Bristol County Radio Control Club Forum

First I will post the small pilot I made from an already made split pilot that I bought from a company specializing in the sale of RC vacu-forming different sized parts. I am going to use some epoxy and a couple balls of foam to take some of the space of the epoxy to help keep the weight down some. Some companies have the split halves and you can make a few before the plastic halves start to get damaged. One company I buy components reasonable is right here. I like making my own material if I can also.
https://parkflyerplastics.com/cart/

Wax the inside of the mold before applying any epoxy. Mix up some epoxy and use a toothpick to wet down the inside of the both halves of the mold. I only used the bust area. I then made the 2 small foam parts to use up some of the epoxy space.

Next I fit the halves together and line them up then use paper clamps all around the perimeter. Turn it upside down and hold it that way for the duration of the curing. While it is upside down place the rest of the epoxy mix into the mold.

After it is cured and split apart use some lacquer thinner and a rag to wash off any wax that is on the pilots surface and to dull it down. This allows the waterbase paint to grab also. Paint it up and mount it where you want it after all the seam and slag is sanded away.

Remember. Click once for ZOOM 2 times for a deeper Zoom.

Using the Stock Canopy to Create a Mold:

2-9-2016 GWS Mitsubishi Zero - Making a Canopy Mold

I made a foam cradle for the kit Zero canopy. It just has to hold it level so it does not run over the edge. Nothing fancy. Next I waxed the inside of the canopy with mold release wax and set it in the cradle.

Next I grab some 60 degree water and a plastic tray to mix the Plaster of Paris together before the pour. I did not mix by weight or volume. I just dumped a small pile of powder in the tray and add the water. Stir it like heck to a consistency of loose pancake batter. Pour that batch into the upside down canopy. It filled up as far as the mix allowed and I stirred it some more with a Popsicle stick to make sure there were no bubbles. I then mixed up another smaller batch and pour that in just about to the top of the flat edge. Stir it again.

I could see it was already starting to kick as I smoothed the top of the Plaster of Paris. I felt the canopy and it generates a small amount of heat as it sets up. I left it all sit there while I ran an errand and to let it cool off. When I got back too the mold I flipped it over and a light tap it fell out and is near perfect. The POP material is not rock hard. The haze in the canopy is just wax and moisture and cleaned up fine. My next step is to smooth light flaws, fill, and then put maybe a thin epoxy mix coating on the outside to make a harder skin than the existing POP. Warm the epoxy a little and it will thin smoothly. . I will preserve the mold to make future canopies for replacement or maybe some other kits. I already have my home made VacuForm machine when needed.

If one can find molding mix called "Ultracal" it is better to work with. It allows 30 minutes working time instead of 10 minutes with POP. It gets rock hard. It is made for making molds. A good product. I think I will make another mold from the engine cowling soon. I have easily gone through over a dozen of those. The break and dent easily. After the mold is made I will make a fiberglass cowling from it on the inside for the plane. I will save this one.

Making the Cowling- Male and Female Molds:

Using the stock vacu-formed cowl I uses the inside to make another cowl and I gave it a coat of Mold release wax. Then mixed 2 part epoxy and a couple layers of 0.7lb glass cloth. Laid it up and sat overnight. Drill a pinhole up front after slipping some thin plastic flat strips all around to pre break the sticktion. Then a puff of air pressure and a nice POP and it flew out. Had some pinholes and flaws to spackle up, primered, and filled. It still needs a little sanding seen near the gun hole. But it came out very strong and only at 5grams more in weight. Worth it.

Going further the same plastic cowling is used to make a Plaster of Paris molding. So far I made 2 epoxy glass cowlings for my planes.

THE VACU-FORM BOX

Member Joe Gubler Asked:

I'd like to see a picture of the home built vacuum form machine. Do you use an AC type evacuation pump to power it?
The Vacu Form box is made with peg board, Hard board from the backs of furniture and wing nuts to sandwich the plastic stock. The intake is a PVC pipe adapter that fits the shop vac. The split open top plate has Atlas tacks hammered in around the perimeter. The points stick out slightly and the tack heads cut off. This helps hold the plastic when the top is compressed with the wing nuts.I place the to plate in the oven at about 300 degrees and when it sags I turn on my shop vac and with gloves pull it out of the oven and Woop! It sucks it down and it is ready after some trim. The canopy will be made soon. There is a Me-109 canopy and some blisters I made in the picture. The stuff has to be raised off the peg board so the suction pulls it right down to the mold edge. Nothing exotic here. Just adlib home made as it does the job. I use .020 Vivek plastic from an Amazon advertiser. 4ft.x4ft.x.020 Vivek. Cost around $20USD shipped free. Enough for 16 -1 foot pieces for many parts.

http://www.amazon.com/United-States-Pla ... astic+Corp.

Molding a New Canopy Procedure. Using my Vacu-Form Box:

Here is a question member Joe Gubler asked about a Vacu-Form Box:
I'd like to see a picture of the home built vacuum form machine. Do you use an AC type evacuation pump to power it?
The Vacu Form box is made with peg board, Hard board from the backs of furniture and wing nuts to sandwich the plastic stock. The intake is a PVC pipe adapter that fits the shop vac. The split open top plate has Atlas tacks hammered in around the perimeter. The points stick out slightly and the tack heads cut off. This helps hold the plastic when the top is compressed with the wing nuts.I place the to plate in the oven at about 300 degrees and when it sags I turn on my shop vac and with gloves pull it out of the oven and Woop! It sucks it down and it is ready after some trim. The canopy will be made when I need one. There is a Me-109 canopy and some blisters I made in the picture. The stuff has to be raised off the peg board so the suction pulls it right down to the mold edge. Nothing exotic here. Just adlib home made as it does the job. Let me show you how I start the process.

I cut the .020 Vivek plastic sheet into 1 foot squares. The box was made to take 1 foot squares.