Max Metal aluminum sheet cutting specs

[MDCochrane]

Does anybody have experience with routing Max Metal sheets? Max Metal is a substrate of 2 very thin aluminum sheets separated by HDU core. The sheets are 4'x8' and 3mm thick (total thickness, the aluminum is much thinner).

I need to cut large numbers from this stuff. What do you recommend for the cutter and feed rate? I don't have vacuum hold-down, so I'm planning to leave an occasional tab in the bottom layer of aluminum to keep the cut-outs from shifting. Sound like a reasonable strategy?

Thanks!

Mike

[jerry_stanek]

I cut Komalu and Dibond that is the same kind of material. For large letters I use a 2 flute down cut bit running at 4.5 ips in one pass I do cut into my spoil board to get a good cut as the bottom has a small burr on it just a quick swipe with a sanding blok and it is good to go. If all you have is an upcut bit mirror your letters and cut upside down.

[Dish]

When you are cutting this material are you using any lubricant?

[MDCochrane]

Hey Jerry,

Yes, I have a 1/8" spiral downcut FEM that should do for this. What RPM speed would you recommend @ 4.5ips? 16k?

Mike

[knight_toolworks]

so far if it cuts like dibond bits are not critical. Hold down is the key worry so choose a bit that helps. usually a straight bit is a good choice and a climb cut to keep the parts in place. I have cut it with a 1/16" bit with no problems in a single pass. a 0 flute works well if the pieces won't lift up. But it cuts like butter so it is not a big problem.

[MDCochrane]

Dish,

I had not given any thought to lubricant... this aluminum is so thin you could probably cut it with a good pair of kitchen shears. Would you maybe recommend a silicon spray on the sheet before cutting?

[Brady Watson]

No lubricant is required for cutting AL with the correct geometry bit. Nor is it advisable with a wood decked machine. When you start to get over 1/2" thick AL heat becomes an issue, but compressed air blowing on the bit is adequate - even airflow from dust collection is fine. In extreme cases, you can exploit 'evaporation is a cooling process' by using some denatured or rubbing alky, but that presents a fire hazard - especially with vacuum(!)

Any single or 2-flute straight or spiral 'O' made for routing AL is fine. Onsrud, Harvey Tool etc.

-B

[Dish]

Thank You Brady for that information!

[GeneMpls]

The core is actually abs plastic. We use a lot of it in our sign shop -good
stuff. We use premask tape on the spoil board and the bottom of the ACM
(aluminum composite material) and banner hem tape or carpet tape to
hold it down. Then cut through it and use smooth round rod (or punch) to dress
the bottom burr. Gene

[sneakers]

This stuff cuts really well but I found that by running a putty knife along the bottom edge you will see a thin wire edge just peel away leaving a nice clean but not sharp edge.

Gary