fiberglass mold help

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#1

i need some advice on what to do about the mold i made…chuck it and start over or fix it.

it has a few air pockets…it looks way easier on the internet…then when you have epoxy all over your gloves an itch on your nose and the fiberglass is sticking to everything i thought to my self, hmmmm this isnt as easy as it looks. i did figure it out about 3/4 of the way thru. so the back side looks better than the front…:mad:

i think i should have started with a thinner fiberglass for the first layer. its the money layer. i think thinner would have conformed better.

anyways, i have a few air pockets. can they be fixed? if so…how???

im not sure what happened here…

im thinking, what if i filled a syringe with mixed epoxy and inject the blisters? then when they set up, sand them smooth. do i need to take a trip to the ghetto and buy a syringe off a heroin junkie (a new one of course)? my luck i would probly go to jail LOL.

#2

You could do that … Cvs walgreens will have syringes. But they make some with big needles. I would dig and fill the major surface bubbles and smooth it. Doesn’t look to bad just a little touching up to do.

#3

i can get the blisters with a syringe dallas. but what can i use on that gouge?

#4

Why aint you using gel coat ?

#5

About time you post this. :stuck_out_tongue: So that mold is just Epoxy and glass? You should look into a epoxy surface coat. This is epoxys version of gel coat basiclly. I think that could help your surface finish alot on the next mold. I would use this mold to practice filling in the small holes incase their is any problems with them on future molds. Try to get this mold to working condition but don’t be mad if it doesn’t work. Use it as practice so your next one goes that much easier and looks that much better. I’ve thrown plenty of molds away in my time. :mad2: I think it’s either two things that are causing those bubbles. Ethier it’s because you’r just learning mold making or that woven glass just doesn’t want to conform.

#6

Evercoat filler works good. Bond o works too but tends to shrink alot.

Next Time lay your fiberglass in smaller pieces. Its much easier and faster to build with 3-5" tape or at least cut strips as such.

Well if he would have used gel coat and tried to one shot it the gel coat would have hid alot of problems only to return later on. Looks good so far.

Any fast body filler is what I recommend. I’d also recommend getting the top planed out nicely as well.

#7

+1 I think that would REALLY help. Doug did you just use one large piece of fabric as your first layer?

#8

He could easily fill it and spray with a dura tec primer and polish it out. Or even spray with a gel coat. I’ve made much worse abortion status molds work and this hardly looks like an abortion…yet.:slight_smile: I think just like rotor… Push through this one an learn all you can.

#9

HOORAY!! the cavalry is here…:):slight_smile:

i just got back from home depot. i had to get a new pair of scissors. the last set…well…lets just say…they got epoxied…

ok let me answer a few of your guys questions. yes roto the mold is just epoxy and glass. and you are right about what went wrong… i am learning…and the fiberglass didnt want to conform. and yes…i tried to be bad ass and do the first layer in one piece. that was my first mistake. by the end, i was cutting the fabric and it layed down real good. that when i sacrificed my scissors to the composite gods…(i hope thats all they want) i do have three boys tho…hmmmmm.

i would really like to salvage the mold…the plug fell apart when i pulled the mold from it. its fixable but i would rather not.

i have tried every drug store in town for a syringe. no one will sell me one…ARGH!

so what are my options? cut the bubbles out wth a razor knife and fill them in with body filler? i have a body supply shop near by.

i would really like to make more than one part from this mold so if possible the fix should be more than temporary…

if you guys just give me a little direction im all over it…:smiley:

#10

im not sure what you mean by planeing the top out dallas. the whole top “flange” is smooth…it just looks jacked up…

#11

You have a dremel tool or better a pencil file. Using the smallest bur file you have dig in and rough those cavities up. Now take some brown grocery bag paper and roll into a tight cone. Tape it tight. Pour some body filler in a cup and slightly thin it out with poly ester resin. Orrrrr mix some epoxy resin with fine sawdust or something thats gonna thicken it all up. Sorta like adding flour to gravy. Maybe flour will work :slight_smile:

You could take some of the random strands and rub them in your hands so they get kinda cotton balled and jam it dry inti the cavities. Then squirt resin in.

The paper cones need to be super pointy at one end and then open in the other. White printer paper works ok. Use a whole sheet of printer paper if you try it.

You then cut a small hole at the end and then roll the cone down like toothpaste to get it to squirt out.

Man California is FING wierd where else do u get needles for diabetes or composites work than a drug store.

#12

dallas, are these the duratec steps you recommend i take? http://www.duratec1.com/Application_Guides/ag13.pdf

#13

Before you try an infusion please take pictures of the top and bottom of your mold. It’s good to have firm thick molds rather than thin frisbee molds that screw up time and money. Depending on how thick you layed up might wanna lay some csm on the back side and give some backing support might be a good idea to gusset the two bowls together with a piece of 1/2 ply wood and gusset the flanges. Just trying to jump ahead of you a bit.

Also a stronger mold will also reduce the tendency for those repairs from popping out.

#14

Are you laying you mould with woven?

#15

im totally with ya…the infusion must be pretty tough on molds. i have 4 layers on now but i can add more…and gussets too.

heres some pix. i tried to get some shots with the sun shining thru…just tell me how to proceed. im like a big sponge here…you guys are the journeymen and im the apprentice.



#16

Yeah deffinately but you realize you have polyester instructions and are building a epoxy mold. Right? Most people use the vinylester orange… Looks like you got the grey?

#17

woven??? i think so. like a fabric.

i just looked at the glossary…its a weave.

#18

i didnt realize that… yes epoxy. its more like a green tint. are the two not compatible?

#19

They are I for a second thought they only had the ve for composite epoxy surface products but it shows both pe and ve available. Screw 180 grit… I’d scuff 180 then knock it down with 320 before I ever think about spraying on it. 180 Is too coarse. Deffinately chemical wipe then water scrub with scotch brite… Let dry and covered and do it again in the morning before you shoot it. Amine and poly ester don’t like each other and they recommend in a different area of the website to make sure you pay attentiOn to the amine released from epoxy.

#20

Very very critical that you fill those scratches inside that mold. And don’t orange peel it. Sorta like a balancing act.

I’d reccomend taking a day to coat the mold… But we will get to that later.