spent years servicing Power Tools and the variable switches in a drill for example are nothing but a rheostat. The voltage on these goes from 0-110V which is what's varying the motor speed. An INDUCTION motor (like a furnace heater) won't work this way (whole other story) , but the dial on power wrappers is nothing but a rehostat and that's the same type of "universal" motor that we're talking about.

Mark Griffin
[]
C&M Custom Tackle
San Dimas, California



Edited 1 time(s). Last edit at 11/22/2006 09:43PM by Mark Griffin.

wow mike both you and i just learned somthing very interesting. Thanks mark thats very good info makes building your own drying motor a snap

That's almost to good to be true for me, Mark! Nothing I do ever comes out that simple! Thanks Mark, Marvin.

Mike (Southgate, MI)
If I don't want to, I don't have to and nobody can make me (except my wife) cuz I'm RETIRED!!

Mike,
The whole setup is 110volt. The motor, rheostat everything. I just had them match up everything so I would not overload anything or burn the house down.
Mike, My e-mail address is: BigMCharters@yahoo.com

Marvin

Mike,

It is my understanding that if the motor is brushless, a rheostat wont' work. If the motor has brushes, then it is capable of running at a lower voltage than 110 and up to 110. All a rheostat basicly is, is a voltage regulator. The more voltage, the more speed.

TJ

Ya know what Mike, he's right about the brushes... I HAVE run brushless motors (permanent magnet field) off a variable speed foot pedal though. I used to run a brushless off a foot pedal to apply finish prior to my power wrapper days. Once the finish was on, the foot pedal came out and the dryer was plugged straight into the wall, so I don't honestly know if there would have been any long term effect. The motor on your wrapper which is running off a rheostat HAS brushes (under the two little black caps), as does a drill motor, Dremel, etc... A brush type motor is called a "universal motor", which is more than likely what Marvin has.

Mark Griffin
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C&M Custom Tackle
San Dimas, California

It figures!! I knew it couldn't be that easy. How do you know if a small motor has brushes or not? Do the little gear motors, timer motors, etc have brushes. What about DC motors? Does this apply to them also?

Mike (Southgate, MI)
If I don't want to, I don't have to and nobody can make me (except my wife) cuz I'm RETIRED!!

70% of the time, there will be two plastic caps located 180 degrees from each other, which make changing the brushes possible w/o cracking the motor case open. notice I said 70% of the time... It's not a rule. The lack of these caps doesn't make the motor brushless. A brush is a piece of carbon usually mounted on a spring. This is the electrical "contact' to the armature's rotating commutator.

Gear motors are a mixed bag, but most that are "industrial" will have brushes serviceable from out side of the motor. Can’t speak for timer motors…


Mark Griffin
[]
C&M Custom Tackle
San Dimas, California

Mike, I connected one of those little slow RPM motors to a footpedal and all it did was switch the motor on & off and had no effect on RPM. I don't think the little gear motors have brushes. I suspect DC motors might require some sort of voltage regulator for DC motors. I hope someone knowledgable about rigging up DC motors will set us straight.

Stan

Mike,
I looked at my motor after reading the above replies. My motor that is hooked up to the small rheostat box does have brushes. I do not know much about electrical, that is why I had the electrical supply store expert set me up so I would be compatable with what I wanted. I even took my rod wrapping machine in my pick up bed to show them what I was going to use it for. I did not want something that would be way more than I needed voltage wise. I use to work in a machine shop years back and there was a set up with a rheostat but on a large scale size to rotate Drill Collars while they were being welded. That is where I got the idea several months back about using a rheostat to operate a small motor that I could control the rotation speed. I forgot to mention the cost. The whole setup cost me $110 total. It was a little expensive but it works very well.

Marvin

Marvin,

Are you running your chuck direct off the shaft or using a belt and pully setup? Do you think it would work on a direct drive system, or does it still turn too fast even with the rheostat?

TJ

Mike would a 40 rpm motor ac work for you? drop me a line if it will and I will see if my local surplus store has any left

Marvin;
Would you mind running a parts list with manufacturers and model numbers for us?

Just insanely curious! Why in the world would anyone take the TIME, EFFORT and EXPENSE of fabricating a drying motor and stand when nearlY all of the vendors can ship one quickly and really rather cheaply. A few years ago I spent weeks and a small fortune getting spare gear motors from TV camera zoom lens power units - why? - because my Norton had the Vendors List on this site hidden I did not even know the stuff existed. Everybody talks about the value of their time when working on rods and pricing - hours spent chasing parts is also a cost.

Gon Fishn

The issue is the variable speed Bill. The only stand alone variable speed finishing set-up that I'm aware of is Flex Coat's and I think the $150 price tag is what makes people start scratching their heads and trying to concoct their own. The $150 price tag really isn't bad considering the fact that it has 100% U.S. made heavy duty parts.

I'm guilty of the same thing. It's perceived value. I see something that's a good idea or a real time saver, then get the sticker shock after seeing the price and the lil’ wheels in my head start turning...


Mark Griffin
[]
C&M Custom Tackle
San Dimas, California