Square a tabletop along X/Y axis

[trev]

Is there a trick to aligning the edges of a table to be perfectly squared along the X and Y axis? Right now I'm just lowering the Z to right above one corner, then moving it along one axis to the other corner and making sure it's still above, making any minor adjustments and then re-checking. Please tell me there's a better way. :)

[trev]

Just to clarify, by table I mean I'm putting an actual tabletop on the Shopbot for engraving. I don't mean the Shopbot table.

[Kyle Stapleton]

If the table of the Bot if square just flush it up to that, if not us the bot to cut the table of the bot square first.

[myxpykalix]

When i set my table (the one secured to the bot) up initially i did like you described, i put one edge at 0 then ran the bit down in the X aligning the table and secured it there.
From then on whenever i throw something on the table i just line it up with the X axis side and i know it's square to the bit without having to do all that fussing, takes a few seconds.:eek:

[gergistheword]

After each time I flatten my table I run a file I created that engraves a grid on the table surface. Sometimes I'll even run a sharpie down the lines to make them easier to see. I use these lines to align my pieces. This way, Even if I'm in the middle of the table I know that I'm square to the tool travel.

[GeneMpls]

After each time I flatten my table I run a file I created that engraves a grid on the table surface. Sometimes I'll even run a sharpie down the lines to make them easier to see. I use these lines to align my pieces. This way, Even if I'm in the middle of the table I know that I'm square to the tool travel.

Exactly what I do- works for me. I also added this to my spindle... my files
run much better now BTW. Gene

[scottp55]

Same here. .02" on a 1" grid, .04" deep every 6". Helps make it easy to spread my screw holes out on protos.

[bcondon]

Works perfectly every time.


Flatten you top completely.

Screw a piece of plywood 3/4" high, 2 " x 96

Now set you 1/4" router but 1/8 or less into the side of the piece of plywood.

Using the K command and just run the bit down the length of the plywood making sure it takes "some amount" off all of the plywood.

This will give you a permanent edge for your workpiece. What I do is have another shorter piece of plywood with parallel edges that I place against my permanent edge which gives you a perfect offset from the permanent edge.

I place my work piece against that and clamp it down...

REMOVE the offset so you do not cut into it. I place my ORIGIN at the workpiece and ready to work.

In the picture the P piece is the Permanent edge, offset is my plywood piece and Workpiece is given.

You could screw your table against the permanent fence or use an offset piece.

Works every time...

Bob Condon

[JustinW]

I use a setup like gergistheword.
Last part of table surfacing is a grid of .5" lines.
I made a speed-square out of polycarbonate, and a few flat pieces. Slot them as needed in the grid, and butt the material up to the Poly.
The grid is set in relation to the prox switches, so alignment is quick and repeatable. For larger production runs, I'll align an MDF fence to the grid, screw it to the table, and offset 0,0 by -.5".

I discovered this method when I cut to deep and gouged the sacrifice board early in my shopbot use, and swear by it now.