Epoxy recommendations!

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dwalker

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I very much would like to use MGS epoxy which I am familiar with, however the COVID has disrupted the supply chain and there is none to be had. Does anyone have any recommendations and positive experiences as to an alternative epoxy to MGS that is actually available?
 
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Jeffco 1307 resin with 3176 hardener is my go-to system, and I use it just like MGS 285. The numbers are comparable. I don't know for sure, but I think you can even blend the slow and medium hardeners to customize the pot and working times, just like MGS.

 

dwalker

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Jeffco 1307 resin with 3176 hardener is my go-to system, and I use it just like MGS 285. The numbers are comparable. I don't know for sure, but I think you can even blend the slow and medium hardeners to customize the pot and working times, just like MGS.

I am about to make a Spruce order and drive down to Atlanta and pick it up, so I will add a starter kit to it to try. Do you know if it is as "thin" as the MGS?
 

Marc Zeitlin

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I very much would like to use MGS epoxy which I am familiar with, however the COVID has disrupted the supply chain and there is none to be had. Does anyone have any recommendations and positive experiences as to an alternative epoxy to MGS that is actually available?
I like Pro-Set:


Used it on many planes. Plus, it's approved by RAF, which the Jeffco isn't. Doesn't mean it won't work fine - if Bob uses it, I'm sure it's also good, but I like to go with what's known to work on the type of plane you're building. If MGS isn't available, then Pro-Set is the backup. Unless you're doing strakes/fuel tanks, in which case EZ-Poxy 10/87 is the right answer.
 

Bille Floyd

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I very much would like to use MGS epoxy which I am familiar with, however the COVID has disrupted the supply chain and there is none to be had.
...
Dang -- and Aircraft Spruce is out of Aeropoxy laminating epoxy, also ! :(
I use it because there is no MDA, in it (a known liver toxin and carcinogen)
and it also is Rutan , and RAF approved.
I believe MGS , has no MDA in it , also ?

I can't even be in a room ; with an open can of West system slow hardener ;
that's what happens, when a guy misuses it for too long, (gets an allergy to it).

Bille
 

Tom Busey

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Aug 28, 2019
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A related question- with either MGS (which I've used and like), or Pro-Set, do both have to be heat-cured to 50°c for 15 hours? And is this for both finishing coats (e.g. wings) and structural bonds (e.g. fuselage bulkheads)?
 

foolonthehill

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We had some lab tests done about 3 years ago, with Pro-Set, MGS (Hexion in the US everywhere but Spruce), R&D Resin (Premium Resin tech), and one other epoxy resin, might have been PTM&W, don't recall. What I do recall is you could throw a blanket over all of them. In laminate testing of test samples, there wasn't enough difference to matter. They all handle a little differently, so it becomes a matter of which one you are the most comfortable using. We like R&D Resin because the customer support is second to none.
 

dwalker

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We had some lab tests done about 3 years ago, with Pro-Set, MGS (Hexion in the US everywhere but Spruce), R&D Resin (Premium Resin tech), and one other epoxy resin, might have been PTM&W, don't recall. What I do recall is you could throw a blanket over all of them. In laminate testing of test samples, there wasn't enough difference to matter. They all handle a little differently, so it becomes a matter of which one you are the most comfortable using. We like R&D Resin because the customer support is second to none.
The strength is for the most part comparable, however viscosity is not. Also MGS 285 is a tiny bit "thicker" than MGS 335 so is easier to use, and you can mix slow fast hardeners. The difference between 285 and 335 is 285 has a higher strength is postcured..

Interestingly enough, The epoxy system was originally branded as Shell and I used a LOT of it making aero parts for racecars. Shell then renamed the epoxy business to Resolution Performance Products, which is Hexion.
 

foolonthehill

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Yes, I was referring to the systems we are using for infusion. There are very many variables one can choose when determining pot life. From what I've been told, and I'm just a simple process guy, not a chemical engineer, is that Hexion's base epoxy, 828, is used by many of the epoxy company's as their base material, and they put whatever additives they desire into that to achieve the results they want. When we infuse, we actually use a Huntsman material. It has a long pot life, and has to set at room temp for 24 hours before demolding and post curing. But it is incredibly strong even without post curing, and flows better than anything else we've seen.
 
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User27

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We use L285 / H286 or 7 at work as it is specified by the manufacturers we work with (Diamond and others). Grob (and Extra) specify L20/EK960 but it isn't so good to work with. All need to be post cured for all structural components. 285 and L20 will take an 80C post-cure, so mfrs specify only 60C, depends on their design assumptions. Often they require something like 8 hours at 60C followed by 16 hours at 80C.
 

opcod

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Of course, it is uber pointless to speak about resin strenght and comparatif.. if it's not associated with postcure. The sole nature of the molecule need to be understand as.. post-cure is needed in the process. Ptmw is a good one for infusion and mgs 285 too. but 285 for large part you need way more tubing as you can't cover more than a feet with each inlet.
 
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