Fiberglass & resin

[psycho72 1]

What are some good places to get this stuff? What am I looking for? Is there specific kinds? Are there cheaper ones and more expensive ones? How much is a good deal if I am searching on e-gay? How much will I need to make a 31x26x10.5 inch tub? How thick to I need to make it?

Thanks

Jerry

[Supa_c 1]

Its sold at just about every local hardware center and boating shops ( prob cheapest place)

As well as walmart

You are looking for normal resin, nothing with a gel coat

there are specfic kinds but thet are more expensive then the general stuff you need

Not shure on the price ATM but you could prob git r dune with 2-3 quarts

Thick, do around 3-5 layers

should be plenty strong

[psycho72 1]

Well are these good deals?

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewI...7523163094&rd=1

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewI...7524014905&rd=1

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewI...7163743123&rd=1

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...&category=26451

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewI...5982201425&rd=1

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...&category=26451

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...&category=26451

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...&category=26451

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...&category=26448

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...sspagename=WDVW

[Supa_c 1]

No idea, but most guys like the mat better than the woven stuff

[EFFENDI 0]

Sounds like you are going to be doing a spare tire well??? In that case, you are going to need all the strength you can get. I'd suggest woven cloth over mat. You will lost some flexibility, but cloth is (based on what I have read and heard) easier to work with for large areas, and is stronger. Use some lightweight cloth, lay down like 4-6 layers, with PLENTY of resin. I'd estimate that a gallon would be enough, but based on my experience, you can never really have too much. (I used a quart per doorpod if that tells you anything)

eBay is really a last resort for me. I'd rather go to Lowe's and buy the Bondo stuff rather than buy it in a huge quantity over the net. Select Products (selectproducts.com) also sells some great quality stuff, and they have a good selection, but they arent that cheap.

Marine/boat bulding shops often have great deals on cloth/mat and resin. Since you are in Los Angeles, this shouldn't be that hard to find. (Let your fingers do the walking in the Yellow Pages )

Good luck!

[Supa_c 1]

^ used a crap ton of resin

[EFFENDI 0]

^ used a crap ton of resin

<{POST_SNAPBACK}>

is that a metric or standard measurement?

[ngsm13 1]

Use a good amount of resin, hell I used 2 gallons on my door pods

I used the regular mat you find at Lowe's/Home Depot, I would NOT touch most of the ebay stuff you listed...except maybe the Biaxial stuff (last two links).

NG

[Nikuk 1]

To tell You the truth, mat < < < cloth. You can get decent weight cloth most anywhere (Hardware stores, auto stores, Marine shops).

I would suggest getting 'good' polyester resin & MEKP though... the cheap ass Bondo brand stuff @ Home Depot <<< Decent Polyester resin from a Marin store or online store.

Epoxy Resin > Polyester resin as well. Much better to work with and ends up just as hard.

USComposites.com has become my friend.

-Nick

[CBFryman 2]

all you really need for car audio is nothing more than the 6oz cloth you can get at home depot, the 6-8oz mat you can get at home depot and the Bondoresin you can get at home depot.

FYI Mat has greater strength in all directions but cloth has greater strength with the grain of the weav.

mat then cloth, also cloth is easier to work with. but when looking for strength with cloth lay at a 45 degree angle from the previous layre for maximum strength in all directions. mat also soaks up a lot mroe resin than cloth.

If you want to gel coat id reccomend getting some better stuff then the bodo you buy at home depot and of course the gel coat coloring. you can also get coloring for your resin. it can be picked up at any boat store but when i did do a gel coat i got it from fiberlay.com

[EFFENDI 0]

I found some interesting info:

Epoxy Resin vs. Vinylesters and Polyesters

Here is some technical data that you may find interesting regarding the differences between Epoxy Resin and Vinylester or Polyester Resins. In case you don't know it, Souris River Canoes are all made with a very high grade epoxy resin. Pretty much everybody else in the canoe world uses either vinylester resin or even weaker polyester resin. 

In the marine industry, liquid plastics, namely epoxies, polyesters, and vinylesters are used to saturate (wet out) the fibers of wood, glass, kevlar amarid, or carbon to form a fiber reinforced plastic (FRP).  To create a quality part, adhesion to the fibers is the most important factor.  Not all resins keep their grip on fibers equally.

Epoxy resin is known in the marine industry for its incredible toughness and bonding strength.  Quality epoxy resins stick to other materials with 2,000-p.s.i. vs. only 500-p.s.i. for vinylester resins and even less for polyesters.  In areas that must be able to flex and strain WITH the fibers  without micro-fracturing, epoxy resins offer much greater capability. Cured epoxy tends to be very resistant to moisture absorption.  Epoxy resin will bond dissimilar or already-cured materials which makes repair work that is  very reliable and strong.  Epoxy actually bonds to all sorts of fibers very well and also offers excellent results in repair-ability when it is used to bond two different materials together. Initally, epoxy resin is much more difficult to work with and requires additional skill by the technicians who handle it.

Vinylester resins are stronger than polyester resins and cheaper than epoxy resins. Vinylester resins utilize a polyester resin type of cross-linking molecules in the bonding process.  Vinylester is a hybrid form of polyester resin which has been toughened with epoxy molecules within the main moleculer structure.  Vinyester resins offer better resistance to moisture absorption than polyester resins but it's downside is in the use of liquid styrene to thin it out (not good to breath that stuff) and its sensitivity to atmospheric moisture and temperature.  Sometimes it won't cure if the atmospheric conditions are not right.  It also has difficulty in bonding dissimilar and already-cured materials.  It is not unusual for repair patches on vinylester resin canoes to delaminate or peel off.  As vinylester resin ages, it becomes a different resin (due to it's continual curing as it ages) so new vinylester resin sometimes resists bonding to your older canoe, or will bond and then later peel off at a bad time. It is also known that vinylester resins bond very well to fiberglass, but offer a poor bond to kevlar and carbon fibers due to the nature of those two more exotic fibers.  Due to the touchy nature of vinylester resin, careful surface preparation is necessary if reasonable adhesion is desired for any repair work.

Polyester resin is the cheapest resin available in the marine industry and offers the poorest adhesion, has the highest water absorption, highest shrinkage, and high VOC's.  Polyester resin is only compatible with fiberglass fibers and is best suited to building things that are not weight sensitive.  It is also not tough and fractures easily. Polyesters tend to end up with micro-cracks and are tough to re-bond and suffer from osmotic blistering when untreated by an epoxy resin barrier to water.  This is really cheap stuff.

Summary - Epoxy resin has far more to offer in its ability to flex, prevent delamination, and ease of use for repairwork. Using epoxy resin leads to better quality products. 

[psycho72 1]

Okay so now I am really lost.

I have 3oz, 6oz, 10oz, plain weave, satin weave, Dbl Plain weave, tape, 635 Thin, 150 Thick. What exactly do I need. I am not so cheap that I have to go for the cheapest. I want a good quality box that is not gonna flex all over the place but I also don't wanna throw money away for nothing.

[CBFryman 2]

Epoxy also cost a chit load more and polyester resin and fiberglass are fine for 99% of audio projects... you jsut have to make it thick enough.

[Supa_c 1]

where is REQ when you need him ?

[Nikuk 1]

make sure it;s thick enough? So use twice as much polyester and it's still cheaper?

O.k.

[CBFryman 2]

lets see, you can get a gallon of polyester for as cheap as $30...

do you have any idea what a gallon of epoxy cost around here? lets just say the chit that takes forever to harden completely cost about $40 a for 2 qts...and that is the cheap stuff...

[Nikuk 1]

http://www.uscomposites.com/epoxy.html

$48.50 for a gallon / quart of 4:1. Pot time of 10 minutes, set time 1-2 hours, Full cure in 3-4.

Shipping is ~$8 iirc (last time I bought a gal.). There is no hazardous charge or anything for two part.

BTW - they are in FL somehwere.

-Nick

[Nikuk 1]

lets see, you can get a gallon of polyester for as cheap as $30...

do you have any idea what a gallon of epoxy cost around here? lets just say the chit that takes forever to harden completely cost about $40 a for 2 qts...and that is the cheap stuff...

<{POST_SNAPBACK}>

+$6 for the MEKP, right?

[psycho72 1]

http://www.uscomposites.com/epoxy.html

$48.50 for a gallon / quart of 4:1. Pot time of 10 minutes, set time 1-2 hours, Full cure in 3-4.

Shipping is ~$8 iirc (last time I bought a gal.). There is no hazardous charge or anything for two part.

BTW - they are in FL somehwere.

-Nick

<{POST_SNAPBACK}>

Exactly what I was looking at but which one 650thin or 150thick? And what about the glass. You said that cloth was better than matt but what weave? What weight? How much do I need?

[Nikuk 1]

Definately the thin resin. Otherwise, wet out will be a pain in the ass, especially with 4:1.

For sub enclosures I use 3:1 epoxy with 6oz "S" glass. I do exactly as CBFry mentions: Lay one layer of cloth (resin it and let it tack awhile), then lay another layer of cloth at a 45* angle. Depending on the actual shape of the box I use 4-6 layers as a minimum.

If Your going to use 4:1 I'd suggest going up to 7.5oz to combat the brittleness (sp) of quick curing resin.

$0.02

-Nick

[psycho72 1]

Definately the thin resin. Otherwise, wet out will be a pain in the ass, especially with 4:1.

For sub enclosures I use 3:1 epoxy with 6oz "S" glass. I do exactly as CBFry mentions: Lay one layer of cloth (resin it and let it tack awhile), then lay another layer of cloth at a 45* angle. Depending on the actual shape of the box I use 4-6 layers as a minimum.

If Your going to use 4:1 I'd suggest going up to 7.5oz to combat the brittleness (sp) of quick curing resin.

$0.02

-Nick

<{POST_SNAPBACK}>

Since this is my virgin glass job, 3:1 would probably be better as it has a longer cure time.

And as far as the 45 degree would that be 45 on #2 then another 45 on #3 and another on #4 eventually making it full circle?

[CBFryman 2]

youd be surprised on how fast your first jobs go...sure it makes things safer but id rather mix up a small portion, glass it in, then have to mix up more and do another area and have both cure quickly then waite over night to get the chit to cure. my first glass project took 2 days to cure completely because i thought i would go the "safe" way and mix less hardener than reccomended...now when i glass, for the most part, i mix it very hot because i get done with what im doing in only a few minutes... gets tacky enough to do another layre in 10-15min and gets gelly in 5min...but im talking with polyester resin, with epoxy they give you an aprox cure time and you ALWAYS mix to their reccomendations...ive found that out the hard way...too much hardener and its brittle and curse WAY to fast, too much resin and it never gets past gelly type stuff with out days to cure or a heat gun. use of a heat gun can also make it brittle.

[EFFENDI 0]

Even though I posted that article excerpt, I think polyester resin will serve you best for your application. It seems that you are trying to keep costs down, and most of the shops I talked to in my area all use polyester resin.

[CBFryman 2]

Polyester is cheaper, strong enough for audio, and more easily obtainable, plus you can ONLY use polyester in most fiberglass mats because they have chimeicals in the glass strands that help POLYESTER resin adhear and soak in.

NjccBflo said 5-6layres with epoxy...

about the same (maybe an extra layre or two) will do in most cases with polyester. but it doesnt have to be as thick if you have a lor of curves because curves is where polyester (and any fiber composite) is strongest.

dont mean to call you out NjccBflo. Epoxy is great when building surfboards, extra light and even stronger for ding/dent prtection...but for car audio, polyester is fine.

[Nikuk 1]

oh I agree that it's fine... I just said that its easier to work with.

-Nick