Fiberglass Options

[bojangles_8686]

I think I'm going to try making something out of fiberglass. Ive wanted to for some time and finally I decided I want to make something small just to see how hard it really is lol. I know the process but I just dont know all of the materials I need. I already have an electric sander and some fiberglass body filler (i guess I can use that to make the whole thing look smooth, right?) What else do I need, and does anybody have a suggestion for a beginners fiberglass project?


Thanks,
Chucky

[Phat_99CeliGT]

time and patience is #1
if u don't have that, then don't bother.

Fiberglass mat, resin, sometimes felt.

[Coomer]

Yeah, fiberglass takes a long time to make something big out of it. And then it takes even longer to get your project to be smooth and ready for paint.

For materials, I suggest the following:

Latex gloves(I got a box of 100 for $10 or something)
Good Mask(At least a particle mask made for fiberglass...fiberglass fumes are not fun)
Cheap Paintbrushes(I got 2" wide ones for $.77 a piece or something at Home Depot)
Acetone(Optional, but you can let your paintbrush sit in acetone and then the resin won't cure and get hard, and you can use the brush again)
Fiberglass Mat/Cloth(I've never used cloth, but apparently it's better for sharp curves and corners and stuff...I just used mat for everything though)
Fiberglass Resin(I suggest buying by the gallon...it's cheaper, and you'll use a lot of resin)
Extra MEKP(I've found that the amount of MEKP, or hardener, they give you with the resin isn't enough, so I just always buy another tube)

Those are the basics...if you tell us exactly what you want to make, we can help you out more.

[bojangles_8686]

Thanks for the info guys... but im still not sure what to make. My friend said he would give me the diameter of his subs so I could make a sub enclosure. It would most likely be a simple design, not anything like soundsluts or bkholers but something small. I know I would need a template cut out for the subs, but how would I make the basic frame of the box?

[Coomer]

You can make it using MDF, or fiberglass. It all depends...where exactly is the sub box going to go? Do you have a picture of your friend's trunk of his car?

[celimanST]

A good place to get FG is a boat repair shop they will generally they sell the resin by the gallon and FG mat.

FG mat vs. FG cloth = mat is alot stronger and cost quite a bit more.

Don't comprimise on a mask get a good M3 mask the fumes and FG particles in the air dangerous!!!!

[toyotaspeed_90]

coomer... too bad you don't live here anymore.... there's actually a shop just for fiberglass stuff.....

i get my gallon of resin for $23.... the hardener is $7, which will generally last me through about 2 gallons or more (i've gone through about 5, and only used 1.5 bottles of hardener)..... the .75oz matting is only like $0.80 per linear foot (by 3 feet wide)... they have from .75 all the way up to some really thick stuff.... they also have all the different cloths as well, gloves, color for resins (wierd, i know), brushes, rollers, everything!

anyways..... the fumes aren't that bad as long as you're in a ventilated area... but you'll want a mask for when you sand/grind... i'm dumb and don't use one all the time

btw.... CLOTH is a lot stronger... it's woven.... matting generally is easier to build up though.... and matting is cheaper

[bojangles_8686]

[Coomer]

[Drocay]

[celimanST]

[toyotaspeed_90]

i'm sorry..... matting is NOT stronger than cloth.... generally cloth is thinner (when talking about the same price levels per linear foot) so it appears to be weaker......

if matting is so strong.... then why don't they use carbon fiber matting? makes no sense..... the strength is due to the cloth being woven

AND matting is CHEAPER

[celimanST]

i did alot of research before i started my FG projects and everyone until now has told me that matting is stronger. Now if the people who use FG for a living a wrong well I don't know what to think. I also priced matting before I started it was $15-20 more than cloth where ever I looked.

[NEVERSTOP]

One thing I would recomend... wear TWO pairs of gloves makes clean up a little easier and your less liky to got the resin onto your wraists... which is a pain.

Also you don't really need a paint brush, but some people perfer it. I personally just use my hands and work the resin into the glass before I apply it then I run my fingers down it to get off all the excess resin and loose fibers - that way when I lay it down there isn't too much small fibers everywhere which can happen sometimes with the dabbing of the paint brush. The most important thing that I have noticed is to makesure that you have your resin evenly over everything, a dry spot is a pain to deal with.

You might want to also look into an accelerator for you resin. I don't usally use it but it sometimes really helps, but can turn your glass purple

As for the matting/cloth issue:

sSo everyone knows what I am talking about
cloth - thicker strand woven sheet, smooth feeling



matting - actual fiber, coarse feeling



Matting is alot better than cloth - period.

And here is why

Matting is woven 100x more that ne cloth I have ever seen. This increases the strenght of it alot, It is also generally multi layer strands that intersect at either 45 degree angles or 90 degree angles within each piece which adds alot of interal strength to the piece. When you lay your glass down by hand and are doing mutilple layers you should be rotating the pieces whenever possible so that the weave in the matting is at 45 degree angle from the layer below it - this is simple geometry and most of you should be able to understand what I am talkin about and why this is important for strength, if you are building a piece with alot of flex needed lay the pieces all in the same direction. Also the strands inside the matting are generally shorter than in the cloth. This also adds strength, think of a 6 foot 2x4 - its gonna be alot eaiser to break in half than a 3 ft 2x4. It will also flex less the smaller it is.

If that dont convince you let me ask you this...

When was the last time you walked into a body/custom shop and saw them using cloth in a fiberglass chopper(spraygun)???

Now I'm not saying that cloth doesn't have it purposes.. but for the kind of stuff that most of us will use fiberglass for the cloth really isn't gonna cut it. It has been my experince that the cloth works best for light weight repairs with minumal amount of sanding, it is also good for areas where there will be alot of flex. But its is harder to work with than the matting for tight areas. Cloth is not something that should be ignored, like I said it does have it's purposes but for the level that most of us are going to be working on.. just use the matte it will be alot better for you.

Point is though.. use what you want and what you feel comfy with and lets not argue about it cuz its pointless

[pxcr440]

i read it all but i dont think anyone said that when makeing a sub box take your rings mount them how you want and strecth fleese across the hole thing then buuild from the insid eif possible that is what i do and i have found that it cuts sandign time down alot cause your surface is alot smooth , make sure you wash the fleese first other wise the resin wont soak through sometimes , fleese well work on any project ,and save time

anything thats saves time on fg = good

This post has been edited by pxcr440: Apr 17, 2004 - 12:30 PM

[Coomer]

[celimanST]

[toyotaspeed_90]

ok..... i think all of you aren't using the same fiberglass or something.... because what i say is from MY personal experience.... not what someone has told me.......

the "geometry" of the matting doesn't make a whole lot of sense...... think about it.... if you use your "45" and "90" degree angles theory, it applies to cloth as well since the strands are perpindicular to one another....

i have taken thinner cloth and thicker matting (that i have resined myself)... where i made a part and cut the excess off.... and the cloth was more flexible AND stronger.... it had a higher threshold before it broke... also, cloth is MUCH more flexible to work with (trust me.... making the complicated hood supports out of matting was a huge mistake... took way too long because it isn't flexible when working with it.... then making the same pattern the cloth was 100X easier to put into the same part)

also..... you're "a 6 foot 2x4 - its gonna be alot eaiser to break in half than a 3 ft 2x4" theory doesn't apply either..... with matting it's criss-crossed INDEPENDANT pieces of glass...... with a cloth, since it's woven, you wouldn't be applying the strength across the entire strand...... to put this into perspective in your theoretical ways... now imagine a 3 ft 2x4.... that would be easier to break than a 6 foot 2x4 with a bunch of other 6 foot 2x4's all put together into a big "woven" pattern... the pressure you apply on the end of the boards will be taken by the perpindicular pieces naild to that 2x4....

also... matting is easier to sand down than cloth..... again, this is from MY OWN personal experience in my garage.....

and seeing how i buy .75oz matting for $0.80 per foot and (i don't know the oz, i never paid attention on cloth) for about 1/2 as thin as that of cloth cost me ~$1.50 a foot..... hence cloth is more expensive

[toyotaspeed_90]

also.... again from my personal experience.... if you use your fingers to push in the resin.... it takes more resin to do so than with a brush (because the brush can hold a little bit of resin and has a flatter/broader surface to push it in than the point of your finger).... and makes for a stronger part.... when you use too much resin you are making the part much more brittle.....

[pxcr440]