Fiberglass

I am sure there are many other threads about glassin but I found some stuff in Hope Depot and all the other threads talk about getting the stuff at boat stores

So I was looking around and found some glass cloth I dont know what weave it was or if there are certian strengths...it was pretty cheap. I didnt know what kind of resin to use so I was thinking maybe just the syringe stuff from the hardware store. After looking around the Depot though I found 1 gallon of resin for $25. I didnt know where the hardner was and found out it was a little tube in the top of the contianer. It was Bondo Brand and I dont know if this is a good strong epoxy to use. It says that it is used for fiberglassing only. I know you guys say West Systems but I dont really have acsess to any

So

Is the Fiberglass from Home Depot of a small enough weave and strong enough

and is the Bondo Epoxy strong enough to at least use for glassing but maybe to do other things. The only weird thing about it is the hardner is a tiny tube and there is a gallon of resin.

I plan on maybe using the glass to reinforce the joints on the Big Nuke

Thanks
Ryan

Ryan buy the sounds of it the epoxy you have it more like polyester resin which is about 1/2 as strong as epoxy, also which you fiberglass is it woven or a mat of lots of little fibers?

matt

Check the label!!!

If it's polyester resin...TAKE IT BACK!!!

Polyester resin sticks to wood. wood must be encased in it in order to stay put, even then the strength is marginal.

As an example of a boat hull is made of wood and covered with fiberglass cloth and polyester resin. If the hull gets struck with a hard blow, there will be white showing where the blow was. This the polyester/fiberglass pulling away from the wood.

Now if a wood boat hull covered with epoxy/fiberglass gets struck hard enough, there will be a dent. The fiberglass/epoxy cover will NOT pull away.

Reason:

Polyester "sticks to wood...

Epoxy "bonds" to wood!

The fiberglass cloth might be a little heavy. Hobby shops carry SIG fiberglass cloth in a very tight weave (easier to fill) in various weights/yard. From 1/2oz to 12 oz. cloth

Don't use the matt cloth, that's for auto repair.

Hope that answers some questions

sandman

You also want to use Zpoxy Finishing Resin... Great stuff! Be careful to avoid drips though.

They had mats of lots of little fibers just thrown together but I later found some cloth. The weave is pretty tight and even though I looked I could find nothing about the weight.

This stuff was definantly called epoxy but it didnt seem like it because of the small amound of hardner. It said it would bond anything. It listed wood, fiberglass, ceramic, and painter surfaces

I will make sure to double check the label to be sure it is epoxy

If this is epoxy will it work?....even though it has such a small amount of hardner

thanks

Ryan

Ryan:

Some of the folks around here have been using US Composites epoxy instead of the West System stuff.

It seems to work very well and is less than 1/2 the cost of the West System stuff.

Web site is:

US Composites
5101 Georgia Ave
WPB , FL 33405
www.uscomposites.com
561-588-1001


Some stuff to check out on the site:

EPOX-635312 Epoxy kit with 1 qt 635 resin and medium speed hardener

EPOX-635313 Epoxy kit with ½ gal 635 resin and medium speed hardener

EPX-P31 3 to 1 ratio pumps for epoxy kits

FL-AER010 Aerosil filler 1 qt

FL-AER025 Aerosil filler 2.5 qt

FG-C0430 4oz E Glass fabric 30” width
FG-C0450 4oz E Glass fabric 50” width
FG-C0427S 4oz S Glass fabric 27” width
FG-C0638 6oz E Glass fabric 38” width
FG-C0660 6oz E Glass fabric 60” width
FG-C0630S 6oz S Glass fabric 30” width


Hope this helps.

Al

Welcome to the forum Al. Thanks for the information. I am sure some of us will find it useful. I may take a closer look at that when I get more into fiberglassing.

Welcom Al and thank you for your reply

I went to Home Depot agian and found out you were all right and it was Polyester Resin. After looking at the page Al gave I saw that polyester resin is also called Fiberglass Resin and contians Styrene. This stuff had both these qualities and on the side said "for tough long lasting jobs use Bondo Brand Epoxy resin" Well of course. They didnt have any. I will have to look around.

I bought some cloth. It was $4 for 9 square feet and is probably 12oz. The weave looks pretty tight so shoilnd tbe to hard to fill.

for the epoxy can I use regular 2 ton. That is sold at another hardware store I know of in large quantities.

The prices at that place are very good! The carbon fiber cloth is about half what it is at Fiberglast. I may have to get some of that for the fins on my L3.

glassing was easier then I thought, I used the woven stuff, now the tube is really strong, I don't think it would hold up if I didn't glass it. Now i just gotta launch it

Ryan and N3TJM:

Finally signed up. Have been reading the forum for about a year.

Glad to have been of some help. A couple of other epoxy things I have learned the hard way.

The thin consistancy of the West/US Comp helps the wetting of the fiberglass cloth. The typical 1:1 hobby epoxy/Walmart/Home Depo does not do this very well.

The filler I mentioned in my original post ( and West Systems 406 filler ) can be added to epoxy to thicken the material and increase its strenght. The West guide indicates a 3X increase in strenght is possible. Yes it also improves the strenght of hobby epoxy as well. I do all my fillets for fins and bulkheads using the filler. Have not had a failure yet.

Al

Originally posted by als57
The thin consistancy of the West/US Comp helps the wetting of the fiberglass cloth. The typical 1:1 hobby epoxy/Walmart/Home Depo does not do this very well.
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Click to expand...

Well I was trying to get around haveing to buy this epoxy offline but it looks like I have no choice. Unless I can find the bondo stuff.

Thats good that you can get the reinforcer...Now I can use it for more than just glassing

I have used the stuff from US composites for many projects. I am getting some West System to replace the 9 oz. hobby epoxy I would get at the hobby joint. I like to use West Systems 105 resin with some 206 hardener for fillets. I always add some chopped carbon (graphite) fiber. Sometimes, if you use a lot of the chopped carbon, put a light coat of regualr epoxy over the tube and fin where the fillet will be to soak into the material. Then put down the good stuff.
Go to US Composites. Get 3 or 4 yards of 4 oz. E glass and 6 oz. E glass along with some 1.4oz. cloth to use as a veil. The 1.4 oz. cloth is not on thier website, so call them for the product number.

Ryan,

You can use the 12 oz. glass, but it's pretty heavy and I really don't think you'll be happy with the results as the weave is awful thick. I'd go with boatsandrockets's suggestion. I use US Composites epoxy for laminating and, while I've never used West Systems, the US Composites stuff exhibits all the qualities that make the West people so happy.

hmm for some reason I cant see the replies to this post

Never mind. Just needded to post and it came up. Thanks for the suggestion Kermie. I am only gonna use this for internal glassing of the fins to the MMT

Home Depot (aka Rocket Depot) can speacial order Bondo Marine Epoxy. This is a One to One mix epoxy that is thicker than 20 min. finishing epoxy, but thinner than 30 min. epoxy. This stuff is far superior to that stinky polyester junk.

Ask your local home depot to order it, it costs about $12.00 a quart mix.

https://www.bondo-online.com/catalog_item.asp?itemNbr=275

The fiberglass cloth from Bondo is described as 8 sq ft I believe, is 6oz. glass. (I called Bondo tech support) This stuuf works great. It does however need to be veiled because it is very coarse.

Good luck

Johnnie Paul

thanks man I was thinking about doing that. The weave is pretty thick, it doesnt matter though because I am using it for internal.

When you say welled you mean coated with another layer of epoxy, or another layer of glass with a tighter weave.

Ryan,

When I say Veiled, I am referring to another layer of thin smooth glass like 2oz or lighter. A rocket buddy of mine has even used automotive primer to fill the weave, as it flows very thick. You could even use Kilz paint. Kilz is a paint used to kill mold or mildewed wall paint. It sprays on heavier than normal Rattle-can primer, and is very sandable...and very expensive, @ $3-$4 a can.

More epoxy just adds weight, the veil can be added when you apply the 6oz.

Johnnie Paul