slappynuts

Ok so I am building a ac/dc tig machine because I am too broke to buy one. Right now I have the high frequency part finished and this could be used almost as is with a tig torch and stick welder. I may go that route if I can find a cheap one but I am facinated by what has been done with mircowave transformers

slappynuts

Ok so here is what I am working on now. The high frequency high voltage stage of the welder. There are some plans out there that work using car coils and I am doing something similar to that except I am using stuff from the local surplus store and some hardware store ----.

This is the set up that I am emulating but I am doing it a little simpler way.
http://www.casano.com/projects/hfstart/index.html

Here is the circuit I am using just because its simpler.
http://i279.photobucket.com/albums/k..._Gill_Coil.jpg

For the spark gap I think I am going to use a non resister plug from a lawnmower and instead of winding a ferrite core transformer for the last stage I am going to use some rolled up banding material.

I have the coil driver working now and should be able to get this all tested and confirmed working before the weekend for you guys.

b18.

RacingTiger

+5

t_cel_t

i physics we used these machines called spark timers, what we did was set it to like 60hz and then made it jump through paper and describe motion. but they would jump over an inch. there has to be someway of using one of those to start the arc and then somehow isolate it from the main welding circuit.

t_cel_t

actually this is the exact one we used
http://lh3.ggpht.com/_0NJn9fEA_vk/Ro...8/DSCN5135.JPG


here is one for cheap
http://www.basicsciencesupplies.com/...roduct_Count=7

b18.

I'm pretty sure that's what the High Frequency Start does, essentially.

Otherwise you have to get close enough to jump an arc at the current you're working with, scratch start.

Cool linkz.

slappynuts

Here is the basic high voltage generator for the arc start. Its a dimmer switch , a 4uf 660v capacitor and a bosch chinese knockoff coil.I got the coil ($11.79) and the dimmer switch ($2.79) from fleet farm and the cap was had from the local surplus store for $4.

slappynuts

If you are having trouble getting the cap there is a few of them here. I would probably go with a little more than 4uf though. The spark will jump 1 inch the way it is but a larger cap should give a little more jump.

To finish this part we need a sparkplug and need to wind a crude second transformer like in this link.I will be using wound up metal banding material instead of the ferrite core because its cheaper and easier to get.
http://www.casano.com/projects/hfstart/index.html