Electric Blanket for Epoxy Post Cure???

General Discussion
1

I picked up an electric heating blanket that was on sale at Sears the other day. Any helpful tips for getting an even temperature for a post cure? Should I pre-wrap the board with a regular blanket or something under the electric blanket to help evenly disperse the heat from the electric blanket's coils? I'm planning to tape a thermometer against the glass under a coil to make sure i don't get over 110F.

I'm using RR CE over unsealed Marko 1.9 blanks, no vents.

Or is the electric blanket just a bad idea in general?

Thanks!

2

Don’t know about the electric blanket, but I built this oven for $60 and was able to maintain 110* F pretty easily. Stuck 2 cooking thermometers in the side of th RMAT; one up high and one down low. The one up high read 120 deg and the one down low 110 deg.

3

Rickter

You are on the right  track. Pre wrap, Start with the low setting, monitor temp and put in a board bag.

CJ

4

Tommy - That's a nice looking oven. Soon, I hope to have enough space to build something like that. Is your board propped up on anything or just resting on the bottom?

CJ - Appreciate the reassurance.Throwing it into a board bag sounds like a great idea.

Thanks guys!

5

I would think you could just form a tent type thingy and slide the board in it

are you baging it? or just regular layup

6

Hey Rickter

I've used an electric blanket to warm up a board in a vacuum bag that was in a garage in winter. Warmed it up to abut 20*C, enough for the resin to go off, but not to post cure.

K

7

i melted a big section of an eps board using an electric blanket. it had a short or something it was reallyhot in one area of the blanket

8

I love [color=black]Electric
Blankets[/color] and i use it often in the cold weather. but i only use preheated blanket.

9

Seems like a good idea until you try it which i did twenty years ago.  The uneven heating caused the foam to gas and the board ended up looking like a puffer fish.  Back then a very costly experiment.  But hey giver a go and keep me informed.  Tommy has better way, and consitent. The resin systems have improved  so much since then.   A good low tech option, for the finacially challenged is inside a dark colored vehicle in the sunshine, but beware of excess humidity which can cause even the best resins with cycloaliphatic hardeners to blush.  Oh and always watch out for outgasing which can cause problems, and Tommy mentioned the magic temp of around 110-20.  Hey you can always put it in the bag and post pics… Good times.

10

"I'm using RR CE over unsealed Marko 1.9 blanks, no vents."

Post cure not required.

E-Blanket = Bad idea.

Oven = overkill.

I can rant all day long on this stuff. Lam and hot coat in less than 24 hours. Shop temp aprox 70-75 degrees F. Let surfboard sit for 5 days......Garage builder....I read all of Gregs posts.............

I don't use a scale to mix RR epoxy. I build surfboards not spaceships.....Solid ,strong, boards....

Ray

11

Christ ! for the past few days the shaping shed has been 37- 40 degrees (~100F) with the doors closed from 8am to 8pm, courtesy of our Australian summer and no curtains on the windows.

 I dont measure the exact temps or times but fresh epoxy seems to get harder and crisper after a few days in the shed.

 

12

Rickter

For what it is worth, 

I tried it once and it was succesfull. the surfboard was wrapped in several blankets.

But as ray says: you dont need it if you build a simple surfboard.

Cheers