Modding my budget Clarke Scroller - Part Deux

[twodoctors]

I did mentioned a foot pedal mod...

It arrived this morning. Found time to install it tonight. And it worked.

Here are a bit more detail for those technical (and crazy!) enough to try this mod.

Ultimately the foot pedal is an on-off switch. The saw already has a NVR switch, so the foot switch must come between the NVR switch and the motor. If you don't understand how NVR works then this mod may not be for you (we are dealing with main electricity after all). If you have the speed controller mod as well then it doesn't really matter whether the foot switch sits before or after the speed controller, as long as it's after the NVR switch.

The foot switch I used is this:

http://www.ebay.co.uk/itm/232029887103? ... EBIDX%3AIT

£9.79 from the bay. There is a cheaper one but that's plastic. These are also available from Amazon but a bit more expensive. Plenty of reviews on Amazon as well, as you will read the one-star review where they complain about no instruction included or people keep short circuiting the whole thing... Again it's not rocket science but if you don't know what you are doing then please don't do any mod where electricity is involved. The switch is single pole double throw, and the terminals are labelled as "Com", "NC" or normally closed, and "NO" or normally open. You only need to switch one side of the circuit. Those who knows what they are doing will know what I mean. I'll leave it at that.

The foot switch is good. The only negative is that it's a on-off switch rather than variable speed one. Now I have never used a Hegner or one with foot switch so I don't know if one that has variable speed control on foot pedal exist. Anyway it works. I haven't scroll anything using it yet, but hopefully it will give me a bit more control and encourage me to stop when in doubt about where I am.

Happy to answer questions.

Adrian

 

[martinka]

I've got two of those foot switches. Mine came from Amazon but the same seller sells on ebay. The first one I bought had a faulty microswitch and the seller just sent a complete new footswitch and told me to keep the old one, so I fitted a microswitch that I had in stock. Two for the price of one. I have a Hegner one as well and it doesn't have variable control.

 

[Claymore]

.......

 

[donwatson]

Thanks for the advice here Adrian. This is something I would consider.
One question springs to mind 'does this mean anytime you step on the pedal the machine will start up ?' , unless switched off at the wall socket.

take care
Don W

 

[twodoctors]

If you connect it all up correctly, then you will have to switch on the via the NVR switch (aka "green button"), then press on the pedal to activate. Switching off a the wall obviously switches everything off, and you'll have to press the green button to start everything again. Hope that make sense.

Adrian

 

[donwatson]

Thanks for the quick reply. My worry is that having switched it on via the green button then the foot pedal is in control of the machine.
I was thinking that when demonstrating, and having 3 or 4 eager pupils milling around, the pedal will need to be bolted to the saw stand with a safety cover over it only accessible from the front "just in case" ??
Don

 

[twodoctors]

That's the whole point. You control with the foot pedal... Quicker to turn the saw on and off, so more incentive to stop and see how things are going.

There are pedals with cover over it..thye are nearer £20 I think. In any case how safe the machine is down to the new users (and whoever is supervising them). There's no cure for stupidity (as the saying goes). :-D

Adrian

 

[graduate_owner]

You mentioned variable speed foot switches - do they exist? Well they exist on just about every electric sewing machine. Would this be a suitable starting point for you? I'm thinking you could get one ( often used entire machines are very cheap) and dismantle / upgrade the device. Might be worth investigating.

K

 

[twodoctors]

I'm sure someone sells variable speed foot switch but I haven't looked or spotted one on the bay.

The issue (even with the speed controller I have) is that the resistor in it is too high. ie the scroll saw only works on about a 1/4 of the turn, anything beyond the resistance is too high and the motor doesn't function. The same issue will crop up with the variable speed foot switch and it will be quite annoying to use (as you will have to press quite a lot for it to work and because of that it's difficult to control).

If anything the next mod would be to change the resistorto something more appropriate so I can more control. Not going to though as it will involve removing solder from a commercial electronic, and they are usually covered in flux of some sort, making it quite tricky to unsolder. (I also used to do lots of electronics when I was a boy so soldering is not a problem for me).

Adrian