Core Material - Magnetite

[888spo]

Hi all!

Anyone out there fiddle around with casting their own cores? Looking for some pointers on the process... Picked up some Fe304 locally and checking around on what is the preferred mix; Epoxy, Silicone? As the material cures any problems with the magnetite clumping in one area?

Can't seem to get a clear answer on any differences between black sand and magnetite, is there any?

D./

ps. Congrats on the new forum! nice to have a place where like minds can meet.

[Tom C]

No I have not, I try and stick with the welding rods. most people who have played with magnetite use epoxy as a binder. you definately want the iron in the core though.

Tom C

[alfinip2000]

Tom, as your observation so far, did you find any difference between R60 and other mild steel welding rod?to the efficiency?.. i found that, even r45 welding rod can do the job,yes in the first cycle it maybe not efficient (compare r60?)but in the end after the batt is conditioned (shorter time of charging) the less efficient r45 (if any) will be neglectable.. Ps:sorry for the english

[Tom C]

rg 40 rg 45 and rg 60 are all very close chemically, one has 5 percent more manganese or something. I spent a long time at the local welding shop looking at the differences. all 3 are interchangable as far as weld strength and ductile strength. they are so close as to be negligible. all are gas welding rod. I have used them all successfully. it depends upon what the shop has in stock at the time. currently I have RG 40 in a 5 LB tube I am using up. the rod is important as it keeps the magnetic fields from staying built up in the core. I am going to try soft iron wire rusted next.
Tom C

[alfinip2000]

Just additional info.. i use this as reference AWS A5.2-92 - Spec. for Carbon & Low Alloy Steel Rods for Ox .. page 13, hope it helps

[888spo]

Tom,

Came across a few videos on u-tube "magnetite cores" one fellow is using epoxy successfully. He does emphasize keeping the mixture as dense as possible, makes sense if you want to pack as much iron in there as possible, was mostly curious to see some the effects commented on, in regarding less heat and higher spikes due to Magnetite unique properties. Tks.