PDA

View Full Version : Desktop cnc mill



impact
04-26-2004, 08:34 PM
Hi, I am new to the boards and relitively new to cnc machining. I am a 16 year old, currently enrolled in a work expierience program at a local cnc shop. I would like to purchase a mini/desktop cnc machine for my self so I can machine parts for paintball markers and modify existing recievers. If you are not familiar most parts are made out of 6061 aluminum.

I plan to do familiar things to what this person does...

www.whitewolfairsmithing.com

He has a Taig cnc mill and loves it.

But I am wondering what would be a good mill for me thats relitively cheap? I have 1500$ but I think i could get more, if possible I would like to buy used.

lancedulak
06-18-2004, 02:28 AM
I'm suprised noone has responded to you on this.

You have plenty for a very nice desktop cnc mill if you do it yourself.

From harbor freight you can get a http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=44991 minimilll ($459 or http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=47158 micromill ($279)

The micro is good for parts say 6" x 6" x 6" (maybe slightly smaller or larger depending on other things). You could do larger parts with a lot of effort. The micro will handle bigger parts. The mini will sit on your desktop and be say 6" taller than your monitor is high and need about about 24"x24". The micro is a lot bigger and sturdier.. which has advantages and disadvantages.

I have a micro. No modifications to the base machine. You can use a Xylotext 3axis board to drive it. The current board is $120. The new board he's coming out with is $150. But i'd wait it sounds worthwhile. You'll need a power supply for the stepper motors. Price depends on the steppers mostly. $20 to $50. You'll need cabling to the steppers. I'd budget $20 for that. Various electronic components etc another $20 to $50 depending on how "nice" you want to make it. You can buy steppers on ebay for about $25 each. Maybe a little more or a tiny bit less. They need to be at LEAST 120 oz/in. Mine are 150 and positively FLY. Even the z axis (suprisingly). You can use Servos instead of steppers but your talking a quantum leap more in expense. You'll need something like Gecko drives ($100 per axis) plus servos (much more expensive than steppers). Servos are faster , etc etc and allow more control. Its up to you. I Love the xylotex myself.



You'll need a STURDY mill table of course. You can build one yourself or a GOOD desk would support a MICRO. If you want to use it indoors you'll need a cabinet. Build one yourself. Figure $20-$75 for the table/cabinet.

Your best off using a separate computer to control your mill. You either need a separate power supply or to use a 5v takeoff from your computer. Plus when your cutting youd be smart not to be running other apps (and you CANT if you use turbocnc). The good news is the second computer can have a cheap junk black and white monitor, no sound or almost anything else. Just a cpu, ram and an old tiny hard drive.

For whichever mill you buy you will need the cost of the mill again in tooling. But this you can buy over time. A BIG advantage of the Mini over the micro is that it uses r8 collets. Which are bigger and less expensive than the 2mt the micro uses. Things to get right off are collets or endmill holders, a vice (you can use a cheap drill vice to start), some endmills ($20 from hf), oil or wd 40, a caliper ($20 digital from hf. Nice one too).

For your 1500 you could have all that plus some, especially if you shop around. Just a word of warning. This is a time intensive project. Just waiting for all the parts to come in takes forever.

Good luck! and whatever way you decide to go i hope it works out :)

MIKENLN
06-29-2004, 01:35 AM
i would take a look at the homier mini mill a lot of bang for the buck. Already has R8 spindle and a good place to start. good luck mikenln

bgriggs
06-29-2004, 07:42 PM
I have posted some pictures of the Harbor freight mini mill. I just bought this one and took pictures as I unpacked. It is a nice little mill.

http://www.cnczone.com/gallery/showgallery.php?cat=500&ppuser=1709

Bill