PSA

Googled alumalite when looking for splitter material for our latest build. Typical sign shop website offered what I though was alumalite (invoice states alumalite) but got something called alumacor.
Wasn't until we had it chopped it that we realized it was different.

Alumalite is the stuff many of us are familiar with. Corrugated ABS interior. The core has a septum so the sheet is kind of a three layer club sandwich.

Alumacorr is this new stuff, 1mm thicker a bit less rigid and about 15% lighter. Dents easier than Alumalite. I think it'll work just fine for us, just thought the info worth sharing.

 

This is where I'm going to get the last tenth of a second to beat my buddies.

Thanks for the share!

 

Curious, what local sign shop are you purchasing from?

 

Overnight Grafix but I can't recommend them. Delivered late, bait and switched. Just google "sign materials" or "alumalite" or "alumacor". Dozens of other companies.

 

YMMV, but I made an alumalite splitter the same size as my plywood splitter (that desperately needed replacement) and they ended up being the same weight per my scale. Moving forward, I'm just sticking to trusty plywood... Whatever small weight savings is there doesn't seem worth the pain of trying to source the alumalite that you'll pay a premium for.

 

Sweet, thanks Emilio. They were on my radar, but I’ll look elsewhere.

Pad, appreciate the heads up as well! I didn’t realize it probably sounded like I was inquiring about splitter materials. I actually wanna use the alumacorr to experiment with a set of barge boards for my car. I’ll still be sticking with trusty plywood for my splitters as well.

 

Old data at this point, but worth tagging along on this thread!

Back in 2019 during the 9LR prototyping on my car, we tested several materials for a 3" splitter, airdam, and the mounts(sturdy bois). One splitter material I really liked was because it was so light and super easy to cut/modify by hand. It was called aluminum composite material(ACM):

The 8mm seemed too thin and it would flex easily. Moved up to a 10mm and it seemed much better. Unfortunately, it wasn't quite stiff enough to function as a protruding splitter. It would visibility bend down coming into T1 at Road Atlanta for example.

HOWEVER, I used that 10mm ACM as a "belly pan" or "undertray" behind my airdam from 2019 to 2024 and it was great. It smacked a LOT of curbs and was so much lighter than my birch splitters. Again, it was really easy to cut even with my unskilled hands.

I finally killed it off with a pretty big off, ramping over some sand berms at CMP last year. I managed to hammer it flat and do another race after this actually.

 

I've had 6mm alumalite as barge boards on my car for the last ~6 years. It's held up quite well for my track/street duties and is just recently getting to the point of needing replacement due to some "speed bump" rub zones wearing through the aluminum layer.

 

Thanks for the feedback guys! Flier, that's really interesting you went with the ACM. I thought I read that material was actually heavier than the Alumalite/corr. My current skirts are made of ACM but they're only maybe three inches wide at their widest point so weight isn't as much of a factor for them I guess.

Pad, good to know the 6mm Alumalite has held up for your barge boards. 6 years far surpasses my design requirements as I'd expect anything on my car to get damaged well before then haha.

I've been searching for where to get an Alumalite/ACM panel since last week and it just occurred to me yesterday that I can get either through my dad, who's worked in industrial ceiling/wall panel sales his whole life Dunno why it took me half a week to think of that. I'll likely just see which of the two I can get cheapest/easiest through him, since my first attempt will likely be more of an experiment than a final design anyways.

 

So it looks like ACM is same basic material as alumalite, just not internally webbed/corrugated. Seems like it would be heavy. I have no experience with it. We used 3-4mm alumalite for anything other than splitters. Heatshields, undertrays, barge boards, end plates. The 10mm was the min that would survive as a cantilevered splitter structure. 15/32 Birch ply was second best but a bit heavier and more flexible. Birch ply definitely easier to work with though. I think the other reason we shifted to alumalite was for appearance. It can be painted or covered in vinyl and look sharp.