Fiberglass mat and polyester resin

[secondchance22107]

I am not sure if i am doing this right i am wetting out the mat on the piece i am working on in this case the transom,while putting it on the fibers stick up and come apart on the brush....after curing i have to sand the the sticking up fibers and smooth out the mat so it will be smooth .....i am doing it right or wrong....i am dabbing it out with a 1" brush when putting on the resin .... thanks LeRoy

 

[sphelps]

Re: Fiberglass mat and polyester resin

Are you laying up a small or large piece of csm ? A short nap 4 or 6 inch roller will make things much easier . I would also suggest you use a bigger brush than a 1" . You can get a box of 2" chips brushes at H/F pretty cheap . Cut about a 1/2 " off the bristles . It will make a lot of difference working air bubbles out ..

 

[tpenfield]

Re: Fiberglass mat and polyester resin

resin roller would be good for you . . . a brush is going to make a mess with CSM . . . but you know that.

I usually try to have a flat area where I can do an initial wet out of the CSM and then I transfer the piece to the desired place on the boat, etc. and do the final wet out.

another way I have done things is to 'paint' (more like slobber) the resin on the desired area with a brush and then apply the CSM dry and roll it out so the CSM sucks up the resin and wet out.

 

[Woodonglass]

Re: Fiberglass mat and polyester resin

Glassing 101...Always fill any voids in the piece you are glassing. They will cause air pockets if not filled. Always pre-coat the wood with resin and wait till it tacks up a bit and then lay the CSM on the tacky coat. Using a bubble roller to smooth it out at this stage helps a lot. Then pour the resin in the middle of the piece and use a short nap 6" nylon roller to roll the resin from the middle out towards the edges. Don't use to much resin and don't roll to long just enuf to get the resin distributed and allow the mat to go clear. Then finally use the bubble roller to work out any problem areas. Dabbing with a brush works well for corners and edges but not so much on large flat areas.

Are you glassing on a horizontal or vertical surface?

 

[secondchance22107]

Re: Fiberglass mat and polyester resin

i was glassing on vertical .....i tapered the plywood with is two 3/4" each so it was rounded instead of sharp corners... i have been reading another thread on here and woodonglass you put a post with an address about not using pl and use tite bond instead...can you explain to me why i have read on here and i used pl to bond my transom together....i also had put some polyester in a gallon jug one simular to a oblong milk jug and the resin gelled in the container any ideas on that ... i had taken it out to the 5 gallon can to make it easier to pour when needed... also when i tried to get to the site you put up it wouldnt let me go there the reason i am asking.

 

[Woodonglass]

Re: Fiberglass mat and polyester resin

What kind of resin are you using? Where did you buy it? Sounds like the Resin is bad. If you did not add the hardener it should not gel at all. PL can be used to glue the transom. It's just that it takes it 72 hours to totally cure and I don't like to wait that long. Using Titebond III wood glue allows you to glue it up one day and install it the next day. Resin and Hardener should be mixed at a 1.5% to 2.0% ratio by volume. It's easier to use the metric system so if you do that 1000 milleleters of resin would use 15 to 20 millileters of Hardener. In cool temps (below 80? F) this ratio will give you about 15-20 mins of working time before the resin starts to set up and get tacky.

 

[tpenfield]

Re: Fiberglass mat and polyester resin

Yea, if you activate a gallon or so of resin and keep it in the bucket for 5 minutes or so, it is going to gel/harden prematurely because of the heat that gets generated.

it sounds like you may be treating the resin more like paint than plastic.

If I need extended working time, I cool the resin beforehand. . . But even then, it is important to apply the resin to the glass quickly.

 

[secondchance22107]

Re: Fiberglass mat and polyester resin

thanks for the info ..... i did not put hardner in the one gallon bucket it was to pour in a measuring cup....i am using the metric system i bought a childs syringe with the metric system on it....i am only mixing 4oz and 8 oz at a time on these projects i guess i am too slow cause if i mix more i run out of time and it starts to harden using 1 cc for 4oz....now when i install the transom and get ready to install the stringers do i butt up the stringers directly to the transom or do i pb the stringers with a little space so it doesnt touch the transom...i have read but not sure of this..readp opps one totally and frisco one and many others i read every night and enjoy reading others projects....i really appreciate this site more than all the others i go to together....thanks everone for sharing your experiences....i bought the resin from online compisites in a 5 gallon pail with the product and shipping it was 182.00....it only gelled in the 1 gallon bucket i poured it into it hasnt gelled in the plastic container i am using now.....i do keep a lid on it when not in use...i do have pictures of this project here of the restoration.....Photo and image hosting, free photo galleries, photo editing | Photobucket

 

[Woodonglass]

Re: Fiberglass mat and polyester resin

1 oz per 4 oz is a 2% ratio. That will make the resin harden fairly quickly. You can cut it back to 1.5% ratio with no adverse effects and it will give you more work time. Where R U located? What are your temps?

 

[secondchance22107]

Re: Fiberglass mat and polyester resin

i live in madisonville,la. and the temps are 45 to 50 in the mornings and the 60 to 70s in the evening.....i wait till the temp gets above 60 before i start with the resin actually more like 65 ....here is a picture of the bubbles ,,,

i sanded all the work on the edges off today and will try to do it over tomorrow or friday..... i have a roller and a corner roller but i dont see what they do when i use them i dont see any difference in the way it was before i used them....

 

[secondchance22107]

Re: Fiberglass mat and polyester resin

the rollers i am talking about is the 3" alum. resin roller....dont know the proper name for it sorry.

 

[Yacht Dr.]

Re: Fiberglass mat and polyester resin

1 oz per 4 oz is a 2% ratio. That will make the resin harden fairly quickly. You can cut it back to 1.5% ratio with no adverse effects and it will give you more work time. Where R U located? What are your temps?

I think you mean 1CC per 4 OZ .. ..

the rollers i am talking about is the 3" alum. resin roller....dont know the proper name for it sorry.

The plastic bubble rollers are better then the alum rollers IMO .. flush them out with a good clean acetone wash.

YD.

 

[secondchance22107]

Re: Fiberglass mat and polyester resin

thank you yatch dr. can you tell me what i am doing wron with the picture i posted...... i agree i have already had heck cleaning the alum. one will be more than likely get a plastic one soon....the corner one is plastic...

 

[JASinIL2006]

Re: Fiberglass mat and polyester resin

secondchance, I did my very first wet out of CSM on my replacement transom today. When I first wet the CSM with the poly resin, it looked great. After I did the whole piece, I went back to where I started and I saw all those little bubbles, too. I just went back and forth over them with a little 4" bubble roller, over and over until they were gone. It took quite a while. I don't know if I missed them when I first wet out the CSM or if they actually appeared after a bit, but the trick seemed to be to move slowly with the bubble roller. I think I was able to get most of them out, but it really took a while.

Good luck,
Jim

 

[secondchance22107]

Re: Fiberglass mat and polyester resin

thanks jim, i tried to stip with a brush but it was pilling the matt apart..... was your starting to set or still soft when you did it .... i am going to try again tomorrow..... i sanded most of them and going to put fresh coat of polyester tomorrow let it tack and then try to put more mat on it...i was hoping to be putting the transom in the boat this weekend but unles i can figure this out i dont see it happening... i have a lot of sanding left to do before i can even think about putting the srtingers in its about 3/8" thick in fiberglass on either side where the stringers were........ LeRoy

 

[JASinIL2006]

Re: Fiberglass mat and polyester resin

Hi Leroy, sounds like we have the same plan... I'm trying to get the transom in and use up a 5 gallon pail of resin before it gets too cold to work outside.

When I first noticed the bubbles the resin was still pretty soft, but I worked with it until it started getting a bit sticky and gelled. I probably spent 45 minutes just working the bubble roller.

Good luck and I hope you get lots done this weekend.

Jim

 

[jbcurt00]

Re: Fiberglass mat and polyester resin

When I first noticed the bubbles the resin was still pretty soft, but I worked with it until it started getting a bit sticky and gelled. I probably spent 45 minutes just working the bubble roller.

45min of just working it w/ a bubble buster sounds like an exceptionally long time when you add in the mix time, and the time actually laying the glass & resin out before you stared w/ the bubble buster...

As long as it kicks off, I guess you're good.

 

[JASinIL2006]

Re: Fiberglass mat and polyester resin

It was getting cool in the garage -- just about 65 degrees Fahrenheit -- and I mixed the resin so it wouldn't kick fast, since I'm just learning. I just checked on it and it seems OK.

Jim

 

[secondchance22107]

Re: Fiberglass mat and polyester resin

Happy thanksgiving to all...

 

[secondchance22107]

Re: Fiberglass mat and polyester resin

here is a photo of where the stringer on the starboard goes after i sanded where the other one goes on both sides there was at least 3/8" of glass hopefully i am doing this right by taking that much glass off where it was

this is what it looked like before i sanded it this is the port side

now can anyone tell me what this black stuff is its like a rubber and only in certain spots on the hull does it need to come out or just leave it alone

now one more question keeping in mind that this is the bow and the foam was stuck where ti water is standing forward.....should i pb this so if water does get in there it wont be able to stand like it is now