Making copies of replica flares

[Graeme Stebbing]

Hi guys, perhaps you can help. as many of you will know I am building a Countach replica, I bought a body shell pre made, a good mate is building his the hard way from cad and making a foam plug, he has asked if he can copy my flares and front bumper , he is a panel beater and so works with bog all day, neither of us have any real experience with fibreglass moulding, originally he was going to take some paper patterns and draw it up in cad, I once used some bog to make a small mould about 6 inches long as a one off and it worked great, but this is a whole different matter.
I read somewhere probably on here about using a aluminium foil tape from 3m stick it on the body and mould off that has anyone done this, I could wax the body and then use pva release, but am reluctant to do this as it means trying to get the wax off again when it comes time to paint, would a couple of coates of pva over my gel coat, or the tape work, the mould he wants to take off only has to make 1 flair each, I suggested about 10mm of bog over the tape with a rebar or similar bent to the shape to give it some shape and to stop it turning into a floppy jelly. I am about 5 hrs from him so its a long way for him to come and find we can't copy the shapes.
any help much appreciated

 

[Frank Catt]

Graeme, you will get lots of technical replies and ideas on this one, but as a beginner like you I have done it simply by covering an area in thin shiny surface brown packing tape, wax that surface then normal gel coat and fibreglass lay up. The lay up needs to be at least 6 8 layers thick to be stable when removing it. Dont forget any mould lines that might prevent easy removal from the original, if you have any curve that would prevent release from the original shape just put two strips of ali bolted together, and lay up either side so that they seperate when you want to take the mould off, but go back together exactly when you want to make up the final pieces.

 

[Michel]

Hello
if you have a bare and new bodywork is not a big problme to mold copy some areas but ;
First of all is it smart to copy something you sourced from a manufacturer who invested in molds and toolings ? isn't anything writed about remolding in your bill of sale from this company ???
Secondly depending on how big is the area you want to duplicate sometimes mold material cost plus consuming time plus material for molding parts is much more important than just picking some parts from that manufacturer ( if they agree to sell separate moldings ( why not ? it's their job to do some spare and minimise their tooling cost expenses)
Otherwise if it's a complete front spoiler plus flares and if you decided to mold anyway ; that's a good opportunity for you to have molds in an eventual crash ( don't wisch to you this for sure!!
Issue with wax is not a problem because most of wax will come with the mold and you can easily wash your parts with acetone to clean properly those but this is only ok if you got real gelcoat on your parts and not primer !!
If you post some pics of parts to be molded ,it will be possible to show you how to do flanges and maybe separate molds to be sure to unmold correctly

Again before to go in such quite important work for first homebuild laminating try to evaluate if it's not better to source directly the needed parts !!!

Just to give you an idea, for a correct mold thickness and quality you have to multiply by 3 material expenses if you evaluate part surfaces in sourcing resin , strand matt, gelcoat , thinners , brusches
A part is more or less 1 x 100g strand surface plus 2x 450 and some rinforces on edges ; the mold is ( normaly) minimum 3 times that plus some foam fiberglassed rinforces not to twist

 

[Jac Mac]

Graeme, since your friend has/is building his own plug from scratch there is a good chance that 'his' car will not have exactly the same curvature/width etc as yours & therefore even if he copies your flares & front bumper they may not match the profiles on his own car requiring more work to 'make' them fit, my advice would be for him to take plenty of pics of your body in the areas concerned and then make his own foam plugs on his own car, that way everything should fit! & he will have molds for any future repairs he might require...after all they are the items most likely to suffer damage..

 

[Graeme Stebbing]

Hi Guys, Many thanks for the advice and tips they will help a lot, it looks like fibreglass is the way to go, as far as copying the parts rather than buying the originals, buying them is not possible as the company that made them has shut down at least 8 years ago, and as far as I can find out the moulds have been sold off or destroyed, and I never signed anything about not making copies. As suggested these moulds will be used to make one set, and then kept just in case of future damage. I have attached a few pictures below it would appear the rears are made in 3 pieces. Looks like as a beginner I could be in for a serious lesson on how to do fibreglass, luckily my friend has done a little in the panel shop so nothing ventured nothing gained. He has suggested after talking to a few people that to hold the shape you can use plastic tube ie garden hose to form a ridge on the back of the mould just to give it some rigidity.

Graeme

 

[Michel]

Hello
Ok if that's the case you can mold ;
Do you intend to mold only flare area or the whole wing ?
seems from your pics that the future mold can be if it's only flare in "one shot" ( no separate molds to unmold)
There is a groove on one side to be carefull to mold !! in this area you need to brusch carefully the initial gelcoat and then when cured properly ( means that the gelcoat is gelified but still sticking a little) you need to apply resin mixed with special cut fiber (long 3 mm) or roving "rope" to insert on the groove so this gelcoated area mold will be really in contact deeply with the groove .
concerning the rest of laminating is not an issue due to the simple form you have to copy ; eventually if you want to give more stiffness to the mold you can determine a flange where the mold starts ( bonding small wood blocks with double tape all along and then bonding on the perpandicular face of these square blocks cardbord flange covered by parcel tape or alu tape being cut carefull to copy acuratly the round form)
Yes you are right eventually you can use hose placed momentanly with spots of bondo and then covered by strand matt ( one ply) to rinforce torsion mold
This have to be done minimum 3 days after mold curing , not to impact gelcoat aspect thru plies thickeness

If you can source good stuff in a professional poly supplier it's advisable to buy gelcoat mold ( it's a green or blu color not much more expensive than part gelcoat but made specially for mold purpose)
Buy also "surface strand" 100gr thick (maxi 200gr); this first ply is used to prevent bulbs in contact to gelcoat area and laminated with good quantity of resin and rolled with special "anti bulbs" nylon of cooper groved small roll

Hope this helps:worried:

 

[Graeme Stebbing]

Thanks Mic, that's a great help, we only intend to copy the flares not the whole guards, the most economical way to buy the resin seems to be in a 11 ltr bucket, I guess it will properly take about 1 ltr per flair, so we will have just a little left over, my friend is going to do a test mould on a old car guard over the weekend using packing tape/with wax over then pva, then glad wrap pva , and then just wax to see which will be the easiest to do, can you please explain this part (nylon of cooper groved small roll) I have been told locally to use a fine cloth almost like a tissue first, over the gel coat.
I will let you know how it all goes.

 

[Michel]

Hello
some advises ;
Do not stick packing tape if you intend to wax plus pva ; sometimes packing tape melt with gel coat on places and result is awfull on areas where tape reacted ( and not every time... one day it's ok another it's dramatical
Usibg wax and pva is far suficient
Do not use clothes named roving or whatever similar stuff ( even thin) directly on gelcoat or in amold ; use only "strand matt"
To take off bulb when laminating use rollers like these ;
watch next post !
To calculate resin quantity ; evaluate surface then choice strand matt thikness
( 100gr, 200gr, 450gr,600grammes) and multipy by 2 to have total resin use
Sample ; 1.5 meter square mold of 450 gr strand by two plies gives ;
1,5x ( 450x2) x2 =2700 grammes of resin more or less 2,5 litres

Hope this heps

 

[Michel]

Some sample of rollers to take off bulbs when laminating strand matt ;