Ideal base plate thickness...?

[mixedgas]

Thanks all...
I tempted to say what the heck and go for the 12mm... I'm only likely to do this once (he says!)
And if it's worth doing, it's worth doing properly
I'll put a word in a uni and see if I can get my plate cut on the water jet cutter.

Ta,
Dan

If you get it waterjetted, have them do the hole grid about 5 drill sizes down from your final tap drill, makes it far easier to do the 1" grids.

Steve

[danielbriggs]

Thanks I'll bear that in mind.
I was planning to 'tap on demand' where and when. But we'll see how the design goes.

Cheers,
Dan

[dave]

I believe the cast aluminium plate is better than the rolled stuff ( but it is a lot more expensive )


I find drilling and tapping on demand the better, faster way to go..

[Agent C]

Has anybody tried the Alucobest paneling from 8020? It's a composite of two 0.020" aluminum sheets bonded to polyethylene, 6mm think sandwich. I have a tendency to think space-age when bronze age will do just fine.

[danielbriggs]

Has anybody tried the Alucobest paneling from 8020? It's a composite of two 0.020" aluminum sheets bonded to polyethylene, 6mm think sandwich. I have a tendency to think space-age when bronze age will do just fine.

Heatsinking issues?
And although a composite, wouldn't the polythene be more flexible?
Also the £££/$$$

Dan

[buffo]

Water-jet cutting? Well, I suppose if you've got free access to the equipment it makes sense, but otherwise...

I've cut 1/2 inch aluminum with nothing more exotic than an electric jig saw with a standard metal-cutting blade. Sure, you have to go slow,(otherwise the teeth will get plugged up with the relatively soft aluminum), but it does work... It you've got a band saw, or even a carbide-toothed blade, it will work quite well.

Considering that you're only talking about a few cuts, it seems overkill to go to the expense of a water jet... Why not cut it yourself?

Adam

[trwalters001]

When I was making telescopes instead of laser projectors, I was cutting 1/4" aluminum plate with several passes of a router with carbide cutter.

Loud! But it works well.

[danielbriggs]

Water-jet cutting? Well, I suppose if you've got free access to the equipment it makes sense, but otherwise...

I've cut 1/2 inch aluminum with nothing more exotic than an electric jig saw with a standard metal-cutting blade. Sure, you have to go slow,(otherwise the teeth will get plugged up with the relatively soft aluminum), but it does work... It you've got a band saw, or even a carbide-toothed blade, it will work quite well.

Considering that you're only talking about a few cuts, it seems overkill to go to the expense of a water jet... Why not cut it yourself?

Adam

I have a couple of tools I could use in the garage, however the CNC mill doesn't have the capacity for a 500x300mm job
So this would have to be done by hand (unless I do some tedious multipart cutting+aligning process, but actually I don't think the table size would accommodate such a plate - it's only a small machine)
The only sticking part is the 60 deg chamfer needed on two of the sides - I don't really want to file that. I'd rather mill it or otherwise.
Waterjet cutting is relatively new to me, and I've never used one, so would be a good learning experience. I think they have a couple of 5-axis water jets at uni - so I'll enquire. (I'm not going to get my hopes up, as just because they have the tools doesn't mean I will be able to use them - especially for a non-course related project)
But I've been in contact with my materials prof. and he suggested EDM as an option too. I'm back there in a couple of weeks, so will probably have a quick chat in person to see if I can sort anything.

As for cost; the material is the only thing I need to fork out for, as it's going to cost the same whether I use EDM, water-jet or a hacksaw and a jar of elbow grease

Thanks all for the input - much appreciated.
I still have a lot of planning to do first though!

Ta,
Dan

[danielbriggs]

I've just realised - I should try and get it laser cut!
The irony...
Muhahah!

[Laser Ben]

When I was making telescopes instead of laser projectors, I was cutting 1/4" aluminum plate with several passes of a router with carbide cutter.

Loud! But it works well.

HSS is actually preferable to carbide for Aluminum. It can be made sharper then carbide for endmills and typically provides a cleaner cut. I would use a HSS mill with a really steep flute line. Get one with 3 flutes as it will reduce chatter.