where do you get bamboo plywood from locally? quickly looking at google prices for this **** is showing $140+ for a 4x8 sheet.

thats ******* expensive.

 

Mine is made out of laser cut aluminum

 

I think this is what I use. the sticker on it says 5mm though. made in china. The mohogany layer is paper thin, its mostly birch and fairly flat and smooth.

Project Panels Mahogany Plywood (Price Varies by Size)-1840 at The Home Depot


$24.80 in a 4X8 sheet

One sheet gets divided up into 3 pieces and laminated double layer thick in the parts that pick up my mounting and that stick forward of the air dam.

 

ABS plastic i'm assuming isn't strong enough until you get it so thick that it weighs a shitload, right?

 

Its plenty strong, its not stiff enough.

 

Definitely not stiff enough. I used 4 or 5mm thick ABS to replace the stock plastic undertray, and I couldn't imagine it being used anywhere it's not fully supported (aka, splitter hanging out front).

 

ABS is also higher density than birch plywood. Bout twice the weight by volume.

 

Bob which epoxy/resin combo do you use? I've used West systems stuff in the past but if there's a cheaper alternative I'll take it.

 

US Composites is cheaper, seems to generate the same results as west systems.
Epoxy : Epoxy Resins and Hardeners

 

Mine has Baltic Birch core (not the HDM stuff), Aluminum for some of the element, CF end plates and CF layer over the entire splitter with epoxy resin.
It can easily support the weight of a person (or more) despite being enormous -

 

not sure if its already been mentioned, but I used 1/2" fiberglass reinforced plywood for one on my integra. Its the stuff that trailer walls are often made of.

Wasn't the lightest thing in the world, but super strong and I could stand on it.

How do you guys typically attach them under the car? Any consideration to a design that can shear off easily in on off-track excursion or impact?

 

Are you doing any CFD on your splitter end features, long tail, etc? I'm curious how you came up with the splitter ends specifically.

 

Different schools of thought on that subject. I subscribe to the "make so it don't go nowhere ever" club. Mine is bolted to a steel frame. Others have tried to develop "shearing" designs and IMO it's a waste of time. Both myself and Moti @ Blackbird Fabworx have tested the hard-mounted splitter concept with boulders, shoveling into dirt, etc. and had no issues/continued to run the same splitter in the future. My opinion is that a shear-off design will likely end up causing more damage than it avoids.

The 949 Racing method uses cables in front, and the rear is not hard mounted, just set on top of a lip of the subframe. The advantage to this is the front of the splitter can lift if you scrape over a curb, but it is sturdy under downward pressure.

-Ryan

 

+1 to hardmounted. I use a steel/aluminum frame mounted to the front crash support. Rear is bolted to the subframe with two M6 bolts, nothing structural. In a mega-big frontal impact, the bolts will pull through the aluminum tube and the splitter will break free, but otherwise it will stay in place. No bumper attachments.

 

This is exactly how I had mine set up on my Honda. But I had a bad experience with it getting dug into a small ditch off track once. It was so strong that it wrenched the frame under the car. All above the suspension and engine mounts, but still not ideal. We yanked it mostly straight on a frame machine, and then I rebuilt the brackets out of a lot more flimsy steel.

When I eventually build one for this car, the plan will be to make it just strong enough to be functional, but the first thing to break in an impact.

 

Here's how I made my frame and mounted it. The forward uprights mount via two bolts, and rear use stock bolt holes, the two pieces of aluminum would hopefully act as a hinge and pivot after the front upright tears/pulls off the bolts sandwiching it to the crash support area. Those bolt heads are just slightly bigger than the holes so it should be able to rip off without bending that structure it's bolted too. Trapezoid frame is riveted to the splitter.

 

3/8 birch. 4 simple mounting points are 10x stronger than I ever expected. Used to use aluminum until an off at a very expensive, low track time event. The aluminum folded down on one side and back at the hot pit lane I couldn't kick, stomp, or jump my fat *** on it hard enough to rip it off. This is my old small alum. splitter. just 2 L shaped aluminum brackets with all thread on front, and oem bumper support rod at rear.

 

^ That looks really clean!

I've seen most people use 1/4 plywood and a fiberglass resin overlay.

 

So Birch, Birch, Birch, and 15/32", 15/32", 15/32" are the answers.

But where and which one should I get it?

Can someone help me find and post a link which one @ Home Depot?

 

PureBond Birch Plywood (FSC Certified) (Common: 1/2 in. x 4 ft. x 8 ft.; Actual: 0.453 in. x 48 in. x 96 in.)-332021 - The Home Depot