Need some help with an Overlay on 2x4 wood

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#1

I haven’t been on these boards much. I got out of the composites world several years ago. I sold off all my resins, vacuum pumps and miscellaneous hardware.
I kept my 300+yards of 5harness Carbon Fiber though…

:smiley:

I want to overlay some Carbon Fiber ontop of some 2x4 piece of wood. These wood piece will go into the truck bed of my hot rod 1938 Ford Pickup. I have never wrapped wood so I have some questions:

  1. What type of wood should I buy? Pressure Treated or not? Is plain jane cheap wood acceptable?

  2. How should I prepare the wood surface? Seal it? If so, with what? Sand it? What grit?

  3. What type of resin should I use? I want to avoid epoxy resin if I can.

  4. How should I wrap the wood with the Carbon Fiber? Single flat piece only on top? A piece that lays on top but wraps down both sides? A single piece that wraps compeltely around the 2x4?

The current wood in the bed is some low grade stuff that was painted black. On really hot days the sap from inside the wood seeps out. I think I will have to pull it out and completely replace it with new wood.

The epoxy resin I use to use for my products was always a pain to get the mix ratio perfect. I scrapped so many parts because I didn’t weigh thigns accurately.

I don’t want to spend a ton of extra money to get this project completed. So, if I can use the current wood I have and simply sand it and fill in the knots and broken spots with wood filler, that would be cool.

Thoughts and advice?

#2

No one can help a brother out?

#3

Hey man, by no means am I an expert but I would be worried about moisture being trapped in the wood. Cool idea for the truck bed though, Does 38 have metal strips in between the boards like later trucks? Does the fiber have to fold over an edge so the strips (if there is any) sit flush to the top of the wood? If so it may be hard to overlay that and expect a “hard edge” when finished without vac’ing. Im sure more will chime in here soon though…Good luck!

OH and lets see some pics of the rod!

nolan

#4

use
straight wood
epoxy
shrink tubing from uline

seal the wood first
lay material on wet
slide tube on and shrink to fit
work from one end to other removing excess resin and air
remove plastic when cured

#5

The metal strips are all add on to make the bed look nicer. It has nothing to do with the year of the truck.

The metal strips will fit ontop of the wood, they do not have to sit flush. They are only used to cover the gaps between the wood pieces. I will probably add these after I finish with the CF.

I am at work and can’t show off too much. I ahve since changed to the wheels to Chrome Cragar SS. 10in wide in rear and 6in wide up front. Not as nostaglic but way better looking.

I will definitely seal the wood. I have read other people saying that when I searched.

Why do you say I should use the Epoxy resin?
I was kind of trying to avoid that. But I am use to working with Epoxies and can make it happen.

Also, I was considering on laying a bit of resin onto the wood letting it tack, then putting the dry fabric ontop of that, Then wet it all out. Why do you suggest to wet out the fabric before I lay it on the wood?

The Uline shrink tubing is an interesting concept that I have never heard of.
They said that the bags shrink 40-50% because I am doing a 2 x 4 I would probably need a 6-7inch wide bag to account for the 2inch tall wood.

Would you agree?
Do you suggest I buy the thicker stuff or the thing stuff?

Shrinks with a heat gun.
Here is a link to the shrink tubing for anyone else interested:
http://www.uline.com/BL_2406/Shrink-Tubing

#6

suggested epoxy to limit chemical reactions with the shrink wrap

i guess it makes no differance if you wet it on or off the form might be easier to wet it on the form. there is a part i make with tubular braid and prefer to have the fabric wet and squeezed out prior to setting in place

#7

If you are going to use sw why not use the carbon sleeves from soller
http://www.solarcomposites.com/composites/carbon%20fiber%20sleeves.html

#8

Why not just form 2x4 carbon sleeves yourself and get rid of the inner core? I think it would be fairly easy to wrap waxed and PVA’d piece of aluminum tubing and bang it out when cured. Of course this would only be for show and to haul groceries, but I don’t see you hauling 3T of stone daily in that truck either. Just a thought.

#9

I was thinking along the same lines. Take a 2x4 aluminum extrusion square tube and grind a slight draft angle from one end to the other and use it as a wrapping mandrel. You’d end up with very consistent parts and they could be as strong as you wish due to laminate schedule choices.

Worse case tool…prep the best and straightest wood form. Sand and seal it with wax and CF wrap. Then wrap ‘stretch wrap’ around it to pull tight.( The packing type…comes in many widths).

#10

I use the truck as a truck. I drive with mountain bikes in the back. I haul around car parts such as wheels, tires, fenders, trunk lids and hoods (STEEL stuff, not CF stuff).
It needs to be wood.

My concern is ensuring that the CF/resin attaches to the wood nice and strong.

When i seal the wood, can I sand that? What grit should I use to sand? the wood to prep it for the resin.

#11

Is there anymore information I need before I start this project?

I am mostly concerned with sealing the wood and preping it for the layout.

#12

Strange…my post for this did not post.

Anyway, I was just saying that the wood will be sealed with the resin (first coat) that you lay down. I would have all your cloth pre-cut to size and laying out ready to flip/roll onto the wet wood.

A large sheet of thick plastic to encompass the full length might help to keep tension on the cloth til it kicks.

Having a nail driven into each end would be helpful to rest on two sawhorses for rotation and handling/moving/drying.

Once unwrapped…another round of sanding and resin should finish it up before it is sanded one last time and clearcoated for UV protection.

Just for the record…all the uses for your truck could have still been used on top of an all composite tube if done right.