Original poster: "resonance" <resonance@xxxxxxxxxxxx>We use 1 1/2 x 1/2 brass as the feedthru and then tungsten-molydenum threaded inserts in each end. I prefer the 1/2 size to dissipate the tremendous heat from the 2,500 Amp peak primary currents. We run at 3450 rpm on all our RSGs with 18 inch dia. rotors on the 10 plus kVA coils and 14 inch rotors on the 7.5 kVA coil.
Our G-10 rotor is 1/2 dia. and uses .000750" on the ream undersize. Dr. Resonance
I dont remember who it was that did a FEA on a G-10 disc but it was full of info ( if you can read the scales and color codes ;) )question #1. why 1/2 " tungsten? ( Im using 3/16 dia with no problems on the BIGPIG coil)400 bps roughly = 37 rps = 2200 rpm with electrodes centers set at 5.25" radius = approx 105 mphI would go for a minimum of 1/2" of disc ( from outer edge to electrode) thats alot of mass that will be wanting to be free. Dont know about the press fit idea ( it probably works quite well) and as far as set screws... Id choose 10-24 thread keeps the hole diameter small but useful.Dr. Res most likely has built something the same size you are looking at... maybe he can give some input.Scot D Tesla list wrote:Original poster: "Jim Mora" <jmora@xxxxxxxxxxx> Hello All,I have a 18"x 18" x 5/8" of G10 I took to my machinist who can make about anything. I could use some feed back on machining techniques to pass on. My first one was (12" x1/2") I made myself. Cutting this is the first. This one is much more massive and will have 1/2 " tungsten x 2.3 (12) pressed in. The feedback I got earlier was to make the holes .001 smaller and press the tapered tungsten in. How far from the edge would be wise? The set screw method directly into the G10 will hold them in place (I hope).This will be on a variable asrg gap maybe up to 400 bps or > than or so. Thanks, Jim Mora