Motor Foot Control

[Burdekin]

How hard is it to add a foot control to this setup? https://www.ebay.co.uk/itm/120W-150...rentrq:9760ab8116e0a9cce03e730fffe79770|iid:1

Anyone know of any instructions of how to do it?

 

[WorkshopChris]

In its simplest form take a tig foot pedal and replace the pot with one the same value as in the control unit, unsolder the wires and extend or add a master remote switch. But there may be many small problems to overcome.

 

[hotponyshoes]

As workshopchris says...
A 3-way 3-pole switch (presuming there are 3 wires on the pot in that box) if you want to use both controls frequently
If you dont want to swap them that often then you could put a socket onto the back of that box that you plug the foot control into and wire the original box pot onto a flying lead (might work out cheaper just to buy the switch though)
Or, if you only want to use the foot control then you could just take the pot out of that controller and use that on a longer cable.

Tig foot controls are expensive but last in a workshop environment.
Other options are making a diy one, sewing machine ones, drum kits, wahwah pedals, industrial foot switches for electrical or pneumatic control or even racing car pedals for a pc/xbox type thing might be a cheap starting point.

I dont foresee many problems, electrical interference maybe depending on what the foot control wire runs near, if it's for a welding positioner then high frequency from the arc may be an issue.
Cable length might also cause some issues with voltage drop but depending on the application if you find it's running a bit slower than intended you might just be able to turn it up a bit more!

 

[hotponyshoes]

If you look through all the photos in the ebay listing or do a google search with the part number you might even be able to find a wiring diagram of the controller before buying it.
That would show you if it's easy to do or not.

If there is anything fancy inside that control box that you dont want to replicate you could just make a pedal up and attach that box to the side of it and have the movement of the pedal turn the existing knob.

 

[Burdekin]

Thanks guys. These are what I am going to replicate, finally getting round to it. The WNS one just looks like it uses two foot pedals.

https://www.ebay.co.uk/itm/WNS-Powe...493498?hash=item340246cbba:g:XgkAAOSwBRZcXYdg

http://www.lazzemetalshaping.com/in...product_id=7/category_id=3/mode=prod/prd7.htm

 

[hotponyshoes]

I have used both types of those.
They use 2 different control systems.

The top one has 2 pedal switches. One makes it turn forward and one in reverse. There is a speed pot on the stand for adjusting the speed.

The other has a single pedal with the speed pot in it (from off to max) and then a forward/reverse switch on the column.

They are both a pain to use. Ideally you want the twin pedals with speed control on each of them.
With the single pedal version I had thought about extending the fwd/rev switch onto a lead so you could use it at the same time as holding a sheet of metal but never got aroundtuit. The pedal on it was fixed to the base which was also a pain if holding larger sheets.

I currently have the version with twin pedals, I miss having the speed control on the pedal but, not done anything about that either.
I did think it might be simple enough to fit some sort of ramp-up box so it starts off slowly when you press the pedal then increases speed but I have not looked into it yet.

Ideal would be to have 2 pedals with on/off and speed in each one. Should just need an extra pot and maybe a couple of interlock switches to stop the magic smoke if you step on both pedals at once.

 

[Hopefuldave]

A lot of VFDs have an option (programmable) to put a "stopped" dead zone in the middle of the control potentiometer range (often called "joystick" mode, good for hoists, cranes etc.) and full forward and reverse at opposite ends so you could rock a pedal from forward to reverse - may be similar available for DC motor drives (that looks like an AC motor though)? The control box in the original post doesn't show a reversing switch, if you think you'll need one...

Dave H. (the other one)

 

[mike 109444]

Consider going DC.
If you can get the drive unit from a mobility scooter. Lots of torque AND can be set to free wheel (for manual starting) Note would pay t work out the sort of speed the bead rollers will need to run at for normal use (it will be very slow !)
You would need to disable the diff in the drive unit.

 

[m_c]

Going by what's provided in that first ebay listing, I'd guess it's actually a DC motor, and the speed controller will be a pretty basic SCR controller.
It's a pretty reliable setup, but be aware if you're tinkering, the speed control pot wiring will have mains voltage on it, so don't go holding wires with bare hands just to test things.

Also, try and find some max torque figures for the gearboxes. They're maybe high ratio, but I'd have my doubts as to if the motor would stall or the gearbox would go bang first, if you do stall the output shaft.

 

[gaz1]

 

[Dcal]

I went the 3phase motor and inverter route with a foot pedal form a Roland electric piano.
It works a treat, with forward and reverse on a switch and variable speed on the pedal.
I used chains and sprockets to get the speed down to close to the motors normal speed range and it has huge torque.
The motor and gear box was bought from the forum as was the inverter.
The pedal was £30 odd I think and the most expensive bits were the gears and sprockets which wasn't that much.

https://www.mig-welding.co.uk/forum/threads/yet-another-bead-roller-mod-thread.85196/#post-1225874

 

[Burdekin]

I have an old stairlift motor/gearbox tucked away somewhere, might see what it is first then.

 

[Johnnybravo]

I used a geared down electric wheel chair motor on mine. Running two server power supplies daisy chained together to get 57A @24v. Then got a speed controller off eBay for less than a tenner. Speed adjustable not on the pedal. Use a 24v relay to give me forward and reverse using two simple foot pedals. I think speed control on the pedal is a waste of time,trying to keep a certain position with you foot whilst trying to guide an unwieldy sheet of metal at the same time,is never going to happen...

 

[mike 109444]

Check any motor you use to see if it has a saftey clutch/brake that would need removing before applying power!
The mobility scooter motor did and I would have expected stair lift to as well.
The motor I used was feed from a 24v supply and speed control via an ebay DC controller (< £15 if I recall) Two foot switches one fwd one rev. When under load, beading some test steel it was drawing only 8 amps max.

 

[Dcal]

I think speed control on the pedal is a waste of time,trying to keep a certain position with you foot whilst trying to guide an unwieldy sheet of metal at the same time,is never going to happen...

I find the speed control very useful, especially if I'm rolling something that has long straights and tight curves on the same piece.
Keeping the speed to what you want is as simple as driving an auto car.
Having the speed control range adjustable on the inverter is also a nice feature which helps as you can have the speed range as wide or narrow as you want.

If the foot pedal is on a fly lead (why would you have it any other way?) you can place it or move it to suit any size / shape of panel.
With my eyesight being able to see the line dictates where I stand more than anything.

A sea-saw design foot-pedal with stop in the middle and forward reverse either way would be another nice to have but I don't miss it, flicking the switch to change direction works fine for me.

 

[Johnnybravo]

Check any motor you use to see if it has a saftey clutch/brake that would need removing before applying power!
The mobility scooter motor did and I would have expected stair lift to as well.
The motor I used was feed from a 24v supply and speed control via an ebay DC controller (< £15 if I recall) Two foot switches one fwd one rev. When under load, beading some test steel it was drawing only 8 amps max.

Safety brake very easily removed.

 

[Wallace]

Mobility scooters have most of the required bits, a forward and reverse switch with variable speed plus the E-brake to stop the motor running on. I’m currently looking at a few to see what might be suitable for my stalled bead roller project.

 

[Burdekin]

Mobility scooters have most of the required bits, a forward and reverse switch with variable speed plus the E-brake to stop the motor running on. I’m currently looking at a few to see what might be suitable for my stalled bead roller project.

Thanks. If only I still worked near Mablethorpe that would be ideal. :-)

 

[Johnnybravo]

You don’t need an E brake to stop it running on. If you use a dc motor, just short the motor terminals together with a relay when not powered. Stops in its tracks. Simplifies things as you don’t need to energise an e brake before supplying power to the motor.

 

[Screwdriver]

How hard is it to add a foot control to this setup? https://www.ebay.co.uk/itm/120W-1500rpm-Gear-Reduction-Adjustable-Speed-CW-CCW-Motor-Gearbox-Governor-NEW/352688434050?_trkparms=aid=111001&algo=REC.SEED&ao=1&asc=20160908105057&meid=a8af809c7c6f428c9db4bc57ba4b0698&pid=100675&rk=2&rkt=15&sd=113957683870&itm=352688434050&pmt=1&noa=1&pg=2380057&_trksid=p2380057.c100675.m4236&_trkparms=pageci:43b578be-0dcb-11ea-b34a-74dbd1807d98|parentrq:9760ab8116e0a9cce03e730fffe79770|iid:1

Anyone know of any instructions of how to do it?

If you don't want to mess about with the electronics, fit a pulley wheel to the potentiometer shaft. Then drive the pulley with a foot operated, spring loaded 1/4 wheel segment.

Looks like the potentiometer needs about 270 degrees of travel so you "can't" just use a crank but there must be a thousand ways you can drive the pot mechanically. I recommend 4mm urethane round belt. Super cheap, easy to join and will grip a V pulley with even the lightest of tension.