I got bored...

[The_Doctor]

If Thorlabs' are ground plates, and fairly small, then maybe they use a grinding powder on a flat glass slab to lap them. That would put the price up a tad.
A cheaper way would be to mill them in a very precise heavy milling machine, with slow light cuts.

[laserlackey]

I don't see why you would need to grind it when Mic6 is flat to .005" from the mill. Machining at 10k RPM with a 10-insert fly cutter isn't going to get that flat because the vice is probably only +\- a couple thou per foot.

Alcoa ships Mic6 vinyl coated. I'll check this with my CMM on Monday just to see what it is. I literally pulled this from the scrap bin, peeled off the vinyl, and stuck it in the mill.

[The_Doctor]

I don't see why you would need to grind it when Mic6 is flat to .005" from the mill. Machining at 10k RPM with a 10-insert fly cutter isn't going to get that flat because the vice is probably only +\- a couple thou per foot.

Good point. I never used anything thicker than 12mm, and when flattening stuff it was on thick MDF with gluespray bonded fine emery paper on it. Crude but effective when doing things by hand, so can get flatness such that you feel hard suction when pulling plates apart. (And an awesome brushed finish too if the emery paper is kept free of accumulating powder). But if the stock started out with exemplary flatness I'd not be so concerned with gently grinding off any burrs from drilling and threading, as making sure there are no burrs in the first place. I doubt I've ever used material that good.

[laserlackey]

It's all about 1" material. Anything 7/8" and under is only .015"/ft. which is terrible, but it's because the continuous pour is only cooled from one side. With 1" material the pour is cooled from both sides and stays nice and flat.

In this application, I'd imagine thicker is better for flatness and for thermal reasons. This thing will soak up a lot of heat. Oh, and it fits in a medium flat rate box from USPS, too

[andy_con]

Awesome work, I was thinking of doing something similar buy also with water cooling. It would make a nice test bed for trying out new setups

[The_Doctor]

It's all about 1" material. Anything 7/8" and under is only .015"/ft. which is terrible, but it's because the continuous pour is only cooled from one side. With 1" material the pour is cooled from both sides and stays nice and flat.

In this application, I'd imagine thicker is better for flatness and for thermal reasons. This thing will soak up a lot of heat. Oh, and it fits in a medium flat rate box from USPS, too

Not for this, I just meant in general. I've never made an optical deck. I used 12mm for a projector base plate, and that's thicker than many people use. Nice info about the cooling both sides on 1 inch plate..

[clickamouse]

Why 4-40? I do my mounts with 8-32; is this overkill?

...Mike

[sugeek]

Why 4-40? I do my mounts with 8-32; is this overkill?

...Mike

It is a standard screw and easy to get.

Nice job Andrew an optical breadboard makes playing with optics and lasers so much more fun and easy!

Adam

[laserlackey]

Why 4-40? I do my mounts with 8-32; is this overkill?

...Mike

All of the components I have currently are 4-40. Version 2 will probably have a mix of 8-32 and 4-40 on alternating .5" centers.

Yeah, it probably is overkill, but Platinum and I have been doing a lot of experimenting lately and with a CNC it's the same amount of work to make 500 holes as 950, so I figured why not. .25" centers should fit just about anything I could ever want to put on there.

[Laserman532]

you were bored...