Front Reinforcement Plate...in carbon fiber!

[leftfootbr8king]

Adjustability as well* If you’re going custom you might as well allow yourself the ability to add or remove splitter length to dial in aero balance.

It’s fair to have a splitter that goes to the back edge of the felt skid plate but I wouldn’t have it go back much further than that.

[Hujan]

Put me down for one.

[reidetailing]

Thanks for the info on this.
Please put me down for one too if this does go into production.
Would be happy to support this!

[bigjae1976]

I sent off the prototype to DRLane. Should be there late next week.

For the past year it takes the stars to align to get anything done. Supply chain problems! Right now, I've been waiting on the correct epoxy hardener or a month now. Should have it this Fri. Also waiting on more gel coat to make an E46 M3 hood mold...2 weeks so far. These items have a shelf life so I have to buy in small batches.

Hopefully I can make an updated part this next weekend.

[hsaguirre]

Not that I use it often but curious if any issue jacking from the front Jack pad against the carbon?

[bigjae1976]

Originally Posted by hsaguirre

Not that I use it often but curious if any issue jacking from the front Jack pad against the carbon?

No. Carbon is stronger and stiffer than aluminum.

Carbon has poor resistance to elongation, and strength falls off sharply once the tensile strength is exceeded.

[roastbeef]

Originally Posted by bigjae1976

I ran the numbers. Worst case here. If I can get at least 8 paid up, price would be around $900. The most I can do is 12, pricing would be around $800.

Even worth exploring?

I’m in.

[admranger]

Originally Posted by bigjae1976

No. Carbon is stronger and stiffer than aluminum.

Carbon has poor resistance to elongation, and strength falls off sharply once the tensile strength is exceeded.

What's the glass transition temp of the resin you're using?

[bigjae1976]

Originally Posted by admranger

What's the glass transition temp of the resin you're using?

You mean the max temp rating of the epoxy? Typically 300-400 degrees.

[admranger]

Originally Posted by bigjae1976

You mean the max temp rating of the epoxy? Typically 300-400 degrees.

The glass transition temperature, often called Tg, is an important property when considering polymers for a particular end-use. Glass transition temperature is the temperature, below which the physical properties of plastics change to those of a glassy or crystalline state. Above Tg they behave like rubbery materials. Source

My concern is track exhaust temps and how long that heat will have to heat the shield. We see 275+ deg F oil temps from time to time and you are inches from the oil pan.

I'm not saying things will go wrong, just maybe monitor it (low temp brake temp paint?) or put some heat shielding between the reinforcing plate and the exhaust/oil pan/hot stuff.

[bigjae1976]

Originally Posted by admranger

The glass transition temperature, often called Tg, is an important property when considering polymers for a particular end-use. Glass transition temperature is the temperature, below which the physical properties of plastics change to those of a glassy or crystalline state. Above Tg they behave like rubbery materials. Source

My concern is track exhaust temps and how long that heat will have to heat the shield. We see 275+ deg F oil temps from time to time and you are inches from the oil pan.

I'm not saying things will go wrong, just maybe monitor it (low temp brake temp paint?) or put some heat shielding between the reinforcing plate and the exhaust/oil pan/hot stuff.

On my E46 plate, the header flanges are close to the plate like the E9X M3. The epoxy is yellowed from the heat. I’ve put aluminum tape over that spot. I’d need to make a new part to see if the aluminum tape is enough to prevent yellowing. I’m confident the plate isn’t deforming, my E46 plate comes on and off with no issues. There should be plenty of airflow to keep temps in check while the car is moving. I've gotten oil temps up to 280 degrees in the TX heat.

If the epoxy becomes soft it should harden up again as the part cools. I’d be pretty sure that cycling would deform the part or at least the layers would start to delaminate.

Interesting input…thanks!

[bigjae1976]

V2 bagged up. I should be infusing it later today or tomorrow.

Similar layup as the first. I use 4 layers of carbon between the bolt holes. I used a unidirectional fabric vs a 2x2 twill on this one. We'll see if that adds some stiffness without adding weight.

[rhyary]

How do you measure the change in stiffness?

[bigjae1976]

Originally Posted by rhyary

How do you measure the change in stiffness?

Nothing scientific - just put it on some blocks and stand on it.

[roastbeef]

Originally Posted by bigjae1976

Nothing scientific - just put it on some blocks and stand on it.

thats the way. whenever i'm drilling something, i just torque it in my hand to figure out where the weak points are and where i can drill more. lol

[bigjae1976]

Originally Posted by roastbeef

thats the way. whenever i'm drilling something, i just torque it in my hand to figure out where the weak points are and where i can drill more. lol

🤣🤣🤣…I guess I could setup a dial gauge and measure the panel deflection. Not sure if that is the answer either.

[roastbeef]

Originally Posted by admranger

The glass transition temperature, often called Tg, is an important property when considering polymers for a particular end-use. Glass transition temperature is the temperature, below which the physical properties of plastics change to those of a glassy or crystalline state. Above Tg they behave like rubbery materials. Source

My concern is track exhaust temps and how long that heat will have to heat the shield. We see 275+ deg F oil temps from time to time and you are inches from the oil pan.

I'm not saying things will go wrong, just maybe monitor it (low temp brake temp paint?) or put some heat shielding between the reinforcing plate and the exhaust/oil pan/hot stuff.

sounds like heat wrap would be relatively inexpensive insurance. the subframe is aluminum, so that helps by being less conductive.
not to get too off topic, but i've been using this stuff for a few years now on the underside of my carbon intake plenum. its lightweight, and resilient. i wash my engine bay a couple times a year and it shows no signs of peeling.

Originally Posted by bigjae1976

🤣🤣🤣…I guess I could setup a dial gauge and measure the panel deflection. Not sure if that is the answer either.

i don't know if it would even be an important metric to measure. it seems like it would see horizontal or lateral compression or expansion rather than bending (as if you were standing on it). certain structures can be very strong one way, and relatively weak another direction. unless you're going to regularly sell these as a company, i wouldn't expect you to construct a jig to compress these or pull them apart to see how they compare to the aluminum pans.

[bigjae1976]

Originally Posted by roastbeef

i don't know if it would even be an important metric to measure. it seems like it would see horizontal or lateral compression or expansion rather than bending (as if you were standing on it). certain structures can be very strong one way, and relatively weak another direction. unless you're going to regularly sell these as a company, i wouldn't expect you to construct a jig to compress these or pull them apart to see how they compare to the aluminum pans.

I am almost finished another one. I used a 400gsm unidirectional fabric to connect all of the bolts holes. So its like a substructure inside of the entire part. I just used scraps of a thicker 668gsm 2x2 twill on the first one.

The direction of the weave will drive stiffness. You can use biaxial fabrics between layers or layup each layer so the weave is alternating +/- 45 degrees. A twill has strands or tows in two directions so its stiffness and strength is split in half vs a unidirectional fabric. Using a unidrectional fabric can provide the same stiffness at half the weight.

So this one I just finished SHOULD be lighter. I'll admit...I just put full size scraps of CF cloth on the first one. On this one, I trimmed up everything a lot better plus the unidrectional fabric should be a little stiffer while saving some weight.

[bigjae1976]

V2…used a 4mm core instead of a 2mm core. Also substitutes 2 layers of 2x2 twill for 2 layers of unidirectional fabric - came in at 5.4 lbs but was noticeable stiffer.

After laying on my back staring at the oil pan on my car for an hour, I’m thinking that this plate is mostly protective. It just bolts onto the subframe. Unlike the E46 where the plate adds a significant amount of stiffness since it bolts to the subframe, body, and control arms.

V3 I went down to 2 reinforcing layers instead of 4, same 4mm core. I’m going to cut the flange off the edge which do nothing for a carbon part. One the OE part the bends add stiffness. It consumed less epoxy so hoping for 4.5lbs all trimmed up with better stiffness than V1. Confident on being stiffer (🤣🤣&#129315 but not sure I’ll make the weight.

V2 done, just needs to be trimmed.

V3 is curing.

[rg1220]

Nice! Looking great! I've been wanting to do some CF. Just got a vacuum pump. What resin system / company are you using?

[VictorH]

Wow! That is really impressive and probably much better quality than the mass-produced stuff. If you're at the "it's a hobby" phase you really have some impressive skills!

[siulung2005]

Following! I am in for one as well - I need to buy a replacement plate anyway so this is perfect timing!!