MadModder

That runs really well 

They are fascinating engines. They actually work using a phase change between the fourth state of matter , called plasma,  and  a gas .

The flame (or at least the blue part) is so hot the molecules are ripped apart in to charged ions in a very low density plasma. When they cool , they rapidly condense into a hot gas that is relatively much denser causing a partial vacuum. 

The plasma cools entirely through radiation, so polishing the inside of the bore will make a few more photon to bounce back into the plasma and keep it hot . That'll allow a bit more of the good stuff into the cylinder before the valve closes. 

Also it's important that the hot gas can escape the cylinder as the piston comes up . The vavle should spring open to allow this.

Well the Bosch Colt router bearings finally arrived after 14 days. I thought the order had gone astray from eReplacementParts dot com. Gee, whadya expect for $12 shipping for 2 small bearings that fit in a small envelope? Bearings were $12 so the shipping cost doubled the price.

Next time I'll order the bearings elsewhere, now that I know what they are. One is a 6002rs, the other a 627zz. Both common and like $10 per 10, and 2 day free shipping from the big river company. The ones received were made in Maylasia, so not exactly Timkens. Even Timkens are $5 ea. Oh well! 

  [ You are not allowed to view attachments ]  

  [ You are not allowed to view attachments ]  

It’s coming along nicely

This afternoon I reverted to my original SMCC card (the servo subsystem card that drives the turret via Siemens power amplifiers)

Initially the turret would unlock by driving the tool disk forwards, but when rotated wouldn't re-lock when driven back due to angular error. Driving it to the correct position by manipulating the lock / unlock solenoids and physically turning it, it then would settle back and I was able to select tools by program.

I get the impression that the positioning is not spot on as the re-coupling of the curvic coupling is a bit hesitant. I came to the conclusion then that the output stage of the SMCC controller had a small error offset due to a hardware issue.

OK this where I was a couple of years back before shingles destroyed my brain. I have sourced another SMCC card that was in another Beaver TC20 lathe but that one was controlled by a Fanuc PLC. Reading it's internal program  it is virtually the same as my one only differing in a couple of lines but these are to do with addressing the card so probably crucial.

My attempts at programming these cards in the past have drawn a blank - more research needed.

Thanks Steve - yes I'm a bit more able to get my head arround things now thank goodness.

This morning I went through all the digital outputs and proved that they were in the same state that the 'Q' words in the control were at - they were ! I suspect that the digital input output system is actually fine though it's not conclusive on the outputs as I can only observe rather than drive them.

However I HAVE found that the drive circuit for the main spindle drive is reporting an error - it also has a tell tale red LED that should be 'on' but it isn't. Fortunately I do have a spare so I'll install it when time permits - ATM waiting to meet and greet two sets of cottage guests whose arrival is imminent. (sounds of thumbs twiddling!)