Epoxy: any problems with RAKA?

SpeedCom

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Sep 15, 1997, 3:00:00 AM9/15/97

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>I had exactly the same problem with MAS while building 2 CLC kayaks.

A neighbor and i are beginning construction of 3 boats using plywood and
epoxy. We have chosen RAKA due to price. I guess it would be prudent to
inquire whether anyone had any serious problems with this brand. All
comments welcomed.

Cheers/Don

Donald Carron, Daylight Boatworks
clan MacDonell of Glengarry

Spee...@aol.com

"The mind has lost its sharp edge. We hardly understand the ancients any more."

Bill Derby

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Sep 15, 1997, 3:00:00 AM9/15/97

to SpeedCom

I am finishing my 1st and 1/5th boat (other 4/5ths done by some else) and I would
not go anyhwere but Raka - Larry is a great guy, and they will work with you at the
most uncivilized hours for most businesses!

Bill Derby

Einsteen

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Sep 16, 1997, 3:00:00 AM9/16/97

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Used Raka epoxy last winter and spring with their fast hardener. I worked
in temperatures down to the upper 30's (not by choice-the temp. dropped on
me a couple of times when I thought I was safe), and never had a problem.
The owner was very helpfull, the service was prompt, and the prices were
great. Couldn't reccomend them more.

George R. Burns

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Sep 16, 1997, 3:00:00 AM9/16/97

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SpeedCom wrote:
>
> >I had exactly the same problem with MAS while building 2 CLC kayaks.
>
> A neighbor and i are beginning construction of 3 boats using plywood and
> epoxy. We have chosen RAKA due to price. I guess it would be prudent to
> inquire whether anyone had any serious problems with this brand. All
> comments welcomed.
>
> Cheers/Don
>
> Donald Carron, Daylight Boatworks
> clan MacDonell of Glengarry
>
> Spee...@aol.com
>
> "The mind has lost its sharp edge. We hardly understand the ancients any more."
>

Don,

I recently finished a strip-planked kayak constructed mostly with System
3 epoxies. I used their basic resin/hardener, and their Clearcoat
resin/hardener. I also tried some RAKA, and WEST epoxy toward the end of
the project, for the hatches, hatch combings, and seat bucket.

I consistently experienced problems with the RAKA epoxy cratering,
(fisheyeing). This only happened when it was applied over a previously
sanded coat of epoxy. This problem evidently is not a simple one to
solve, (or explain), as it has to do with static charge; and the
wetting-out, and self leveling properties of the resin/hardener
combination. I was carefull to remove amine blush prior to sanding, as
RAKA blushes more than S3 or WEST, (S3 Clearcoat is non-blushing).

I did not experience cratering with either S3 or WEST epoxies. These
epoxies are both quite a bit thicker than RAKA, and self-level a lot
better. S3 will level almost up to the time it hardens!

RAKA personnel said they had not had any complaints about cratering;
but, in the same breath mentioned that they were starting to experiment
with additives to improve self-leveling and wetting-out properties.

I will be starting another kayak this winter, and will be using System 3
for the boat. If you live in the Northwest, I have about 2/3 gallon of
RAKA left over you can have below cost. Seriously.

By the way, RAKA recently raised their prices, and if you have to have
it shipped any distance, you'll pay for that. S3 ships for free, I
believe, if you order $100 or more. RAKA is no longer the inexpensive
alternative, unless you happen to live in Florida.

Good Luck,
George Burns
Tacoma, WA

KernHend

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Sep 18, 1997, 3:00:00 AM9/18/97

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grb...@sprynet.com (George R. Burns) wrote:

<snip>

>>RAKA personnel said they had not had any complaints about cratering;
but, in the same breath mentioned that they were starting to experiment
with additives to improve self-leveling and wetting-out properties.<<

Cratering is a result of an epoxy resin's inability to adequately wet out
a substrate. It can be caused by surface contamination (oil, silicone,
etc.), electrostatically (sanding dust) or chemically (air borne chemical
contaminates reacting with free amines on the epoxy substrate). In any
case it happens because the surface energy of the substrate is lower than
the surface tension of the epoxy resin system. The epoxy simply can not
wet out the substrate in the area cratering occurs. The surface tension of
the epoxy "pulls" epoxy away from the substrate in low surface energy areas
and round craters appear. Water on a freshly waxed automobile is
instructive in understanding this phenomena.

>>I did not experience cratering with either S3 [System Three] or WEST
[West System]epoxies.<<

Both System Three Resins and Gougeon Brothers are epoxy formulators as
opposed to MAS and RAKA which simply buy from the big companies and
repackage the product. Formulators recognize the cratering problem and add
wetting agents to help prevent the problem. The addition of these wetting
agents does not make these products absolutely perfect but aids greatly in
reducing the cratering problem. The only way to really effectively solve
the cratering problem is through the addition of wetting agents. These
wetting agents are quite expensive compared to the per pound cost of the
epoxy resin. More importantly they often require expensive high shear
equipment to mix them into the resin. Thus, formulated epoxies containing
wetting agents cost more to produce than drummed off unformulated products.
Higher costs generally translate to higher selling prices. Some say
System Three and West System epoxies are worth more than the un-formulated
products because they are easier to use and cause fewer problems. Others
disagree. You get what you are willing to pay for.

>>By the way, RAKA recently raised their prices, and if you have to have

it shipped any distance, you'll pay for that. S3 [System Three] ships for
free if you order $100 or more. RAKA is no longer the inexpensive

alternative, unless you happen to live in Florida.<<

Figure another buck or two a gallon for the cost of the mixing equipment
and wetting agent if RAKA decides to become a formulator in order to help
reduce any cratering problems. Figure another couple of bucks for the
extra overhead beyond the direct costs involved with formulating. Pretty
soon the company (RAKA) that some said a year ago was the only honest game
in town competing against the giant price gougers (System Three and
Gougeon) is going to be right up with them selling at about the same
prices. Seems to me that when this happens RAKA will have forgotten "who
brung 'um to the dance". What then?

We at System Three know exactly what RAKA is repackaging. If there indeed
is a market for a cheap, no frills epoxy we could simply repackage the same
product RAKA is buying and sell it for what RAKA initially sold it for when
they first appeared a couple of years and several price increases ago.
But, since you get what you pay for; the buyer would pay the freight,
there would be little or no technical support, the product would crater
more than others and probably blush badly and the only guarantee would be
that if you mixed the resin and hardener in the right portions they would
react. In short, you as the buyer would be entirely on your own. But when
the epoxy misbehaved you could rationalize all the extra work you’d have to
do against the few bucks saved on the epoxy.

So, if you initially switched to (or started with) RAKA because epoxy
price was your primary consideration send me an e-mail with your name and
mailing address. If there is enough demand we’ll repackage what RAKA now
sells and you can have it for what RAKA charged when they first came out
with it - several price increases ago, as I mentioned above.

W. Kern Hendricks
System Three Resins, Inc.
Seattle, WA 98107
Technical Support: 206/782-7976
Orders/Literature Only: 800/333-5514
FAX: 206/782-4426
e-mail: sup...@systemthree.com
web site: http://www.systemthree.com

paul oman

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Sep 18, 1997, 3:00:00 AM9/18/97

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>-----------------------------------
As a company representing and working closely with another 'premium' grade
epoxy formulator, I agree with everything Kern says above. I also want to
thank him for the valuable educational service he provides everyone in this
newsgroup.

Just today I updated our marine epoxy web site and wrote a press release about
our very low cost epoxies (due to market demand) that we call sell for 66% of
the price of our regular marine expoxy. Despite the fact it is much cheaper,
we are only reluctantly mentioning it and would certainly not recommend it to
anyone in this group. As Kern says, you pretty much get what you pay for,
Characteristics such as no blushing, low exotherm, forgiving mix ratios,
application underwater, etc are examples of formulated 'extra' that all cost
money but result in a superior epoxy.

paul oman
progressive products
281-997-9872
http://www.netcom.com/~p.oman/ppi_tft.html

surffish

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Sep 22, 1997, 3:00:00 AM9/22/97

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I built a 16' Caravelle sail boat with it last winter in my barely heated
garage. His epoxy hold likes cement. Since then I snapped 2 masts on the
Chesapeake Bay with not damage to the mast box. Box is made of 1/2 ply
coated and wrapped with Rakka epoxy. The owner is also very helpful.