2+2+3 More Plasma builds, double the joy ! 3X2M and 2.5X1.5M cnc plasma build.

More snow, everything is shut down, police told me twice today to go home !
All looks like a bad movie, and it got from +23 to -4 degrees C in an evening so messed up my ability to withstand cold, so i can not work much. That is not good. Living with chronic sinusitis since i was 17, so am trying to avoid headaches as much as possible, running up and down the stairs, doing pushups, eating popcorn, etc.
And it was such a nice a warm winter !
Will try to get something done tomorrow, if at all possible.
Regards, and stay safe.

Finally got some small ALU parts to continue working on this.
Today i made two belt reductions for the smaller of the two machines, one on each side, so here are some pictures, and a video of it moving.
Warning : No jokes about the machine laying on it's back, it is upside down, with feet's up and everything.
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Almost finished assembly of the reduction, will add a proximity sensor and tidy up the wiring. The white belt is 15mm wide and there will be one on each side, so way more than is needed for moving 30 to 40 KG around.

And here is the reduction from above, 1:3, GT2 belt.

And here is a video of it moving at 15meters per minute with some cheap drives. Tomorrow i might get the big Lam Technologie drives to see if i can bend something! The gantry is there just to keep the linear bearing from moving sideways.

Stay tuned.....

Built another two of the reductions for the big machine ( big = 3X2M cut area, small = 2.5X1.5M cut area ), so i took some pictures.
L shaped alu profile 90X50mm, 8mm thick, 200mm long, 2 pieces, holes drilled for the shaft and bearing screws:

Two bearing with holder and two screws/nuts for each side:

GT2 60 teeth for the motor side, motor pulley is already on the motor, and T3 15 tooth pulley for the driving side, for 15mm wide belt.

Two Nema 23 stepper motors, used ones till they are mounted on the machine, then new ones double length:

Two 8mm shafts, both sides have two ground parts to prevent slipping:

Finished gearing with the proximity sensor installed:

Another picture of the working side, missing an added 10mm thick 50X10mm alu part with idler bearings installed, out of bearings, so will do more pictures when i get to that:

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On the small one i also installed the wide belt on the other side and sensors, will have to do some more cabling and sort the homing and limits for both sides tomorrow, see if i can pull that with just two sensors.
Regards,
Tom

less is more with these machines i believe. lighter the better and you have it down to a science Tom. i had to watch the video twice just to figure out how you were driving the gantry not only is it done to be light and just enough to do what it needs to but very cost effective in design. your a smart cookie

machinedude wrote: less is more with these machines i believe. lighter the better and you have it down to a science Tom. i had to watch the video twice just to figure out how you were driving the gantry not only is it done to be light and just enough to do what it needs to but very cost effective in design. your a smart cookie

Yes it is when it comes to plasma cutting, the lighter the gantry/ head assembly, more acceleration = sharper corner without slowing down.
And cost effective is a must here, labour got to be cheaper than in China, and knowledge is worth nothing here. Pretty much same as US !

to put things into perspective the gantry on the machine i am building is close to 300 lbs steppers work ok but not in the sense of the acceleration needed on the long axis moving the entire gantry. no good for plasma. the other two would be good but not as good as a gantry sized like yours. servo's might do it with adaptive tuning and electronic gearing but at a very steep cost curve to get there. i might be further ahead to do a smaller dedicated table to be honest. light and cheap in design to make up for added cost in electronic and plasma cutter.

don't get me wrong i like what i have built i see it doing well at milling and can add a wood router with no problems. in that respect i kept it realistic on the spindle and spent more on the frame work end of it. with any kind of milling you run out of rigidity before you max the spindle load out and if you want to have any chance of milling mild steel you better have the right speeds to run the tooling at and a frame that does something to negate vibrations steel and aluminum extrusion is not enough.