boater

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Some racing model boaters use this resin, Resin Research Epoxy 2000 w/ 2100 fast Hardener, supposedly almost as hard as MGS but without the high pricetag or shipping. Was developed as a epoxy replacement for polyester in polystyrene foam surfboard fabrication. Talking to an epoxt salesman, he said most fast curing systems will be harder than slow curing systems because of more crosslinking. YMMV

From Fiberglass Supply, Washington :: We are now stocking Resin Research Epoxy. It is a 2:1 ratio room temp. Cure epoxy that is water-white. Resin Research Epoxies are specially formulated for building surfboards but are also suitable for other applications where a clear finish is desirable and the need exists for an epoxy that exhibits good UV resistant characteristics. As with most epoxies its properties will greatly improve by post curing the part.

Also avail in other parts of the country and world -- visit their web site.

wyowindworks

I've done quite a bit of test with Resin Research Resins. Post curing does nothing to improve the resin. The low viscosity is great but the Tg (softness at elevated temps) is worse than most. MGS is king and worth the extra dough. The shipping for the fast hardener (H285F) doesn't require hazardous material charges....at least from Aircraft Spruce. The fast is suitable for most modeling procedures. My next favorite is Adtech 820. The issue with that resin is that it turns some IMC clears (In Mold Coatings) hazy. It will also dull mold surfaces treated with semi-permanents for some reason. For that reason I did almost all my production work with MGS L285/H285F. USC635 has a lot of bang for the buck but I a little too viscous for high performance applications. It will cause some IMC's to turn tacky and never polish right after demolding.

wyowindworks

I've done quite a bit of test with Resin Research Resins. Post curing does nothing to improve the properties. The low viscosity is great but the Tg (softness at elevated temps) is worse than most. MGS is king and worth the extra dough. The shipping for the fast hardener (H285F) doesn't require hazardous material charges....at least from Aircraft Spruce. The fast is suitable for most modeling procedures. My next favorite is Adtech 820. The issue with that resin is that it turns some IMC clears (In Mold Coatings) hazy. It will also dull mold surfaces treated with semi-permanents for some reason. For that reason I did almost all my production work with MGS L285/H285F. USC635 has a lot of bang for the buck but I a little to viscous for high performance applications.

boater

My Feedback: (2)

Adam, I believe you tested the RR 2070 resin, please examine the specs for the 1980 and 2000 resins. http://www.resinresearch.net/id2.html Resin 2000 is supposed to be harder than polyester!! A copy from Graphite Master's Webpage on RR2000 resin::"The Resin Research Surfboard Epoxy is available in three styles. The original 2000 Epoxy system (clear), the CE Epoxy which has an optical brightener (bluish tint) and a UV inhibitor, and the newest Kwik Kick Epoxy which looks like the CE but goes off quicker and becomes harder faster than any other surfboard epoxy on the market. This Epoxy system was developed by Greg Loehr and has many benefits; it is extremely easy to use, dries harder than Polyester, can be used on Polyurethane blanks, and is odorless. You must mix at a 2 to 1 (epoxy to hardener) ratio, also mix thoroughly. You must mix at a 2 to 1 (epoxy to hardener) ratio, also mix thoroughly. 1 Quart of RR Epoxy."


Yes, I agree MGS is KING.

I'll confess being the choice of surfers doesn't usually buy alot of respect from the aerospace crowd.

boater

My Feedback: (2)

Some may find find this PDF informative:: http://graphitemaster.com/wp-content...tion-Guide.pdf

wyowindworks

Rudy, I never tried the 1980 and 2000 resins because their manufacturer specs are lower (HDT, Flexural Modulus, and hardness) than the 2070 that I tested. I also played with their slower hardeners for the 2070 which performed even worse. Post Curing did nothing to improve my elevated temp deflection tests.

Take a look here. Lower HDT, Lower Modulus, Lower or equal hardness
http://www.resinresearch.net/id8.html

Also, the Resin Research 2070 resins stick to semi-permanent mold releases. I can't comment on their other resins.

84 Barcol hardness is pretty low. I think MGS is 92...going from memory.

wyowindworks

For those who are using USC 635: The medium hardener really benefits from some elevated temperature curing. It's mandatory with the slow to get it perform well.

Pylonracr

Thanks for the info Adam. I use the USC 635 a lot, and I use all three hardeners.

Scott

MTK

Many of my landing gear are laid up with the 635 and medium hardener. USC epoxy takes its time reaching full performance. I've found it slower than others but it eventually gets there. Definitely agree post curing helps. I use 170 for 24 hours usually but maybe higher temp is better/quicker; I just don't have the capability in my shop.

RAPPTOR

My Feedback: (41)

Been using 635 for a few things. glassing wings.. been using gram scale to mix.. called usc .. STEVE , said 100 to 32 mix by weight.
less hardener for, stiffer cure.,had a few 3 to 1 mix, stay rubbery for few days.. humid as all hell here.. 100 degrees

Pylonracr

All 3 hardeners use a different mix ratio. Epoxy must be mixed accurately for proper cure. Who ever told you to use less hardener did not do you any favors. I also use a gram scale to measure and have never had a problem with the cure of any resin I have used.

MTK

I didn't intend to imply that there was something wrong with the USC635 epoxy systems. There is nothing wrong with it in my opinion and is very reasonably priced with simple shipping requirements. It cures well but takes a little longer to reach full cure than some other systems. Once it's there, it's there for good. I too use a gram scale which measures to 1/10 gram. Good mixing is a must for any two part system, be it epoxy, urethane, ester whatever have you.

RAPPTOR

My Feedback: (41)

THANKS FOR INFO.
I think im getting blush so humid. so hi

T_om

ADTECH 820 (my favorite resin) has acceptable Tg at room temperature cure but does MUCH better when cured at elevated temperatures.

Not to talk down to people or insult anyone, but you need to understand exactly what "Tg" means. It is the "Glass Transition Temperature" and is the temperature at which epoxy ceases to be "hard" and starts softening and becoming more rubbery. Tg actually represents a range of temperatures but for simplicity just think of it as the temperature where you start losing all the great characteristics of epoxy and begin having problems.

All quality resin manufacturers will post the Tg in their specs. And almost ALL resins Tg benefit from elevated temperature cures (hot box for example). Cliff Notes version: You can not get the best Tg from any epoxy without heat curing. ADTECH for example recommends 150 degree F post cure to maximize Tg and hardness.

Most epoxies Tg value when cured at room temperature is about 135 degrees F. Easily reached under darker colors sitting in the sun (especially the Florida sun where I am located) or in a closed vehicle. Post curing elevates this 40 or 45 degrees F... a BIG difference.

Hope this helps explain things a bit.

Tom

RAPPTOR

My Feedback: (41)

THANKS. I think I build hot box. it will help in all areas. I thought-TG- was a HARDNESS SPEC.. DAH

Hydro Junkie

When you jet guys start talking about West Systems, you are forgetting one simple piece of information:
West Systems is made for marine use where some give is a requirement.
If I started building racing boats using the rigid epoxies you are all crowing about, the boats would fall apart before the end of the season due to the epoxy joints failing from the continuous pounding they take running at their 50+ MPH speeds. Another advantage of West Systems, for boaters anyway, is that if a piece of skin is damaged, it can be removed by heating up the joints without damaging the rest of the boat. At that point, you only need to replace the damaged part and attach with more West Systems.

MTK

Marine epoxy for sure for the boats then. It has a softer cure. Plus it's inexpensive. The money they wanted to charge for Adtech is best spent elsewhere

T_om

Huh? ADTECH is about the same price as WEST... but whatever blows your skirt up.

Tom

boater

My Feedback: (2)

I'm a boater, too. The harder laminating resins like MGS are preferred for building light, thin fiberglass or carbon layups and obtaining a fuselage or wing that isn't too rubbery. Many boaters prefer a hard resin like MGS or vinylester or polyester to layup a mono or cat and not have it flex so much it wouldn't run right. There is a discussion here:http://www.rcgroups.com/forums/showthread.php?t=2421351 that talks about the differences in a laminating resin and an adhesive resin. An epoxy that is strong, yet with some flex makes a better resin for joining birch plywood for a hydro's body. We probably agree that instant glue makes a poor choice for joining birch plywood either in a boat or a firewall that takes a beating being that it is sooooo brittle like glass.(there are some wood hydro builders that proclaim that a transom glued in with instant glue will cleanly fail in a rudder strike!) But you may also find that some of these "harder" resins that make a poor adhesive make a great laminating resin whether for a mono or a glider or a pylon racer.These glider guys are light years ahead of boaters when it comes to light AND strong. You may also find the harder resins to be an easier resin to surface finish plywood boats with, cause they don't cure so rubbery and are a bit easier to sand (but that's splitting hairs).

RAPPTOR

My Feedback: (41)

YEP .. so far. about 40 mixes. 635 has been good. even when I mess up mix, 3 to one or 32 % to 100. still gets hard. takes longer, but still gets there. very thin and works well on carbon

MTK

The girl I spoke to gave me a high price. She also said it doesn't come in small quantities (1 pint-1qt) that I wanted. If there is someone else I should speak with, then state that... . We're having a friendly informative discussion and you have to get nasty....Geesh get a life

T_om

Since I see no point in buying thimblefuls of epoxy, gallons are fine with me. I have no idea what "girl" you spoke to. Was she a grade schooler? Pre-teen? Or was the female you spoke to an actual adult woman? Maybe try speaking to one of the "boys" next time.

And a gallon WITH hardener runs a bit over a hundred bucks, cheaper than WEST at most places.

Got your life yet?

But at any rate, Soller Composites sells small quantites. http://www.sollercomposites.com/composites/Epoxy.html

And for the posters that think WEST is the only "boat" resin in the universe and ADTECH isn't, I am LMAO... ADTECH was developed as a marine system. It is just a lower viscosity, harder and more heat tolerant marine system. But like I said, whatever blows your skirt up.

Tom

PS: And yes, I have used a LOT of WEST epoxy in the past. Way back then IIRC the drums we bought were 44 gallons. I think now their drums are a bit over 50 gallons... but don't quote me. It is a good resin system. The last vessel we built with it was a 44 foot cold-molded tri.

I just like ADTECH better now. Easier to work with. MUCH lower viscosity means easier and light layups. Harder. Higher Tg. Just better for modeling than WEST.

I would buy MSG L285, it is even better than ADTECH, and is even certified for man-carrying aircraft. But the HAZMAT charge on the slow hardener is a killer. Generally, the slow hardeners are the most toxic. But ADTECH slow hardener does not require HAZMAT fees... at least the last few times I have purchased any.

sensei

Here is a link to an epoxy resin manufacturer I have been using as one of my suppliers in business for the last 20 + years or so, anyway they have many application specific systems from flexible to very rigid. We primarily use the HTR 250 Clear, the HTR 212, and the HTR 6040 slow from this particular supplier. Most all of what we manufacture is done so from high temp epoxy pre-preg systems but we do use several hundred gallons of wet layup epoxy systems each year as well. http://www.resinservices.com/custom.asp?CustomID=14

Bob