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Ah.. irving2008, iv read a thousand and one of your posts,, you always seem to go above and beyond the call of duty... mucho respect xx
the large motor is 1700W at 37v and the smaller one is 700w at 22v
im not to bad an engineer but the electic stuff is a bit rocket science to me
i have thought about going all the way around with the gantry but i do like the simplicity of it at the moment
Well 1700W input is 850W+ output, ~1HP theoretically you have the power to take around a 5mm deep cut with a 8mm 2 flute cutter at a feed rate of 500mm/min... but in reality your rigidity probably won't be up to that... but I reckon 0.5mm cuts would be possible, maybe a little more with a brand new very sharp cutter...
thanks for the compliments
PS.ive taken the liberty of adding spaces to your post so its easier to read.....:naughty:Quote:
Personally I don't like the motors showing on the sides of a CNC,so I've taken_ the liberty of relocating it
George (what are we going to do with you?:heehee:) CNC machines are not Art and don't have to be pretty just functional. Direct mounting a motor is the best solution as far as backlash and accuracy are concerned, all the professional machines Ive seen use this setup.
Its is only worth while using belt drive if you need to change the gearing.
Damm right, get it working first. If your milling Ali have you looked at the coolant side? Pumps, catch tray etc...After a few uses you wont care what it looks like only be amazed at the pieces you make with it.Quote:
i can always make it look posh when iv got the ability to machine:naughty:
nice one irving ! it sounds possible then
most of the work done on it will be in acetal delrin type plastics but i do need the odd ally bits and bobs
them motors nice and quiet!! :smile:
iv been collecting surgial tube at work to make a peristaltic pump with,
they have a low flow rate but must be worth a try for a giggle
they look pretty simple to make
i am sort of worried about coolant though... i wanted to put all my electrics under the base
Hi Mark,
Those brushless motors look like the type I use in my model aircraft. I was wondering how you are controlling them, and what power source you are going to use. Looking at your stats for the big motor:
2800rpm for 12v is a 233Kv motor. This will obviously give you 8633rpm at 37v no load.
1700W is achieved at 45A for 37v. Do you have a 37v supply, and more to the point, can it give out 45A at the same time? The 12v 60A supply we have at work is the size of a suitcase, and probably cost us a bit, so I'm interested in the bench supply you have in mind. If you have simply read the motor spec, then you might like to know that on aircraft, when run from Lipo cells (37v) these motors run at about 45A on average (depending upon prop and throttle), and last for 8 - 9 minutes before a recharge is required. If your bench supply can't give this kind of current, then your actual power will be down (plus not so efficient), and you may have to back off on the ali cuts. But then maybe you have a cunning plan for all this . . .
I assume you are using a speed controller to run the brushless from. What amp rating are you running on that, and are you using a servo simulator to control the speed on a dial?
If you can get this all to work, then you're right about the noise, very quiet. I did consider this route myself, but the above put me off. Keen to see more . . .
Hi Mark.Quote:
Originally Posted by blackburn mark
You can get peristaltic pumps on the 'bay reasonably cheaply. Do a search for 'condensate pump' or 'Aspen peristaltic'. I got one a couple of years ago for a tenner. For the last week it's been pumping dilute citric through a crudded-up coffee machine heat exchanger.*
Sorry, rambling again. Where did I put the Jaffa cakes?
John
*another ebay win.
5 of those cheap 50v supplies from ebay in parallel will give 43v-56v @ 50A for £12 each, not bad for £60...
lol Irving,how much will the electricky bill be?
im using a servo tester with an 80A speed controller
i bought the motor as a 250kv at 2000w but a review i read has it at more like 1700w
i have two server power supplies at 12v 45A each... im hoping to stick with 12v to keep
the speed down for ally
i can use the smaller motor at 12v for up to 10000rpm
im also hoping to replace a 3.17mm shaft in a 4000kv helli motor with a 3.18mm shafted
engraving bit... not sure how practical this will be as ill have to strip the motor every time the bit wears out... worth a try if im desprate to do some really fine work
this one should run up to 48000rpm on 12v (i think) it will be interesting to see
how the bearings hold up
feel free to critiqe... im sure youll know more about these rc motors than i do