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howecnc
10-26-2011, 07:26 PM
Of the people who have bought a Mikini, how many of you with electrical issues have the machine base resting on your foundation floor?

I just installed vibration dampening leveling pads to my machine and the spindle is now performing more consistent than it ever has.

I am thinking of a car battery discharging when placed on cement could be a part of the problem/solution when using DC power but I am no expert.

SCzEngrgGroup
10-26-2011, 08:44 PM
I am thinking of a car battery discharging when placed on cement could be a part of the problem/solution when using DC power but I am no expert.

Of course, that's a bit of urban legend that just won't die.... It was true 50 or more years ago, when some batteries had rubber cases, but is absolutely not true for modern batteries with plastic cases.

By the same token, the DC spindle drive on a Mikini could not possibly care less what the machine is sitting on.

Regards,
Ray L.

SWATH
10-26-2011, 08:55 PM
I put leveling feet on mine but they aren't vibration dampening. Right now they are sitting on pieces of wood but I need to set them down on the concrete and level them soon.

mcphill
10-31-2011, 07:47 AM
I bought feet and never put them on (need to, front of the machine is about 1/2" lower than the rear so cutting fluid never drains). For now I am on concrete.

ROCKYMTN
10-31-2011, 01:11 PM
I've got my Mikini sitting in the garage on concrete. I used hex head bolts (I think 7/16" diameter) with the bolt head facing down on the concrete. Leveled it too using nuts on those same bolts to raise or lower as needed. I remember seeing an article about why dampeners are bad for a CNC machine as they allow too much vibration in the machine side. (can't seem to find the article now - of course!)

allenj20
11-01-2011, 12:40 AM
Mine sits on homemade hockey puck leveling feet not on the concrete. Now we really are chasing phantoms and ghosts :D

slowtwitch
11-01-2011, 06:54 AM
I have my mill sitting directly on the concrete. It's about 3/16" lower on the left, but, I'm going to keep it that way ...helps with the draining of the coolant ........actually, I'm to lazy to shim it up...lol

MichaelHenry
11-01-2011, 05:57 PM
I've got my Mikini sitting in the garage on concrete. I used hex head bolts (I think 7/16" diameter) with the bolt head facing down on the concrete. Leveled it too using nuts on those same bolts to raise or lower as needed. I remember seeing an article about why dampeners are bad for a CNC machine as they allow too much vibration in the machine side. (can't seem to find the article now - of course!)

It seems like bolt heads might put a very high loading on the concrete. Is that something to be concerned with?

Mike

ROCKYMTN
11-02-2011, 11:20 AM
It seems like bolt heads might put a very high loading on the concrete. Is that something to be concerned with?

Mike

So far so good. Residential concrete has a minimum rating of 2500 PSI so even if the entire machine was resting on one bolt I'd still be ok. Floor is 6" thick reinforced. I've got a 4500 pound republic lagun lathe also using same type of support only with 8 total feet. My floor slopes so I went ahead and leveled it. If my floor was level I would just place the machine straight on the floor and not bother with the feet.

chevalier
11-02-2011, 05:54 PM
FWIW. Industrial machine tools are levelled at installation with an accurate machine tool level sitting on the table for both X and Y direction. Its amazing how "flexible" even a rigid casting can be. Torsional twisting of the whole machine tool can introduce errors and even excessive wear. Even sunlight striking the machine can distort a casting. Perhaps this is a little bit anal for home machine tools but if you have access to a level then it does not take much to set it up correctly. A lot of people are not aware of the distortion that can be present in an otherwise "massive", solid looking machine.

I dont own a Mikini. I am watching this site to gauge the comments from owners to see if the Mikini is right for me. Spindle drive issues have me backing away from choosing the Mikini at the moment.

Just my 2 cents worth from the other side of the planet.
Greg

slowtwitch
11-05-2011, 06:04 PM
Well I got my lazy butt to finally level my mill. Actually, the mll wasn't to far from level as I initially thought. So i wipped out the old Starrett and went to work.

here is a shot of what I used to shim the mill......an electrical box cover :)

http://i46.photobucket.com/albums/f109/slowtwitch/PB050011.jpg

and here's the result......

http://i46.photobucket.com/albums/f109/slowtwitch/PB050010.jpg

Now I feel better...lol