Table bolt was missing

Tim9

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Just thought I’d pass this on. I was milling a chunk of aluminum mounted in vise on my Millrite MVI. Moving X axis from left to right and depending on the amount of cut each pass, I was ending with an angled cut somehow.... but most of the time it appeared as an arched cut.
I was really bewildered. Checked the vise mounts, gib locks, feedscrew, etc. I checked the schematic and couldn’t come up with anything. Finally I grabbed a mirror and looked at the underside of the table. I then saw the culprit. On the right side..... ( not the left side with the gib locks).... there was a missing 3/8” x 16tpi socket head bolt. I’m thinking this holds one end of a table gib ???
Not 100% sure but I’m thinking that the lockdowns were holding the part mating against the dovetail of the table and this was acting like a spring on the table on heavy cuts.... hence the arched cuts on my chunk of aluminum. FWIW... I couldn’t get the threads to line up centered with hole until I loosened all the gib screws on left of table. Then I used that brass line-up bar I made which was tapered and had a sort of ball head on its end.
 
Here’s a few pics of what I was talking about 978C20C8-5A34-43E0-B0B2-A43AA407B2BE.jpeg978C20C8-5A34-43E0-B0B2-A43AA407B2BE.jpegDE94886B-B61A-4641-901D-AF8627597117.jpeg5D0ECB52-2C5C-47BB-8274-85621ED3AB61.jpeg
 
Just another update. When I got everything together with missing bolt replaced... I thought I had everything fixed. Then I took another kind of hard cut and I had an angled shaped cut.
So I used a magic marker and marked the ram to turret with a line. Took another cut and my line moved. Turns out that one of the bolts in the ram was too long and although it felt tight...it was not locking the ram. Shorter bolt to replace the one in there and I think it’s now fixed.
FWIW.... I’m just getting around to using this mill so these issues could have happened anytime in past..... only God knows when.
 
By the way...just wanted to ad this tidbit. When tightening the bolt on right side of table it’s advisable to move the X axis all the way to the left. Crank the table all the way to the left and then tighten the bolt. FWIW... there’s also a set screw right next to the bolt which locks the gib out so that it’s not too tight.....same set up as those on the left of the y axis lock down.
Anyway, what I ran into is when I cranked the X- axis to the left it was noticeably binding. It got real hard to crank the handle. As soon as I loosened that bolt the effort to move the table crank immediately got smoother. I’m assuming that when I tightened it with the table in the middle....that the table locking wedge bar which is held on by that one missing bolt....ended up like a gib screw too tight. Bottom line is to make sure the table all the way to the left and then tighten it.
 
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