# Mill Table Covers



## Buffalo21 (May 9, 2020)

As I’ve posted before, I have a 12” x 24” aluminum plate bolted to the Rockwell’s (model #21-100) table, with 253 drilled and tapped holes. I made it to do a series of jobs. Then decided to keep it on the mill, as I have 2 others, I remounted the vise and use the mill as usual, the additional table space is handy. The one drawback is the swarf gets into the threaded holes, making clean up a chore, so I roughed out a couple of lexan table covers. They cover the table, during normal use, when I remove the vise, they are easily removed to allow access to the the threaded holes. The lexan was scrap left over from another job.


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## Mini Cooper S (May 9, 2020)

Nice way to keep the chips out of the holes. sure speeds the cleanup process.


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## GunsOfNavarone (May 10, 2020)

I really dig the idea of a fixture late bolted to the table. Besides the chips in the holes, any real problematic cons to it? Seems as if you could really have much more options for the Y axis on placement (rather than the standard 3 channels I have to pick from. But yeah, been thinking about this the last 5 months or so. I know it would be hella cheaper to make it myself, but the time/patience needed to do that, not to mention accuracy is important...but I won't be going to Crummy brand level/ cost though.


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## Buffalo21 (May 10, 2020)

Other than clean up, I find no real negative to leaving the plate bolted to the table, there are 127 holes tapped to 1/2”-13 and 126 holes tapped for 3/8”-16. The two sizes of all of my hold down hardware. I made it originally to re-machine some pump casings, the are odd shaped and will not fit into any vise I have, the plate allowed me to bolt it directly to the plate, that made the machining very easy.

the Rockwell table is roughly 6” x 23”, so the plate actually doubles the size, which can be handy. The plate is also orientated to have the vast majority of the over hang in the front, the back plate edge toward the column is actually overhangs the table about 1/4” less than the coolant lip on the back of the vise.

As I have 2 other mills (Jet JVM-836 and the 1940 Bridgeport w/mill drill head) leaving the plate on the Rockwell is not inconvenient in any way. Really I see it as an asset, I just wish I’d done it sooner.


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## GunsOfNavarone (May 10, 2020)

How thick is it? What process/steps did you use (or recommend) to make one? Seems like bolting the piece to table and setting your hole spacing would keep the best accuracy, but I'm guessing you wouldn't have enough movement to not have to reposition. Setting it on top of wood so as to not worry about drilling into table etc...?


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## Buffalo21 (May 10, 2020)

It is a piece of 1/2” aluminum jig plate, if I had a thicker piece in stock, I would used it, so far the 1/2” plate has been adequate for my usage.  I laid it out the bolt holes with a square and a Sharpie, it ended up being 11 holes wide by 23 holes long. The drilled all of the holes at 5/16”, circled the one that needed to drilled out to 7/16”, then using the built in tapping head in the large Jet drill press, ran the necessary sized roll tap, with lube through each hole, then touch each hole with a countersink. Start to finish about 5-6 hrs.


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