The porous Norton wheel I bought from McMaster for $45, after buying a CGW porous wheel on eBay where the seller sent a nonporous wheel.looks like a job well done.
The 46H porous wheel might become your down grinding wheel or saver for chuck grinding.
Perhaps let the guys here know where you got the wheel and its cost.
How hot are we talking about to cause deformation?
I started grinding and it seems to be going okay. It will take a while. I have no experience but it seems reasonable. 0.001” depth, .020” stepover, 46 H Porous wheel.
The spark trail spreads across the wheel by the end of two passes, so I re-dress then.
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Third edit: using more coolant definitely helps. Fewer sparks and just seems better. I have a hand spray bottle I’ve been using to supplement the mister.
hey michigan , have you ever herd of using a copper chill plate or an aluminum heat sink between passes on a big part or chuck? a little water makes a pretty good transfer medium and can be wiped off for dry grinding to resume.rQt Op" (I think I was scared after that)
Likely the biggest and toughest SG job to do.
Good that you got scared. With a little heat and you may keep grinding to have a nice looking job and then find that when it cools it is .002 low at the center.
or have a sudden heat swell that sucks up into the wheel to causes a burn/warp. Mostly the burn causes a rapid expansion, and then a contraction, the contraction is the effect that warps the chuck.
Grinding a chuck dry you watch the sparks to know the space between them. when the sparks get closer together the next pass will likely sound different and you see and hear the grind not sound she same all the way across. You know you are in deep trouble. Some shop don't allow coolant on surface grinders. The worst chuck I ground dry had about .015 hollow/low at bump rail center. Don't ask me how they used it.
A weak mix of soluble oil make a very good chuck grind coolant, but you need really shake out your wheel after use
Yep, I posted a picture of my flood coolant Monday afternoon. It made a huge difference.Flood coolant helps a lot with that because it keeps the temperature constant. The coolant mist that you are using isn't enough to keep the chuck from warming up. Is there a way to rig up a steady stream of coolant?
haha! ill try beer next time, the evaporating alcohol may help with cooling, but I would only use coors light... anything else would be a waste...Q; (Is there a way to rig up a steady stream of coolant?) If you have no other then way hang a five gallon bucket with a 1/4" hose and gravity feed coolant. Use a calculator to convert that to metric if needed, something times something is the formula for converting, but close in close enough.
*Do test this/your gravity coolant device to know how much time it will allow.
Water, water with catalog coolant, un mixed coolant if according to instructions, water with some hack or homemade something, a coolant other than water or whatever coolant is used on the machine should do a fair job of it.. time and talent are just as important because one can still burn a wet chuck..
likely beer would work well, but if you are drunk enough to try beer you are in no condition to grind a chuck.
One time with not having a decent wheel I cut slashes to the OD of a wrong wheel by hand gashing the wheel on an abrasive cut off (parting) wheel, it workie just fine(wet).
Nice.I used my freshly ground chuck to clean up the sides of a cheap cast-iron v-block. It came out with 0.0001” parallelism over the ~3x5” surface. I am happy, as it’s the first thing I’ve surface ground besides a block of steel and the chuck.