Glassing side panels: how much resin?

Welcome to PocketShip.net! This bulletin board is for builders of the Chesapeake Light Craft-John C. Harris "PocketShip" design, a 15-foot micro cruiser sailboat built from a kit or plans.

For more information on PocketShip, click here: http://www.clcboats.com/pocketship

This site gathers PocketShip builders in one place. Here you can share photos, tips, questions, and---eventually---your sailing adventures in PocketShip! CLC will also post design updates and tips here as they come up.

We'll try to knock down spam as quickly as possible.

Moderator: John C. Harris

Forum rules
Spam or commercial posts will be deleted.
This is a civil forum: no flames or drunken tirades.
Please stay on-topic.
PocketShip's Web Page: http://www.clcboats.com/pocketship
If you need CLC customer service: http://www.clcboats.com/forms/contact_us.html
We'll try to delete spam as soon as it appears.

Glassing side panels: how much resin?

Postby doug@dougbraun.com on Sat Dec 05, 2020 10:29 am

I've glued together the side and bottom panels, and I'm getting ready to put a layer of glass on the insides of the side panels.
How much epoxy ought I to mix up for each panel?
A more general question would be: how much epoxy is needed per square foot for fiberglassing?

I should have kept track when I fiberglassed the insides of the centerboard trunk, but I can't remember how much epoxy I used.

Thanks,
Doug
doug@dougbraun.com
 
Posts: 30
Joined: Fri Sep 25, 2020 2:47 pm
Location: Princeton, NJ

Re: Glassing side panels: how much resin?

Postby riverron on Sat Dec 05, 2020 12:42 pm

Hey Doug, I don’t think I have a definite answer. I would start with multiple smaller batches rather than one large one. You don’t want to apply too much where the glass starts to float. Also, you don’t want to waste epoxy like I did. I frequently mixed too much and had to throw away. I used the red solo cups and pretty much mixed the same size, which was about 1/4 to 1/3 of the cup. I mixed multiple batches to fit the job. I also mixed them for about 3 minutes to make sure they were mixed correctly. I had a clock on the wall that I used to monitor. Once I mixed and poured it on the glass, I used a yellow squeegees to spread and then rolled it until it was wet throughout. Let cured and did additional coats. The 2nd and 3rd coats will take less than the 1st.
Cold this time of year, so don’t forget the 60 degree minimum.

Hope this helps.

Thanks
Ron
riverron
 
Posts: 253
Joined: Fri Aug 07, 2015 10:29 am
Location: Richmond Virginia

Re: Glassing side panels: how much resin?

Postby doug@dougbraun.com on Sat Dec 05, 2020 11:18 pm

riverron wrote:Cold this time of year, so don’t forget the 60 degree minimum.


I have a luxury: I'm building the boat in my sunroom, which has its own independent forced-air heading system.
Normally over the winter we keep the temperature low and use it as a giant walk-in refrigerator, but while
I am building the boat I can adjust the temperature to whatever I need: keeping it cool as I apply epoxy
and afterwards turning up the heat to get it cured quicker.

Fortunately the sunroom has a big sliding patio door, so I can remove the boat when I it's finished. :)
doug@dougbraun.com
 
Posts: 30
Joined: Fri Sep 25, 2020 2:47 pm
Location: Princeton, NJ

Re: Glassing side panels: how much resin?

Postby SMHolmans on Sun Dec 06, 2020 2:26 pm

How fantastic to have such an ideal build location! My workshop is unheated and is currently subject to English winter temperatures i.e. cold!!!
SMHolmans
 
Posts: 125
Joined: Wed Sep 20, 2017 7:38 am
Location: Oxford, United Kingdom

Re: Glassing side panels: how much resin?

Postby doug@dougbraun.com on Sun Dec 06, 2020 5:34 pm

Well, I glassed one side panel. I used 880 grams of mixed epoxy, which is about 28 fluid ounces.
I had just enough - next time I might mix 5 or 10% more.

So according to my calculations, one ounce of resin will glass about 120 square inches.

For the second coat, I used 360 grams (or 11.5 oz) of epoxy, which was probably more than it needed.
For the third coat, I'll probably mix up 250 grams.

Doug
Last edited by doug@dougbraun.com on Sun Dec 06, 2020 10:28 pm, edited 2 times in total.
doug@dougbraun.com
 
Posts: 30
Joined: Fri Sep 25, 2020 2:47 pm
Location: Princeton, NJ

Re: Glassing side panels: how much resin?

Postby doug@dougbraun.com on Sun Dec 06, 2020 5:36 pm

SMHolmans wrote:How fantastic to have such an ideal build location! My workshop is unheated and is currently subject to English winter temperatures i.e. cold!!!

Even better is an understanding spouse. :-)
doug@dougbraun.com
 
Posts: 30
Joined: Fri Sep 25, 2020 2:47 pm
Location: Princeton, NJ

Re: Glassing side panels: how much resin?

Postby doug@dougbraun.com on Thu Jan 07, 2021 4:26 pm

Some more potentially useful trivia:

One pump of resin (with an almost-new pump) measured 8.6 grams.
The density of resin according to MAS is 9.5 lbs/gal, or 1.136 g/cm3.
So one pump's worth of resin is about 7.56 ml, or .255 fluid ounces,
and one pump of resin and hardener would be about 3/8 fl oz.

For example, if you want 8 fluid ounces of mixed resin, you would need
about 21 pumps each of resin and hardener.

One last statistic: based on the CLC's current prices for a gallon of resin and a
half-gallon of hardener, each pump (one of resin and one of hardener) that you do
will cost you 28 cents.

One last calculation (possibly the most useful): One pump's worth of resin and hardener
will be enough to apply a second or third coat to 158 square inches, or a bit over one square foot.
The first coat over bare wood will require more, and the first coat over class cloth will require
about three times as much.
doug@dougbraun.com
 
Posts: 30
Joined: Fri Sep 25, 2020 2:47 pm
Location: Princeton, NJ


Return to PocketShip Forum

Who is online

Users browsing this forum: No registered users and 3 guests