How to attach fiberglass fenders?

[86930]

For those of you who have used fiberglass fenders, what kind of hardware did you use to bolt them on? It doesn't look like the U-shaped speed nuts used on the steel fenders will work with the thicker fiberglass part, and it seems like it will be difficult to reach the nut to hold it if a standard nut and bolt are used. Any creative solutions?

[jpnovak]

I made 1x2" aluminum plates that were drilled and tapped. This distributes the load similar to what the factory clips did. Offer up the fenders, mark the holes, drill the fender, use bolts, nuts and backing plates to attach fenders.

[A horse with no name]

Originally Posted by 86930

For those of you who have used fiberglass fenders, what kind of hardware did you use to bolt them on? It doesn't look like the U-shaped speed nuts used on the steel fenders will work with the thicker fiberglass part, and it seems like it will be difficult to reach the nut to hold it if a standard nut and bolt are used. Any creative solutions?

Hi...3M 08274 is a excellent product for what you want to do. Actually an amazing adhesive to say the least. Once applied, clamped and cured your fenders 'will not' fall off.

Description
A high performance two component epoxy adhesive with excellent sag resistance. Used to bond SMC and FRP (traditional fiberglass) body panels to each other and to metal frames. 3M™ Automix™ Truck Line SMC/Fiberglass Adhesive - PN08282, 3M™ Automix™ Mixing Nozzle - PN081933M 08116 panel adhesive:

Companies such as 'Freightliner Trucks use it - E.G. - Bonding their roofs to metal cabs. - Automotive shops are using it for skins rather than welding...

Its about $75. ? plus you will need this dual catridge gun - $50?....
://www.autobodytoolmart.com/3m-manual-200-ml-cartridge-applicator-gun-08571-p-15298.aspx

[mreid]

I certainly wouldn't use a panel adhesive!

How about these:

McMaster-Carr

[Flieger]

I use Dzus fasteners - a.k.a. quarter-turns.


911S rear chassis_ 019 by Max_911S_fahrer, on Flickr

911S rear chassis_ 018 by Max_911S_fahrer, on Flickr

911S rear chassis_ 017 by Max_911S_fahrer, on Flickr

911S rear chassis_ 012 by Max_911S_fahrer, on Flickr

911S rear chassis_ 011 by Max_911S_fahrer, on Flickr

[86930]

Originally Posted by jpnovak

I made 1x2" aluminum plates that were drilled and tapped. This distributes the load similar to what the factory clips did. Offer up the fenders, mark the holes, drill the fender, use bolts, nuts and backing plates to attach fenders.

Interesting idea...tapping the aluminum plate makes sense, but did you use a nut as well? is it really necessary to use both? If you use a nut on top of the tapped plate, what is the point of tapping the aluminum plate at all? (rather than just drilling a hole and using the aluminum plate like a big washer to distribute the load)

I was really hoping there would be a way to fasten without having to hold the nut while tightening the bolt inside the trunk. Some of the nuts would be in really difficult to reach spots.

[86930]

Originally Posted by A horse with no name

Hi...3M 08274 is a excellent product for what you want to do. Actually an amazing adhesive to say the least. Once applied, clamped and cured your fenders 'will not' fall off.

Just to clarify, I am looking to install the front fenders. I suspect this advice is for fender flares? You aren't suggesting to "glue" on the front fenders, are you?

[A horse with no name]

I'm sorry Larry... I never read your question properly...I was referring to fender flares.

If you don't mind my 2 cents worth...I suggest for you to make a few of the plates out of metal (steel) the size that 'jpnovak' suggested so that you could...

1st - Spot weld the nut to the plate.
2nd - In those hard to get at places... Drill 3-4 small 3/8? holes on the inner fender wells and plug weld the plates to them.
3.- If you don't have a welder do the same but use something such as JB WELD or say Belzona 1111 (Super Metal) ...You would then have no trouble bolting your fenders on in these hard to get at areas.


Side Bar-Re adhesives for fender flares.
Many Porsche aftermarket fender flares- metal and fiberglass- are held on by adhesives such as 3M's...Example _ 'rattlsnak' who is a PP registered poster since 2000 made this post:

Quote: "done both a few times, other than cost, no real difference if you use good glue, (3M). I glued some onto my SC @ 10 years ago, and you can still pick the car up from the outside of the flare lip with no seam signs. With today's glues, gluing is fine."