ardrhi

Hello Everyone,

I need your advice. [8D] I am looking for my best option, with a top quality epoxy. Has anyone had experience with the West Systems line? They seem (from my limited research) to be a very high quality resin, and a much better alternative than your "run of the mill" hobby line. How does their finishing resin/hardener ( I think it is 207 ) compare to say, Z-Poxy Finishing resin? How is it's workability, sandability, hardness (Is it properly rigid as finishing resins should be?), and clarity? With this warbird project, it is worth a little extra dough, to enjoy the satisfaction that comes with quality. [>:]


Thanks for all your help!

Chris

"It is better to burn out! Than fade away....."

Ed Smith

If you want a reliable consistant top quality resin then do not use the hobby store products. West Systems products are top of the line products. HOWEVER, working time/pot life has to be considered. West slowest hardener will give no more than an hour before the resin starts to go gummy. For this reason I do not use it.

I need a longer pot life for most of my projects. I use MGS resin, it has the same quality as West. MGS has two hardeners a twenty minute pot life and a five hour pot life. They can be mixed to a pot life of your choice.

207 is a hardener not a resin.

Go here for more information:- http://www.westsystem.com

Ed S

ardrhi

Interesting. I will have to check out MGS for the Finishing/Glassing. I appologise for not being clear. I am aware that 105 is their Resin, and 207 is the hardener. Didn't mean to confuse the issue. Is it possible to use the 207 for external glassing and extend the pot life of it with DENATURED alcahol? As I understand rubbing has too much water to be of use, and weakens to structure.

Chris

Ed Smith

Another golden rule. I never thin epoxy with anything. Thinning alters the properties of the cured epoxy. Some epoxies will not fully cure, they stay rubbery.

A lot of people do thin epoxy and say that it has no adverse effects.

Read the West website it mentions thinning.

Ed S

daven

My Feedback: (1)

My preference is Easy Lam 60. Takes close to 24 hours to dry hard, but I like the extra working time. It is also quite thin, which makes it easy to work with, without thinning.

TeamSeacats

I use West Systems quite a bit and I can't imagine a scenario where the slow hardner doesn't give me enough pot life (5 hour pot life!? What are you building!?). You'll also note that, at least for West Systems, the fast hardner will make for a stronger cured epoxy than the slow. Never thin epoxy with anything as it will seriously alter it's chemical makeup. Polyester resins can be thinned up to 10% with MEK or Styrene but anymore than that and you start altering their properties as well...but they are usually thinner than epoxies to begin with.

207 Hardner is not fully intended for laminations - it does give the epoxy a little better wetout but it's really designed to give the epoxy some UV resistance. I would still use the 205 of 206 hardner unless you are trying to clear coat wood with it.

Ed Smith

I do not necessarily need five hours pot life, it is about the maximum MGS slow hardener will give you. I mold my own fuselages. I join them in the mold while both sides are still wet. It is a three hour process. With some of my fuselages I add details (Firewall, wing mounting blocks, etc) all that takes time. Hence my preference for the slow hardener. I also mold carbon props. It is a one hour process. I mix the two MGS hardeners for a shorter pot life. So for me there are plenty of scenarios where variable pot lives are important.

Ed S

TeamSeacats

Ed,

I can see that - I would be very interested in how you join your mold halves in the mold. Are your molds closed or do you have access holes to get to the interior (perhaps where the cockpit might be)? Sorry for the thread hijack.

Jake

ardrhi

Jake/Ed,

*laugh* This is all great info. However, I have a few questions for both of you: Since I don't need extreme pot life. (As with moulding products, as Ed stated.) The most extensive glassing I will be doing, (besides structural) will be fiberglassing of sheeted foam cores. Should I stay with West Systems for quality? Also, everything I have read, states that there is a huge difference between a Finishing Resin, and regular hardeners or resins. Is West Systems a bad choice for glassing a wing? Doesn't that make using 205 or 206 a bad choice? Why is 207 not a good choice? (Per Jake's prior post.) Don't they state that it is intended for glass work? *Confusled*


Chris

dreadnaut

My Feedback: (5)

I use West System for most things, but when I need a thinner resin I use Pro-Set. It is more expensive, so I only use it where the application calls for a lower viscocity.

Do not thin the resin with alcohol.

TeamSeacats

Product information for 207 from the West System website:


http://www.westsystem.com/webpages/e...ct_207804.html

I couldn't find the mechanical strength properties of the 207 anywhere, but I would suspect that there is a tradeoff for using it vs. one of the more standard hardners. You probably lose some strength in the epoxy in return for the clarity and UV resistance.

Atlanta 60

My Feedback: (18)

Man..I'd love some details on this as well!! Funny..I've been kinda dreaming of both adding details/joining the fuse while wet and doing props myself...I havn't yet decided I could do it though...Great to hear it's possible!!


As to West Systems...I'm pretty slow by nature...I normally bag all my stuff too which adds some time...I've not had any trouble with West Systems 105 and the 206 Hardner...I like it fairly well...

I also like PTM&W AeroPoxy...Especially for Arimid Fibers...

Have Fun...

Chuck

Ed Smith

My Goodness, so many questions. I have a big one on my Private Mail as well that I have to get to. I will try to stay on topic.

However, Jake first.

With all of my fuselage molds I can get in through the wing saddle. With some of the molds I have acces through the nose ring hole, I have opened up the mold there (I think it is called foresight). With all of them it involves the brush on a stick thing to reach inside,
especially at the tail end.

Chris,

I guess it is a question of how much glass work one does and how long each individual process takes. In my case when I glass a wing I apply all of the glass at the same time. That is various layers of centre section glass and the whole wing, both sides at the same time. I then vacuum bag the wing. It takes longer than an hour to do all that. I do a lot of glass work so I purchase resin by the gallon. I use the same resin for everything, gluing on wing skins, finishing, making molds and parts.

In your case I would recommend West 105 resin and 206 hardener as a good general purpose combination. I do not use hobbystore resins, the quality always seems to vary. But then that may be just me.

Ed S

TeamSeacats

Ok, I was hoping for some magic bullet to seal up the two halves inside a closed mold without having to cure, trim, reinsert, bond or make a mold strong enough to withstand an internal air bladder....Thanks for the info!

Atlanta 60

My Feedback: (18)

Internal Air Bladder was the route I was thinking as well...lol

Kevin Matney

My Feedback: (1)

Try [link=http://matneymodels.com/accy.html]Skin It Epoxy[/link]
Skin-It Epoxy
Laminating and Finshing System

Skin-it Epoxy is the best long cure low viscosity adhesive you can ever wish to use. Skin-it works great with both balsa and glass skins, and is perfect for vacuum bagging. Skin-it also makes a marvelous finishing resin that sands very easily. It is a must to help you get the show plane look you want. Pot life is 30 minutes, giving you time to make adjustments. The mix rate is a 4 to1 but is very forgiving.

I have thined Resin with 90% alcohol the good stuff. The 70% will look white