View Full Version : Question for those experienced in fiberglass

07-06-2003, 01:57 PM
Ok...so I'm beginning my first fiberglass project, a basic set of kick panels, and I've got a few questions for those who have experience.

1) Mats...I've seen stitched, chopped, and woven mats. What are the pros and cons of each of these? Also, what's the difference between fiberglass cloth and mat?
2) Fabric....I've seen some people say use cotton, others say polyester, others say polyester/cotton blend, others say fleece, etc. etc. Is there any significant difference between these? I've got some old sweatshirts that are 83% cotton/17% polyester that I was planning to use, just wanted to make sure they were okay before I start.
3) Resin/Hardener....I've already got a gallon of each, so I'm ok there, but I've seen some stuff called Duraglass. What's this do?

Thanks in advance

07-06-2003, 07:16 PM
1. woven is stronger but cost more then chopped. chopped is mat to me it looks like particle board and pressed together while woven is stitched like fabric and that is cloth .
2 i would use 50 cotton and 50 poly. cotton can shrink and cause problems........ like cracking.
3 you need more resin the harderner. duraglass i believe is coating for real good protection it is resistance against many chemcial and other abrasive products. dont think you need that

07-08-2003, 12:25 PM
1. The different kinds of mat's have different weights, and build purposes. The Stitched and woven are stronger than just plain old chopped mat. Chopped mat is what you find at walmart and auto parts stores most of the time. It's easy to use, comes in small pieces that are easy to use. It's very flexible, and will contour to curves very well. Great for kick panels or small items such as trim panels, or amp racks. Stitched mat most of the time comes with cloth stitched to one side. This is great for quick buildup, and has a great strength to weight ratio. I use a form of this called kyntex biaxial mat for building sub enclosures. Woven is the same thing as chopped mat but the glass strands are woven together instead of being chopped up and held together with chemical binders. However woven mat is some strong stuff. Much stronger than chopped mat. The intertwined glass fibers give woven mat great strength. But it tends to be a little harder to conform to complex contours. Cloth is a woven material that is used in conjunction with mat sometimes to increase strength.
2. I use fleece. It holds plenty of resin. It stretches and conforms exceptionally. Plus if you get cold while your working. You can wrap up in it . :D Yeah you can use your old sweatshirts. I have used them before, they work quite well. Just remember to cut the cuffs and collars off. ( Don't laugh the first time I forgot )

3. Duraglass is a name brand. It's the same thing as bondo hair/kitty hair. It's chopped mat mixed with body filler and resin. It's pretty usefull stuff. Because of the chopped mat it's alot stronger than body filler. But you can always make your own. Simply chop up some mat in tiny pieces. And mix it together with a little resin and body filler. Viola duraglass :)

07-08-2003, 01:01 PM
Good stuff, thanks ramos!

07-08-2003, 01:29 PM
Yeah man. Anything else just ask. Most of the glassing information is stored in the side of my brain that's not absorbing the fumes. :D :)

07-08-2003, 04:07 PM
much to learn i see........... ramos where do you buy ur fiberglass at???

07-08-2003, 04:24 PM
Fiberglast.com if I need something special. But most of the time I just go down to my local marina/ boat repair store. Lucky for me there is a rather large one 15 minutes from my house. :)

07-08-2003, 10:10 PM
ive kinda asked this question before but i was wondering how much mat you think it would take to cover about 4 to 5sqaure feet enclosure(thats the internal volume)?

07-09-2003, 06:58 AM
Wew.... that's going to be alot of mat. :D IT really depends on what kind of mat your using. If it were me and I was going to build an enclosure that large. I would try to make a panel or two out of mdf. Then use a biaxial mat for the rest. It would probably be in the neighborhood of 5-10 yds. :)

07-09-2003, 05:15 PM
I was planing on trying to make the back wall and bottom out of mdf will it still be around 5 to 10 yrds? how much do you pay a yrd for biaxial? think i can get it around $5, ive found it on the net for around 6.40.

DBM 1708 Knytex Biaxial
+/- 45degree
Contains double bias(17oz) stitched at 45degrees
along with one layer of 3/4oz mat.

07-23-2003, 09:05 AM
Locally I pay $5.50 a yard if I buy 10 yards or more. Which I usually do. :)