What does "quenching with paraffin" do for the bolt?
73
Gary K4FMX
Shannon Boal wrote:
> Uh, Dick
> Maybe too late, but when you're in a hole, stop digging!
> OK, having said that, are the EZ outs broken off in there? When you get
> it apart, you might want to take it to a machine shop for thread repair.
> Automotive machine shops do a lot of this. Some of the machinists are
> amazingly good at it. They may not let you know how they did it, though!
> Please note, that I am an auto mechanic, not a rotor doctor. The bolts,
> EZ outs shouldn't keep you from seperating the housings. First, make sure
> that all fasteners are out, no hidden bolts? I would heat one housing
> locally near the parting area, tap with a wooden mallet/ plastic hammer. The
> aluminum should be heated carefully. A temperature guage can be a pine
> stick, which will char when touched to a 475 F surface. No hotter than this!
> To protect the gears, consider submerging the bottom in water, or wet rags.
> If you heat it in an oven, 325F should be plenty hot, and the ladies don't
> like it if we stink up the house....
> More on the broken bolts... in the future, the bolt can be torch heated
> on the head to a blue heat, maybe hotter, (but not to soften the aluminum
> near it), and quenched with parrafin, like a candle stub. It will come right
> out, easily. Having broken ones, do not try to drill or use EZ out. The
> drill will want to drift into the softer aluminum, and a broken EZ out is
> harder than a drill bit, so it will eat your drill bits! If a nut can be arc
> welded to the end, fine, quench with candle and remove, easily. If not, I
> would use a drill guide to keep the drill from wandering into the soft
> aluminum. This would be a steel plate 5/16" or thicker with a hole smaller
> than the bolt, clamped in place, or secured by an adjacent bolt. This will
> solve the drifting problem. I use carbide tipped drills for broken EZ outs,
> drill bits, etc. I customize my own drill bits for this...
> Dick, I wish you well!
> I've been in similar situations
> Shannon Boal K4GLM
> PS soaking a corroded assembly to loosen can be aided by acids. With iron
> parts, Coke(really!) is amazing. Vinegar maybe, for aluminum, I have not
> done this.
> I have used battery acid to soak apart iron parts, I would not try it for
> aluminum stuff.
> IF you soak in etching, use weak solution, and submerge the whole thing!!
> The area near the surface will be damaged!! Neutralize with dip in baking
> soda solution, spray with corrosion inhibiter.
>
> Hi,
>
> I'm trying to refurbish a very old Ham-M rotor. The previous owner
> managed to remove one of the 4 bolts holding the housing halves together
> and torqued the heads off two others. I managed to torque the head off
> the remaining bolt. It seems like the two halves of the housing should
> come apart now but I've been bathing it with WD-40 for a couple weeks
> and banging on the housing with a hammer, but can't get the two halves
> to separate. They must be really corroded together.
>
> I've also managed to break a couple of screw extractors trying the get
> the headless bolts out.
>
> Any suggestions?
>
> Thanks,
>
> Dick
> K7RB
>
>
>
>
>
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
> questions and ask for Sherman, W2FLA.
>
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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