Bonding Front Carbon Cycle Wings

[Guest]

I'm coming towards the end of my build, and am going to be bonding the front cycle wings into place.

 

There are two options (I believe):-

1. Bond Bighead Fasteners to wings, then tie wrap these to the wing stays?

Do you drill through the wing stays to secure the tie wrap?

2. Derek at CC suggested the factory bond the wings directly to the wing stays.

 

Anyone done either of these, and if so can you provide pro's and con's...

 

Any advice would be appreciated.

Thanks.

[Domus]

I used the Big Head system, no drilling required. Every year at service I remove the wing to clean and give better access to the brakes. Then fit new cable ties. I have heard that Caterham bond to the powder coat and these have sometimes failed.

 

I think the Big Head system is simple and more user friendly and more elegant than bolts.

[Guest]

this is the fixing method I was thinking of taking.

Can you confirm one thing though... With the big head and cable tie fastening does wing slide around on the wing stay under aero / lateral load due to the cable ties slipping on the wing stay?

 

Edited by - Roadracer1977 on 19 Mar 2014 10:23:37

[Frying Pan]

Agree that Bigheads are a better solution than bonding directly, as you can easily remove them is needed.

 

I did manage to lose a cycle wing even with Bigheads (thread here) though as the bond failed - I probably didn't use enough Sikaflex - Make sure it oozes through the holes in the Bighead bases.

 

All ended well though, as I bought some lovely Ultimate Carbon replacements 😬

[Domus]

I find that I can push the wings a little left and right to centralise them over the tyre but can detect no movement in driving, certainly don't stare at them on the move as i find there is enough going on through the windscreen.

[Guest]

ok that's what I thought, but my concern was more about the wing rubbing on the tyre / catching.

[CharlesElliott]

I've done both a number of times.

 

Bigheads have the advantage of being removable and for a road car, this is what I would do. Personally, I would be less worried about the Bigheads pulling off, and more worried about the cable ties wearing through with vibration. Trick is to use a couple on each Bighead and check them every few months. You don't need to drill the wingstays.

 

Bonding directly to the wings takes out all the worry, assuming you use the right bonding stuff and prepare the surfaces. I've now done this because on a race car, having a wing coming off/rubbing a tyre can really destroy your chances in the race!

[Guest]

OK cheers - any recommendations for getting everything aligned properly prior to bonding?

[BigCol]

I know it's contrary to what you're likely to do but Derek told me:

We use Terostat to bond the wings, when using it make sure you take the powder coating off the wing stays and rough up under the wing. Don't use too much to initially bond the wing. When it has stuck put some more on in the infill's using a wet gloved finger to smooth it down.

 

I used a piece of wood whose thickness was fortunately exactly half the difference between the tyres' and wings' widths. By laying it on the front face of the wheel/tyre, I lined the wings edge withe the wood's edge. Repeating on the rear face meant I was happy the wing was straight and central.

 

For fore/aft, a length of 2x1 vertically against the front of the tyre, a spirt level to make sure it was plumb and another chunk of wood between the front wing edge on the 2x1 made sure of clearance and consistency!

 

For me it was very much a variation in the "measure twice, cut once" theme... I treble-checked twice!

[UremaW]

Definitely bond directly to the wing stays, having first stripped off the powdercoat from the top, roughed up both contact surfaces and cleaned them with nail varnish remover or similar.

 

Apply plenty of Sikaflex to the wings, line them up properly over the wheels, then tape the wings to the wheels to hold them tight for 24 hours until cured.

 

Then apply more sikaflex so that it coats the wingstay completely. Leave another 24 hours to set.

 

Worked perfectly for my original wings, and only took 10 minutes with a stanley knife to remove when i went to fit my new carbon wings last weekend.

 

Some pictures are available in the build diary - Blog

[Grubbster]

Bigheads, easier, quicker, allows for some side to side adjustment should you need it, easy to remove wings if you ever need to. Thoroughly clean everything first, stick with sika 292 or bigheads own acrylic FS. Full details of how on my blog. If you put a foam strip along the top of the wing stays the wings won't move of their own accord.

[Z3MCJez]

Steve - I'm stunned you didn't break any big heads in a year with Edna. Maybe the batch I had wasn't up to it, but I would never use them again on a track car.

 

Jez

[Grubbster]

Quoting Z3MCJez: 

Steve - I'm stunned you didn't break any big heads in a year with Edna. Maybe the batch I had wasn't up to it, but I would never use them again on a track car.

 

Jez

 

Hi Jez, I did actually have 2 breakages during the year but not catastrophic as only 1 at a time so no harm done. I put it down to a bad batch (the weld went) so just replaced and carried on with no further issues. I suppose if I was that worried I'd just fit an extra pair per wing but to be honest it never concerned me. I've been using them on my other car for 10 years and 30,000 miles with no problems at all and it has a much harder life than Edna ever did.

[CharlesElliott]

If you use Bigheads you can move them side to side anyway.

 

If you bond them, then I would start but putting a thick line of bond on the wingstay, and then drop on the wing and position as required before then securing to set.....

[Dave Rayner]

Can confirm bigheads are the way to go, I bonded the bigheads to the underside of carbon wings with carbon ribbon this giving belt and braces strength.