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Full Version: Porsche 914 Dash Repair via CFRP Wrapping Process
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dovsky
CFRP stands for Carbon Fiber Reinforced Polymer, which is the technical term for what most people refer to as just simply “carbon fiber”. CFRP is a composite material comprised of the carbon fiber itself (in this case in the form of woven fabric) and a formulated resin compound acting as a plasticizer.

In this thread I’ll be showing step-by-step how we (www.compositedimensions.com) were able not only to repair and save a cracked 914 dash, but to also make it look and feel as if it was originally made from CFRP.

Below are a few photos of the dash prior to the repair.
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STEP 1 – Crack Sealing. We used a 2-part epoxy putty compound to fill and seal each crack. An unlike most polyester-based body fillers, this compound is compatible with the epoxy resin system used in the later steps.
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STEP 2 – Epoxy Based Coat. This base coat provides an ideal black background for the carbon fiber fabric and allows the dash to gain back some of its rigidity at this early stage. After its application, it’s left to reach a “tacky” stage (approx. 4 hours).
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STEP 3 – Making Cutting Templates. Carbon fiber fabric is expensive. This particular fabric is $50 per square meter. In order to minimize material waste, cutting templates is a must. This not only saves material but also provides more accurate placement with minimal seems, and eliminates “bridging” on intricate contoured areas. The fabric itself is a high quality 200 grams/sq. meter 2/2 twill 3K.
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STEP 4 – Carbon Fiber Wrapping (Dry). While taking advantage of the tacky surface on the base coat, and with the aid of a compatible spray adhesive, the various pre-cut carbon fiber pieces are carefully placed into position. Notice that we also wrapped the visible underside areas.
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STEP 5 – Clear Epoxy Resin. Once all the carbon fiber is laid, we applied 3 coats of a specially formulated high viscosity epoxy resin. Minimal sanding in between coats is performed to remove obvious high-spots before allowing the final coat to cure overnight.
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All visible areas on the underside are also addressed.
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STEP 6 – Sanding (Dry & Wet). The dash was sanded dry using 120 grit paper to remove any remaining high-spots before moving on to wet sanding with progressively finer girt paper (240, 400, 800 and 1200), leaving a smooth satin finish at the end. This is by far the longest process step.

Dash after dry-sanding it with coarse 120 grit paper:
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Dash after wet-sanding it with fine 1200 grit paper:
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STEP 7 – Finishing. We applied 2 coats of UV-stable high-gloss lacquer. Once cured we then machined-polished all surfaces to achieve a professional finish.
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The dash is finally done and ready to be installed back.
Project duration: 2.5 weeks including curing & drying times (epoxy resin and lacquer coats).
Total Labor hours: 45 (most of them spent on surface sanding)

I hope you enjoyed this article. All questions are welcome.

Checkout our other products and services at www.compositedimesnions.com along with our growing 914 Carbon Gear parts catalog where you will find sun visors, center consoles, side mirrors, gauge and trim panels.

Dov
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Dov Chartarifsky
CEO – Composite Dimensions
Hameyasdim #62
Zichron Ya'akov
30900, Israel
Tel: +972 (0) 50 4047915
dovsky@bezeqint.net
dov@compositedimensions.com
Andyrew
Awesome process! Thanks for sharing!
Coondog
I would put that on my 914. You guys do great work. Need to put some of your products on my wish list for sure..... smile.gif
Chris Pincetich
drooley.gif beerchug.gif
914_teener
Curious...is a fixture used during the layup process to assure the mounting points don.t move or warp?

Do you have any pics with it installed in a car?

Thanks for sharing
Mikey914
I would assume that the carbon fiber is being used with a resin that allows it to be more flexible (like fiberglass), if so as long as it was relatively flat it should be just fine. All in all looks lik ea high quality product. I wouldn't worry about it cracking in the future as it's basically a "shell"
Darren C
Fitting the ashtray would be awkward as the overlay would make the opening smaller. I doubt it would fit without cutting down the ashtray front and spacing out the steel ashtray support.
Also the dash would be over length which would make it harder to fit between the A pillar trims. The gauge panel too needs all the space the original dash offers.
The overlap of your carbon wrap & resin on the underside would also raise & push out the position of this trim when fitted to the dash frame by the thickness of the resin. This would also cause alignment issues getting the fixing studs (at 90 degrees) to locate in the dash frame.
The wrap on the undersides in the door shut area would also push the knee roll down making that hard to fit back.

For the reasons above, this is why a dash cap is cut short at the ends and stops shy of the gauge panel.



As pretty as it looks....Have you tried fitting this in a car yet?

Trust me on this one. A simple retrim of a dash top with vinyl or leather gives you all these fitment issues, so with carbon and resin your making it larger and heading for a poor fit back in the car with little compression ability that you get with vinyl or leather that makes it just possible to get back in.
dovsky
QUOTE(914_teener @ Feb 2 2016, 06:37 PM) *

Curious...is a fixture used during the layup process to assure the mounting points don.t move or warp?

Do you have any pics with it installed in a car?

Thanks for sharing


No special fixture was used. We only added a single layer of carbon fiber, which is flexible enough not to alter or warp any of the mounting points.
Mikey914
Might want to check the ash tray and the mount in the car. A lot of times the devil is in the details. It may be ok, but I would offer a ashtray cap to match too, otherwise you will have a really shinny nice dash with a chunk missing and an old ashtray there.
dovsky
QUOTE(Darren C @ Feb 2 2016, 06:49 PM) *

Fitting the ashtray would be awkward as the overlay would make the opening smaller. I doubt it would fit without cutting down the ashtray front and spacing out the steel ashtray support.
Also the dash would be over length which would make it harder to fit between the A pillar trims.

For the reasons above, this is why a dash cap is cut short at the ends.

As pretty as it looks....Have you tried fitting this in a car yet?


We've only done one dash, which is now being shipped back to it's owner for fitment. The added thickness is minimal at about ~1mm (CF=0.25mm, resin/lacquer=0.5-0.75mm). In case of any over length/size areas, these can easily be sanded down.
dovsky
QUOTE(Mikey914 @ Feb 2 2016, 06:57 PM) *

Might want to check the ash tray and the mount in the car. A lot of times the devil is in the details. It may be ok, but I would offer a ashtray cap to match too, otherwise you will have a really shinny nice dash with a chunk missing and an old ashtray there.

Good point.
Darren C
I'd wait until you get feedback from the original owner who's tried to fit this back in his car until you promote this service. I'd guess you have a good deal of "development" and adjustments to go before its ready to sell as a viable proposition.

Sending a highly polished stunning looking dash back to the owner and saying sand the finish off where it wont fit back in your car is not a good selling point. Owners want a bolt-in solution.
You'd be better to befriend a local 914 owner and perfect the part to make sure they fit straight out of the box.
dovsky
QUOTE(Darren C @ Feb 2 2016, 07:07 PM) *

I'd wait until you get feedback from the original owner who's tried to fit this back in his car until you promote this service. I'd guess you have a good deal of "development" and adjustments to go before its ready to sell as a viable proposition

There will never be a one-size-fits-all proposition. All vehicles have tolerance variations, specially on these vintage cars. In this case, we put our best effort to save a flimsy worn-out dash, which would otherwise be trashed or discarded. Kudos to the owner for wanting to save his dash. And yes, we will be hearing from him soon.
JeffBowlsby
The last thing anyone would want on any dashboard is a shiny or light colored surface, so I hope it has been prepared as dulled down as possible to minimize reflections and glare that impede vision.

While the CF may be an interesting finish to some, the main reason for a padded dash is safety during a collision. A splintering hard plastic CF material during a collision could add to the injuries sustained in a crash.

Just because it can be done, does not mean its a great idea.
dovsky
QUOTE(Jeff Bowlsby @ Feb 2 2016, 07:20 PM) *

The last thing anyone would want on any dashboard is a shiny or light colored surface, so I hope it has been prepared as dulled down as possible to minimize reflections and glare that impede vision.

While the CF may be an interesting finish to some, the main reason for a padded dash is safety during a collision. A splintering hard plastic CF material during a collision could add to the injuries sustained in a crash.

Just because it can be done, does not mean its a great idea.

CF is an acquired taste not for everyone, especially in a purely cosmetic application like this one. The high-gloss finish was a customer requirement, but it can certainly be dulled down with a satin non-reflective finish if glare is a concern.
dovsky
QUOTE(Coondog @ Feb 2 2016, 06:07 PM) *

I would put that on my 914. You guys do great work. Need to put some of your products on my wish list for sure..... smile.gif

Thanks for the complement, we'll be happy to serve you anytime!
Hank914
QUOTE(dovsky @ Feb 2 2016, 09:02 AM) *

QUOTE(Mikey914 @ Feb 2 2016, 06:57 PM) *

Might want to check the ash tray and the mount in the car. A lot of times the devil is in the details. It may be ok, but I would offer a ashtray cap to match too, otherwise you will have a really shinny nice dash with a chunk missing and an old ashtray there.

Good point.


Or let people DIY match their ashtray, or their custom-cup-holder-in-the-ashtray-slot, or their custom-cell-phone-holder-in-the-ashtray-slot. I could see leaving my cup holder with the 914 logo, or going with the CarbonFiber look. Either would be okay by me.
Justinp71

Looks Great! Two questions- how much is it to do the dash in carbon fiber? And in the pictures on your website, who re-did your gauges with the aluminum brush finish? Those look great too!

dovsky
QUOTE(Justinp71 @ Feb 2 2016, 08:59 PM) *

Looks Great! Two questions- how much is it to do the dash in carbon fiber? And in the pictures on your website, who re-did your gauges with the aluminum brush finish? Those look great too!

To do the entire dash from carbon fiber will be almost cost prohibited because it will first require us to make the tooling (molds) for it using an original sacrificial dash in good condition - and those are not cheep. It will only make sense in a group buy scenario where the cost of the tooling could be absorbed by say 10-15 buyers. And even in such a low production run, the price point will probably be in the $1500-$2000 range leaving very little margin. Some things just don't make good business sense to make.

Regarding the aluminum gauge rings, I bought them from another member (spunone) back in 08. Not sure if he still makes them, but you can try asking him directly.
Justinp71
QUOTE(dovsky @ Feb 2 2016, 11:15 AM) *

QUOTE(Justinp71 @ Feb 2 2016, 08:59 PM) *

Looks Great! Two questions- how much is it to do the dash in carbon fiber? And in the pictures on your website, who re-did your gauges with the aluminum brush finish? Those look great too!

To do the entire dash from carbon fiber will be almost cost prohibited because it will first require us to make the tooling (molds) for it using an original sacrificial dash in good condition - and those are not cheep. It will only make sense in a group buy scenario where the cost of the tooling could be absorbed by say 10-15 buyers. And even in such a low production run, the price point will probably be in the $1500-$2000 range leaving very little margin. Some things just don't make good business sense to make.

Regarding the aluminum gauge rings, I bought them from another member (spunone) back in 08. Not sure if he still makes them, but you can try asking him directly.


Thanks. I just mean whats the cost to wrap it in carbon fiber, like you show above?
Chris914n6
The part that overhangs the gauges is supposed to be flat, not sagging. It's not too bad with this one but it is common. It's something that will need to be addressed if you want happy customers.
dovsky
QUOTE(Justinp71 @ Feb 2 2016, 09:45 PM) *

QUOTE(dovsky @ Feb 2 2016, 11:15 AM) *

QUOTE(Justinp71 @ Feb 2 2016, 08:59 PM) *

Looks Great! Two questions- how much is it to do the dash in carbon fiber? And in the pictures on your website, who re-did your gauges with the aluminum brush finish? Those look great too!

To do the entire dash from carbon fiber will be almost cost prohibited because it will first require us to make the tooling (molds) for it using an original sacrificial dash in good condition - and those are not cheep. It will only make sense in a group buy scenario where the cost of the tooling could be absorbed by say 10-15 buyers. And even in such a low production run, the price point will probably be in the $1500-$2000 range leaving very little margin. Some things just don't make good business sense to make.

Regarding the aluminum gauge rings, I bought them from another member (spunone) back in 08. Not sure if he still makes them, but you can try asking him directly.


Thanks. I just mean whats the cost to wrap it in carbon fiber, like you show above?


$650 + all shipping costs. The cost of shipping the dash here from the US can vary greatly depending on which service is used. The owner of the above dash paid $65 via USPS (took 4 weeks). Return shipping cost is just $50 via Israel Post EMS service (2-3 weeks).
sixnotfour
Looks Great,,
there was a member that was making CF dashes and I had him make 2 for me in fiberglass twill to look like a factory race part... fits great.. and ashtray delete
dovsky
QUOTE(Chris914n6 @ Feb 2 2016, 10:22 PM) *

The part that overhangs the gauges is supposed to be flat, not sagging. It's not too bad with this one but it is common. It's something that will need to be addressed if you want happy customers.

I'm not quite sure what you mean. But to be clear, the CF wrapping will conform to any preexisting contour on the dash. So the dash will need to be in fairly good condition shape-wise in order to be a good candidate for this process. If the dash sags or has any odd undulations or unevenness, this process will not restore the original shape.
Sedonut
I had the opportunity to be the first customer. With something like this I expect to do a little final fitting. It's a custom made part, I'm happy to find someone willing to make it according to my specifications.

I also asked for the shiny finish, against the advice of Dov, the maker. With the attitude the customer is always right he made it according to my request.

The communication has been great, and it has been an absolute pleasure doing business with him.

I can't wait to get my dash.






r_towle
Kind of a silly question, but given these dash pads are pretty weak and easily damaged when off the car, do you have suggestion on packaging the unit to send it halfway around the world safely?
Sedonut
Shipping the core is not a problem, if it picks up another crack or two in transit it will be repaired in the process.

It should be stronger on the return trip. The other advantage is it is light and relatively easy to handle. The gorillas at the shipping companies might not hurt it as bad as something heavy.

If it falls off the truck or the ship sinks, all bets are off.

The process has been perfect so far.
76-914
QUOTE(Sedonut @ Feb 2 2016, 07:41 PM) *

I had the opportunity to be the first customer. With something like this I expect to do a little final fitting. It's a custom made part, I'm happy to find someone willing to make it according to my specifications.

I also asked for the shiny finish, against the advice of Dov, the maker. With the attitude the customer is always right he made it according to my request.

The communication has been great, and it has been an absolute pleasure doing business with him.

I can't wait to get my dash.

Take his advice. That finish will blind you when the sun reflects off it.
Chris914n6
^^ dash mat. easy.
Sedonut
Received my dash safely today. It only took 7 days form the day it was shipped.

Dov was a pleasure to work with and could not have been more professional. Click to view attachment Click to view attachment
3d914
QUOTE(Sedonut @ Feb 11 2016, 09:44 AM) *

Received my dash safely today. It only took 7 days form the day it was shipped.

Dov was a pleasure to work with and could not have been more professional. Click to view attachment Click to view attachment


Perty - be sure to post another once its installed.
fiberglass1inc
What do you do for UV resistance? Most epoxies yellow pretty quickly when exposed to the sun.
fiberglass1inc
Click to view attachment While laying up a carbon part I noticed that the twill fabric resembled the 914 upholstery. I needed a couple more gauges so I made this to hang below the dash.
fiberglass1inc
Installed under dashClick to view attachment
dovsky
QUOTE(Sedonut @ Feb 11 2016, 06:44 PM) *

Received my dash safely today. It only took 7 days form the day it was shipped.

Dov was a pleasure to work with and could not have been more professional. Click to view attachment Click to view attachment



Thank you Tony. It was a real pleasure working with you too. Enjoy your recovered dash and please let me know if you need any support. Looking forward to see some photos once your install it. Dov
dovsky
QUOTE(fiberglass1inc @ Feb 12 2016, 12:56 AM) *

What do you do for UV resistance? Most epoxies yellow pretty quickly when exposed to the sun.


The dash was treated with 3 coats of automotive-grade UV-stable clear coat lacquer. Nevertheless we always recommend to avoid any overexposure to sunlight and to use a windshield cover when the car is parked outside. These common sense steps will prevent the dash from turning yellow overtime just like they will help prevent cracking and discoloration on any vinyl or leather trimmed dash.
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