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tweake
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spent the other day getting annoyed at my tig foot pedal not reducing amps or turning off every so often. to the point it nearly went airborne across the room.
so i pulled it apart and found something a tad weird.

inside its an accelerator pedal assembly out of a vehicle. probably a forklift or truck. big chunky steel bracket, with parts cut off to make it fit. its actually hall effect sensor, which is good, but uses a poorly made adaptor board which is not great.
but the main problem is they mounted it up the wrong way. so all the heavy weight is on the foot side and the light side is the floor side. so when you lift off the pedal it tends to lift off the floor instead and consequently not work.

today i had some more stainless pipes to weld up, so i flipped the pedal upside down and it works perfectly.

so now i have to work out how to flip it internally, or find a better pedal.
tweak it until it breaks
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Very curious what brand of pedal you have?
Bill - Tig-O/A-arc
tweake
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wweld wrote: ↑Wed Dec 17, 2025 10:59 pm Very curious what brand of pedal you have?
unbranded, came with the machine. its local branded, euro style machine but no idea where it was made.
tweak it until it breaks
tweake
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https://www.boc.co.nz/shop/en/nz/gtaw-t ... acdc-p-111

thats the machine and its gone way up in price.
tweak it until it breaks
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That's a nice looking machine with awesome specs. Always curious on machines, there are so many and all seem so similar.

My TIG is a oddball WeldPro AC/DC200 it's been good to me so far (I've had it several years now) one of my reasons I got it is the distributor offered a SSC pedal as an accessory. The pedal that came with the machine is still in the box.

Good luck with your pedal upgrades, show some pic's if your up for it when you get to it
Bill - Tig-O/A-arc
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tweake,

Out of curiosity I looked up the pedal shown on the site you had referenced. The photo there sure looks like the operator is using it "upside" down to the way a pedal of this package design is used.

https://www.boc.com.au/shop/en/au/boc-s ... d#product1

interesting
Bill - Tig-O/A-arc
Jack Ryan
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tweake wrote: ↑Wed Dec 17, 2025 11:42 pm https://www.boc.co.nz/shop/en/nz/gtaw-t ... acdc-p-111

thats the machine and its gone way up in price.
It's been dropped from the lineup in Australia. The pedal provided here was the typical "big lump of iron" but on the inside it contained a controller from something else and it used digital control. I'm not sure that an analogue (with a pot) foot pedal can be used with it. I tried to get an SSC pedal but the response was basically, no pot, no pedal.

The supplied pedal was crap, but the machine was fine.

Jack
tweake
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Jack Ryan wrote: ↑Fri Dec 19, 2025 8:44 pm
tweake wrote: ↑Wed Dec 17, 2025 11:42 pm https://www.boc.co.nz/shop/en/nz/gtaw-t ... acdc-p-111

thats the machine and its gone way up in price.
It's been dropped from the lineup in Australia. The pedal provided here was the typical "big lump of iron" but on the inside it contained a controller from something else and it used digital control. I'm not sure that an analogue (with a pot) foot pedal can be used with it. I tried to get an SSC pedal but the response was basically, no pot, no pedal.

The supplied pedal was crap, but the machine was fine.

Jack
i will have to see what voltage range it puts out.
typically the pots versions do the same thing, use the pot as a voltage divider and output a certain voltage range.
hopefully just a simple measure of what voltage the machine puts out to the pedal and what voltage range comes back from the pedal. then you can work out what pot resistance is needed.
tweak it until it breaks
Jack Ryan
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tweake wrote: ↑Sat Dec 20, 2025 8:15 pm i will have to see what voltage range it puts out.
typically the pots versions do the same thing, use the pot as a voltage divider and output a certain voltage range.
hopefully just a simple measure of what voltage the machine puts out to the pedal and what voltage range comes back from the pedal. then you can work out what pot resistance is needed.
There is no pot, it is a digital control. BOC couldn't tell me if the machine was also compatible with analogue (pot) control. There is no information in the welder manual and no information about the foot pedal.

Jack
tweake
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Jack Ryan wrote: ↑Sat Dec 20, 2025 11:45 pm
tweake wrote: ↑Sat Dec 20, 2025 8:15 pm i will have to see what voltage range it puts out.
typically the pots versions do the same thing, use the pot as a voltage divider and output a certain voltage range.
hopefully just a simple measure of what voltage the machine puts out to the pedal and what voltage range comes back from the pedal. then you can work out what pot resistance is needed.
There is no pot, it is a digital control. BOC couldn't tell me if the machine was also compatible with analogue (pot) control. There is no information in the welder manual and no information about the foot pedal.

Jack
they are not "digital" as such. there is no data. odds are its sending back voltage. pots often work the same way, as variable voltage divider, it sends back a voltage. the machine won't care if its a pots sending back voltage or hall effect sensor. as long as its the right voltage range.
it also has a board in there with a rectifier and a bunch of smoothing, so one side is probably sending out ac and its converting it to dc.
tweak it until it breaks
Jack Ryan
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tweake wrote: ↑Sun Dec 21, 2025 5:08 am they are not "digital" as such. there is no data. odds are its sending back voltage. pots often work the same way, as variable voltage divider, it sends back a voltage. the machine won't care if its a pots sending back voltage or hall effect sensor. as long as its the right voltage range.
it also has a board in there with a rectifier and a bunch of smoothing, so one side is probably sending out ac and its converting it to dc.
I'll have to have another look. Quite possibly I am wrong but I thought it was a coded position sensor.

Thanks for the heads up.

Jack
tweake
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Jack Ryan wrote: ↑Sun Dec 21, 2025 9:29 am
tweake wrote: ↑Sun Dec 21, 2025 5:08 am they are not "digital" as such. there is no data. odds are its sending back voltage. pots often work the same way, as variable voltage divider, it sends back a voltage. the machine won't care if its a pots sending back voltage or hall effect sensor. as long as its the right voltage range.
it also has a board in there with a rectifier and a bunch of smoothing, so one side is probably sending out ac and its converting it to dc.
I'll have to have another look. Quite possibly I am wrong but I thought it was a coded position sensor.

Thanks for the heads up.

Jack
an encoder would be extremely expensive. maybe someone has done it, but considering most pedals are use dirt cheap pots i kinda doubt it.
in this case its a throttle pedal off a forklift or truck. no one uses encoders on those (that i have seen). they are typically pots. a hall effect is kinda fancy for one of those.

if i have time over the holidays i'll test it and draw out the circuits.
tweak it until it breaks
Jack Ryan
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tweake wrote: ↑Sun Dec 21, 2025 11:35 pm an encoder would be extremely expensive. maybe someone has done it, but considering most pedals are use dirt cheap pots i kinda doubt it.
in this case its a throttle pedal off a forklift or truck. no one uses encoders on those (that i have seen). they are typically pots. a hall effect is kinda fancy for one of those.

if i have time over the holidays i'll test it and draw out the circuits.
That'd be great, thanks.

By the way, I found the NZ BOC pedal and it is not the same as the AU BOC pedal. That doesn't necessarily affect the conversation - it is still a pedal with a reused device inside it.

Regards
Jack
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