Don't waste your time and money on 300 brushes, think about it, if Mr. Lincoln thought it would weld better with 300 brushes don't you think he would have put them in the begining when they were developing the machine. It all happens from the shoulder to the holder. Thru the years there is always some magic voo doo BS out there that hands get caught up in chasing that perfect weld. Oh Yea, leave the damn rack alone. Probably more good welding machines screwed up by rolling the rack, than any thing else.
Easy there, I would not want to put the wrong brushes in my machine in the first place. But a friend kept telling me about putting some 300 brushes in his, I figured I`d see what kind of response I`d get to this question. I didn`t think it sounded like a good idea but if he wants to put them in his machine, I figured I`d see what some other folks knew about it. Lord knows I was not born with a stinger in my hand but I`m getting better.
i have done it to my 83' Sa200. only on the neg. side. it softens up the arc. I like it and know alot of people that do it. it is like having a arc force knob on the machine
Does it do this because the 300`s have a larger surface coming in contact with the commutator? Also noticed the pigtails on them are a much thicker gauge of wire.my I have a `65 redface (5568 ) and had to break two sets of my brushes loose, granted this was awhile back . Anyway just wanted to know, always wanting to learn more about 200`s.
Brushes are formulated for certain characteristics and the most important is called current density. In other words amps per square inch. The current density has to be within a certain range to keep sparking or armature wear within reason.
the old style T344 brush is thicker, covering more segments on the armature--hence more heat pull and the need for a bigger pigtail.
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