K & B Resin ??

O.K. Gang: I came back to modeling after about 5 years and no K & B resin any more. So what are you guys using now. I have the Concepts 1/4 Fleet Biplane. The cowel is made up from balsa blocks. I used to just coat with the resin sand and paint. What a good alternative ??

Denis Winters <

Reply to
Denis Winters
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EPOXY RESIN

Reply to
Courseyauto

And who makes the "Epoxy Resin" Not sure I have seen this ??

or maybee I wasn't lookin ??

Denis

Reply to
Denis Winters

And who makes the "Epoxy Resin" Not sure I have seen this ??

or maybee I wasn't lookin ??

Denis

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---------------- There is a resin available,usually in larger quanities. I usually just thin epoxy glue (SIG brand ) with acetone,it will also slow down the drying time. DOUG

Reply to
Courseyauto

There aren't any items that replace the old K&B Polyester Finishing Resin. At least I haven't found one. OTOH, there is a good item that works well -- not like K&B -- and doesn't smell nearly as bad as K&B. That is ZAP epoxy FINISHING resin. It is more brittle and doesn't have the sanding qualities but a couple coats will seal things up, especially over glass. Primer is still required. Sanding can be enhanced with addition of some micro-balloons, however some thinner may be required. Alcohol or epoxy thinner from the hardware/home stores will work.

Reply to
CainHD

Get thee to a boat store. It's called polyester, or fiberglass, resin. Very common. However, since it's also fairly toxic, learning to use something else is not a bad thing.

Reply to
C G

Reply to
Mike Gordon

Contrary to what another poster said, epoxy resin is far LESS brittle than polyester (K&B, etc.) resin. That is why most people switched to epoxy many years ago. Not only that, most of the better fiberglass fuselages, cowls, etc. use epoxy resin for the same reason. Epoxy remains somewhat flexible while polyester resin gets more and more brittle with age.

If you still want polyester resin, any boat store like Boat U.S., Westmarine, etc. will have it. They will also have epoxy resin.

Reply to
jeboba

Last time I looked (it's been a while) Sig sold a polyester finishing resin that was equal to, if not the same as, the old K&B stuff. Try their web site:

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You can also go to most marine hardware stores and buy "finishing" or "surfacing" resin, which is also the same polyester stuff. Beware that their are several flavors of resin in a marine store. There is a "bonding" resin which is designed to adhere the cloth to the surface being glassed. It does not ever get beyond the tacky stage of cure. Then there is a "covering" resin designed to go over the bonding stuff and make a hard cure. Then there is the "finishing" stuff designed to be easy(ier) to sand. TAP plasics also sell a polyester resin, although I don't believe it is of the "finishing" flavor. The finishing resin has more wax in it to aid in the sanding properties.

Reply to
Tom Minger

The information above could use a bit of amplification:

For polyester resin (the stuff you'll find at the auto-body shop, for maybe$20/gallon, or at Boat/US, etc., and whose 'hardening agent' might be 1 oz to the gallon of resin):

  • The resin is constantly "hardening", so a 10-year-old bucket of resin is likely to be just a plastic rock. The "hardener" is really a *catalyst* (typically Methyl-Ethyl-Ketone (MEK) Peroxide), which encourages the reaction to go faster. You adjust the amount of catalyst depending on the temperature at which you're working, since warmth is ALSO a catalyst for the reaction.
  • Bonding resin is "air inhibited": it reaches a soft cure, but remains tacky as long as it's in contact with air. (So when you put on a new layer of fiberglass, the lower layer turns hard, rather than remaining a gelatinous goo -- wouldn't be very strong, would it?).
  • Finishing resin has some kind of 'wax' in it, which floats to the surface and keeps air from getting to the resin during cure, which allows it to harden up properly.
  • The wax, as far as I know, is of no use in sanding. Indeed, it tends to get mixed up with the sanding process and leave your surface waxy, which is hard to paint; you need to use a special de-waxing agent to get the surface ready to paint well.
Reply to
John F. Hughes

Methinks this person NEVER used K&B Finishing resin. It ain't jest all the same!! I used several resins finishing CL speed models, and RC models. IMO there never WAS or has there BEEN anything to compare to the old K&B FINISHING resin or the K&B Super Poxy paints (Not the later line) especially when factoring in "User Friendly". I have not yet used the newer Klass Kote line but I will as soon as I need a good finish better than polyurethane. BTW Sig is good, but the old K&B it ain't.

HC

Reply to
CainHD
  • The hardening process often generates something called an "amide blush" (a Google search on that term will give you more info than you could ever want), which should be removed with a mild detergent solution or it'll screw up paint adhesion for all but the most aggressive paints. Some epoxy manufacturers claim to have no-blush epoxies; some epoxy users dispute those claims. (Surprise!)

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------------------- I recomended Sig 30 minute epoxy because it doesn't have this problem and is easy to sand and doesn't clog up the sandpaper. When i was building RC racing Hydro's that were made of plywood and foam,i would use a mixture of the Sig epoxy glue and acetone to thin it like water so it wood soak into the wood. It sanded very easy,i then sprayed a primer coat on and it was readt to paint. DOUG

Reply to
Courseyauto

Thanks for all the replies and help: I'm gonna go with the Epoxy Resin and work with that :

Thanks Gang

Denis Winters <

Reply to
Denis Winters

"finishing"

Reply to
jeboba

Welllll, I have been painting airplanes since about 1955. I used a LOT of K&B resin and paint. My only complaint was always that it was too brittle. I switched my finishes to "Imron" and other polyurethane based two part auto paints because it didn't 'chip' so bad as K&B. I switched all of my resin use to epoxy for the same reason. I built formula 1 pylon racers by the boatload for people back in the 70's and 70's. Since I had a lot of K&B on hand, I offered the airplanes finished either with K&B or Imron. NOBODY opted for the K&B. The secrets are in the preparation and application. You DO HAVE TO KNOW what you're doing to get as good a finish with the polyurethane. The K&B paints were so thin you could pretty much shoot em right out of the can. The poly's require reducing and you'd better get it right. More amatuer painters probably found K&B easier. I didn't. I have now switched to giant scale warbirds and use acrylic (latex house paint) exclusively. If you're not looking for super shiny, it's the best yet. You DO have to use High Volume Low Pressure spray equipment to get a really good finish with it so it's probably not the best for less experienced painters.

The main thing is, use what works best for you. I haven't looked at the Klass Kote either because I am really enjoying the HUGE cost advantage of latex!

Reply to
jeboba

On 10/2/2004 4:53 PM Ted shuffled out of his cave and grunted these great (and sometimes not so great) words of knowledge:

Why not look into 1/2 oz glass cloth applied with water base polyurethane ? Strong, lightweight finish that is easy to sand and takes a finish quite well AND THERE ARE NO FUMES.

Reply to
Ted Campanelli

Horrace,

There are many paints that are better than just about anything model-specific. Modern automotive finishes are far more flexible than the average hobby product. you can add the flex additives to many of them and they will not break on the new plastic bumpers.

I have used auto base coat/clear coat systems on several planes. Not only is it lighter, but also nearly indestructible and fuel PROOF to at least 60% nitro (the highest I ever used).

Regarding resins, I have always used Z-Poxy finishing resin. It is flexible, easy to sand and holds primers very well. May epoxy resins have a hard time accepting primers unless the surface is thoroughly sanded first.

Reply to
Paul McIntosh

SIG polyester resin is as close as you will find and works well and should be available at you LHS.

A good altenative is Tap Plastics Super-Hard Epoxy Resin. Used to go by the name "4 to 1 Epoxy." It has a very hard cure and sands very nicely.

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Great for doing what you have in mind. Also for 'lost mold' cowls from foam.

Reply to
Doug Dorton

I have been using the water based poly with glass with great success also.

Reply to
jeboba

Reply to
Brad

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