Would like to make a little h-bot plasma table
1. 2525mm belt, 505 teeth, 5mm pitch 25mm wide
2. nema 23's 3.1 in all 4 corners
3. 45mm box alloy
4. 20 or 25mm rails, double blocks
5. gives me a 450mm ish square work area
6. smooth stepper usb break out board
first question is, because I want motors in the 4 corners to resist the racking, I gather I will need drives for each motor, but can simply connect both motors and both drivers to the same output step and direction from the break out board?
second question is can sheet cam control the movement of a h-bot?
3rd question is would you like to hazard a guess as to the teeth count of the
gears I would need? as it is a right pickler, as the drive gears are available BUT
the smaller ones have a 6mm bore and the larger 'say' 30 ish teeth pulleys jump to a 8mm bore, I am aware that nema 23's come in 8mm shafts and the smaller 17's in 6mm or 6.35/1/8 what do you reckon for tooth count/diameter?
---------------------------------------------------
PLASMA CUTTER
I did buy a pt-31 scratch start machine torch, but now have bought a pilot arc head......
http://www.ebay.co.uk/itm/251467476174? ... 1439.l2649
so, if I am only intending to cut 5mm ms plate, and now know that the pilot arc torch need not scratch the surface to start, can I not simply control the peirce
height at what ever the 'correct' peirce height for that torch and 5mm ms is? be it for example be 10mm.. and the cut height at 2mm 'guess' I mean what happened before thc's came into being?
can I not set the rapids and peirce the same height
I would like 'as its such a tiny plasma machine' to simply have the torch go up and down on a cable from the side on simple levers so I can have the limit switches inside a the box with the motor, so IF the above is possible WOULD I need any more than 10mm of movement, or copuld I not even run the up and down cable from the likes of a throttle body variable resistor, take the parts from a car.
I would like to keep the closed loop belt at a set length 2525mm as for some strange reason I think its going to be easier to make the machine square, i.e. with all the teeth clocked north south east and west, plus macking replacement easier - maybe it is also so I don't go and build a larger table - I want it portable, also want it as low a profile as possible, think I want double y axis gantry and the torch inside,
anyeways what do you think please chime in, especially on the tooth count as I want to buy some bits......................
THANK YOU