Help with drill-Mill conversion

[HiltonSteve]

I seem to only be able to learn when I've tried it and F**ked it up for myself:heehee:

Best way of learning.....!

If I made a list of all the things that I have fucked up I would need a lot of paper, 2 catogories, minor and major f**k ups. I am pleased to say that as you get older you don't add as many things to the list.

My best major f**k up was ripping the cross slide clean off my newish CNC lathe because I did not set the chuck pressure high enough, the part came out of the jaws when I was screw cutting and got jammed between the chuck jaws and the toolholder at about 1000rpm. I was standing right next to it when it happened and I can tell you it went with a bit of a bang, had to add a new pair of pants to the repair bill!

Repair cost - £8,000 - thank god for insurance!

[Robin Hewitt]

I am pleased to say that as you get older you don't add as many things to the list.

That's something to look forward to then :heehee:

[Ross77]

Nice to know Im not the only one then

readjusted the antibacklash nut alignment and its much better now, so it seems perseverance is key. Spent ages the other nite trying to work out why it was binding, next day I spotted the problem in 5 mins.

Thanks again for all the advice. Its ok reading from a book or off the net, but being able to ask specific questions when you get stuck is brilliant. Definetly wouldnt have got this far on my own.......

[Ross77]

Had to put this on hold for a while and then when I got started again last week I crushed my finger whilst honing the ways.........

So decided to move on to the electrical side and sort out the stepper controller, after hours of trying to bypass the optos and feed the chips direct the L6203's (H bridge) decided to put on an impressive firework display.... @ 40V these things sure go bang.:whistling:

So all in all things arnt going to well.

Any body make curcuit boards for L297 + 2x L6203's with diode protection so I can transfer the remaining parts over to a less complicated board?

After a lot of serching on the web I think I've found out why I couldnt get it to work, There is an enable pin on the L297 that has to logic high! Am I right in thinking that will stop the chip from working?

Ive got another board to try, but not to keen to fry that one as well

[Ross77]

I have 2 dead boards and 2 good ones....all to go in the bin and good riddance to the worst £700 I ever spent.

You dont rate these as drivers then? Your not throwing away the good ones are you. :whistling:

Just want to get this thing running. Nearly finnished the x-y axis
Just the spindle, motor and z axisto do....

[irving2008]

@ 40V these things sure go bang.

They go bang because of excessive current not voltage...usually if upper and lower devices in the bridge are 'on' simultaneously... 40v across .5 ohms = 80A peak, 3200W instantaneously.... your PSU will do that for a few 100uS no problem!