A good way to add a variable speed controller for my re-made Hobbies fretsaw.

Hi folks.
I have decided I want to add a variable speed foot controller to my re-made hobbies fretsaw.

https://www.instructables.com/id/1950s-Hobbies-treadle-fretsaw-remade/


My question is what do you guys out there think would be the easiest, least costly (cheap) way of doing it?
I have given some thought to using a foot controller from a sewing machine possibly because this thing started life as a treadle fret saw & I guess it seems fitting that it should follow a similar evolution as sewing machines did.
I know very little about sewing machines so if anyone has any ideas regarding this I would welcome them.
I plan to include an isolator switch on the machine itself, it seems a good idea as we have a small grandson who visits very often as well as two dogs & 'ible the kitten & as much as I try to keep them out of my tiny workshop it sometimes seems as if I am the only person in the house who has mastered the skill of closing the door so with all those feet around I want to be able to kill the power when I am not actually cutting.
So there you go guys what does the combined genius of the 'ibling world have to suggest for my little project?

Nostalgic Guy (author) 7 years ago
I see your point if that is the way you like to work then it would seem a bit pointless.
I am planning to do quite a lot of detailed work cutting aluminium & steel so I want to be able to stop the blade keeping both hands on the workpiece, the way things are at the moment this is not possible so as I am going to have to alter the machine anyway it seems sensible to set it up the way I am comfortable with it.
The scroll saw I used to use had a variable speed foot controller & I found it very useful particularly when working on very soft woods so if possible I would like to do the same with this one.
I guess it is really down to personal preference I just happen to prefer to have the option of a variable speed.
rickharris7 years ago
I have a variable speed scroll saw - hardly ever use it one anything but High so why bother. Press more gently - cut slower.