Foam to Composite Scale Model Mold - Page 9 - RC Groups
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Dec 12, 2012, 10:16 PM
EB-66C Team Member
J Morgan's Avatar

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Dec 16, 2012, 02:45 PM
Registered User
acesimmer's Avatar
Got the cockpit tub and parts molds made and already pulled a couple of tubs for test fitting. Fits great, but I need to beef the tub up a little. I will also try vacuforming the parts as I still have the plugs in good condition.

Next step is to finish up the instrument panel facia and side panels then the cowl plug and rear stab section. Should have all that completed this week and molds made.

Once the above is completed then I'll make all new parts and build a flying plane. For the first plane I'll use the original wings with retracts, flaps etc already setup to just bolt on. I will then do a series of test flights and check for upgrades if any then make the new wing molds and then done.

This fuse is getting to beat up after hacking and fitting test parts and dropping it several times.
Dec 18, 2012, 02:27 AM
Flying Low
cbarnes0061's Avatar
looks cool
Dec 20, 2012, 11:57 AM
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DamonH's Avatar
Outstanding work Ace!
Dec 20, 2012, 07:01 PM
No Hangar Queens!
Willsonman's Avatar
That is some great stuff!
Jan 02, 2013, 05:54 PM
Registered User
acesimmer's Avatar
Holidays are over and now back on the build. Cleaned up the fuse molds to lay up fuse 2 which is the flying version. I have all the retract formers made up and re-enforced with glass cloth. Just have to glue into the flying version. Cockpit is done except for molding the instrument panels for front and rear. I have everything figured out for wings mounts etc. The next fuse will be lighter and stronger in certain areas. I also have the rudder single rod hinge installed. I need to make up a template/jig guide for drilling through both the stab and rudder hinge points in one go.

Fuse 2 will be pre-primed in the mold so that I have a better chance of catching flaws that may need to be fixed prior to laying up a bunch of parts. The plan is to fly the prototype in early Feb using the original foam wing set as they have gear and controls already installed and will save time. Once I get a few flights in then the wings should take about three weeks to mold and layup a part. Then into the bright blue sky once again.
Jan 03, 2013, 04:55 PM
EB-66C Team Member
J Morgan's Avatar
Good to see you back on it Ace!

Jan 03, 2013, 05:10 PM
Registered User
acesimmer's Avatar
Thanks John.... Next week I'll be making four molds plus the flying fuse. Got all the parting planes made today so tomorrow will set them to the plugs and a couple of coats of wax. The weather is so cold right now that I cannot spray outside. So having to do it in the shop which means I leave it closed up for a few hours while the parts gas off. Causing all kinds of delays.
Jan 09, 2013, 09:02 PM
Registered User
acesimmer's Avatar
This week I'm moving along nicely. I have several molds in the build process. Two in the pics completed and several to be finished tomorrow. In this set I'm using a different PVA and am not very pleased with it. I think that I may have gotten old stock as it is very thick and unsprayable. Seeing it said to spray as is I did the molds in the pics with it just to see. Final result is nice molds with good release but a dull surface. So I will have to buff up the molds a little. The molds in build uses the same PVA but I diluted it a little and now it wets out much better.

I decided not to apply full detail to the bottom of the model as it really serves no purpose for a stand off scale model. However, the upper surfaces are fully detailed and are coming out very nice. This little bugger is really looking sweet.

I need to layup the cowl ASAP so that I can finish up the engine plug and make the mold. The modified more scale like cowl rim will be so much easier to layup now with the larger radius lip. The first version was a disaster being to sharp and also none scale in appearance. Note... In the cowl mold pic you can see how I insert a tire valve stem to help in releasing the parts in deeper cavities. So far this method works great.
Jan 09, 2013, 09:34 PM
Life begins at transition
PVA can be thinned nicely with ethanol. Mine is 30-60% by weight according to the label! The guy just mixed it at the shop until it looked right I think

Coming along nicely, you move quickly
Jan 10, 2013, 05:09 PM
EB-66C Team Member
J Morgan's Avatar
Looking real good Ace

Jan 11, 2013, 08:47 PM
Registered User
LuvEvolution7's Avatar
this is amazing. love the Trojan. I'd be down for a fuselage if you sell them.

Jan 13, 2013, 12:41 PM
Registered User
acesimmer's Avatar


Myself and my buddy got together today has we expected the birth of Fuselage MKII. I joined the halves at 10am then into the heat box for a 100 deg bake for 4 hrs and out she pops looking lovely.

We assembled the white fuse with all the different prototype parts made to date. We then placed it on the scale and loaded up everything that is required for a completed flying model. Weight so far with 5S 4000 battery, gear ESC, servos etc is 7 lb 2 oz. I figure the ready to fly weight with these bigger batteries will hit 8 lb. I'm going to maiden using the larger battery pack, ESC and larger 600 KV motor.

Once flying we will then begin loading up the airframe to find best max flying weight that will provide us the data needed to design and build the composite wing. I can easily lose 1 1/2 lbs off current setup by replacing the Battery, ESC and motor along with lighter wheels and oleos.

I have flown this exact same model in EPO foam at 8 1/2 lbs which is perfectly acceptable and flies rock solid. All the flight test will be performed at 4200 ft ASL. At lower altitudes the model will perform event better.

The new fuselage is the same weight as the white one but is stronger in strategic places and balances out much better. The finish is far superior now that I have the new technique for laying parts up. After painting the mold I use the resin, balloons and flock mix in the sharp corners. Then 3/4 oz cloth on all sharp outer and inner edges and detail areas. then the whole skin is 2 oz cloth. This is followed by 6 oz cloth over everything. Certain areas like the wing saddle and engine, gear mounts are given more layers. The 6 oz cloth is now applied with one wide strip running the entire fuse length. Then 90 deg bands of approx 6" width layed up with 1/2" overlaps between that provide rigidity in both plains. So the end result is 6x6" 6 oz panels surrounded with 12 oz ribs not including the 2 oz on every surface. It seems to work really well and I'm very happy with the results.

I also have all of the the molds made and currently being waxed and prepped. This week I will make all of the new cowls, control surfaces and stabs that have all the scale detail. Stay tuned.......
Jan 13, 2013, 03:34 PM
chrislarkins's Avatar
keep up the good work!

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