Model Boat Mayhem

Mess Deck: General Section => Model Boating => Topic started by: Anchorboy46 on June 08, 2009, 01:13:20 am

Title: It hasta dry...
Post by: Anchorboy46 on June 08, 2009, 01:13:20 am
Just come up from the welding shop,after glassing the bottom and sides of my Cal -
Tex Lumba Lumba.
 Seems previous builder left a very rough surface with looks like fiberglass resin and then grey primer sprayed over that. After sanding with 100 grit for 2 days, I figured it was time to add some strength to this beast.
 Starting with some light 4 0z. cloth i proceeded to cover the bottom and sides,being careful to cut out for the installed stuffing tubes and prop shafts.
 I used a "Its not butter" butter cup and filled it with the polyester resin about halfway. Maybe 8 oz at the max.
 Being that it was 95 degrees out and I was soaking my undies, I added 8 drops of catalyst and began stirring with an ice cream stick. I laid up the cloth to the boat and cut the corners and head stem on the keel.
 I applied a rather thick layer to the cloth dabbling as I went to get out the air bubbles. I finished in a bout a half and hour and there was a little resin left in the bottom of the butter cup and it still hadn't kicked yet... GAWD I hope this stuff kicks!!.. I'm gonna go back down there in an hour or two- WISH ME LUCK! Anchorboy
Title: Re: It hasta dry...
Post by: tigertiger on June 08, 2009, 02:34:12 am
I have a feeling poly-resins need to be in an airtight environment to set. I.E.wrapped in a plastic bag.

But I could be wrong.
Title: Re: It hasta dry...
Post by: andygh on June 08, 2009, 03:06:25 am
Correct, you are completely wrong  :D
Title: Re: It hasta dry...
Post by: tigertiger on June 08, 2009, 05:04:06 am
OK so what resins need to be set in a non-air environment?
Title: Re: It hasta dry...
Post by: toesupwa on June 08, 2009, 06:08:35 am

Starting with some light 4 0z. cloth

Being that it was 95 degrees out and I was soaking my undies, I added 8 drops of catalyst and began stirring with an ice cream stick. I laid up the cloth to the boat and cut the corners and head stem on the keel.
 I applied a rather thick layer to the cloth dabbling as I went to get out the air bubbles. I finished in a bout a half and hour and there was a little resin left in the bottom of the butter cup and it still hadn't kicked yet... GAWD I hope this stuff kicks!!.. I'm gonna go back down there in an hour or two- WISH ME LUCK!

4oz cloth is HEAVY... 0.75oz is light..

If your Mix doesnt go off in less than 20 mins (especially in 60+ degrees) then i suspect you will be waiting a week for it to set...

Check the 'butter cup' to see if the remains of your mix will (if ever) go off....
Title: Re: It hasta dry...
Post by: Anchorboy46 on June 08, 2009, 06:27:21 pm
Well,well, a California man! I was originally from Oceanside,Ca. but moved here to Crockett,Texas. Obviously, you haven't been down here in our heat! I didn't go down there last night, but preferred to go in this morning. To my delight, the butter cup kicked off and the throwaway brush was stiff as a board. 99% of the boat is dry just a little tacky around the edges.
 I cut off the excess cloth edges while it was still in a somewhat tacky condition. Tomorrow I will give the hull a "hotcoat". Then after a week or so, I will sand the dickens out of her! Model Boat Building! Isn't it a gas! Anchorboy
Title: Re: It hasta dry...
Post by: andygh on June 11, 2009, 10:04:10 am
Quote
OK so what resins need to be set in a non-air environment?

Dunno but all the polyester or epoxy resins that I've ever used have been fine in the open air
Title: Re: It hasta dry...
Post by: oldiron on June 11, 2009, 11:29:09 am
 As another suggestion, instead of "daubing with a brush" when applying the resin over the cloth, use a hard surfaced paint roller. Professional large boat builders use metal rollers to smooth out the resin/cloth mix. This removes air bubbles and leaves a relatively smooth surface that requires little sanding.
  Don't use a fuzzy roller. I've used the foam throw away jobs with great success.

John
Title: Re: It hasta dry...
Post by: tobyker on June 11, 2009, 11:30:20 am
I wonder if you're thinking of those masts that people laminate and coat with epoxy resin and then vacuum bag?
Title: Re: It hasta dry...
Post by: Martin (Admin) on June 11, 2009, 12:04:32 pm
Quote
Maybe 8 oz at the max..... I added 8 drops of catalyst


Is that the right amount? Sounds quite a high ratio.
How about making up a small test mix at a higher ratio?
Title: Re: It hasta dry...
Post by: Wasyl on June 11, 2009, 12:18:52 pm
OK so what resins need to be set in a non-air environment?
Cannabis Resin,perhaps %% {-) %%

Wullie
Title: Re: It hasta dry...
Post by: gondolier88 on June 11, 2009, 02:26:05 pm
Hi,

TigerTiger, you may be getting confused with cyanoacrylates- superglue to you and me- which has to be void of air if it is to set.

Greg

Title: Re: It hasta dry...
Post by: steamboatmodel on June 11, 2009, 02:41:25 pm
OK so what resins need to be set in a non-air environment?
The big boat builders use a vacuum bag system to get the air bubbles out of the resins and materials. The resins will set with or without air.
Regards,
Gerald.