10 inch Disk?

[Dgrose]

How do I make a 10 inch disk from 3/8" plate? I can cut with plasma cutter but how do I get the edges trimmed? I have a 10 inch rotary table but how do I clamp it to the table and mill the edge? I have a big enough lathe but you can't hold it and cut the edge? How do I make this disk round by milling the edge?

 

[Alcap]

Will your plate have and holes when finished ? Could drill and bolt something to the bottom or right through.If your rotary table has a 3 jaw chuck you could tack weld a round slug under it then grind the welds off . I’m sure there are other ways

 

[Alcap]

I was just thinking, If your rotary table is big enough or a sub plate you could just put clamps around the outside and remove the clamps as needed as you rotate the table , putting it back after cutting where the clamp was .

 

[mmcmdl]

I have a big enough lathe but you can't hold it and cut the edge?

Sure you can . Use a pressure pad up against your 3 jaw chuck .

 

[tq60]

Place equal height spacers under plate to support it to allow gripping on the lower 1/8 inch of the plate leaving 1/4 inch above jaws.

Cut to size.

Flip over and finish.

Did this in lathe with a thick round foud at scrap yard

On ours we had pocket on one side so cut that an held by it for finish cut.

Sent from my SM-G781V using Tapatalk

 

[Jimsehr]

I silver soldered a 3 inch disk to a plate . Then turned od then reheated and removed disk.
Jimsehr

 

[rabler]

I'd probably try CA to put a smaller disk on it to clamp in the 3-jaw, and add a pressure plate with the tailstock.

 

[woodchucker]

I'd probably try CA to put a smaller disk on it to clamp in the 3-jaw, and add a pressure plate with the tailstock.

That's what I would do.
I have used this quite a few times. I would not trust the glue alone, so a pressure plate is good insurance.

BTW if you do flame or plasma cut, give yourself extra space, then sand/grind the edge.. remove the flame or heated edge. I went through quite a few carbide cutters .. you need to get under the flame cut.. mine was an interrupted flame cut because it was done by hand. On the second one I wised up and ground it off before turning it.

 

[Shootymacshootface]

Sure you can . Use a pressure pad up against your 3 jaw chuck .

This is what I would do. You could even use some super glue for some extra grip.
Joe Pie has an excellent video on pressure turning.

 

[Mitch Alsup]

How accurately round does it need to be ?

0.100 almost any reasonable method, including griding by hand, and measuring with tape
0.010 slap the sucked on a rotary table and use an end mill (keep at least 2 clamps on at all times.)
0.001 sliver solder to blank than can be held in lathe chuck
0.000,1 Out of my knowledge base level.