I had some problems with stress cracks and I am reprinting everything in abs.

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(Rick Sollie) #1

I had some problems with stress cracks and I am reprinting everything in abs. Now that I have access to a printer that will print ABS again. I ran into the same problem Ashley did, removing the brass bushings. I dunked the whole thing in boiling water for 20 seconds and it was surprizingly easy to twist with plyers and get them out. I tested and they slide okay, but did I ruin the bushings? Did it exude the oils? I can’t tell just by looking at them.

(Igor Kolesnik) #2

You should be able to restore the lubricant in it. Just dump them in oil. I would try thick grease and put the container in the hot water. Just dry them first

(Eric Lien) #3

Be careful with heat. The inner section is epoxy potted into the outer housing. The epoxy is what forms the spherical joint. I learned the hard way once not to heat them with a torch to press them in. The epoxy all cracked and fell out.

(Igor Kolesnik) #4

Warm water should not damage the epoxy.

(Eric Lien) #5

But might deposit plastic residue on the inside bronze surface when boiled. So I think a light cleaning of the inside, and a re-oil job will do the trick.

(Rick Sollie) #6

Thanks guys! I thing I will try the heat gun on the next set.

(Eric Moy) #7

Be careful with a heat gun. Boiling water will only go to 100c whereas a heat gun gets much hotter. There are 2 stages to damage. If you reach the glass transition temperature, the epoxy will actually yield/bend permanently. If you heat it with a torch, you will probably break down the epoxy. It’s a thermoset, so you can’t really reflow it, it breaks down at high heat. Glass transition is just a weird relaxation/mobility of the bonds. Hope that helps

(Rick Sollie) #8

@Eric_Moy thanks for the information. I was jut on the way to the garage to look for it.