Aircraft - General
Foam to Composite Scale Model Mold
Foam to Composite Scale Model Mold
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Two pilots. Pilot in command is animated with the controls.
Crammed a couple Gi Joe guys in. My shop looked like a CSI crime scene with body parts all over.
Early days using a donated T-28
Accessing what can be improved.
Nose gear bay filled in
Front canopy frame and cowl flaps filled in. New firewall installation and placement.
Rear horizontal stab setup. I filled these so they are set back and will install air valve stem for easier removing of finished parts.
Prepped and parting plane installed. Putty around edges to make a fine separation edge.
First mold half with tooling coat.
Finished cowl mold number one. I have made several changes and switched to better tooling coat for future production molds.
Left is the plug and the right the first prototype. Unfortunately I used a spray can primer that had not hardened enough so had blemished the part.
Starting from the rear and working forward. Panel over laps evident here.
Ready to create raised over lapping panels Yellow tape is the panel edge when done
Access panels are both raised and indented depending on what is required.
You can just see how the battery box will be molded in
Ready to install supports,clay then wax. Also, need to attach alignment nubs
Forward fuse section detail. The rudder looks bloody awesome as it is all curved with lots of details.
Parting planes being attached to masking tape
Thin card stock used to make PP templates
Ready to clay
ready to clay. I sand a slight bevel to the edges next to the plug that allows better leveling of the clay
Air valve stems attached with two sided tape and the back hole cut out. Adding the caps allows control of the air pressure flow.
All clayed waxed and looking pretty. Next step is a couple of very light coats of Mold release PVA. Then Bam!!!
Pre cutting some of the 3/4 oz cloth. I make small 1" squares of 3/4oz then then halve them and cut out a half circle to lay over the alignment dots. This builds them up with no voids.
First tool coat applied very thin
Second tool coat medium thin
inside the house to cure over night. Taking Sunday off to test fly a friends model.
Templates for parting planes
Back side of parting planes showing the masking tape and PP's attached with hot glue
Ready for clay after a couple of wax coats
Vertical plane created from the last layup with alignment dots molded in
Clayed up and parting coat applied
Tail end tool coat x 2
Added mid parting plane along with alignment dots.
Added plastic shims to create a leverage channel so that I can easily get inside the parting plane to separate the mold halves and also the layup once done.
Installed tire valve stems in deep pockets to help release the mold with compressed air if needed. I'm sure it will be needed.
Tinted this section (thx Rodger) and used cotton flock and tool resin to build up the large sharp angled hinge blocks that gave me a lot of grief on side one. I figured if it does not work I re-mold it again. The flock worked perfectly and made life so
Decided to pop off side one that had cured for two days and see what voids I would have..... Bloody hell! not one void and a perfect two part mold. Side two seemed anxious to want out too... So I put the air to it and out she popped. Also perfect.
To add cream on the cake, the plug survived almost perfectly with very minimal damage to a couple of places. Damage was my fault going a little deep with my plastic pry instrument.
First layup... YUCK Total failure. I trashed the mold and part.
A series of failures and successes.
Now this grey unit would have been perfect if I had only used a good cowl skin. Instead being my first test I used one of the crappy ones. Oh well, a little putty and will be usable.
Made a silicone cast of the radial engine plug. I have learned to always pressure cast any mold with any amount of detail and or depth.
Almost final production cowl which was made in three sections. First layup the cowl skin. then place the skin into the purple silicone mold. Then cast the nose lip and engine in urethane plastic with micro spheres to keep the weight down. This method
Cut up, cleaned up and waxed. This pic shows both halves joined.
Detail very good
Nice detail pickup throughout.
Variable heat curing oven
Detail came out really nice.
New cowl fit
original wing test fit
shown is a 6S 5000 EDF battery. Lots of room for double that if required.
Motor and wings installed to test fit. Wings are pinned and bolted.
Note the rolled edge for the glare shield. Once the layup is done I will trim just under the rolled edge and this will give me the edge padding protection.
Rough placement for the pic
Wanker navigating has the RIO.
Nose lip thickened and attached to cowl sides.
Fitting to fuse and re-shaping.
Rudder molds came out perfect and very easy to get the plug out. Just need cleaning and waxing up ready for the first part tomorrow.
My new way of doing the retract and steering. Works great with no binding and very easy to service.
Entire cockpit plugs getting close to making the molds.
New cowl looking much better and more scale in appearance. Still needs a lot of sanding then panel lines and rivets etc.
Retract test fit along with the cowl profile.
First rudder out of the new molds. A couple of tiny blemishes but will take care of that on the following layups.
Next set of plug ready to mold.
Cockpit tub clayed up and ready to mold.
instrument and glare shield in place
Needs a nice panel
Test fitting all elements and happy with the results.
initial use of resin, micro balloons and cotton flock in the sharper corners.
3/4oz then a layer of 6 oz. Install the foam hinge ribs.
Part is trimmed all around the edges then a thin application of resin, balloons and flock to both sides at the lip.
Close up the mold halves and tried the new spring clamps for the first time instead of nuts and bolts.
Fresh out of the molds. You can see a bit of white flashing that easily trims off. The lower rudder also shows the pre-installed control horn. The clamps and horn works great and is 4 grams lighter than the one above without the horn. The top one uses
I got lucky and was able to fit a flat sheet of plastic that when glued will pickup all the curves for the front windshields. I'm using 0.015" clear petG on the flying versions. This will save me having to heat form.
New cowl plug all ready for waxing and PVA. I'll make the new mold over the next few days.
The complete horizontal stab and elevators are ready for wax and PVA then into molding.
Cowl halves molded
One elevator side set. Rivets on top half and limited detail on bottom.
Quick assembly and test fit of all flying parts. The wing is the original off the shelf unit made in EPO foam.
Our new grey baby. Stronger, nicer and the same weight than the original MKI unit.
Details really pop in the pre-painted grey scheme.
Recessed gear door bay added. Blue tape is where the air release valves are for mold separation.
The damaged section is where the air valve release is.
3/4 oz first layer and cowl rim filler with balloons & flock 25 grams lighter than original.
New engine out of molds this morning
Mama and new babies
Cooking in heat box
Cutting cloth with rotary cutter and pad works great and very fast
Engine, engine two part mold and finished cowl with new engine.
Better view and ready to mount
Finished internal installation
Looking very good. Fuse windows and gear bay trimmed out ready for assembly.
Just need the elevators
Dry mounting of everything to date
Rudder attached with 1/16" aluminum rod. New elevators test fit. The elevators will be on a bearing pivot and invisible.
Front view of cowl and cutouts.
Test fit of rear end.
New style radial with mounting lips built in for attachment to cowl.
Glass web applied to absorb shock
Franken Arm. Took two aileron arms and converted to an elevator for hidden internal control.
Messing with my panel layouts prior to making a master mold. I had to make several different shapes and still need more but these will have to do. Retract lever should look cool.
Rear end dry mounted aligned and will install ASAP. Waiting for the arm bearings to setup.
All I need is the glass then install.
Instrument Panel of a Me-163B Komet.
The Messershmitt Me-163B Komet.
Me-163 Komet Top-View.
Me-163 Komet Internals. Thick foam walls. Air-channel through floor.
Num 3 super light and still strong
Heavy duty battery trey
Wish I had a laser cutter
New type servo mounting
HighEndTechnologies Me-163 Propellor Jet Price: US$110+post Where: http://www.extremerc.com.au
Me-163 COMET Speed 500 from K&A Models. Epoxy fiberglass fuselage and wings.
Almost ready to install
Quick install of the front and rear instrument panels.
Did this in ten minutes so not a great fit.
Chromed exhaust shields. Needs the pipes
Stab tip painted
Canopy is all beat up but still not bad for the prototype. Did not bother to add the side instruments or any detail for this test bird. Even my Gi Joe Pilots are taking a nap since going AWOL
Cowl mold using mask to paint the primer on
Two tail section sets complete with the cowls
Super bug and instrument panel molds
No four fuselage
Motor placement without a motor mount. With the angled firewall I can directly attach the motor using blind nuts.
Left wing covered with the right ready to cover
Both tops covered and ready to trim
Control surfaces covered with resin and 1oz cloth.
Painted black trim
Figuring how to cut the bad bits off
Bad bits removed and ready to insert back in to the molds
One side finished and ready for edge trimming.
Both halves together and being seam taped.
Out of the molds and looking like a fresh layup.
Spliced seams just need cleaning up then a bit of spot putty and paint
Very clean seams.
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