Warco Major CNC build log

**Robin Hewitt** · 26-06-2009

40t pulley just arrived. RS must be slacking, I ordered it at least 11 hrs 30 minutes ago :naughty:

Originally Posted by Kip

You must feel awful so I'll not mention that I intend using a pair of 30mm SC30UU linear bearings to prevent the trig equation needing to be worked out :D

Okay, curiosity aroused, what trig?

Robin

**BillTodd** · 26-06-2009

It could be pythagsrus not trig....

It's trig whether you use pythag or not ;)

BTW Was Michael Jackson's last hit called 'the floor'?

**John S** · 26-06-2009

Originally Posted by BillTodd

BTW Was Michael Jackson's last hit called 'the floor'?

Dunno but the O2 comeback tour is sure going to be special................

**Robin Hewitt** · 26-06-2009

Originally Posted by Kip

11.5 hours....useless!

Strangely true, when I looked in the box I found an empty 44t packet and a brand spaking new 40t. Nice to have a spare I suppose

Originally Posted by Kip

My thought on the swivelly bit at the bottom..if it twists it shortens the effective length of the ballscrew=bad?

I don't think it can twist without bending the screw, I didn't stint on the metal :nope:

I now have the 40t pulley and belt in place with a faux honking plate fudged out of a bit of 2" x 3/4" iron.

It feels good, any shift on the motor moves the handle, moving the handle spins the motor. I would have wired it up but when I looked for a bit of chocolate block connector all I could find was 80A

Time for some G-code to make the real honking plate

Robin

**Robin Hewitt** · 26-06-2009

Originally Posted by BillTodd

BTW Was Michael Jackson's last hit called 'the floor'?

I had heard he was a bit off colour but it was still a surprise.

**irving2008** · 26-06-2009

Originally Posted by Robin Hewitt

Strangely true, when I looked in the box I found an empty 44t packet and a brand spaking new 40t. Nice to have a spare I suppose

I don't think it can twist without bending the screw, I didn't stint on the metal :nope:

I now have the 40t pulley and belt in place with a faux honking plate fudged out of a bit of 2" x 3/4" iron.

It feels good, any shift on the motor moves the handle, moving the handle spins the motor. I would have wired it up but when I looked for a bit of chocolate block connector all I could find was 80A

Time for some G-code to make the real honking plate

Robin

Is 'honking plate' a real term or one you made up to describe a 'big lump o' metal'?

I am looking at the pics but still not seeing quite how the quill gets moved... and still moves the motor when you turn the quill handle...

**John S** · 26-06-2009

It's actually British Standard Honking Plate.

**Robin Hewitt** · 27-06-2009

Originally Posted by irving2008

I am looking at the pics but still not seeing quite how the quill gets moved... and still moves the motor when you turn the quill handle...

The frictional losses on a ball screw are low. The screw can turn the nut if you have the means to push hard enough.

Spin the motor by pulling on the handle and you can feel if something is binding. Should be smooth

**irving2008** · 27-06-2009

Originally Posted by Robin Hewitt

The frictional losses on a ball screw are low. The screw can turn the nut if you have the means to push hard enough.

Spin the motor by pulling on the handle and you can feel if something is binding. Should be smooth

Ah, what is the lead on the screw... I hadn't realised it was that big a lead. But what stops the quill dropping under its own weight then when the motor is powered off? Or is there sufficient stickiness in the cogging to stop that?

**Robin Hewitt** · 27-06-2009

It's 5mm lead, the 32:40 pulley reduction gives 4mm/motor rev

The quill return spring is there but it wouldn't drop under it's own weight anyway. You gottta pull to spin it.