no worries yes im going to see if i can fit the gearbox in as it will be one less thing i will have to have made assuming they are good quality.
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no worries yes im going to see if i can fit the gearbox in as it will be one less thing i will have to have made assuming they are good quality.
sorry more questions
i am trying to find out what motor size i need for the x axis and to do so i obviously need to figure out what speeds i want to obtain from the machine.
From the research i have done i am aware that there is obviously a optimum speed for each material.
surfboard machines looks like they are cutting at around 10-12 inches per min or around 15,000 mm min which is obviously very fast i assume because foam is soft and the cutting path is very long.
for plywood which will be most probably the hardest thing i will be cutting it looks to be a third of that at around 5000 mm per min.
will this huge range be a problem?
i asume to get the high feed rate it will require a larger motor with more gearing?
from what i understand you have the cutting speed and the rapid speed which is what i under stand as the max speed it can travel when not cutting. is the rapid speed something you just find out when you get it up and running and see how fast it goes under no cutting load? or is it something that would effect choice on motors and gearing?
while i am not going to be in a mega rush to get things cut i dont waiting hours and hours and hours for it to cut a big surf board if posable.
best regards
Good idea and I've not seen any differance between the motors either so your good to go there.!Quote:
Originally Posted by charlieuk
Yes thats what I've done in the past and they are nice units Italian made I believe.? Just be aware thou the Nema34 motors don't spin as fast Nema 23 motors unless running High voltage drives(240V ac) so if your needing certain feeds rates for cutting your foam etc then be sure to select the correct ratio but other than that it's a good solution. Also be aware that the gearbox does make the overall motor/geabox length quite long so check you have room.Quote:
Originally Posted by charlieuk
Yes but it will be worth the trouble, don't look at the extra expense as costing more think of it in terms of saving money.? You'll only be spending one time not replacing and regreting.! . . . . To quote My Guru Ger21 . . "The cheapest way to get a good machine is to spend more money."Quote:
Originally Posted by charlieuk
ok so for the long x axis to get the fast speeds zapp have recommended the nema 34 8nm motor SY85STH118-6004B Nema 34 High Torque hybrid stepper motor
but said that the EM806 drivers would not be powerful enough so it would have to be the 2m2280n driver which looses the functions we have been discussing unfortunately. 2M2280N Digital microstepping driver
from a users point of view is it worth reducing the speed requirement just to run the other drivers?
while i want to build the machine to a good quality i just need to be careful the costs down spiral out of control.
If your going to run Nema34 motors then these are the drives you want. Kinco are good drives and while you won't have the abilty to tune out resonance they are still very good drives with advanced alogrithms for dealing with resonance and motor tuning so the chance of resonance being a problem is very very low. Also they provide a Fault output so you can use this to E-stop the system if you have stall just like the EM806.Quote:
Originally Posted by charlieuk
I wouldn't lower the spec to save money and these drives are 100% what you need with 8nm Nema34 if you want resonable speed from the motors. Also being 240Vac you won't need a power supply with these drives so you have to factor this into the mix. Obviously if your not using on all axis you'll need a PSU for the other axis.
Don't be tempted to try running smaller Nema23 motors with gearbox and heavy gantry running at high feeds because while the smaller motors may provide the speed and enough torque to move the gantry they will struggle to provide the torque needed to handle the slowing down and inertia of the gantry from higher feeds. The affect would be positional loss from steps being lost due to pushing affect.
Understand your point about keeping handle on the costs but The truth is that you can have high feeds but they do come at a cost. While 3.2 or 4Nm Nema23 motors run at 75V on the EM806 connected to correct gearboxs would work fine you would have to accept the fact they would be limited to what feeds/acceleration they can provide and the balance between working within an acceeptable motor tuning range and one that will cause miss steps etc will be a lot finer.
The High power Kinco drives and Nema 34 motors are the correct choice to deal with all the friction and inertia your going to encounter using R&P with gearboxs and heavy gantry and in the long run they will save you money by not needing replacing if you found the smaller setup just couldn't cut the mustard.
Unfortunatly if you want the best possible machine your just going to have to lube up Bite down hard and take it like a Man.!! .:dejection:
Cool that makes scene so will go with
nema 23 3nm for the y and z axis with the Em806 driver and the 8nm nema 34 with the 2M2280N driver
love the idea that the 2M2280N dont need a separate power supply as its going to be one less thing for me to worry about.
i dont suppose theres a driver that does the same for the other motors even if they were a little more, just thinking it would be one less wiring and things for me to learn wire and understand?
Just trying to sort out how i am going to do the x axis drive, i need to get about a 6 to 1 ratio. i was looking at the cnc router parts gearboxPRO Rack and Pinion Drive, Nema 34 | CNCRouterParts but they don't do it for mod1 rack is there anything similar available else were? Unfortunately i don't have any form of mill at the moment to make any parts so i am having to get most parts of the shelf.
Don't know of any that use 240Vac but I believe you can get versions of the Am882 and EM806 that will allow you to use AC voltage rather than DC so you can just use the correct size transformer without having to rectifie to DC and use smoothing Capacitors. That said building a DC toroidal power supply isn't difficult or rocket science.Quote:
Originally Posted by charlieuk
just to give you more of a idea on what i am planing to use the machine for
here is a hand shaped board hopefully the machine will do this hole process for me and give me much higher accuracy and control over the shapes
I have a helped someone in the past who lives near me with noise issues who shapes foam moulds for custom car body panels with a much simpler setup that what you have planned. See is video below of what he makes and the machine it's done on. (Which by the way I've had nothing to do with making the rough arse thing. . .lol)Quote:
Originally Posted by charlieuk
https://www.youtube.com/watch?v=cv-FrT0fA-c
https://www.youtube.com/watch?v=Vw1KXIgT96s
Thanks for those vids i had not seen them before if i can get that sort or accuracy on foam i will be more than happy i gess it comes down to the wood were the extra money spent will be noticed. I am hopping one day to make some moulds for boards and other things as well if it does turn out to be fairly accurate.