another part for the shaper

[dallen]

Mayhem thanks for the compliment on the part, the porosity isn't as bad once I got a decent finish on the face.


now to make a big hand nut like was on it back a 100 years ago to replace the 3/8 bolt in the rod eye directly below the nut I just made, so I don't have to go find a 9/16 inch wrench to adjust the table travel.

looks like this, anyway its suppose to look like the photo, have to see how good my woodworking skill have improved overnight.

[oldgoaly]

DA,
you can add a little flux during the melt or degas after it is melted. With the Johnson pot furnace I do not degas, but do flux. when I used the crucible furnace always had to degas. So what that experience is telling me it maybe the way it is fired, crucible faster, more heat, more degassing needed? One other thing I do is when I get a good puddle of molten aluminum, I add an extrusion and stir it in, sure looks like the crud floats nicely at the top, that may help the gas escape? As always make sure there is no moisture in any of your scrap! It only takes a very small drop to blow a pot of aluminum, super heated steam is a powerful thing!
I'm sure you have seen this place http://www.budgetcastingsupply.com/Alumi...ts-601.php
Wish you were closer, we could have some fun!

[dallen]

Goaly, I use flux and a degassing component, normally I don't have as much of a gas problem as the photo shows. With your pot furnace you will have a lot less hydrogen absorbed into the melt that if you use a direct flame like I do, pot furnace would be nice to have if I did enough casting to warrant one but I don't really do all that much, I like doing it and wish that I had a reason to do more but my pattern making skills need a lot of improvement specially in the woodworking tool department.

what your saying about degassing when melting in a crucible furnace is true because Propane is loaded with H2O, high humidity on a casting day can cause problems in a melt.