help on making part

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#1

I am trying to make a splitter for the front bumper, I made a mold from the foam board since foam board has some thickness, but my question is how do I lay FG or carbon fiber in the mold and have the same uniform thickness with smooth flat on both side? picture below shows what I am trying to make, any other suggestion on how to make this part without using vaccum bag?:confused:

I spray my mold with spray can lacquer from auto zone does those auto paint good for surfacing the mold?:confused:

last question I did some research on the mold release, it suggest to wax the mold first AND then spray mold release agent, can I just do either wax or spray but not both? :confused:

Thank you for anyone who can help me with those questions.

#2

Rattlecan paint can surface a mold well enough, provided that you put sufficient time into sanding and buffing it, then waxing.

The idea behind waxing AND using a PVA-type release agent is double redundancyā€¦if one of the agents isnā€™t so perfect in a given spot, at least the other will be there for ya to help protect the mold and ensure a good release. Yes, you can get away with just waxing, but why take chances?

#3

Your post makes absolutely no senseā€¦

Slow down, ask clear and precise questions and some of us can help you. With what you just rattled off I cant even decipher what the hell you are talking about.

#4

sounds like you are still making the plug.
you need to stick the bits on your existing bumper,glass that etc THEN make a fibreglass mold of this new creation,remove the mold and then you can make a new part inside your new mold,release it and stick the new part onto your existing bumper,very basically lol.problem is your bumper will be destroyed in the first place if you cover it in fibreglass.
if you are just trying to make the carbon splitters on the bottom of the bumper in the pic then you need to make them out of foam,glass them and make a 2 piece mold of them,all off the car,checking what the plug looks like by just holding it up to the bumper.its an enourmous amount of work and expense for a one off job so if someone already makes them then just buy them.

im not sure that makes any more sense than his post lol :slight_smile:

#5

Iā€™ll take a stab at thisā€¦if your first question is about loading the prepped mold for a narrow part correctly or at all, then since your abit green to all of this, Iā€™d suggest loading the main walls first with two strips of CF and then the radius valley as a narrow stripā€¦of course backed up with glass or more CF.
As you get more experianceā€¦perhaps you can load the mold with a single larger piece. For a lower Splitter like thisā€¦the afore mentioned method will look decent under your clear Gelcoat/paint.
The rest of your questions are basic fundamentals you can SEARCH FUNCTION for.
Best of luckā€¦Vā€™

#6

Is this for a one off or a production run?

#7

Thank you for answer my questions but sorry for the confusion, I already made a mold as the picture shown, how do I lay carbon fiber AND/OR FG so I can have both side smooth and not only the side thatā€™s touching the mold? Some of you told me to use two piece mold but how does that work? Or am I going the wrong path about making this part?
I am trying to make couple of them for spare not just one.

#8

You make the molds so that they bolt together. Iā€™ll dig up a front air dam mold picture later after I ship some rush stuff outā€¦

You then will have to lay each mold half up and let it B stage, trim carefully and even with mold edge. Then bolt the molds together and pour your resin matrix into to bond the half edges together.?:confused:

#9

As I understand what youre talking about, you have a piece that isnt hollow but it needs to be smooth on both faces?

Thats a tough one in anyones hand.

What most would do is make the female mold and them make a mock part in glass (actually this is how Id do it) and then finish that back side while still in the mold and then build the male half of the mold.

Then you gelcoat both piecesā€¦wet out the part and bolt the two halves togetherā€¦kinda like GGROP saidā€¦

if its not hollow, you dont have much to worry about, the resin will bond the two layers together to make your new, very shiny and smooth part.

Bonding two halves of a hollow together is something I am still very leary about, especially if it entails me having the seam visible for a show sideā€¦

When I figure that out, Ill be a happy guy. Motorcycle gas tanks are my nemessis

#10

After posting my comment, I got rethinking (I know, that is dangerousā€¦:D) and since you are only looking at a couple of these, take 1/2" (?) PUR foam sheeting, shape it to your needs, CF overlay it and then clear coat them.

This way it is solid and with a simple wood veneer template laid on the PUR sheeting, it would be easy to remake them.

We are doing that to make skateboards in the classroom but with CF pre-pregs, oven curing under vacuum and man, those are really solid and stiff!:eek:

#11

Itā€™s alot harder than what that part looks to make, what if I just pour resin until flat surface on the other side?

#12

Resin by itā€™s self doesnā€™t have much strength has it is the combination of both the resin to ā€œglueā€ together the reinforcements (CF / FG etcā€¦).

I see you are in Anaheim and you could sign up for my free Composites and Plastics ROP class in Garden Grove, but do it soon as ab2448 has passed and within 1 to 2 years we have to have 90% high school students to 10% adults in all classesā€¦:mad: as we are now at 70% adults to high school students!

PS: Coastal Ent. donates a bunch of PUR sheets to us for the students to use!

#13

How do I find the class schedule and location? whatā€™s ab2448 ?

#14

(714)663-6497 or 663-6546 for information to sign up and that starts Aug.30th or soā€¦and tell them you read about it on here from the teacher, JM!

See the educators section here and AB2448 (Google it for more information on it)will mandate in less than 2 years that all ROPā€™s will be 90% high school students and only 10% adults! We are at 70% adults to 30% HS for CCROP (GG, Santa Ana and Orange).

Rancho HS 11351 Dale, Garden Grove near Katella and Beach Blvd. on Tuesday and Thursday (until enought students to have both classes seperate nightsā€¦) nights from 6 to 9:30 PM!

It looks like the class will be doing a plant tour (I might try and open the tour to others butā€¦?) of V-Systems in Oct. or soā€¦see jobs and careers section.

The ROP catalog discription for thenew 2x classes is wrong and I was going to write it up for them, but they never told when they wanted me to do the new classes discriptionsā€¦