CF inserts and core trim suggestions.

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#1

I’ve been researching here and otherwise, but think the subject could be revisited. I’m making front canards of a buddies design. The individual plates will be 2 layer (0/90,/45) 6k 2x2 twill cf on both sides and .125 Closed cell foam FR2305 core.

How would I best fasten plates together? My first thoughts are drill small holes and use rivets with either painted aluminum or cf L. Is there a insert for foam core holes I can buy in US?

Next question is my plan for edges is cutting at a 45 angle in core edge, and then trim over all design .25in past cores edge. How can I make this look like there is no core or will it look fine with tapered ends?

This will be a wet layup and vac bag. I will have a full step by step once parts finished.

#2

Another view of poster board template.

#3

Well firstly depending on how much pressure and heat there is during manufacturing, you may be able to get away with no chamfered edge.
however, if using pressure to cure, you can just recess foam cores like honeycomb cores, use an edge filler of the appropriate colour or paint it. Body-filler is a simple option.

Im assuming you want to attach the vertical panel on the right hand side of that photo do you? where you are connecting through thickness on one panel to the edge of another?
In this case, (assuming you dont want them bonded together permanently) a simple option is to recess a bit of the core on the edgewise panel and bond in a square nut to which you can screw into. Something like this: http://www.nuttybolts.com/fasteners/images/NSQ%20REG%20SQ%20NUT%20ZINC.jpg
If you’re connecting panels edge to edge it would be different again of course

#4

Loverly design. But why a core? I have wet layup cannards on a uk and Dutch time attack car that’s leading both competitions in the pro classes. And we widend before the last round at silverstone and weekend and we are only just seeing flex. And these are at 150 + down the national straight. And we broke the ta lap record. A correct layup with the right orientation in material will be fine. Don’t need to be messing about with cores and stuff especially with and end plate.

#5

I love practiced advice, thank you. I only chose core as when I made plate without a core it was flimsy as hell. I just realized I’m using 3k twill that is only .009" thick. Would getting some thicker carbon for inside like so help…
6k
Weight per square yd. 10.3oz (340 gsm)
Thickness .024
Construction 10x10

Do maybe 1 layer 3k (.009"), 2 layers 6k (.048" total), and then another layer 3k (.009"). That would put me at .066 thickness roughly.

For fastening I’m thinking of making some L carbon fiber brackets and black rivets to hold assembly together. That way changes to design are more of just filling old holes. If I bond it all together, don’t have that option.

Since you work on time attack vehicles, this is a AE86 with a Lexus 1UZ V8 in it. Does pretty good on speed, but I doubt he can hit 150mph on any tracks around here.

#6

We are off to assen in a few weeks to wrap up that championship. The ae86 sounds like a hoot to drive why a uz over a jz?

Yer you have the option with bolts to swap and change on the fly which is good. Especially adapting to low and high downforce tracks. Keep us updated