Member postings for Russell Eberhardt

Perhaps easier to find: "Lathework - A Complete Course" by Harold Hall.

Russell.

Have a look on here

Russell.

55 seconds to boot into LinuxCNC or 70 seconds to boot into WindowsXP/Mach3 and that's on an old second hand machine. If that's too long leave your PC in standby.

Don't connect the PC to the internet. If it works it never needs security updates so no checking for updates, no virus scanner needed as you won't get a virus, so very little overhead.

Russell.

.. and in "carroting" a process that removed fur from pelts before making it into felt.

Russell.

Inertial navigation systems are used on fighter aircraft and missiles they use acceleration sensors, integrating the acceleration to get velocity and integrating the velocity to get position. These systems respond quickly but need input from GPS to correct the position frequently.

It would only take a tiny error in the measurement and maths for the system to think it's moving when in fact it is not. A similar error will occur when moving at a constant velocity. The error would then accumulate over time. Even with frequent homing, the errors would be much too great.

A typical chip (ADXL362) has a resolution of 1 mg on the 2g scale. That's one part in 2000 and the error will be much more as the nonlinearity is up to 0.5%. Remember that's just the acceleration not the position.

Good luck if you're going to try it!

Russell.

Unfortunately they use acceleration sensors rather than distance sensors. In principle, if you could measure the acceleration vs. time accurately enough and performed a double integral you could get a measure of distance but in practice the errors would be enormous.

Russell.

I thought you had to put it in a bucket of urine and stamp on it for a few hours - not tried it myself

Russell.

Not good enough. For 25 nm resolution you would have to use an Extreme UV or X-ray interferometer

Russell.

A thread on my (S)X2 conversion is here if it's any help.

Russell.

12 mm. I still have all the bits I took off the SX2P mill when I converted it to CNC. They are in the "might come in useful some day" box.

Russell.

My Atlas lathe had rubber and felt wipers when purchased in the 1970s. The rubber wipers had degraded somewhat with the oil so I replaced them with a synthetic rubber (butyl rubber I think) and they are still in use. Perhaps it's time I made a new set!

Russell.

I strongly suspect that these felt pads won't last long with all the oil and crud. Did you see my earlier post?

Russell.

I just removed the spring assist on my X2 mill. I think it is only useful if you are using it as a bench drill. For milling it is superflous.

Russell.

Buy the real thing. Genuine oil seal felt in small quantities here: **LINK**

No connection but I've bought from them in the past.

Russell.

Yes, If you want to see the standard of work done by a female model engineer, have a look at the front cover of Model Engineer no.4366. (In digital editions).

Russell.

Agreed. Unfortunately "courtesy" seems to be a rather forgotten thing these days.

Russell - in grumpy old man mode.

Wasn't there a time when they used to pay for any letters they published? ... or was that another magazine?

Russell.

As a first welder I would go for an inverter one if you can afford it. Much easier to strike the arc and it won't damage your back lifting it!

Russell.

Yes, and the government surplus shops in Lisle street. Different sort of shops there now!

Russell.

Bonjour et bienvenu.

Russell (Dept. 66)