Attaching conduit to fiberglass. Best adhesive or method?

Need input from the hive experience:

I am wiring up the 1920 Model  A hot rod. It is a fiberglass car, so my welder is not much help in this project.

. I need to create some sort of conduit up under the dash and against the firewall to run wires.

I would rather not drill through the firewall as it will be seen on the engine side.

First thought is to get a fiberglass repair kit and use it to attach pvc tube in place. I think that will work.

Was wondering if there is an adhesive that would be less mess for the job? Basically a 3" long 1.5" pvc tube stuck on a vertical surface/firewall.  I will probably use the same stuff to attach the cable tie hold-downs throughout the rest of the project if there is a suitable adhesive. Hoping that the solution can be found at Home Depot rather than mail order.

Would any of the common products like gorilla glue or liquid nails be up to this task? No experience with either product.

Can you roll a piece of fiberglass mat over your conduit and glass it in to the firewall?  This will keep you from having to use fasteners.  I would assume some kind of 2-part epoxy for gluing stand-offs to fiberglass.  I'm sure people that actually know what they're talking about will chime in.  :)

Can't you use conduit C-clamps and bond those to the fiberglass? Probably with a large glop of JB Weld?

I would just bond the pvc tube to the tube with fibre glass mat and resin. Be sure to rough up the area being bonded.

3m 08115. It's what that stuff is designed for. Bonding a variety of materials to each other. 

Used properly, the stuff works *fantastic*. 

https://www.3m.com/3M/en_LB/p/d/v000056367/

I keep epoxy around for just this kind of thing.

Polyester resin (the kind that comes with a fibergass repair kit) WILL NOT bond to PVC.  I know this because I often use PVC as a fiberglass mold and it pops right off.  You need an epoxy or something like 08115

is there some kind of Velcro that has that super 3M glue, 

asking for a friend :)

Dont need it to attach to the PVC so much as the plan was to used the small fiberglass repair kit to make "straps" to the firewall.

I am aware of panel bond, but was under the impression that intro to this technology was going to be in the $100s of dollars by the time I bought the special dispensing gun and a two part cartridge. Doing this build as a charity case to help a friend, so the less $$$ I lose the better.

I have a few cartridges of PL adhesive in the shop. Might go put a few dollops on the backside of some parts and see how well it adhered; they sure do sell the stuff in the marketing lit.

If smooth surfaces, why not 3m trim tape?

A tube of Loctite PL from Home Depot and you're golden. It's a $6 solution in a caulk tube. 
 

Just run a bead on each edge. Done. 

Loctite 9309 or 9394

That's how you attach two not-metal things in aircraft.  Comes in smaller quantities pre-measured to mix together. Just hit the two items with some abrasive for grip, clean it well, and it'll never come apart:

https://skygeek.com/henkel-hysol-ea-9309-na-25-gram-ez-pack-as9355008.html

NOHOME said:

Dont need it to attach to the PVC so much as the plan was to used the small fiberglass repair kit to make "straps" to the firewall.

I am aware of panel bond, but was under the impression that intro to this technology was going to be in the $100s of dollars by the time I bought the special dispensing gun and a two part cartridge. Doing this build as a charity case to help a friend, so the less $$$ I lose the better.

I have a few cartridges of PL adhesive in the shop. Might go put a few dollops on the backside of some parts and see how well it adhered; they sure do sell the stuff in the marketing lit.

 

gotcha.  I like SV reX's idea of the Loctite PL.  Set it and forget it.  Hold it in place with some tape until it cures

NOHOME said:

I am aware of panel bond, but was under the impression that intro to this technology was going to be in the $100s of dollars by the time I bought the special dispensing gun and a two part cartridge. Doing this build as a charity case to help a friend, so the less $$$ I lose the better.

Nope. The applicator gun is about $50-$70, and the cartridge is like $45, retail.  It's well worth it, considering it also opens up being able to use *quite* a few other great products for things like heavy bodied seam sealers,  dedicated plastic repair,  etc.

And there she is bent to fit in a nice recess will a good dollop of adhesive. Cut a few speed holes cause why not? And some header paint, caus it looked like black PVC conduit, and now it looks like PVC conduit with silver paint! 

Guess I also need to get on my back and paint the metal cross-bar behind the dash as it looks a bit rusty. That will never do.