How to Make a Carbon Fiber Car Bonnet/Hood - Part 3/3 : Trimming & Assembly 

As a writer of technical manuals and probably one of the few remaining on the planet, I am relieved to see that there are still some companies in the market that are prepared to take the time and trouble to craft excellent "How To" tutorials for those with the need to know about such matters.

In this series we're showing how a *real* carbon fibre part would be made. This is epoxy infused 100% carbon fibre. Sadly, most of what you'll find on the market (and get sold as 'carbon fibre') is mainly fibreglass, often using polyester resin and (horror) chopped strand mat with a single layer of carbon on the surface. The steel original weighed 18kgs, the so-called carbon ones you can buy weigh about 10kg. Our part? - 3.25kg. To the people this is aimed that, that matters a lot.

To those watching that may have missed the comment on the first video, Easy Composites Ltd provided an excellent breakdown of the costs associated with a project like this (I won't be able to answer any questions regarding the following information I'm just copying and pasting it): The exact amount of materials you’ll need will vary depending on the size of your hood so I’ll base this on a bonnet of standard dimensions, you can then scale the quantities up or down depending on whether you hood is larger or smaller than an average 1.5m x 1.2m bonnet. Also, some of the steps (like the gelcoating) are optional and other steps (like the bonding of fasteners) will depend on what you need to bond so I’ve broken these down separately at the end. *Complete List of Materials for Making a Carbon Fibre Bonnet Measuring 1.5m x 1.2m* Mould Making Materials: The outer mould and inner mould will be approximately 1.9m x 1.5m in size. This is about 3sqm per mould. Quantity Product Unit £ Line £ 10kgs Uni-Mould Tooling Gelcoat 52.50 105.00 10kgs Uni-Mould Coupling Coat 46.60 93.20 50kgs Uni-Mould Tooling Resin 114.00 228 15m 80g Chopped Strand Mat 1.70 25.5 14kgs 450g Chopped Strand Mat 2.19 69.66 1 Laminating Roller - 75mm 5.20 5.20 5 3” Laminating Brush 2.00 10.00 100 Nitrile Gloves 4.99 4.99 100g Number 8 Release Wax 6.50 6.50 500ml Easy-Lease Chemical Release 16.50 16.50 330g Yellow Fileting Wax 6.17 6.17 1 roll 50mm Release Breaker Tape 6.95 6.95 TOTAL 577.67 Equipment & Consumables Quantity Product Unit £ Line £ 1 Resin Infusion Starter Kit, 357.00 357.00 With Pump, 5kgs Resin TOTAL 357.00 Materials for the Bonnet Itself For a bonnet measuring 1.5m x 1.2m you would want a surface plies measuring 2m x 1.5m. Based on a an outer skin of 200g carbon, 2mm Soric, 200g carbon this means you'd need 4m of 1.5m wide carbon fibre and 3m of Soric for the outer skin. For the inner skin 2m of 1.5m wide 200g Quantity Product Unit £ Line £ 6m 1.5m Wide 2/2 200g Carbon Fibre 35.00 210.00 200g Carbon Fibre 3m 650g 2/2 Twill Carbon Fibre 25.00 75.00 3m Lantor Soric 2mm 8.14 24.42 1 PT326 Adhesive 400ml Tube 48.41 48.41 TOTAL 357.83 This gives a grand total of £1292.50 (ex VAT) for all of the essential materials and equipment to make the carbon fibre bonnet/hood. Remember than most of the equipment can be re-used forever and that the moulds (the most expensive part) can be used to make hundreds of parts if you wanted to. Optional Equipment & Materials If you want to spray the outer skin with a UV protective gelcoat directly into the mould before infusing then you would need a cup-gun and gelcoat but I would not recommend you do this because it’s an added step of complexity. Instead, I would suggest you infuse straight into the mould and then, if the parts comes out right and you want a UV protective coat, that you just lacquer it afterwards. Quantity Product Unit £ Line £ 1 Gelcoat Spraying Cup Gun 130.50 130.50 2kgs GC50 Polyester Gelcoat 11.75 23.50 TOTAL 154.00 If you don’t have abrasive tools for trimming and finishing the parts then consider: Quantity Product Unit £ Line £ 1 Perma-Grit Sanding Block Small 13.96 13.96 1 Perma-Grit Bosch Jigsaw Blade 3.54 3.54 1 Mirka Combination Pack 19.95 19.95 1 Perma-Grit 32mm Rotary Disc 8.33 8.33 Likewise, if you don’t have a dispenser gun for the adhesive or you need the smaller adhesives to bond fasteners in they are listed here: Quantity Product Unit £ Line £ 1 400ml Adhesive Dispenser Gun 52.50 52.50 1 50ml Adhesive Dispenser Gun 19.95 19.95 1 ET515 Epoxy Adhesive 10.17 10.17 It’s worth remembering that in composites, the most expensive bit (apart from the equipment) is the moulds. In the above list you’re buying a lot of equipment for the first time which you’ll be able to use over and over and you’re also making a mould which, if you wanted to, you could also use over and over. If you only use it to make one part then it pushes the cost of that part right up but having a mould does give you options for making other parts and selling them, or making multiple copies for yourself (rally car use for example!).

We have had customers making large body panels straight off and achieve good results despite no previous composites experience.

This entire series was really incredible. I just recently got interested in how laying Carbon Fiber works and this video answered pretty much every question I could think of about how these sorts of carbon panels are made. The length of the videos just goes to show how detail oriented a project like this is. The more time you spend the better the result. Skip any steps or don't take your time and everything you've done has been wasted. Tons of skill and knowledge involved here, great job. The panel looks absolutely incredible.

It is possible to laminate the hood fastener into the bonnet. You have to consider a number of things, like thickness of laminate, void space between upper and lower skins, access to finish it off, alignment etc. You can always add extra reinforcement if you are worried about strength in that area.

Why did I watch a 3 part series for making a carbon fiber bonnet when I KNOW i'm never going to make one? I guess I just appreciate watching other people laying down carbon fiber for some reason.

And that, ladies and gentlemen, is why carbon fiber body panels are so expensive.

Now I understand why carbon costs so much, a lot of work and detail goes into the making of these things👍

Spectacular series. As a car enthusiast my hobbies have grown to include body work as well as several types of welding. I do believe this will be the next skill set i would like to gain experience in after watching several of the posted videos. Thank you for sharing! !

@easycompositestv these videos are the best. I am sure every FSAE body/aero lead has seen these. They are the best.

All night I've been watching fiberglass videos, and this is the only video I've seen that does Lamination Proper. Thank you for putting my nerves at ease and doing good work.

"and with the information we've given you in this tutorial, so can you." You sir are a master at your craft.

Put it back on to the car. want to see that

I'm waiting for a full double-sided carbon bonnet for my car now and I was quoted 'at least 10-12 weeks' (obviously they're making others too). I can see why it takes a lot of work and expertise.

I've recently looked up how carbon fiber is made and this is the best video and now I can do the same and make carbon fiber in mostly all heavy panels on my car

I just love how high tech this is and then BRICKS

I would never have guessed the amount of labor and sacrificial materials needed. Huge amount of skills and labor on top of the premium materials needed for a good result.

Buying a CF part might be expensive, but after seeing this video I understand that it takes a lot of knowledge and patience. There are many stages in the build that will screw up the whole process if not done perfectly (especially if done by a novice), leading to a very very expensive fail. Thanks for the video, it helped me understand that certain jobs are better left to the professionals.

Actually, this is very easy thing to do, not hard at all. The only thing is that you have to be very patient precise during the whole process of the making. I will try this with smaller parts so i can get used to it and then i will begin with the bigger parts and maybe start designing parts by myself. Thank you for the 3 great video tutorials! :)

Why do I have the feeling that it would take me 3 years to do this?

Me: "Oh man i would love to make my own, they are so expensive." *watch all 3 videos* Me: "You know what, I'll just pay someone to do that and now I understand why they're so expensive."

@Thomas Mulloy From memory, I think the original is around 18kg and this is around 3.5kgs.

Easy Composites 10 years ago: 'This is how you make a CF bonnet' Easy Composites now: 'this is how you 3Dprint a mould to make forged CF, also, here is what each CF weave/technique can withstand *strain gauge comes out*' and 'we have CAD and manufactured a CF mountain bike' love this channel and its progression throughout the years.

One of the best instructional videos I have ever seen.

İn this video I can afford just bricks

I love the one handed hood pickup. This series is over the top.

Just brilliant even i am Never going to need to do this at my old age watching a master craftsman is always a pleasure with amazing results great job mate very well done who does not admire craftsmanship like this?

Watched all 3 part videos. Simply amazing! Thanks for sharing your work and finished piece!

Still far cheaper to do it this way than pay someone to make moulds and then produce a bonnet for you.

This was the best tutorial that I have ever seen. I'm building a 2007 Crown Vic Police Interceptor and replacing the large hood and trunk lid would remove a considerable amount of weight.

It's the best performance I've ever seen on carbon fiber works. Amazing results. Congratulations!

Amazing video! I found this information very fascinating to watch as a fan of carbon fiber car parts!

LOL.. all that 21st century technology and then.... BRICKS

I was planning to make my own DIY carbon fiber hood but after watching this, I might just need to buy 'cause the time and hustle is worth every penny.

I just couldn't hold it after I saw the bricks, otherwise nice tools and work space, and suddenly bricks appear :D Nice work still! I hope I have propper space to make carbon fiber parts for my car(s) some day. Man gotta have hobbies!

wow ive seen less work in open heart surgery videos!!

Yes, if you want to make the part stronger, just add more layers. You can also glass in lengths of metal to strengthen wide areas. The videos you saw people curing their parts in an oven were probably because the CF or glass was prepreg. Prepreg already has resin impregnated in the weave, but it does not have any catalyst. The catalyst makes a chemical reaction that creates heat.. and it's the heat that cures the resin. So when using prepreg, the part must be baked to cure the resin. Cheers!

WOW! brilliant series - very informative - thank you 😍👍

Hi Easy composites. I've understood the techniques you showed in this series for quite some time, but never have I heard or seen it explained so well. This series is a credit to you and your team. Having said that, I do have a couple of questions. Given that the original metal thickness would have been of the order of 0.8mm Question 1. With the thickness of the carbon fibre, the honeycomb layer (sorry, forgot the name), and the next, thin layer this will make the bonnet thickness 'appear' to be quite a bit thicker than the original. I would estimate possibly around 3mm. Not neccessarily a problem if you stop there, but now Question 2. Similar to the above, now for the build up of the underside skin, the layers will be coming out in excess of the original metal thickness. Again possibly around 2+mm Are you are not now bonding these two layers together and assuming or expecting them to match original the bonnet dimensions? I mean, if you were to measure the distance between the two skins of a given part of the original metal bonnet, it would not be the same as the same part on the plastic bonnet. Perhaps this is why you had to add bricks to the underside skin to achieve a suitable join line. Question 3. In view of this, how do you begin to attempt to 'control' each layer thickness so as to avoid this issue? Question 4. Given the strength/rigidity of the mould that you showed, is it not possible that the addition of x number of bricks could end up distorting the bonnet? I would sincerely be interested to hear your reply, and I would like to say that even though you posted this video series nearly 2 years ago, I'm asking the above questions because I see that you replied to another comment from approx' 2 weeks ago. Depending on the answers to the above, I would honestly consider this system for making car body panels. Regards Mark in the UK

Wow this process is amazing! It's so beautiful! Thanks for taking the time to do this. Now I understand why it's so expensive, well worth it. :)

@csgtfaught Yes, definitely. If you know from the start that you're going to clear coat it then you would skip the stage where we use the clear gelcoat (in the second video) because this effectively does the same thing as the lacquer would. It's actually more common to make the part without a gelcoat and then clear coat it afterwards.

Didn't show the bonnet on the car!

Excellent series of videos, I never realized just how much work goes into making a carbon fiber bonnet! Can you tell me how many times (if at all) you can reuse the same mold? i.e. how many bonnets could you make from that one mold? Many Thanks again for a very educational series of videos

You're welcome, I hope we've given your some good tips and ideas and if you needed it the confidence to think that you can take on a large project like this and get success.

A great set of video's that have de-mystified the manufacture of carbon fibre car body panels. Thank you very much Easy Composites Ltd. I'm keeping this short as my mind is racing with ideas as to just what I can do to both with the interior and exterior of my 350Z

just absolutely fascinating skillful and professional work.

Let's see what I need for this project: a hood to sacrifice + all the materials + tools + the guy in the video to do the job. Yeh, that's all.

I'm here in 2018 and loved every second of this tutorial. Thanks guys!

A real pro, amazing work mate!

Well done! Very impressive. I'd really like to attempt a large hood duplication using the same techniques you have applied here. I just need to try and figure out how much material I would need. The problem is that this hood I want to replace is not just big, but it is very heavy. I need to pick up a couple of your kits and do at least one or two smaller projects to perfect my skills first. Thanks for you great video series! Mark

So I watched all 3 tutorials and I'm now curious how much would a project like this cost including all chemicals and tapes used?

I have to say this was an amazing set of videos, seeing a Pro do this is much like watching an artist. I have been wanting to do some carbon fiber projects for a while, I seen on another video when they just brushed on the Epoxy, doing this "Suck" method was ingenious! I also read the forum msg about making an entire car, hell of a first project!

I built some wings for a UAV.. The process is actually kind of fun.. Might want to note that radio waves and CF are not exactly the best of friends (enter learn mode).. A proper mold is important when bonding so that the pieces do not flex while being bonded (weight holding pieces together can distort the mold).. Best video series yet of how to do this in clear and simple terms... great job!

I wanna see the bonnet fitted to the car it was from :( haha this series was amazing. I am so down to do this one day (Y)

I always wanted to buy a car, pull it completely apart and turn it into a Le Mans GTE-style race car, just as a weekend project over a few years. I never knew that you could actually make carbon fiber parts this easily, that's amazing. How long did it take for the entire part? A week?

I am on a very ambitious project to build my own car and start a car manufacturing company. one of the greatest challenges was doing the body parts. either from CF or aluminum these tutorials have been of great help.

fabulous and I will never question again the price of Carbon parts, knowing I long it take and the skills required...well done:)

Great series!

That was awesome. I do suspect you have made it look simpler than it is for a laymen though :)

a great tutorial, a great surface, great craftsmanship. This is really a whole lot of work with some risks especially while infusing and trimming the final product.

the cleanest composite lamination video I've ever seen, very professional good job!

When you do the final trim and edge sanding it appears that you would be sanding right into the joint where the two panels are adhered together. Wouldn't that leave a pretty crappy looking edge? On commercially produced carbon fiber bonnets their edges appear to be rounded or have the carbon fiber wrapped from the top around the bottom piece. Is there another coating or something that further protects the piece?

Now I realize why it is so expensive... Great job

This is why premium vehicles are sooo expensive!! Thanks for this very informative tutorial.

Yes, it is paintable! Scuff the surface lightly with 320grit sand paper first though. I use paint that is designed for use on plastics. I would suggest priming the part with a primer for plastic, and then paint with whatever base color of standard urethane or acrylic you want. Happy glassing!

Easy composites you say...

Such a detailed video and explain so easily that anybody could understand, but I think people will eventually be asking you to make them a bonnet, instead of purchasing every tool that you used.

ASTONISHING! And yes, I think it will be much easier to get a brand-new part rather than making it buy yourself. Buying all the chemicals and carbon fiber itself will cost you around 70% of a new bonnet. And I am absolutely sure that you have to be a well experienced to gain such ASTONISHING quality.

Thank you for a brilliant introduction to CF production. So here's a rookie question: I thought ALL carbon fibre production involved baking of the product to cure it. Were these bonnet parts just left overnight on the bench and they cured?

As he finishes talking about safety precautions, he begins cutting, pulling a 35k RPM sawblade towards his other hand.

Would love to try this, even when the first hood would take two weeks to finish in total. I am amazed by the craftmanship and the detail work (beside the usage of bricks :)) ), because I am a detail freak myself.

Just used thier steps. It works. I did my 1998 Crown-Vic's hood. That shit is light as hell. My hood weighed almost 85lbs. Now only 25. Next up fenders.

I wonder if the cost in materials would equal that of an aftermarket carbon fiber body panel.

1:58 looks like a Stanley kubrick movie lol

Learning something is always good, thanks to easycomposites for explain.

Sand bags better then brick stones maybe?

I guess it would take me less time to go onto the Mars on foot and come back again than it would take me to accomplish this process, lol.

I like how he is telling about the safety without even wearing a gloves 😂

I'll never complain about wet sanding again after watching these 3 videos.

I got carbon splinters just watching this. Cool shit though.

Ohhhh Hi-Tech bricks... 7:00

Nice expert job. I don't understand the dislikes. Surely somebody who disliked the first in the series would stop watching long before now.

Tip: putting painters tape on your bonnet-mount drill points to drill through will help with edge chipping and uneven walls in your drilled holes. :D

I actually watched all 3 parts to see how you bonded the inside and outside together...and you just used bricks.

Why even bother cutting out the center section of the inner part? It would be easier to glue together/Look better (IMHO) and be stronger ...without much added weight.

Its been a long journey, but ive finished watching this. Such a great video, might try this out one day in the near future.

I would get myself small bags filled with sand that will have a soft non scratch outside material. Fantastic video by the way.

Now I know why is so expenssive :p

The way he pronounces adhesive really bothers me but I'm just a stupid American.

hands down one of the best carbon videos around. Who are the 142 morons to have disliked this?? Probably the guys that are pissed off that they'll never be able to afford the material to do this or have the skills to even if they could. lol. One of the best, clear, easy to follow videos for carbon.

A really useful tip - at 8.20 its a good idea to trim the sharp edges off the excess before attempting the close cut to the part edge. It prevents those nasty carbon cuts while concentrating on the important stuff.

I enjoy all your videos. They're really informative. You make it look easy, but that was a crazy amount of work and skill. I'd really like to make a small boat mold, but I have no experience with any of these techniques. The only thing I've ever done is cover a plywood boat with fiberglass using a roller.

Honestly this is great! I wanted to try to make a hood for my car, but the $1500-2000 hoods are expensive! That’s not even counting freight costs 😢 but this shows WHY the craft is so expensive & I respect the people who put the time and effort to make em!

This is a great video that I had to go back and watch it again. I wish I could do this to build a dash for my 2001 dodge truck. The old one broke in 50 pieces like regular glass would do. Thanks again for this video 👍👍👍👍

Damn, i made it to part 3. Awesome video series mate.👍

Makes me want to go buy everything and get started immediately!

This really makes you appreciate full body cars for example like full body carbon fiber koenigseggs

this is really incredible. thanks so much for putting this out there. i feel like i know so much about vacuum bagging that i am going to start bossing other people around on the subject.

There are special tinting pigments available, but generally pigmenting carbon parts rarely works as the black carbon tends to show through most things. A lot of the tinting effects are achieved by spraying the part in a tinted lacquer.