Preferred epoxy

[Rick Wright]

I'm new to this group and just beginning to figure things out about building.  I have search the forum but have not found what the recommended epoxy is for building an ez.  I have found information that is years old but nothing current.  Thanks in advance for any help.

[Stefano Ferretti]

I've finished building my new VariEze, here in Italy, in 2011.
I employied only MGS 285 epoxy resin ( hardeners: 285 - 287).
It worked flawlessly!
Stefano

[BruceHughes]

Hi Whoever you are (it is nice to sign your emails...)

I am NOT recommending anything, in case any lawyers or engineers are looking.   My project was built, almost entirely, before I
bought it.   They were using Ez-Poxy, I think.   The color looks like Ez-Poxy.   If I have to trim anywhere, it smells like Ez-Poxy.

I bought Aeropoxy for the few jobs that I did.   It is a good, structural, epoxy.  I like it.  Smells good.  Others may know of something
better, but I doubt it.

West System epoxy is used TO SMOOTH THE SURFACE.   There is more than one type of hardener depending on the temperature at
the time that you are working or the temp. inside your shop or how much of a hurry you are in.  There may be another type of epoxy carried by G. Brothers that is structural BUT do not confuse the two.   The trouble with West Sys is exotherms.   You mix in SMALL quantities and stir and stir and stir and GET IT ON THE SURFACE AND SPREAD.   You will ruin a few batches before you find out how
to work with it.   Another trouble: all of that stirring puts bubbles in the epoxy which then create pinholes.   Once I had to build a
new aileron (first one was too heavy) and paint it.   The paint company recommended cleaning with a certain product and it is a
good organic solvent.  It went right through the pinholes and destroyed the foam underneath.       Had to build another one.

Bruce Hughes   



Bruce Hughes (NOT an engineer - I am a Microbiologist)   

[mattstecher]

This is something I know a little about so I thought I would respond. I have used MGS, West System and EZ Poxy.

MGS is what I started with and it wets out great and the pot life can be adjusted by mixing fast and slow hardener as required. But I soon developed an extreme allergy and had to stop working with it.

I then moved to West System 105/209, it also wets out well, but I only get about 30 minutes of working time. As long as you get it down before it starts to gel you are fine and follow on lay ups still develop a primary bond as long as you get the next one down when it's still tacky. You can also get nice and short cure times with the quicker hardeners on small jobs so you can keep moving forward.

I use EZ Poxy 10/87 for long layups that I am not in a hurry for and for all fuel tank work. It's a little more work to wet out glass, but just keep it and your workspace warm.

All the approved resins (Gary Hunter's work is published everywhere) are fine for primary structure laminations, West has proven to be the easiest to finish with, and EZ Poxy for chemical resistance. You really don't need to post cure anything except for fuel tanks.

It's also a major pain to weigh or balance all your batches so use the pumps. West has these cheap and they even fit the EZ Poxy resin and hardener cans,

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you just have to include a spacer on the resin pump to reduce the volume dispensed with each push and get the proper ratio.

For safety sake I always wear nitrile gloves and if I can smell the epoxy I use a respirator. Fresh air really helps so I have a fan pointed at me and can usually work without one.

I don't bother with vacuum bagging, but have used the Cozy Girrrls lo-vac method to help a part hold its shape during cure.

Fly safe folks,
Matt Stecher
Katy, TX
Varieze N54EG rebuild
Cozy4 chapter 11

[Marc Oppelt]

Pro-set. Nice to work with, no noxious odor, and cures up really strong.

Search for a post w/ details on a group discount.

[dorr]

Why not ask this question of an Epoxy Engineer - each Epoxy has different qualities in terms of strength, etc.  I'd hate to find out my epoxy is half as strong as EZ-Poxy which has been tested by Rutan...:

HUNTER, GARY A. 117 Mesquite St. Lake Jackson, TX 77566 281-433-8478 lucyliu22@mac.com