How to make a fibreglass mould UPDATED

[ozkat]

Part 1

Ill try to explain here in as much detail as i can with pictures how to take a mould from something.Im using a fibreglass dragbike seat unit for this purpose (its for a member here)

Things you will need....
Chopped strand fibreglass mat 600GSM weight
Resin, poly resin will be fine
Catalyst, to suit the poly resin (i use 725H)
Tooling Gel or normal Gelcoat
Mould release (i use TR on small stuff)
Icecream containers
Stirring sticks
Lots of rags
Eye protection ...PLEASE USE SAFETY GLASSES!!
Acetone
Disposable paint brushes
Small check roller
Rubber gloves
There is proberly something ive forgotten ill add it as i remember.
All this stuff is available from any fibreglass supplier.

This is the mould release i use
http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0313howtolaminate10001.jpg

Ok here is the tail im going to take the mould from. Im using this as ive gotta take a mould from it anyway and its relatively easy to do. First of all it mus be clean.... very clean. Wash it in warm soapy water to clean it and make sure its 100% dry. Anything your taking a mould off must not be porous if it is seal it with paint. Any marks, scuffs or scratches will show up in the mould and in the finished article.

http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0313howtolaminate10002.jpg

You will need to wax the article you intend to take the mould off at least 5 times, leaving it 15 mins between coats, using the foam applicator and buffing it off with a clean rag. Try not to touch whatever your waxing with your bare hands after you start waxing as the oils in your skin can cause the mould to stick, i recommend wearing rubber gloves.

http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0313howtolaminate10004.jpg
http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0313howtolaminate10005.jpg
http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0313howtolaminate10003.jpg

Once you have waxed the article you then move to applying the tooling gel or gelcoat. I use tooling gel as its made for moulds its harder than normal gelcoat. But if your doing a one off piece for yourself normal gelcoat will do, you will proberly be able to get 10+ pieces out of normal gelcoated mould anyway, compared to 200+ using tooling gel. Pour your gelcoat into a container (i used a washed out milk container for this) pour out the amount you think you will need then double it (you will be suprised how much you use, but dont worry its not expensive) Then you add your catalyst. Never use more than 2.5% catalyst unless you want to burn your shed down!
WEAR YOU SAFETY GLASSES AND RUBBER GLOVES!! This is bad shit! Get it on your skin and it will burn like acid. Get it in your eyes and you will be blind, no maybes YOU WILL FUCK YOUR EYES IN LESS THAN 10 SECONDS. Try not to breathe the fumes too much too.
I mixed my catalyst at a 2% ratio (i used 400grams of gel and 8 mils of catalyst)
Just brush it on nice and thick dont worry too much about runs they dont matter, just get a good thick coverage. Or you can spray it on just use a gun with a min 1.7 tip.

http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0313howtolaminate10007.jpg
http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0313howtolaminate10008.jpg
http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0313howtolaminate10009.jpg

Like i said dont worry about runs but make sure you get a good coverage. Try not to work the brush too much as you will just put more brush marks in it, you will see what i mean if you do it. When i used a 2% catalyst ratio i had about 30mins working time before the gel started to harden. The hotter the weather the quicker it goes off, try not to do it under 15deg or in direct sunlight.
And DONT BLOODY SMOKE WHILE YOUR DOING IT UNLESS YOU WANT TO BLOW YOURSELF UP!!
http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0313howtolaminate10010.jpg

You will proberly end up with some gel left in the container, dont just throw it in the bin pour water on it and leave it till tomorrow till you bin it, it can catch on fire.
Let the gelcoated article sit for 24hrs before you start the next stage. Use the acetone to wash up.
Ill be doing this in a few stages because im sure there will be a few questions and i dont want to answer too many at once.

Part 2

Now you should have a hard coating that still feels a little tacky on the article you want to reproduce. Dont touch it too much as the oils in your skin will cause problems. Next you need to cut your chopped strand mat to suit, allowing for around 30mm overhang. This will be trimmed off later but you need it there now.
http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0314howtolaminate10001.jpg

You can trim it into smaller pieces or put cuts in it to make it easier to go around certain shapes. You need to do this 3 times as you need to make 3 layers.
http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0314howtolaminate10002.jpg

Remove the fibreglass, making sure you know which bit goes where. You now need a wetting out surface an old table to or work bench will be ok but make sure its clean with no oil residue on it.
http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0314howtolaminate10003.jpg

Now mix your resin with cayalyst in the same ratios at you did the gelcoat (no more than 2.5%)
AND WEAR YOUR BLOODY SAFETY GEAR!
Once mixed you are ready to wet out the glass
Using a brush wet the glass in a dabbing motion using enough resin to totally wet the glass right through, but not too much that it runs off when you pick it up.
http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0314howtolaminate10005.jpg

Lay this wet glass onto the article piece by piece till its covered leaving about 30mm overlap. Then brush more resin on in a dabbing motion till the glass is fully wet. Using the check roller roll the wet glass in a random motion till you think all the trapped air is out, its hard to explain but im sure you will work out what i mean. If you see a bubble or a white dry looking area roll it maybe even add a little more resin.
http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0314howtolaminate10007.jpg
http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0314howtolaminate10006.jpg Wet all the glass right to the edge not just the edge of the thing you are taking the mould from.

You need to do this process 3 times. Smaller articles can be done in one hit larger items may have to be done in 3 stages. It depends if you can get it done before the resin starts to set.
http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0314howtolaminate10011.jpg

After you have done this 3 times leave it 24hrs for the resin to fully harden. (dont take too much notice of the blue lines in mine i used a different woven mat for my last layer you wont need to do this)

After 24 hrs it should look like this
http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0314howtolaminate10010.jpg
It should be hard but maybe still a little tacky to touch.

Next get a angle grinder and grind off the excess overhang, being careful not to damage the original item. (i forgot to take a pic of this)

Next is demoulding DO NOT USE SCREWDRIVERS OR METAL OBJECTS to help you demould.
Its hard to explain but you need to push, pull, flex, twist without damaging either the mould or the item your moulding from. You can use small pine wedges to help you demould but dont bash them with a hammer. If you have waxed properly and take your time you will end up with something like this.
http://i156.photobucket.com/albums/t31/GSXR1370TURBO/2008_0314howtolaminate10012.jpg

[sharky]

quote:WEAR YOU SAFETY GLASSES AND RUBBER GLOVES
Yes....always mate......tut tut [B)]

But bloody good 'how to'.....keep it comin.

[Bear]

Mate, top stuff! *applause* :)

[ozkat]

quote:Originally posted by sharky


quote:WEAR YOU SAFETY GLASSES AND RUBBER GLOVES
Yes....always mate......tut tut [B)]

But bloody good 'how to'.....keep it comin.
Do as i say not as i do, i did have safety glasses on tho. I cant stress enough how bad catalyst is if you get it in your eyes!

If i get home from work early enough tomorrow night ill show how to lay the fibreglass up.

ah yes...now i see the problem,i've been using Mould release instead of Mold release,and i was misusing the resin to

[JackTar]

quote:Originally posted by sharky


quote:WEAR YOU SAFETY GLASSES AND RUBBER GLOVES
Yes....always mate......tut tut [B)]

But bloody good 'how to'.....keep it comin.


Let's not talk about workshop safety practices given your recent track record Russ but yes keep the posts coming OZ, you are making it look easy mate.

[JackTar]

quote:Originally posted by davo

whats fibroglass?


Glass house walls. Fuck davo do you know anything?

[sharky]

Fair comment mate, but rubber gloves and glasses wouldn't have helped much.. :(

[JackTar]

quote:Originally posted by sharky

Fair comment mate, but rubber gloves and glasses wouldn't have helped much.. :(


Yeah sorry mate low blow but ya did ask for it ;)

[-Dex-]

I love shit like this. thanks for posting Ozkat.

[motogp_nut]

Thanks Oz that's awesome!!

[sharky]

So it was a Blowy Low Blow [:p]

[Jockney Rebel]

ta ozzie mate ive been waitin for something like this

[Fight_fan]

Thats unreal Oz! Thanx!

[DCRacing]

Good work on the post, i am needing some new glass for the race bike and was thinking how do i do a mold etc. Perfect timing, Although, can you give us a few tips on more complicated molds at the end of this initial one, and where would you get a suitable spray gun for this sort of work? or will a normal spray paint gun work? with the right tip.
Top stuff tho. Keep it coming.

[Fatgit]

Good one Oz, just what this dodgy builder wanted.

[Billy Bob]

Wow thanks man ive been doing research on how to make a tank cover, but cant find that much help so im watching in antisipation. "ledgend"

[fimpBIKES]

thanks ozkat!!!
thats awesome work

just as a bit of a query....
if i was to be doing a foam plug that was sacrificial would i use body filler then paint to seal it (before i got to step one of your fantastic how-to)?

[ozkat]

Yes fimp it would be best to paint it as the finish of the final product will be an excat replica of the original item + it prevents sticking up

[xb9r]

Ahh the mysteries of fiberglass finally being unlocked unreal Oz keep em coming

[Docktor]

Soo. The gelcoat came off the original item and stuck to the back of the fibreglass ?. right ?, And that r what gives you the smooth inside for the next one ?. So when ya buy something "gelcoated ready for paint" they have made it and then gelcoated it again on the outside ?

[sharky]

Nah mate, after waxing the mould you put in the gel coat and then lay the f/glass and resin...so when you remove the item from the mould the gel coat is there ready to paint......I think...

[Docktor]

Lets wait in anticipation for the next thrilling chapter ?.............

[xb9r]

Once we all get deadly at fiberglass can you show us how to do carbonfibre like you were talking about the other weekend ?

[Seifer]

If you want to see it in video form, this guy has a pretty good youtube series on how to fibreglass including two-part moulds etc.
http://www.youtube.com/watch?v=DEa5_WHQZo0

[Fish]

Hey you blokes with the sticks!!! Can we make this a sticky?

[Gix11]

Yea, I'm waiting for the next installment as well so we can do a "How To" page. ....I'll make it sticky until it's done.

quote:Originally posted by Gix11

....I'll make it sticky

just like the centrefolds in your Boyzone porno mag collection.[:0]

[Lucas]

Hey OZ.

Tell me to getthefuckouttathisthread if you want but can I add for those who may need it..[:p]

Cutting glass with a grinder, get a diamond cutting blade

Wait til the glass has gone off, ie cured completly. Cutting wet/tacky/ glass if really messy and you'll stuff your work.

Trim back as much overhanging glass as you can with a stanley knife as it curing, the less cutting/grinding later the better (wait til its stiff but still tacky, too wet and you'll fuck it, too dry and you won't be able to cut it).

Glass is itchy as hell, especially when its still green. Be prepared to scratch like a crazed ice addict.:D

[ozkat]

Ill get the 2nd part up as soon as i can, im kind of busy with wotk and pulling the Busa motor down and got the flu at the moment.
Good points Lucas but most of the blokes here are doing one off work so ive tried to keep thigs as simple as possible.
Most people have a grinder and its alot easier to shape things than use a cutoff wheel.
Wait till the glass goes off, i think most would leave it till it is anyway
I didnt mention green trimming because its to hard to explain when the glass is ready to green trim, and if you do it to early the glass will delaminate.
Wear correct safety gear and you wont itch, dont do it in your undies.

[Large]

Some great info here Shayneee

What about if you need to do a split mold?

[auskat]

Oz,
Great job with this mate - i am making a one off tail for my Suzuki and am nearly at the stage of making a mould. This will help me out no end. I've done plenty of 'glassing but never done a mould.
I'll cross my fingers, hope I don't go blind & see how it goes.
:D

[Seifer]

Take photos bloke, lots of them and then share with the world please.

[zx12argh]

Top work Oz - thanks mate.
And here i was thinking that thongs and shorts was sufficient safety gear...

[Eukanuba]

how does it go, if you've made a mold out of polystyrene ? wont the resin just melt it out ?

I'm looking at a custom tail, laser cut from foam..

[Seifer]

Cover it in tape first Eukanuba.

[336LJ]

Hi great article,
I too would like to add a few things (if I post hijack just delete the post I'll understand!)

If what your making a mould of has sharp creases/ruts. chopped strand matting is quite a prick to use so I usually chuck in a few layers of tissue glass before using the matting. it doesnt go far, and is time consuming but you can fill the holes/lines etc up flush, or put rounded corners on sharp creases so you can get the heavier matting to roll on better. same goes with making the item from the mould.

on trickier moulds we had an air hole drilled into them and plugged with plastecine or a sticky dot with wax, over the hole on the gelcoat side. u should use the wedges to release the mould, if it sticks leave them tapped into the mould, and blow a bit of compressed air into the hole, SLOWLY or you will blow the guts out it, or it will crack. I found moulds release better after being left to cure in the sun for ages.

and from memory, to get a mirror finish on the gelcoat on the final product sand the tooling gel on the mould as if your polishing it. should help release better too and imperfections on the original plug wont show up on the replica

I actually had fun at my old job makin moulds n stuff but hardly got to do it. I took my rear fairing in from the toofitty and tried the liquid waxes they use and managed to get some moulds done without the gelcoat sticking to the plastic but got the shits cause they wouldnt let me take them home when I quit so I binned them (after running them over with the forklift a few times)

[336LJ]

quote:Originally posted by Eukanuba

how does it go, if you've made a mold out of polystyrene ? wont the resin just melt it out ?

I'm looking at a custom tail, laser cut from foam..


see if they can cut it from a foam that is resin restistant, it will be quite a hard foam, almost like balsa. I forget wat its called... or how expensive it is.. there is a softer variety we used in pools, i THINK its called formchlor.

[Cruisecontrol]

quote:Originally posted by Eukanuba

how does it go, if you've made a mold out of polystyrene ? wont the resin just melt it out ?

I'm looking at a custom tail, laser cut from foam..


http://www.streetfighters.com.au/forum/upload/97782878412768.jpg


Tape it before you glass it.

[Gix11]

Any updates for this one Shayne??

[pt]

any updates?

[zx12argh]

Bump Shayno

[uncle pervy]

shit hot thread. I'm making a new tail for me speed triple out of carbon fiber(cause you just cant buy what i want) and used that sikaflex space filler shit to shape a foam unit. once i get the shape i want then it's going to bogged, painted, polished to be used to make the mold from. Now i know how to make the mold, sorta.
Thanks

[DCRacing]

Hey Oz, Now i know why people pay heaps for this sort of thing, i am taking a mold of a fuel tank to make a cover for the fuel cell, and i think i used to light a matting, 450g, it was all i could get and it kept falling apart on me from the table to the tank, then because i think i got a few large concentrated lumps on the tank i think it got a bit hot, i gather when you get a large growing black spot it is a touch too hot?
Anyway i will see what has come of it when i try to pry it of the tank. Heres hoping it is all ok.

[CBRRRT]

Brilliant matey!

[cannibalanimal]

Quick Q.. how do you prevent the gelcoat from doing the crinkling thing under the fibreglass?? Or have I just added way too much catalyst??

[opindown]

DCracing, if you want i can give you a hand glassing. done a bit of glassing in the past. and the black spot that is to hot to touch means you prob put shitloads to much catalyst in the mix

[cannibalanimal]

does not melt the piece I am taking the mold off as they are abs plastic I think. just the gelcoat crinkles up like tin foil under the chop strand and gp resin.

[ozkat]

quote:Originally posted by cannibalanimal

Quick Q.. how do you prevent the gelcoat from doing the crinkling thing under the fibreglass?? Or have I just added way too much catalyst??
The crinkling you refer to is called tripe. 2 Reasons cause it, if your gelcoat is too thin it will tripe. Gelcoat should be applied at about 25 microns thick, you can buy the little plastic gauge from FGI or ACME for a couple of dollars. You can regelcoat any spots you think are thin when the geloat is touch dry. The 2nd way tripe is caused is by applying the glass and resin before the gelcoat has gone off. To be safe you can leave the gelcoat to harden overnight then apply the glass and resin the next day, i wouldnt leave it anymore than about 12hrs tho.

[ozkat]

quote:Originally posted by DCRacing

Hey Oz, Now i know why people pay heaps for this sort of thing, i am taking a mold of a fuel tank to make a cover for the fuel cell, and i think i used to light a matting, 450g, it was all i could get and it kept falling apart on me from the table to the tank, then because i think i got a few large concentrated lumps on the tank i think it got a bit hot, i gather when you get a large growing black spot it is a touch too hot?
Anyway i will see what has come of it when i try to pry it of the tank. Heres hoping it is all ok.
James, taking a mold off a tank can be quiet difficult simply due to the size and shape. If the glass is falling apart you are possibly working it too much, if your using a brush and not a roller that may be the cause. Try using smaller peices like a patchwork quilt over lapping it by about 1 inch. To make a tank mold if your using 450g you will need about 6 layers. Dont try to do it all at once it will get too hot and the resin will go off while your trying to do it. Just do 1 layer at a time, let it go off and apply the next layer. Just make sure it has gone hard before you apply the next layer. If time isnt a problem do a layer each day but scuff it up with say 80grit paper between layers. You can do it every couple of hours if you like. Just make sure the surface is hard, if there is any heat in it at all the resin has not gone off. Yes the black spots are too much heat, most likely its not too much catalyst just the resin pooling and causing the chemical reaction. Its much better to do a few thin layers than one or 2 thick ones.

[ozkat]

quote:Originally posted by opindown

DCracing, if you want i can give you a hand glassing. done a bit of glassing in the past. and the black spot that is to hot to touch means you prob put shitloads to much catalyst in the mix
Proberly best not give advice if you dont know what your doing. The advice your giving is not right. The black spots are caused by the resin being too thick in certain areas, not shitloads too much catalyst. If you had way too much catalyst the whole job would go off too quick or not go off at all.

[MONO]

quote:Originally posted by ozkat

Ill get the 2nd part up as soon as i can, im kind of busy with wotk and pulling the Busa motor down



What the