PDA

View Full Version : fairing epoxy- the results



Dale R. Hamilton
05-18-2015, 12:17 PM
http://im1.shutterfly.com/media/47a5db39b3127ccee971de84910f00000030O01AZt3LRu4Zsg e3nwU/cC/f%3D0/ls%3D00203087497320150518170128415.JPG/ps%3D50/r%3D0/rx%3D550/ry%3D400/

Here 'tis. I know its the BOTTOM and once its turned over no one will ever see it again. But a slick bottom does mean speed- so I guess its worth a weeks time and lots of sandpaper and elbow grease.

Its shown in my paint booth- a large sealed room with a powerful blower pulling in outside air and forcing it through filters in the ceiling. Only was out is through that pit in the floor. That creates a downdraft envelope around the boat policing up any over spray, insects, dirt etc.

Ian McColgin
05-18-2015, 12:32 PM
Good set up and very nice job.

Dale R. Hamilton
05-18-2015, 12:36 PM
Thanks Ian- the paint booth really makes things easy. And anybody with extra space in the back yard can build one. I use it for boat storage when not actually needed- so it could serve as a garage.

DeniseO30
05-18-2015, 01:18 PM
Beautiful Dale! I expected nothing less! I do hope that is masking paper on the sides :( We did graphite on the bottom of a couple of canoes. looked great but I don't think it really made a big difference on rocks

slug
05-18-2015, 05:29 PM
Since you are going to great effort to produce a fair surface you might investgate postcuring to stabilize the epoxy and prevent future print thru and bumps

postcuring can be simple or complex. Ask your epoxy supplier for simple postcure advice ...it delivers the best bang for the buck . Be sure the epoxy supplier knows your building with wood core .

Dale R. Hamilton
05-19-2015, 08:57 AM
Since you are going to great effort to produce a fair surface you might investgate postcuring to stabilize the epoxy and prevent future print thru and bumps

postcuring can be simple or complex. Ask your epoxy supplier for simple postcure advice ...it delivers the best bang for the buck . Be sure the epoxy supplier knows your building with wood core .

Slug- I've never heard of postcure and I have not had epoxy failure. Can you explain?

slug
05-19-2015, 10:05 AM
Post cure...to fully cure the epoxy by raising its temp. Room temp epoxy never fully cures.

Im presently at sea with very little internet abilty so I cant find an article on the internet then post a link.

use google and ask a question like ...controling print thru by post curing ...or postcuring epoxy. West system, system three, Gurit, and perhaps woodenboat forum or boatdesign ney. will have a description of methods suitable for small home builders.

there is ton of info availble. A composite aircraft is post cured. Yout fishing rods are post cured.

be careful not to get overwhelmed with technical details of the post cure. Seek low tech solutions to raise the temp of the finished component and fully cure the epoxy .

the general boat yacht rule is to raise the temp of the laminate...fairing compound ... And primer system ....to the highest temp that the component...the boat...expects to encounter during its service life...perhaps 120 F. Then apply the topcoat.

a plastic tent and an electric heater or electric blankets are common.

slug
05-19-2015, 10:14 AM
I cant read the link so i dont know if its informative ... but try this

http://www.systemthree.com/sys3news/technicalresources/postcuring/

Dale R. Hamilton
05-19-2015, 12:46 PM
didn't see anything there Slug but will try google.

ulav8r
05-19-2015, 07:29 PM
Slug's link worked for me, just had to scroll down a page.

chas
05-19-2015, 10:20 PM
140 degrees, for four hours. Post curing epoxy technology in 1993. Not sure if there have been updates since then. You want to do this before final fairing. / Jim

paul oman
05-20-2015, 05:31 AM
what the article is talking about is epoxy curing agents that use a blend of curing agents (they all do) that includes ones that need higher temps to cure (often called high temp epoxies - relating to the tg issues in the article).

not an issue with 'regular' marine epoxies -




============================================
PAUL OMAN MS MBA Progressive Epoxy Polymers, Inc.
A.K.A. “Professor E. Poxy” -- "The Old Goat" -- "Epoxy Guru"
Epoxies since 1994
Member: NACE (National Assoc. of Corrosion Engineers)
SSPC (Soc. of Protective Coatings)
info@epoxyproducts.com 603-435-7199
www.epoxyproducts.com --- www.epoxyUSA.com
============================================

Dale R. Hamilton
05-20-2015, 08:35 AM
Thanks guys, I understand now but I don't want to go to the trouble. I've never had an epoxy failure. My cruiser which I built 15 years ago, with the same System Three epoxy is doing just fine.

http://im1.shutterfly.com/media/47b8ce39b3127ccec5309cb9446000000040O01AZt3LRu4Zsg e3nwU/cC/f%3D0/ls%3D00203087497320081018184535746.JPG/ps%3D50/r%3D0/rx%3D550/ry%3D400/