[damae]

Warning -- lye is dangerous stuff. I put the juice glass inside a stainless steel pan, wore glasses and rubber gloves.

That's a cool trick. I have a water jet cleaning machine at work that uses NaOH as a cleaning solution -- one quart of powered NaOH to about 8 gallons of water. The instructions say that if you spill any on your shoes, you should "discard" your shoes immediately!

Of course, we don't throw our shoes away. But it made us think twice about touching it with our bare hands. I got some on my hand accidentally and it leaves the fingers feeling tingly, like you took a layer of skin off with sandpaper.

Also interesting to hear it's called Lye. We were told it's a chief ingredient in dishwasher soap. Anyway, good warning -- be careful!

[Cold Fusion]

That's a good piece of advice, thanks! Most of the time the bit ends up breaking because of the clogged flutes. If I am able to hit the Estop in time, the chips normally come out with a razor blade.

I've dealt with some pretty nasty chemicals before. Lye is like rainwater comparatively. We once did a test of 97% sulfuric acid on some fabric. It reduced a shop towel to a bubbling black pile of goo in about a second.

[itsme]

Hi there,

I would say that a concentrated solution of NaOH is just as bad as a concentrated solution of a 'strong' acid (HCL, H2SO4 etc). You need to be careful with any skin contact and particularly your eyes. I certainly wouldn't say it is like rainwater when compared to these acids - it is nasty stuff.

Regards
Warren

[Cold Fusion]

It's been a while since the last update, but unfortunately not a whole lot has been done. I've decided to change the Z axis motor to a Stepper (it's a long story). Hopefully this will work as good, or better then a Servo. I figure that driving almost a thousand pounds up and do is not a good idea over 20ipm. Figuring in gear reductions and ballscrew pitch, that brings the rpm needed to 400. That's just about the perfect range for a stepper, because after that the torque falls off quickly. Also, the Z axis won't be moving 99% of the time. Since simple holding torque is all that's needed, a Stepper seems the best way to go.

Yesterday I got the .001 indicator and worked on tramming the table. When I first took the measurements, it was tilted in both axis by almost 5 degrees. The indicator was mounted using an 8" swing bar, which I've heard is a sufficient length. After an hour I got the X and Y to about .0005. The instrument is only graduated in thousandths, but that needle didn't twitch through the entire sweep....

[rustyolddo]

Also interesting to hear it's called Lye. We were told it's a chief ingredient in dishwasher soap. Anyway, good warning -- be careful!

It is used in diluted concentration as a degreaser. Purple Lightning is a popular brand. Also, lye is used to strip the anodizing off of aluminum and also as a prep prior to anodizing/reanodizing.