Spot Welder Settings?

[datsun280zman]

I`ve got a spot welder I`m trying to use for thin stainless sheet. (.020") Problem is, it`s way too powerful and there`s no adjustment. I`ve been looking at some way of toning down the power and was wondering if I can use a variable speed control device for controlling the input voltage. The welder is a 110v AC. Would this work?
The owners manual that came with it stated that for that gauge of steel the switch should have to be depressed for 2-4 seconds. I can`t hold the switch for more than 1/4 sec without blowing holes through both pieces!
Any help appreciated.

[Pilot Dane]

Do you know anything about how your welder works? Is it electronic or is it just a dumb transformer?

On the Miller website they recommend using longer tongs when welding thinner material to reduce the heat.

Also, do you know what type of stainless steel you are welding (what alloy)?

[nap]

I don't think I have ever seen a spot welder without some sort of adjustment.

post manufact and model. Maybe we can find something designed for it.