"Squaring up" a steel plate on the mill

[Pcmaker]

Any tips on how to square up a steel plate on the milling machine? I've done this a few times and the workpiece ended up being trapezoidal in shape rather than square.

I fixate the workpiece on the milling table with 123 blocks and toe clamps. I mill one side, then the other side, then the remaining 2 sides.

 

[Ulma Doctor]

what type of mill do you have?
everything will come out trapezoidal to some degree (usually measured in thousandths, ten thousandths , or millionths for the anal retentive)
how much out of square are we talking about?
other questions to follow upon the answers to these questions

 

[MyLilMule]

First, you need to make sure your mill is trammed correctly. Then you have to make sure whatever you are using to hold your work piece is trammed to the mill.

 

[GT-6 Racer]

You didn't say how big a plate you are milling and if you had to unclamp it and turn it? If moving the plate you will have to very carefully tram it back in. Of course squareness will depend on rigidity and accuracy of your mill and your skills in tramming in after a move. If doing a fair number of parts it might be interesting to make a fence out of a steel block bolted to the T slots and mill it in place so you are certain it is square to the X or Y travel as you need and use that as a reference.

 

[mmcmdl]

Use some tee slot blocks for two sides , then use a square on the blocks to locate for the remaining 2 sides . Really not enough info provided , but this is just the normal route .

 

[Net30]

Joe pie method. Youtube. Side mill all 5 sides if possible then flip and mill last side, or mill the equivalent of a parallel into the part. If you are unable to make Square parts, I'm going to guess you are a complete beginner and when I was at that point about a year ago, Joe pies videos probably help me more than anything.

 

[Just for fun]

Is your mill trammed?

 

[ChazzC]

What @Net30 said:

And:

Plus others. Also TRAM