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DIY front splitter.

Old 11-24-2009, 02:29 AM
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Default DIY front splitter.

Started my DIY front splitter.

Started out with 5mm plywood and planning on reinforcing it top and bottom with fiberglass cloth for strength and stiffness. I’m thinking ill add some 1” square aluminum tubing on top of the splitter behind the bumper for added stiffness.

For mounting I have two bars that come down from my ISC swaybar brackets in the back. I added weld nuts in the frame so each swaybar bracket bolts with 8 fasters instead of 4. I bought couple of turn buckle rods from APR for the front, not cheap but nice.

The plywood doesn’t seem stiff enough by itself I am not sure what it will feel like when I add my fiberglass I am debating going to 11/32” ply before I start glassing.

Bob
Attached Thumbnails DIY front splitter.-p1010001.jpg   DIY front splitter.-p1010004.jpg   DIY front splitter.-p1010005.jpg   DIY front splitter.-p1010006.jpg   DIY front splitter.-p1010008.jpg  

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Old 11-24-2009, 02:44 AM
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Not bad, and excuse my question (if its too noobish) but why not use something better than plywood? Like aluminum, sheetmetal, or even a strong plastic?
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Old 11-24-2009, 03:01 AM
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Yah my vote goes for using a sheet of ABS plastic, as opposed to fiberglassing the wood (I think that's what you're planning anyway)

Plastic Sheet, Plastic Rod & Plastic Tubing - Buy Online
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Old 11-24-2009, 03:03 AM
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Originally Posted by 18psi
Not bad, and excuse my question (if its too noobish) but why not use something better than plywood? Like aluminum, sheetmetal, or even a strong plastic?

I think it is hard to beat plywood for the strength stiffness and weight and price trade off.

Pricing out a sheet of ABS plastic big enough and your getting pretty close to the price of a honeycomb core carbon piece from APR that comes with hardware. Aluminum thick enough to not bend every time you scuffed something would weigh a lot I think.

Chances are good that I will damage this thing at the track at some point. I want it to function well and I want it cheap to replace. a 4X8 sheet of 5mm birch plywood was $11. reinforcing it with fiberglass is going to be about $40 I think.

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Old 11-24-2009, 03:06 AM
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Not sure I understand plywood either. ABS isn't that expensive.

Plywood covered with fiberglass just seems like it will be heavy and a lot of work. You can get a sheet of ABS in .25 or .375 in the size you would need for $60-$100. Sure its more than plywood and fiberglass, but it sure is cleaner, lighter weight and probably more flexible and less likely to split. I like cheap, but I guess this is just one of the things I couldn't allow myself to go cheap on.
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Old 11-24-2009, 03:09 AM
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Originally Posted by bbundy
I think it is hard to beat plywood for the strength stiffness and weight and price trade off.

Pricing out a sheet of ABS plastic big enough and your getting pretty close to the price of a honeycomb core carbon piece from APR that comes with hardware. Aluminum thick enough to not bend every time you scuffed something would weigh a lot I think.

Chances are good that I will damage this thing at the track at some point. I want it to function well and I want it cheap to replace. a 4X8 sheet of 5mm birch plywood was $11. reinforcing it with fiberglass is going to be about $40 I think.

Bob
Very true. You should go ahead and make two to save youself the hassle though, unless you've made a template or something for that. Im starting to rethink my APR order. If mine ever cracks im going this route.
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Old 11-24-2009, 03:10 AM
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That's 51 bux. I asked around locally (TAP Plastics is the company name) and they told me they'd be able to sell me a sheet of strong/rigid plastic bigger than the size of your splitter for about 45 bux.

I think you should shop around. Its really not that expensive. And I haven't heard of anyone using plywood on a track car.
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Old 11-24-2009, 03:14 AM
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Originally Posted by 18psi
And I haven't heard of anyone using plywood on a track car.
Alot of racecars do. Savington does too, does he not?
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Old 11-24-2009, 03:16 AM
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Plywood? I REALLY don't think so.
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Old 11-24-2009, 03:18 AM
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You should add air stabilizers to the sides if you fiberglass it. That would be pretty dope.
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Old 11-24-2009, 03:20 AM
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He used birchwood
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Old 11-24-2009, 03:21 AM
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Originally Posted by Bassmachine
You should add air stabilizers to the sides if you fiberglass it. That would be pretty dope.
mad tyte jdm?

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Old 11-24-2009, 03:37 AM
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Originally Posted by 18psi
Plywood? I REALLY don't think so.
I use 12mm Birchwood with a 1" box aluminum frame. Lighter than an APR splitter of the same dimensions - I didn't even believe that one for myself until I met Manly Kao at SLB and he showed me his APR carbon splitter vs. the 12mm Birch splitter he had made. Same dimensions (the birch splitter actually mushroomed a little more) and the birch was quite a bit lighter.

ABS is not cheap, folks. I don't know what kind of material TAP recommended, but a 4x8 sheet of ABS was $130 or so for .250" when I got my quote from them. I think the cheapest I found it was $100 online, and the shipping was astronomical. I originally was going to use that, but the birch is 30% of the cost. For something that WILL get destroyed, you want it cheap and disposable, and stiff enough to do the job - weight is a nice afterthought, but not at 3x the cost.

Bob, I wouldn't even bother with the fiberglass unless you want the aesthetic qualities. I can pretty much stand on my 12mm birch splitter, and I don't have any forward supports on it either.

cjernigan crewed for APR's Rolex team this year at a couple of races, and IIRC he told me that 75% of the cars in the paddock at that event had wood splitters.
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Old 11-24-2009, 03:44 AM
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Originally Posted by Full_Tilt_Boogie
Yah my vote goes for using a sheet of ABS plastic, as opposed to fiberglassing the wood (I think that's what you're planning anyway)

Plastic Sheet, Plastic Rod & Plastic Tubing - Buy Online
The cheapest sheet of 1/4" ABS big enough to cut a splitter out of from that site is $107 "forming grade" before shipping. And in my opinion ¼” abs is not stiff enough to make a highly fictional splitter for a track car that can reach speeds of 150 mph. it is too flimsy. fiberglass glass reinforced plywood is much stiffer and I’m guessing about the same weight. The plywood by itself is lighter than ABS.

If I was going to spend close to that I would go to APR and get a custom one made out of honeycomb carbon. it is even lighter and it is stiff enough that you can stand on it. A custom carbon splitter is only $340. But I am trying to be cheap.

APR Performance - Front Wind Splitters

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Old 11-24-2009, 03:45 AM
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This is surprising to me. I wouldn't have imagined plywood to be lighter than ABS, though woods like Birch are pretty light weight and tough. I was always amazed at drum shells being so light weight with 9 ply birch. Savington has opened my eyes!

Sokath, his eyes uncovered!
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Old 11-24-2009, 03:49 AM
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Originally Posted by Savington
I use 12mm Birchwood with a 1" box aluminum frame. Lighter than an APR splitter of the same dimensions - I didn't even believe that one for myself until I met Manly Kao at SLB and he showed me his APR carbon splitter vs. the 12mm Birch splitter he had made. Same dimensions (the birch splitter actually mushroomed a little more) and the birch was quite a bit lighter.

ABS is not cheap, folks. I don't know what kind of material TAP recommended, but a 4x8 sheet of ABS was $130 or so for .250" when I got my quote from them. I think the cheapest I found it was $100 online, and the shipping was astronomical. I originally was going to use that, but the birch is 30% of the cost. For something that WILL get destroyed, you want it cheap and disposable, and stiff enough to do the job - weight is a nice afterthought, but not at 3x the cost.

Bob, I wouldn't even bother with the fiberglass unless you want the aesthetic qualities. I can pretty much stand on my 12mm birch splitter, and I don't have any forward supports on it either.

cjernigan crewed for APR's Rolex team this year at a couple of races, and IIRC he told me that 75% of the cars in the paddock at that event had wood splitters.
I guess the guy I spoke with (on the phone) didn't know what he was talking about then. I didn't see it (again cause it was a phone conversation) just asked for that thickness/approx size and that's what he said.

Oh well. I know nothing about splitters so I'll just shut up now
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Old 11-24-2009, 03:50 AM
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Now that I think about it, ABS would have to be pretty thick to be as stick as a thin peice of wood, and by that point would probably be significantly heavier. Sounds like wood really may be the way to go.

Ive just always hated wood. As a small child my parents had to keep me away from trees because I would become enraged and attack them. Years of therapy have helped me overcome this but apparently I still hold some prejudice.
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Old 11-24-2009, 03:56 AM
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Originally Posted by NA6C-Guy
This is surprising to me. I wouldn't have imagined plywood to be lighter than ABS, though woods like Birch are pretty light weight and tough. I was always amazed at drum shells being so light weight with 9 ply birch. Savington has opened my eyes!

Sokath, his eyes uncovered!
The construction method I was proposing thin plywood with a single layer fiberglass cloth was used in boat construction for many years and still is think unlimited hydroplanes. It made Stiff lightweight hulls able to take huge impacts from water slapping them.

Bob
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Old 11-24-2009, 04:02 AM
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Originally Posted by Savington

cjernigan crewed for APR's Rolex team this year at a couple of races, and IIRC he told me that 75% of the cars in the paddock at that event had wood splitters.
It would be soo ironic if APR was using wood too
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Old 11-24-2009, 04:06 AM
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True, but that wasn't exactly done with weight as a priority as much as strength. I was just assuming ABS would be lighter than plywood and fiberglass. Then again my mind is so stuck on plywood being 3/8'' and 1/2'' building material that breaks your back after you have to carry 20 sheets of 4'x8' up 3 flights of stairs... I guess something like thin birch isn't so bad, especially in splitter size. You know what they say about assuming though...
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