b&b epoxy vs. MAS epoxy

[sscoville]

I have some experience with MAS epoxy.  I understand that Graham sells epoxy that uses a 2:1 ratio - the same as MAS.  I've only used the Fast hardener with MAS.  Anyone have any information regarding how these two products compare to one another? 

[cdunc]

I have not used any other epoxy other than Graham's, but then I have not even finished a single boat.

I am using the slow hardener.  All my building has been in the colder months of the year so the slow is really slow, almost too slow.  But it does give you plenty of time to work.  I am hoping with the weather warming up things will move along a little faster.

Craig

[PAR]

Both are extremely close to each other in physical properties when cured. Unless you're doing some fairly high tech laminating (at which point you'd be using a different type of epoxy) then either will work just fine. In fact you should be able to swap out resins are hardeners (mix and match) and still get a good cured result. I wouldn't recommend this, unless you understand the way epoxy formulators modify their products.

[Oyster]

When I didn't know any better I purchased West System, Mas, and Evercoat epoxy resins. I then used Raka which was one of the first no fancy advertising outfits and also had great results with their resins. I still use the big names when someone buys it for me. You can make almost any epoxy work even the thicker ones by altering the viscosity by microwaving it or placing it in a sunny area of on a heated sruface such as a warming tray or in a cooler with a lightbulb in it. But for the last three years, IIRC, I have purchased resin exclusively from Graham even while using Fiberglass Coatings five to one hardeners for the quicky jobs because it kicks fast in a bulk situation.

So far, I cannot find a problem, only that it does crystalize in the jugs in cold times which is consistant with most other resins that sit for a while. Thats easy to cure by also sitting in a direct sunlight or warming it in a big pan of water or in the microwave if you wife is not at home. I even use this technique for assisting the cure of the slow blend by warming just the resin before mixing the hardener into the resin. His prices are more than fair and service is supreme if you grab hold of his ear and don't let go until he writes the order down. ;D

[sscoville]

I have been wanting to try using one of those paint mixers - the auger type you use with an electric drill gun/screwdriver.  I was thinking the process would go like this: 1. pour resin and hardner into container; 2. insert auger and pull the trigger until it's mixed well; 3. finish mixing by scraping sides and bottom of container with tongue depressor (if auger is not effecient at getting to the sides and bottom of container) 4. Add thickner, if desired, and mix some more.  5.  Put dirty auger in bucket of white vinegar to soak; 6. Wipe any left over goo off of auger and rinse it in a bucket of water; 7. repeat from step one

Anyone see any problems with this procedure?  Is the rinsing with water necessary after using vinegar? 

[tom151]

Anyone see any problems with this procedure?

First, the key to preparing epoxy is to insure the resin is scraped away from the sides and bottom of the container. By the time you've done that - the resin is nearly fully mixed.

Second, the less mixing the better - because (a)getting air entrapped only causes blemishes or voids that need attention later, and ( the friction of mixing itself adds heat and reduces pot life.

Last, adding any type of extender requires further mixing thus reducing pot life, so you can be more brief with the initial mixing.

Skip the auger/drill -- a disadvantage overall -- my opinion only of course!

[BryanLee]

I do use a mixer, it is small, a piece of wood about 4 inches long and 1/2 inch by 1/2 inch square. I put 2 finishing nails in each side at staggered heights and a screw in one end then cut the end off the screw. I use the screw to chuck it into a small drill press at low speed. It works well, I have never had a problem with air bubbles in the epoxy (I use MAS slow cure, if that might make a difference) I do notice it gets a little cloudy from air mixed in, but it clears up fast and I have not noticed any ill effects in the finish of the epoxy.

I only use the mixer to mix the epoxy before adding any thickeners, and use scrap wood or plastic knife for mixing in the thickeners. I never clean it, just put some newspaper under it to catch the drips. The extra epoxy creates little stalactites of epoxy off the nails which are handy for scraping the sides of the cup while mixing. At first I had to be careful not to cut the cup with the nail heads, but now that they are well covered that is not an issue.

I use plastic Dixie type cups for mixing, 16 oz size which I never fill more then half way, but I did learn this week to make sure they are ROUND all the way down! I got some with little impressions in the side, which I guess are supposed to help you hold the cups? Or just to look cool, but when the mixer hits the bumps, it tries to knock the cup from my hand!

Not sure this is the best way, but its what I do, for what its worth.

Bryan

[Greg Luckett]

I have never needed a mixer, just using the tongue depressor or an acid brush, and never mix more than about 6 ozs at a time, if that is what 5 squirts of the West Systems pump equals.  I use the fast hardner because it is usually cold here, but did shift to the slow hardner during the heat of the summer for about 2 weeks.  Once I have used up my stock of West Systems I plan to order a shipment of Graham's stuff.  I must admit I am a bit concerned about his fast hardner not being as fast as the others, but then that might allow me to mix slightly bigger batches too.  If it works for Ray, it should work for me too.