fw190

My Feedback: (37)

I use resin 105 and 206 hardener. I am fabricating a fiberglass fuselage. The 206 is a bit too fast (specially on hot days) and the 209 is way too slow (even on hot days, but gives me plenty of time taking excess resin out).

So my plan is to use the 206 as the first coat to my mold and wait till its tacky (about 2 hours) and proceed to use the 209 harderner when laying down the glass cloth. Is there a problem doing this??? Any thoughts and ideas...

I just don't want to start with a 209 harderner or the layup process wil take 2 days instead of one day...

Thanks,

fw190

Flyingmike-inactive

I have found that when using epoxy on my carbon spinners, check out my gallery. they take 24hrs to cure on 205/105 and its cold in my workshop ~10 degrees C but I always leave it for a couple of days pop it out and then let is stand for a few days before polishing, as it is flexable and can distort when taking is out of the mold, If the environment is hot then it will be even more flexible, I would suggest using the slower setting resin to give a stronger job and then give it time to cure. after all whats an extra day!!!! What fuselage are you moulding?

Mike

Jimbonk

Here's the only trick I know for slowing down a 105/206 mix. After mixing , Spread it out on a flat surface. As epoxy cures it gives off heat, spreading out the mix lets this heat dissapate quickly. When you need more resin you just scrape it back up.

Jim B

fw190

My Feedback: (37)

I am also including response from WestSystems Tech Support... please read....

"Hello Vic,

Your part can be laminated with both 206 and 209 hardeners. It is very critical that each hardener is mixed at the correct ratio, 206 at 5:1 and 209 at 3:1. As long as the hardeners are mixed in the correct ratios there will not be any problems.

If you have any questions or need more information feel free to call or write.



Jeff Wright
Technical Services

Gougeon Brothers, Inc. "


Flyingmike.... here is the mold not yet complete but half at least ...

Vic

SCALECRAFT

My Feedback: (13)

Hi Vic

Your P-38 looks good.

As you may have figured, the west systems are most versatile.

The only thing I would beware of is the fast hardner is thick. In cold weather it will be even thicker, same goes for the slow.

So, when you layup your model consider the difficulty of pooling on the "skin" 1st layer and the removal of excess resin from the glass layers.

I remember your layups, I don't think it will be a big problem for you.

Good luck

steve

Flyingmike-inactive

Hi

That is fantastic, I know nothing, are you a moulding god!!!!!!!!!

Mike

persius

The pattern work (proper term for the part used to make a mold's shape) is very good and you have the basics for making a mold. I have noticed some areas you should be concerned with. The vents on the engine cowl will cause a problem called "back-draft" and will trap the pattern in the mold. I would recommend you remove them and make a separate mold for them, or make a "loose-piece" in your mold. The cooling nacelles look like you may have split them below their maximum profile, again resulting in back-draft. The parting surface appears to be a bit too narrow, especially if you intend to vacuum the skins in the mold. You may also want to use a gel-coat for your first coat of resin in the mold. This allows for a very smooth and repairable surface to mold against. Epoxy gel-coats are available and I believe Gugeon has an additive to thicken the West resin into a gel-coat. When laminating the mold, you can put all laminates on at once and even use a vacuum bag to draw the laminates down. You also need to put a series of cross braces on the back of the mold before it is removed from the pattern to maintain its shape.

If you have some other pictures handy I would be glad look then over and offer any other help, I have made patterns, molds and composite modes professionally for over thirty years

fw190

My Feedback: (37)

see next post

fw190

My Feedback: (37)

Flyingmike - Mold making is not difficult it is just a process to be learned, of course we all have our own ideas but its generally the same. Only been molding for about 3 years, I just like to dab on epoxy... . Making the plug is the difficult task....

Persius, Good eye for details thanks for the input. I did spent a year making the plug and thinking about how the molds will be made, also had ideas how the parts will be layed-up and making
this process a lot easier. The mold is done! the plug was removed in about 1 hour without damage to the plug, but it took me 4 hours to cut the flange.

Steve, Thanks!! I just put the question about the 206 and 209 to figure out how to layup a single piece fuse, center wing, and booms without adding too much weight. I have noticed that the 206 working time is short when laying down multiple layers. I need the time of the 209 to add all the wooden pieces (puzzle) before the halves are put together. I jdid not want to use a 209 hardener solely because of the first layer will take several hours ( 4-8 hrs!) to get tacky. I don't know how long the entire layup process will take but hoping to fit it to an 8 hr session.

Thanks all!!!

Vic

I finished the main mold you guys can take a look at..

www.vicrc.com