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Details: Created on Friday, 22 June 2007 09:00; Last Updated on Saturday, 19 January 2008 08:37; Written by David Engleson

Carving a Pilot Figure from Pink Foam

By David Engleson of the Minnesota Radio Control Soaring Society

I carved a pilot figure for my 60” Leading Edge Gliders Spitfire and thought some of you might be interested in the process I followed. If you haven’t tried carving a pilot figure before, you will be surprised at how quickly they take shape. With a little practice you can crank one out. There are many different ways to carve pilot figures and there are many different materials you can use as well. I use this method with pink foam because I have lots of foam sitting around and it is easy to do. Here we go.

First I looked through a few of my books on the Battle of Britain and another on the RAF of World War II. Also looked through a number of images on-line including many flying helmets and goggles for sale on different web pages. I also found some good information from my The Battle of Britain DVD. Look around and see what you can find for your particular subject.

Next I made a few sketches of the figure to better define its shape and proportion and understand some of the finer details that were found in various pictures. I have found that the more you know about the subject the easier it is to draw and carve.

I then scanned the sketches into a graphic program and fussed around to get scale to fit the LEG Spitfire. A copier works just fine too. I found that the fuse of the Spitfire is roughly 1/9 scale. I then printed out the sketches at what appeared to be the correct scale. Make an extra copy if you can.

Next I affixed the sketches onto a block of pink foam using 3M-77 being careful to align them with each other.

I then used my band saw to cut out the rough figure. First cutting the front view, taping it back in place, and then carefully cutting the side profile. You will end up with a crude foam block figure and you are ready to start carving. BTW - Don’t let this step intimidate you. It’s only foam and if you mess up, just mount another set of images on another block of foam and get after it again. Foam is cheap and you haven’t invested any time yet. Watch your fingers.

The next step is to trial fit the figure in the model. It took a little trimming to fit him in and look good.

Next I used a felt tip pen to mark out a few of the more prominent features of the pilot on the foam including the ear bulges on the leather helmet, the goggles and the mask, the tie and scarf, and shirt collars.

After marking the features up I began carving with a #11 X-acto. First rounding off the poor blokes head and his ear bulges. Then moving to the face area, start to rough in the mask and goggles. For the most part, WW-II pilot figures are relatively easy to carve because their eyes, ears, hair, and mouth are typically covered up with goggles and helmet. You can do this.

Continue to refine each of the individual features adding more detail each time you make a pass. Some of the refinements might include making the necktie and collar, adding the belts for the parachute, and the straps for the mask. I continually look back at some of the better reference images and my sketches to help me along.

Then I looked around my junk drawer for small pieces and parts to help with the finer detailing. I sized and cut large zip ties to mimic the parachute straps on his shoulders and back. Finally get to use this junk I’ve been hording for 10 years…extra credit. During the trial fit I realized that the tie had made a nice impression in the soft foam and the ridges of the zip tie were in the foam. Done! No need to glue on the ties after all. Found a small disc like piece of plastic for the mask, and then took two pieces of wire to model the air and radio tube coming out to the front of the mask. This type of detailing really helps sell it and takes your pilot figure to the next level. Fun stuff.

Next I decided I wanted the pilot to be looking up and to one side so that when in a fly by on the slope, he can look at the guys on the hill. This is easier than it sounds. I grabbed a blade and cut off his head. The horror. I then put his torso in the cockpit for a trial fit and added his head, rotating it a little at a time until I found the angle I liked. Next I grabbed some five-minute epoxy and glued it in place. After a little trimming it was over.

At some point you will have “enough” detail in your pilot figure and it will be time to move on to the clean up and final sanding. For a small model, you may desire a simple pilot figure. If you have a large-scale ship with lots of detail, you might wish to take more time and have more detail in your pilot figure to match.

Next I started cleaning up the figure with the knife, small files, and sand paper. I didn’t get too picky with my pilot because it is so small.

At this point I started to look through my reference material for RAF uniform and equipment colors. There is a surprising amount of reference material out there.

I painted the entire figure with a latex paint that was somewhat close to the color of the R.A.F. uniform. For this step, the color is not all that important so any color will due. This first light coat of paint tends to show off all the blemishes and faults in your figure so don’t be worried. This is a good thing. Take the time to cut off stray bits and fill in unwanted divots with light weight spackle. If you find big problems with your pilot, this is the time to cut them off, glue on fresh chunks of foam and carve it up again. This is the beauty of working with foam.

Next I painted the uniform sleeves and collar with a grey blue acrylic paint, the Mae West with an orange-yellow acrylic, the helmet is a dark brown to simulate the leather, and on and on. The only special item was the goggles. I wanted them to be shiny and reflective like the real ones. After the initial light blue paint I followed up with a few shiny clear coats. It has the effect I was after.

Next, I added the very fine painting of buttons, and insignia, etc. You will be surprised at how little it will take to make it sing.

At this point I had had enough and the figure looked pretty good. I called it.

A few quick tips to help you along…

Work quickly and don’t concentrate too long on one area or element because it seems to work best to bring along the detail level evenly on the entire figure rather than finishing individual pieces before moving onto the next.
Work on one feature for a short time and then do the same feature on the other side of the figure while it is fresh in your mind.
Always use a sharp X-acto and don’t be afraid to use small files and other tools. There really are no rules to what you can use.
It also helps to add a little detail to the cockpit area such as a seat back, an armor plate, or whatever to help with the allusion. Maybe add a rear view mirror on the top of the canopy for the Spitfire. It all helps and is easy to do. I need to do that as well.

I hope this was helpful and you give it a try the next time you are working on a model with a clear canopy.

Good Luck

More Images…

Reference Images…

Mike Trutwin’s Scratch Built BD-5 and Foam Pilot Figure

Fantastic stuff Mike - thanks.

Nice office! The extra detailing really finishes it up nicely.

My SG-38 and Pilot Figure

This was my first carved pilot. He is bit rough…but he makes the ship work.

My ME109 Pilot Figure

Odd looking but not bad for a one inch tall carving. Again, it sold the illusion.

Details: Created on Friday, 23 November 2007 07:07; Last Updated on Saturday, 19 January 2008 09:30; Written by Webmaster

Gordy's Travels Articles

These articles were written by well known soaring authority Gordy Stahl, who writes for RC Soaring Digest. Re-printed by permission.

Details: Created on Monday, 26 October 2009 21:36; Last Updated on Tuesday, 27 October 2009 08:33; Written by Sloperdude

The chance of having a LiPo fire may be low, but they can happen to you, so what are you doing to protect your car, home and family from a possible LiPo fire? Here is my cheap solution.

I bought a fairly large .50 caliber ammo box from Amazon.com marketplace for $5 plus shipping. Ammo boxes are also available at Fleet Farm, I've been told.

First, drill a hole in the cover that is large enough to pass a Deans connector through it for charging. I used a step drill, which could make a larger hole than any of my other drills. Then I deburred the hole with a sanding attachment on my Dremel tool, to keep from cutting through the insulation on my charging cord.

Next, I set my batteries into the ammo box to see how many dividers I would need to make. Then I cut some Sheetrock that I had to fit the bottom of the ammo box, to insulate it from the heat of a smoking LiPo. This may be overkill, but that's my middle name! Then I arranged my batteries in the box to see how many dividers I would need to make. With dividers in place, if one LiPo ignites, none of the others will be damaged. My next job was to make the Sheetrock dividers, which run the length of the ammo box, and several smaller dividers made from several small pieces of Sheetrock taped together so they won't tip over. All of the dividers should be much taller than the LiPo packs, yet leave just enough room for Ziplock sandbags between the top of the dividers and the lid of the ammo box. Here are the finished dividers and floor. I left them loose so I can change the layout when I buy more LiPos. The photo on the right shows the batteries I'm storing.

Here are the batteries in the box: If I had more batteries, I'd store them vertically, instead.

The last thing you need is some dry sand. If it's damp and a LiPo ignites, the moisture will cause the LiPo fire to accellerate, instead of extinguishing it. LiPo fires are hard to extinguish otherwise, and a standard or chemical fire extinguisher won't work, either.

I filled two Ziplock bags with play sand, zipped them closed and duct taped the seal so it wouldn't open accidentally, and laid them on top of the dividers. If a LiPo goes off, the heat will melt the bag, dump sand on it and extinguish the fire. This won't stop a large quantity of hot, acrid and corrosive gas from venting out of the box, but at least your car or house won't burn down. If you're paranoid, you could always make a vent tube. (Paranoid is my other middle name.)

Finally, here is a video that shows several battery bunkers, one of which is an ammo can without the battery dividers or sand, and two other excellent LiPo fire videos.

Be safe.

Details: Created on Tuesday, 30 September 2003 09:00; Last Updated on Saturday, 19 January 2008 11:24; Written by Ed Berris

It Pays to Keep Learning

by Ed Berris

I do realize that the subject comment states the obvious but I wanted to tell you about my own experience last Saturday.

Larry Sorenson agreed to spend the better part of the day helping Kevin Kavaney to bag his first fiberglass wing. Jack Perecman and I wanted to see what new tricks we could learn so we all went to Larry's house in the morning.

Now, I should say that I have watched as well as laid up my own glass wing but I was not thrilled with my success. I knew it would take a couple ten more times before I felt really comfortable. Mike Martindale was kind enough to work with me to show me the ins and outs of a fiberglass wing lay-up. He makes everything look so easy that I figured I had it knocked and felt confident that I would have no trouble repeating the process in my own shop. I even copied Mike's idea for a lay-up table. I had all the tools, the gadgets, the vacuum pumps. Good lord, I had enough stuff to open a bidness.

The day came for me to lay up some wings. The day ended abruptly when I tried to transfer the wetted out, bias cut fiberglass cloth to my mylars. When Mike did it he had no trouble. When I did it the glass immediately became elongated and no matter how hard I tried I just couldn't get it to the right position on my mylars. It was frustrating beyond belief.

On Saturday I again learned why watching and doing and watching again can really make a difference. Larry employed a neat trick to transfer the bias cut fiberglass glass to the mylars by a simple but very elegant trick. He cuts the planform out of waxed paper. Lightly sprays the waxed paper with 3M Super 77 and then applies the tacky waxed paper to the fiberglass at a 45 degree angle. Next he cuts the glass using the waxed paper as a cutting guide. Using a rotary cutter makes this a very clean and easy process. No snags or pulled threads. Just a clean edge. Now, everything is together in one piece – the cut glass and the waxed paper.

Next, a measured amount of epoxy is applied by roller to the mylars. Once the mylars are covered with epoxy Larry positions the fiberglass/waxed paper glass side down onto the wetted out mylars. Then the waxed paper is carefully peeled away from the glass. A quick pass with a wetted roller completes the process. Naturally, there are more layers of glass and carbon that go onto the mylars but the process is simply repeated depending upon how many layer of glass are used.

Had I simply said: "I've seen people lay up wings before and watched five videos so I know how to do it but I just need practice" I would have never learned this trick.

That's why I always like to see how somebody else does something. It seems like I always come away with a new trick and a better technique.

Photos

Links to construction photos can be found in the photo gallery. Here is a link to the album.

Details: Created on Thursday, 24 January 2008 00:00; Last Updated on Friday, 25 January 2008 10:16; Written by Mike Trutwin

Tips for making your own wing rod tube or ballast tube

I thought I would post a collection of ideas sent to me when I was asking for help building some Kevlar wing rod tubes for my Supra. I had read a few techniques before I started, but ran into some problems along the way. In my situation I was making a Kevlar tube that would be cut up into 4 individual wing rod tubes. I started by waxing the .375 dia. x 12” long carbon fiber rod several times. I then wrapped the rod one time with waxed paper with about 1/16” overlap. I then wrapped 5oz bias Kevlar 3 times around. I then wrapped several layers of waxed paper around that and then some stretched masking tape over that. (Just a note here. In the Supra, this tube will be glued into a solid basswood block to carry loads to the spar caps.) The biggest question I had at the time was what kind, and how many wraps of material was needed to create the right tolerance for a snug fit. I felt I wanted a snug fit so opted for just one layer of waxed paper. In the case of a ballast tube, you would want to increase that quite a bit.

All went well up to the point of getting the rod out from inside the cured tube. I tried many things but here is what finally worked. First I post cured the tube at 140 degrees for 24 hrs. The tube was much harder after it came out of the oven. Still stuck on the CF rod good though. I drilled a hole the size of the CF rod through an oak board. Mounted that in the vise. Aligned the rod & tube assembly over the hole so just the tube would catch, then drove the rod through from the top. The end of the tube took a little mashing but that got cut off anyway. All the pieces finished up fine, and the fit is just right. Maybe a bit on the tight side.

Kevlar Tube

Here are a few suggestions that were sent to me for constructing a tube:

Next time use at least three wraps of waxed paper and DO NOT use anything to stick the cloth to the waxed paper.

A better thing to use instead of waxed paper might be 3" wide clear packaging tape.

One trick I use is to run a piece of kevlar tow lengthwise in the layed up kevlar. Leave a tag end dangling out. After the epoxy is set, the tag end allows you exert more force to pull the box off of the joiner.

I made my joiner tubes from ½" carbon sleeve stretched over the rod and wet out. I melted some white candle lights in the oven at 225F in a trough made from alu foil and placed in a pan to catch leaks and submerged the rod in the melted wax. When I took the rod out I held it vertical to let the excess wax run off until the wax was hardened. After the epoxy was dry I cut off ½" in one end of the tube with a knife so I could get a hold on the rod inside with pleiers. Then I set it in the oven at 225F for 10min to melt the wax and pulled the rod out with a pleier. I preheat the oven every time. After some light sanding with 320 the rod fits snug inside the tube.

I keep posting this whenever I see people having release problems with tube shaped mandrels. The following talks about an aerosol based mold release that builds a wax coating on the mandrel just like the candle wax in a previous post. The old version was #3270 Ready Release made by Crown. The newer stuff still carries the Crown name on the label but Crown was bought out by Aervoe and now the name is Reliable Mold Release for Epoxy, #3470. It will quickly leave a nice even coat of wax and then when its time to release the part, you simply put it in a warm oven, a tub of hot water, or just run hot tap water over it. The wax melts and the part comes right off.
http://www.rcgroups.com/forums/show...ady#post6854964

I attached the mylar to the carbon rod with a thin layer of vaseline. The tub slid off with no problem. This was after I did a practice tube around a wood dowel where I used wax to attach the mylar. It was a problem to get that one off and ended making a mess out of the dowel.
http://www.rcgroups.com/forums/showthread.php?t=632908

I have read that olive oil works good as a release and using balloon mylar as a spacer.

Work in shorter lengths. Instead of working with the 12” piece, cut it in half and do two separate layups. There will be less friction when it comes to removing the rod.

Start with a rod that is very smooth and perfectly round. No scratches or dings. Make sure the rod is longer than your tube by a little bit. Bevel the ends of the rod before the layup if possible. Put a few extra wraps of fabric at one end of the tube so as to have something to grab onto or a strong lip to pound against for removal. The extra wraps would get cut off after.

Here are a few ideas to remove a stuck rod:

Let the rod cure for at least 48 hours before trying anything. Partially cured epoxy is fairly flexible and will not part cleanly from a form that has no draft. Then try placing the part in the freezer until it's pretty cold. Remove the tube from the freezer and whack the inner tube. This 'should' get the part to release. Now a little heat on the outer surface should allow you to slide the tube off the form. Also. a little high pressure air blown between the two tubes should help.

Have you heated the thing up? Put the thing in your oven on 250 degrees F. This makes the wax go liquid and then you can probably pull the tube off the mandrel. Of course, you have to use gloves for that (or be really quick about it).

Have you tried placing the part in warm water? Also, if you have an air compressor you can try shooting air from the end of the rod. Try to aim the stream of air between the rod and the layup.

Drill a hole in a piece of oak block the size of the wing joiner rod. Heat up the kevlar tube a little, and lightly tap the rod out through the hole in the oak block.