Hello and welcome to this Easy Composites video tutorial.
In this series which is probably the most ambitious we'll ever take on we're going to
be answering the question that we get asked more often than any other, which is how to
make you're own carbon fibre vehicle panels like this car bonnet that you see here.
In the tutorial we're going to be showing you every single step along the way including
making the mould, making the parts, bonding the parts together, trimming and finishing
to enable you to make your own incredibly light, incredibly strong perfectly finished
carbon fibre panels.
We really hope you enjoy it.
The first step in our process is to take this original steel bonnet which we're using as
our pattern.
We're going to add barriers all the way around the outside of it so that when we make our
mould we actually created a mould with a flange on, and that flange will add stiffness to
the mould and it will also give us plenty of opportunity to position the bagging consumables
and things for the resin process.
Before we actually apply any barriers to this part we're just going to take the opportunity
to put down a full background layer of release agent.
We're using Easy Lease which is a chemical release agent and of cause this is what's
going to stop the gel coat from sticking to the part but while we've got the bonnet in
this state it's much easier to ensure that we've got everywhere covered and then we'll
probably do another application later on.
Making barriers can be tricky.
The technique that we've developed is to use corrugated signboard for the barriers themselves
and the bond those to the underside of the part using hot melt glue.
So the first thing to do is to use masking tape to actually make a template around the
edge of the part and then we'll transfer that onto the signboard and cut the barriers themselves.
So with the masking tape all the way around the edge of the part it's a case of just marking
up where we're actually going to make the barrier pieces in separate sections and we
also at the same time just draw on the angle that we're going to cut the barrier sections
at and finally number them so we can identify them.
So we're going to have a cut line here and a cut line coming off at this angle here.
Then this will all be one piece and we'll have cut lines on the barrier about there.
The masking tape comes off the part extremely easily.
So we're just going to start it off and then cut it into the parts that we've identified,
being careful not to rip the tape.
So we're transferring this line here onto the board.
We know the angles that we want to make the barriers at.
Once we've marked out all these templates we're just going to cut them out with a sharp
knife and then position them around the outside of
the part.
we're working on the underside of the bonnet now where we're going to be positioning this
barrier.
Now the way we're going to do that is we're going to apply masking tape to the edge on
the underside of the bonnet here and then we're going to be using hot melt glue on the
masking tape and then on the barrier.
the reason for the masking tape is so that this barrier is quite easy to remove when
we're done with the process.
So we can get started with that with the masking tape.
We've got masking tape all the way along this top edge so now it's time to use hot melt
glue gun we're going to just put a bead of glue all the way along the top edge and then
stick the barrier to it.
We've now flipped this bonnet over just before we do the wax we're actually going to use
a release tape to actually just seal these joins, or a breaker tape and that's just going
to prevent again any of the gel coat from running down into the gap.
So we just take the tape and tape the seam and because it's a release tape the resin
and the gel coat won't stick to it.
So the next step is to us a yellow filleting wax to actually create a bead all the way
around the edge between the bonnet onto the flange and what that will do is stops the
gel coat from running under and locking in and also gives us a nice smooth transition
so that when we've got the mould the parts themselves are going to release nicely and
they're not going to get caught up or mechanically locked on this edge.
So we've put the filleting wax all the way around the outside now and you can see from
this close up what we want to do is always be sure that when you put the wax down you've
got what's called a draft angle and that's going to mean that when we remove the part
of separate the part and the mould that there's not going to be a mechanically lock.
We're now ready to put the proper coat of release agent onto the bonnet and we're going
to apply two coats of the Easy Lease all the way over the surface of the panel.
Now the filleting wax doesn't requite a release agent and in fact will actually get dragged
off by the release agent if we're not careful so we're not going to apply any release agent
to the wax.
We are going to apply the release agent onto the barrier itself just in case there's any
contamination.
It is made from polypropylene so it shouldn't stick but just in case it does we're going
to give it a coat over as well.
We've now left this a good half an hour to fully dry off and we're actually going to
apply two coats of wax all the way over the top of this the steel bonnet part.
Now usually we wouldn't use a wax on top of a release agent.
A chemical release agent generally works on its own however in the case of going from
a pattern to the mould itself we want to be absolutely sure that we're not going to have
any problems with the release and so having the chemical release agent and the wax although
it's a slightly unusual combination is going to ensure that we do have no release problems.
We're now buffing off the wax having left it about five or ten minutes and you just
really want the lightest possible pressure when you're doing this just using a micro
fibre cloth here and just skimming over the surface and you can see the shine start to
emerge.
Right so we've now left the wax to fully harden off which is roundabout half an hour or something
like that and so it's actually time to make the mould itself.
So we're going to be using a very versatile tooling system called Uni-Mould and the Uni-Mould
system comprises a tooling gel coat which is a vinylester tooling coat.
Now the reason we're using vinylester is that that's actually compatible with polyester
resin, vinylester resin but most importantly for us epoxy resin and it will guarantee an
excellent release of the parts out of the mould which you wouldn't get with a normal
polyester gel coat.
The Uni-Mould system then uses a coupling coat which is reinforced coupling coat we
actually add a lightweight chopped strand mat in with that which forms the connection
between the tooling gel and then the tooling resin itself.
Applying the gel coat now we can do this in either two thin coats or one thicker coat.
We'd be targeting in a single thick coat of a roundabout 0.8 mm.
Now for a bonnet this size we're looking at mixing up a roundabout 700 grams of gel coat
if you mix up too little and you come up short you can always mix up some more.
We're using normal MEKP catalyst and a ratio of about 1.5 to 2 percent.
So for 700 grams of the gel coat that would obviously be 14 grams at 2 percent of the
catalyst.
Applying the gel coat is totally straightforward covering it and we're going for that approximately
1 mm which is a reasonably thick application.
We've now allowed this gel coat to cure to the right point.
It's certainly very much firmed up but it's still got a very slight level of tack which
is the right point for a gel coat.
So in the Un-Mould system it's now time to add the coupling coat.
As we say we've got a light chopped strand mat, we're using a 225 gram here.
This is really as heavy as you would want to go at the coupling coat stage, you could
go lighter and we're going to be wetting this through with the coupling coat.
Again this is catalysed at a ratio of about 1.5 to 2 percent we're going to be catalysing
it about 2 percent and we're going to use a full kilo on this layer.
When the coupling coat has been fully catalysed it does actually change to a darker colour
so you can tell it's ready to go.
Now when you're working with he coupling coat it's just like any chopped strand laminating
so you apply the resin to the part first and then drop the glass mat down onto the resin
and then wet it through from above.
The light chopped strand provides reinforcement at this early stage but because its a light
mat it's very easy to get it down into the contours of a mould which ensures that you're
not going to have any voids between the gel coat and the main tooling reinforcement and
the coupling coat itself chemically is designed to act as an interface between this vinylester
tooling gel coat and the tooling resin itself.
We've now allowed this coupling coat to cure in our case its taken around three hours and
it's very much firm to the touch but it got a slight tack and that's the right point for
us to go on with the main reinforcement.
Now because we're using the Uni-Mould tooling system we're going to be putting down all
of the reinforcement and the resin in one hit.
The Uni-Mould tooling resin is a filled resin system so it's very important to thoroughly
mix up the contents and we'll also give it a quick stir to make sure that any sediment
or fillers are thoroughly mixed in to the resin.
With the resin catalysed at between 1 and 2 percent, we've used 2 percent because it's
only a small mould we're then going to apply the resin all the way over the surface and
start building up this chopped strand mat.
So we want to work reasonably quickly and get it all down in one hit.
We've now allowed this to cure fully overnight as you can see the colour of the mould has
changed to a lighter shade indicating that the exotherm has taken place and so we're
going to turn the mould over and without removing the bonnet we're going to look at making the
moulding for the inner skin.
Okay so we're now going to remove the temporary barriers that we put in place.
And you can see the why we signboard its released perfectly from the tooling gel coat.
we're going to be using the flange from the upper mould as the flange for the lower mould
and so what we're going to do is leave most of this filleting wax in place but we're just
going to ensure that it's nice and smooth so that its acts again as a fillet between
the flange and the inner mould that we're going to make.
So we're looking at the underside of the bonnet now.
We've got lots of holes as you can see that have been cut out, die stamped out of this
inner skin we need to blank all of these of which we'll be using release tape for and
we've also got these studs here that were for the hinge mechanism and the latch at the
front.
Now because we're happy to sacrifice the bonnet in this case we're going to grind these off
and again grind the latch mechanism off.
If you didn't want to sacrifice the bonnet and you want to keep it useable then you could
blank these off using plasticize or something similar and then make the mould around them
but for simplicity we're just going to grind them off.
So applying the release tape to mask off these holes on the underside of the bonnet.
We just pull the tape tight over the hole and press it down firmly.
So where we've ground off this latch mechanism we're going to tape all the way over this
using the release tape.
And the tape should be sufficiently strong that we won't need any other reinforcement
over that area.
So we're applying the Easy Lease chemical release agent all the way over the surface
of the inside of this part and very importantly this time round on the flanges as well.
We'll be applying two applications of the chemical release agent and then we'll be following
up with two coats of wax making sure on this occasion that we thoroughly wax the flange.
Where you can see the upper moulding meeting the lower moulding and we've got this gap
here we need to thoroughly fill that with the wax fillet to prevent the tooling coat
from running under there and sticking.
So we just put in a large bead of wax and then smooth it out in just the way we've been
doing elsewhere.
So if we just take a quick tour now of what we've done before we put the gel coat on.
We've got release tape over all of the catch mechanisms we've got any interior holes we've
filled with release tape and again we've cut those to be nice and neat.
On these areas where we've got a bit of undercut on the actual steel of the bonnet we've completely
filled that with filleting wax as we did with this awkward corner.
And you can also see how we finished that middle edge.
Okay so we've just mixed up a new batch of the tooling gel coat and we're just going
to apply this all the way over the surface of the inside of this mould just like we did
on the top mould.
Again we're going for that target 0.8 mm thickness which is a reasonably thick brush application.
now that the gel has cured we're just going to put down another coupling coat exactly
as we did before.
here again we're using the 225 gram glass but another excellent option for the coupling
coat is something even lighter like a couple of layers of an 80 gram.
So the coupling coat has no cured of and it's time for the main reinforcement again.
Just like before we'll be applying all of the reinforcement and the tooling resin in
one session.
We'll be using four layers of the 450 gram chopped strand mat.
So that's the underside of this mould finished so we'll allow this to cure fully overnight
and then tomorrow we'll be trimming these and separating them.
This mould has fully cured now so we've marked up a trim line all the way round the edge
equally spaced to where we know the bonnet comes to.
And so now we're going to trim them apart to separate them.
We're going to be using a jigsaw cutter to trim the two moulds and we're using a permagrit
blade which is a tungsten carbide blade in the jigsaw.
With the mould fully trimmed it's now time to some extent for the moment of truth and
what we're going to do is separate the upper and lowers moulds.
So to do it we're going to be using a chisel and trying to insert it between the two layers
of gel coat and then just tapping that in with a hammer, I think we can hear the moulds
releasing.
So we're just going to insert lollypop sticks now.
That's sounding good.
So that's our upper bonnet moulding done now and it's just time to remove the bonnet itself
from this lower tool.
We'll be looking at doing this underside moulding first because it's actually slightly more
complicated than the upper moulding.
So the first things that we'll do are pretty self explanatory we'll strip off any of the
filleting wax that's on the underside of the moulding.
We'll also be looking at taking off any of the release tape.
And finally if there's any blemishes such as this one here then we'll just be filling
some gel into those areas.
You'll fine that a chemical mould cleaner like this will quickly and easily strip off
the filleting wax and any other contamination from the mould surface.
So this area that you can see here, I think the paint actually wrinkled up on the underside
of the bonnet and it's left this blemish here so what we're going to do is chisel out all
of the paint and some of the gel coat so that we've got some fresh material and then we're
going to put some new tooling gel coat into this blemished area and sand it smooth.
So to make a repair like this what we do is we mix up just a small amount of the Uni-Mould
tooling gel coat a few drops of wax additive and the wax additive prevents the gel coat
from staying tacky on the surface where it comes into contact with air like a gel coat
would normally do.
Once the gel coat has hardened up and you can see that the wax additive that we included
has meant that there's no tackiness here then we can start wet sanding and flatting.
So we've flatted this out nicely now using the wet and dry paper, we're just finishing
it off with a 1200 grit before we go on and use polishing compound which we can either
apply by hand or as we're going to do using a polishing wheel.
Although both of these tools are now pretty much ready to use as they are to give this
a real professional finish what we're going to do on this top mould is give this a wet
flat all over with a 1200 grit and then we're going to polish it all over using an intermediate
polishing compound like this Mirka T10.
The reason for wanting to give it that flat on the surface is if you just catch the reflection
here of the light you can just see a very very slightly texture to the surface and that's
partly print through from the chopped strand mat underneath and other just surface imperfections
on the original bonnet.
We've now polished both of these moulds up to a high standard and so that actually concludes
the fist part in this video series.
In the next instalment we're going to be looking at using both of these moulds to produce the
parts themselves using the resin infusion process.
I really hope that you've enjoyed this video.
For more information or to purchase any of the products that we've used in this video
please visit our website easycomposites.co.uk.