Making a carbon fiber airbox - input appreciated

[dsfnctn]

I have build many variations of the resonance flap airbox. this version was resin infused with a male part. see in the picture the advancing line of resin as it gets drawn across the part under vacuum. very cool to watch.

[dsfnctn]

How did you manage the seams, lap joints?

started out taping the seams then with the infusion in an attempt to cut down the cost went to just bonding with flanges

[Reiver]

Originally Posted by dsfnctn

Welcome to Rothsport Racing - Engine Products
K&N

Yes, they are made for (originally) racing and racing lumps are rebuilt often.
I know what passes thru K&N even if washed/oiled per sched...in the Az dry countryside so much dust/dirt came thru a K&N it would clog the idle jets on my carbs to the point it would not run and simply stall out.....you could scoop the grime out on your fingers.
Replaced with a paper element and have never had that issue and the carbs are clean.
K&N sucks in fine particles and if you are good with that ok.

[Reiver]

Wish list...carbon fiber CIS airbox.

[robcf]

Originally Posted by dsfnctn

How did you manage the seams, lap joints?

started out taping the seams then with the infusion in an attempt to cut down the cost went to just bonding with flanges[/img]

Thanks for the feedback, very detailed! It looks like your also bonding aluminum flanges to the manifold for the rubber couplers. Did ever consider building these features into the the manifold itself (there appears to be sufficient draft) or does the geometry make it not possible i.e stepping up to the larger OD and maintaining the ID?

I have a friend of a friend making skiffs using the resin infusion technique. He has much better control of the fibre to resin ratio, reducing mass and cost, increasing the strength of the boat. It did take some time to identify the resin feeds and vac locations.

Thanks for sharing.

[dsfnctn]

Originally Posted by robcf

Thanks for the feedback, very detailed! It looks like your also bonding aluminum flanges to the manifold for the rubber couplers. Did ever consider building these features into the the manifold itself (there appears to be sufficient draft) or does the geometry make it not possible i.e stepping up to the larger OD and maintaining the ID?

I have a friend of a friend making skiffs using the resin infusion technique. He has much better control of the fibre to resin ratio, reducing mass and cost, increasing the strength of the boat. It did take some time to identify the resin feeds and vac locations.

Thanks for sharing.

When I started to make the 997 GT3 airbox I did incorporate building the coupler nipple into the ends of the halves

[dsfnctn]

center section

[JohnJL]

Not to break up the vacuum-layup pornfest, but I have a few open questions on constructing a simple box from CF panels, elbow and flanges.

The pics above have certainly motivated me to make mine look as nice as possible, thats for sure. I wont be matching that level of proficiency though.

A few questions;
- would love to see some somple boxes, for intake or other purposes
- I am planning to cut the straight edges with either a table tilesaw with a smooth diamond blade, or my tablesaw with 100 teeth.
- Then straightening/finishing the edges with fine paper on a straight sanding block
- Using L-section cf angle to reinforce the corners. I would put the angle on the outside if I cant get the edges perfect, otherwise the angles bonded on the inside of the corners?
- Hysol 120e as a recommended bonding agent?
- Rough up the gloss panels at the bonding surfaces?
- Anyone use dzuz fasteners with CF? I need a way to "sandwich" the filter between the main box body and the intake piece. What have people done? I usually use rivets to fasten the dzus springs but I dont think CF likes being riveted.

Love the pics and help. And yes, I am listening. I may toss the K&N...

[JohnJL]

I have some spare fancy-dancy titanium 5mm bolts, any recommendations for 5mm captive nuts or threaded plates made to be bonded to CF or fiberglass panels at each corner instead of dzus fasteners? A quick flick through aircraft spruce didnt have what I think I am looking for?

[robcf]

Originally Posted by dsfnctn

When I started to make the 997 GT3 airbox I did incorporate building the coupler nipple into the ends of the halves

I imagine the section through coupler nipple inner diameter isnt constant, it follows the outside profile?

BTW how did you lay up the centre section, is there a foam core to fill out the heavier sections?

@JohnJL - why do you plan on using plat CF panels, the advantage of using composites over sheet metal is that you are able to create a unique form.
I have used dzus fasteners with carbon fibre and it rivit's fine as long as you us a large head or backing plate to distribute the force.
However if you shall add an insert you'll need to use something which will not crush the CF, in boat building ply is often used at hard points.

Perhaps dsfnctn can provide us with some images of threaded inserts and attachment points.

[dsfnctn]

This is a cheat sheet that I made to show a product line that I use in some of my builds. http://clickbond.com/
They are very well thought out. I like the nutserts with the rubber holding devices. They are cool because the nut is captive in the plate with a clip that allows it to float and also replace if buggered.You just dril the hole and the rubber tube holds it in place until the glue drys ,then you yank the rubber. also the ones pictured with the holdig devices have double backed tape to hold in place and more important when they are designed for the exact amount of squeeze out glue. I have used rivits , rivnuts etc what ever it takes I find my guys bugger riv nuts when they hurry and don't have the hole exact they strip real easy.

The rubber coupler ends on the 997 part are made by whipping the ends with uni directional carbon and then when it starts to cure put the rubber coupler on and it makes the imprint . You get that?
foam core radius between tubes

[robcf]

Those click bond fasteners are very cool, certainly simplify fastener installation. Thanks I forwarding them to my bud.

Regarding the coupler ends, assuming your using a male mold as shown before, you are locally building up the end of the tube with uni and then pushing the rubber coupler on to make the imprint. You may also be doing this once the two halves of the mold are bonded together and then completing this process.

Would you mind sharing images of the 997 intake molds?