New build with recycled parts on a ridiculous budget 120cm*60cm work area

[Nickhofen]

As Robert said ,down cut bit, slower feed and............ put self adhesive tape at the side you cut, after the cut remove it and you will have a cleaner cut.

[Desertboy]

As Robert said ,down cut bit, slower feed and............ put self adhesive tape at the side you cut, after the cut remove it and you will have a cleaner cut.

Good advice this was very old oak I tried a newer bit today didn't tear the same but still not perfect.

Just bit the bullet and bought a hardware step generator a Mesa 5i25 as my pc's not giving me the performance I can get out the machine.

https://www.ebay.co.uk/itm/272930377353

Plugs into the breakout board so no need to rewire which is good ;) I was in Vilnius last year I could have collected it lol.

This will generate more pulses than I could ever need it expands the BOB connectivity considerably but it's the pulses I can about, it can be linked to encoders for other funky stuff.

[Clive S]

Plugs into the breakout board so no need to rewire which is good ;)

What do you mean by this? This will plug into your PC PCI slot but then you will need a bob like a 7i76 if you just use a standard BOB you will still only have 5 inputs and the opto's will no doubt be slow.

[Desertboy]

What do you mean by this? This will plug into your PC PCI slot but then you will need a bob like a 7i76 if you just use a standard BOB you will still only have 5 inputs and the opto's will no doubt be slow.

https://forum.linuxcnc.org/38-genera...nerator#106403

Just remember most cheap parallel port breakout boards are not designed to be able to handle the speed potential of hardware step generation. They often have relatively slow optos, not a problem with a slow parallel port, and shouldn't be with an ordinary step motor config (unless your using really high micro stepping and spinning fast). But it can be a problem with high resolution step/dir servos.

So we shall see I guess I'm only using 8 (maybe 16) microsteps with nema's. Not worried about the other inputs at moment but at some point I will get a daughter board for it and if I find speed is an issue that will be sooner than later lol. I assume I can set the khz within a certain range for each axis? If I can run at 50khz per axis I'll be more than happy for now.

Am I doing my maths correct?
8*200 steps *20 (revolutions in 1m) * 2 pulses per step=64000 pulses/metre
I want 10/min it would be 64000*10=640000khz then divide by 60 == 10666.66 khz per axis

Good thing about mesa is their upgradability.

[JAZZCNC]

Am I doing my maths correct?
8*200 steps *20 (revolutions in 1m) * 2 pulses per step=64000 pulses/metre
I want 10/min it would be 64000*10=640000khz then divide by 60 == 10666.66 khz per axis

20 revs = 50mm pitch surely not.??

Khz = (steps per unit * velocity in units per minute) / 60

So Break it down into mm units not meters. So lets work on 10mm pitch with 1600 micro steps.

1600/10=160 steps per mm

160 x 10,000 mm/min= 1600000 /60 = 26.666Khz

[Desertboy]

20 revs = 50mm pitch surely not.??

Khz = (steps per unit * velocity in units per minute) / 60

So Break it down into mm units not meters. So lets work on 10mm pitch with 1600 micro steps.

1600/10=160 steps per mm

160 x 10,000 mm/min= 1600000 /60 = 26.666Khz

LOL that's why I need to check it was having a blonde moment ;)

[JAZZCNC]

[Clive S]

This will generate more pulses than I could ever need it expands the BOB connectivity considerably but it's the pulses I can about, it can be linked to encoders for other funky stuff.

I do read all your post on the other forum as well. But you will need more inputs if you are using encoders and dual homing etc. The beauty of the 7i76 is that you will have differentials output for the step gens and 24v inputs etc.