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spongerich
08-07-2011, 10:12 PM
I picked up a mill at an estate sale today that's very similar to this one:
http://www.grizzly.com/outlet/9-x-32-Gear-Head-Mill-Drill-with-Stand/G0484

Unfortunately, the only way I was able to get it home was to disassemble it, so the base, column and head are now apart.

Is there a trick in getting this properly aligned when I reassemble it? I'm guessing it's going to come down to milling some shoulders and checking for square in each direction? Please excuse the newb-ish questions... this is my first exposure to a mill.

Thanks

Toolguy
08-07-2011, 10:23 PM
Put a dial test indicator in the spindle. With the spindle in neutral, bring the indicator down to touch on the table surface. Sweep the indicator around in a circle by hand with the machine off. When you get the same reading on the indicator all the way around, then the head is exactly square to the table.

spongerich
08-07-2011, 10:38 PM
Thanks!

Now I just have to figure out how to get it up on my workbench. It's 750 lbs and I've got about 2" of clearance to the ceiling on one side. Should be lots of fun getting her setup this weekend. I also grabbed a 9" Southbend lathe to replace the little 6" Atlas that I've been playing with for a few months.


Put a dial test indicator in the spindle. With the spindle in neutral, bring the indicator down to touch on the table surface. Sweep the indicator around in a circle by hand with the machine off. When you get the same reading on the indicator all the way around, then the head is exactly square to the table.

TGTool
08-07-2011, 11:04 PM
Ha ha. Reminds me of my trip with a benchtop mill. I'd disassembled it for moving and was setting it up again on the bench where it was to live. The only problem was the head. I could lift and carry it, but the ceiling was too low to straighten up and put it on the column. So I could lift but not install. I finally resorted to placing it on the table, jacking it up and putting 4 x 4 cribbing under it until I got it high enough to slide over to the column and seat. If I ever move out of this house and shop I'm in trouble. :D

Jaakko Fagerlund
08-08-2011, 04:12 PM
Put a dial test indicator in the spindle. With the spindle in neutral, bring the indicator down to touch on the table surface. Sweep the indicator around in a circle by hand with the machine off. When you get the same reading on the indicator all the way around, then the head is exactly square to the table.
That only ensures that the spindle axis is perpendicular to the table, but doesn't guarantee that the Z movement is perpendicular also. On manual machines without adjustments one can only assume it is also perpendicular, because correcting it is huge work.

Toolguy
08-08-2011, 04:44 PM
One can do more than assume. One can put an accurate square block on the table, then run an indicator up and down it with the quill. If it's off, one can shim or file the attach area to get it square.;)

Black_Moons
08-08-2011, 04:58 PM
One can do more than assume. One can put an accurate square block on the table, then run an indicator up and down it with the quill. If it's off, one can shim or file the attach area to get it square.;)

Highly recommend shims over filing. You can remove shims if you mess up. hard to unfile.

spongerich
08-09-2011, 12:27 AM
Highly recommend shims over filing. You can remove shims if you mess up. hard to unfile.

Ain't that the truth. I have a drawer full of files, but not a single unfile.

DATo
08-09-2011, 08:25 AM
Ain't that the truth. I have a drawer full of files, but not a single unfile.

Reminds me of something my brother, who is also a machinist, told me when I first started vocational school .... "If you forget everything else I've told you just remember one thing, you can always take it off but you can't put it back on."

I found out the hard way that this was good advice. One of the main reasons I learned to weld *LOL*

AiR_GuNNeR
08-09-2011, 08:36 AM
I have the same mill and had to do the same thing. I had mine with base in the back of my Vibe! That was one low riding car that trip.
The first thing you will need to do is square up the column to the table with shims. Cut your shims so they are shaped line a U to straddle the four bolts. I used an 8" machinists square on the table. Put an indicator in the chuck and run the head up and down. You will need to square both left to right as well as front to back. It's a real pain in the but, and you will need plenty of breaks as cranking the head up and down get old real fast. Once you have that done, you will need to square the head. You basically do it the same way, but you simply move the quill up and down rather than the whole head. Lots easier! I loosened the bolts holding the head in place and used a rubber mallet to move the head. There are nice dual indicator arms you can make that you chuck up and you simply tap the head until the two indicators read the same off the table.

Your Old Dog
08-09-2011, 08:57 AM
I use this:

http://raymondswan.com/shop/hsm/mill_tram_tool