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rebuildit
03-12-2005, 06:10 PM
Hello all,
I have been intrigued with making things out of metal for many years now. I currently own a Homier 7x12 lathe. I enjoy it very much.

My problem is in getting a MILL. I have toyed around with computers and programming/cad softwares enough to feel comfortable. I want a Mill, From reading I have learned to buy according to what my needs are.
Most of my projects so far for the lathe have not been much bigger than 8 inches. So I have been looking at mills for a table of 8 inches or so. Naturally I am gonna convert it to CNC. I have been looking at the Harbor freight MINI mill part #44991. It looks kinda small to me but very sturdy. The other is the Harbor freight Mini mill part #47158. It is the smallest one I believe Harbor Freight carries. Want to know some more info on these two machines. The store is local to me so that is why I narrowed it down to these two. I have 80 oz steppers but have sourced out 200oz steppers. I have my driver boards, Just need really good input about these machines.. And what they need to be CNC'd.. How much of the CNC conversion can be done with stock parts. Of course I will be upgradeing as my love grows for the machine.
I know I am not much of a poster but I have been reading and I am afraid that I just might jump the gun and get something that will end up being a waste of money. I don't want to do that. Thanks to all that takes the time to read this Book I've just posted..lol.. Any help or input would be greatly appreciated..
Respectfully,
-Joe

CerveloRod
03-14-2005, 12:02 PM
I built my HF44991 with 276oz/in steppers, direct drive, with the stock leadscrews, and I would not go down that route again. I feel that the gibs have to be left a bit to loose for the steppers to just move then table, especially in Y axis. I am currently upgrading to ball-screws and cannot decide between gear/belt reduction or direct drive.

If I was starting over, and was going to go direct drive I would probably go with something bigger than 270oz/in, or step up to servos.

I am using the Xylotex stepper board at 2.5amps. My steppers are rated at 2.8 amps so I think they are a good match.

Here are a few pic's as it was first built, I have changed it a bit now, the Y stepper mount flexed and I didn't like that so I made it more sturdy.
http://www.desmodue.com/~chadr/HFmill/

Rod