Re: Lurker stepping forward
Quote:
Originally Posted by
Ninjabika
Hi all
Well I've been hanging around here on and off for a few years and have finall took the plunge and purchased a kit of new second hand parts off eBay.
A bit about me, for 26 years I was a multi skilled machinist, fitter, welder, mig, tig, mma, did also rats general purpose maintenance machine shop.
Unfortunately been out of the game for 10 years or so.
No more access to machines or kit, this would be so easy then lol, anyway I'll be making this machine mostly out of steel to start with, the gantry sides might be replaces with Ali ones once completed.
I intend driving the x axis via 2 nema 23s one on each side
Mechanically wise I feel confident in building a strong well engineered machine.
Electrically I think I'll need a lot of advice, not really my strong point, I'm sure I'll have lots of questions and hopefully some replies,
Now I've got to start sorting steel out ,
one immediate question which is recommended, to mount the motors direct via a flexible coupling or have them t5 belt driven to the ball screws ?
Here's a list of what I bought of eBay, I know I need a power supply, any suggestions ?
All of the parts are new second hand as never been used and were supplied originally by cnc4you
I will be building the machine around the dimensions of the parts, not too sure of its purpose yet but I will want to machine aluminium definitely.
Anyway here's the parts list
HGR20 20mm square rail 1500mm 2 pieces
HGR20 20mm square rail 1000mm 2 pieces
HGR20 20mm square rail 300mm 1 piece
HGR20 20mm square rail 296mm 1 piece
Hiwin HGH20 square carriage 12 pieces
RM1605-C7 Ballscrew with anti-backlash ballnut 1200mm (total length 1262mm inc shafts) 2 pieces
RM1605-C7 Ballscrew with anti-backlash ballnut 900mm (total length 962mm inc shafts) 1 piece
RM1605-C7 Ballscrew with anti-backlash ballnut 300mm (total length 362mm inc shafts) 1 piece
BF12 TMT ballscrew bearing and support 4 pieces
BK12 TMT ballscrew bearing and support 4 pieces
RM1605 ID 28mm ballscrew nut mount compression fit 1 piece
Spindle motor 2.2 KW water cooled ER20 with matching VFD inverter 1 piece
80mm spindle mount 1 piece
Water pump for spindle motor 1 piece
Stepper motor 4Nm Nema 23,4 pieces
CWD872 Digital stepper driver 7.2A 80VDC or 60VAC 4 pieces
UC100 USB motion controller 1 piece
KK01 breakout board 5 axis with relay 1 piece
Regards Martin
HI Ninjabika it sounds like a plan :-)
Please start a build log and put in lots of pictures.
Grtz Bert.
Verstuurd vanaf mijn SM-A320FL met Tapatalk
Re: Lurker stepping forward
Hi Martin,
Your parts list so far looks great. Should get a nice DIY machine from that list.
Building your own linear power supply is not to difficult, but you need to decide if you are OK with mains power projects. Here is Joe's video:
https://www.youtube.com/watch?v=4OoQQg76ar4
The other option is to buy a SMPS style power supply but when I last looked these were expensive and / or not so powerful, and like all SMPS will not soak up any back EMF from the steppers. Linear supplies will and this is often quoted as an advantage.
You can direct drive via coupling or belt drive, both will work. Belt drive is popular because you can tuck the motor out of the way instead of sticking out, and you can add ratios to switch the speed/torque if required. It can add a minor bit of smoothing to the torque delivery but I don't know if that is such a big issue these days with digital drives and resonance control. Some people have been concerned over belt stretch and accuracy but my own experience and many others on here is that for DIY machines it is no issue. On the subject of belts HTD5 profile is popular in 15 mm width. I wouldn't go with t5 style pulleys, HTD tooth profile is designed for high torque. Belt drive is my preferred method on the main axes.
