I just began building the Proctor Mini Antic Biplane about a week ago and thought it would be fun to share my build with the community and solicit ideas when needed. My father in-law gave me this kit (circa ~mid 80s I think) a few years ago and I've been anxious to begin the build, especially since I've heard so many great things about the Proctor kits and the Antic's flight qualities. The Antic is available in a few different sizes and styles, but the kit I have is the 40 size biplane. If you would like more information on the Antic here's a link to Proctor's website: http://www.proctor-enterprises.com/p...e/ant_bipe.htm

This Antic will be powered by the E-Flite Power 46 brushless outrunner so I will be doing a glow to electric conversion. I'll be using a proven electric setup so I'm not too concerned about that right now and am instead focusing on the build. The one nice thing about the electric power system is that I can create a more scale looking front end. The typical (non-cowled) way for mounting a glow engine on an Antic leaves a lot to be desired in my opinion, so by being able to fabricate a more scale front end is ideal and has given me a lot of ideas.

I love the looks of the Curtis Jenny and since the Antic is not a scale model, I will be taking liberty to do a few modifications to make the Antic look more like a Jenny. I'll discuss my planned modification in more detail in a later post, but here are some ideas going around in my head:
1. Addition of a Jenny style cowl - Another modeler that goes by steve crewdog posted a great thread on his e-conversion of an Antic Mono plane and recreated a Jenny looking front end. I'll be doing something very similar and have already ordered the dummy engine kit that Proctor produces for their engine. Here's a link to Steve's build thread: http://www.rcgroups.com/forums/showt...83#post8544597
2. Turtle deck - I'll be making the top of the cowl 'domed' like it is in the Jenny, and thought that it would look best to continue this 'dome' by adding a turtle deck that tapers to the vertical fin. The Antic normally has an open fuse at the tail, so I'm not sure if by adding a turtle deck I'll want to keep it open. I'm build as if I am keeping it open (i.e. I'm staining the wood) so I can make a decision further down the road.
3. Clipped bottom wing - The wing has a nice stager, like the Jenny, but I'm considering clipping the bottom wing by two ribs on either side. This will make the wingspan on the lower wing slightly smaller than the wingspan on the top wing. The Jenny has a pretty significant difference in top/bottom wingspan, but I think that by clipping the wing by just two or three ribs on either side will give the Antic a more graceful look.
4. Mod of tail surfaces - Here's where I'm really going out on a limb... With the mods described above, the plane is really starting to resemble a Jenny rather than the Eindecker style the Antic normally captures. To complete this transformation all I would need to do is redesign the tail surfaces to look more like a Jenny. I found some plans online that I can size and build to if I decide to go this route.

I'll discuss the mods as they come up, on to the build...

Steve

Steve: Be aware of, and watch out for, the shift it CG from wings of equal area, to ones of unequal area. This is from Lennon, and I have confirmed that it is consistent with several planes from different manufacturers.

Les

The first step is to cap each of the 36 wing ribs, a very tedius task. I tried using pinning things in place but I couldn't get the caps tight engough to the rib. Luckly the kit comes with one rib already capped, so I made a jig by tracing the completed rib on a 1/4" thick piece of balsa and cut it out with my scroll saw. I hinged one side of the jig with a CA hinge and can lock it in place with two clamps. The nice thing about the jig being made from balsa is that the clamps really tighten the jig down. I made a few marks for alignment and since the jib has no base, I'm able to glue both sides at the same time. I'm just using Elmer's glue and it seems to be going well. I now have about 6 ribs done but there are still many to go.
Steve

Les - Thanks for the reminder, I would have totally forgotten about this! With 1133 sq in of wing area, I'm not concerned with the small loss of area, but I'll have to recalculate CG.

Looking good, Steve. I'll follow along on your build of this neat 'ole model.

Joe

Once I got the ribs going, I started on the fuse. (I'm a week into the build so I'm still catching up on the thread) There are an amazing number of pieces in this kit, but the build is actually fiarly simple and very fun. I really enjoy building stick fuses, they just look so pretty. I first stained the rear fuse pieces with Proctor's Mahogany stain, and then piece by piece, the fuse side started to come together.

Things are really progressing now that I'm getting the knack for how the kit goes together. The second fuse side only took a day to build. The two sides are the same except the plywood veneers are added to opposite sides. The one step that I wasn't too sure about was installing the cross bracing which is made of small diameter bamboo. The first step was to paint it black (you can see it drying upright in a few pictures). While the paint was drying I used my dremel tool with a small drill bit to make a small hole in each corner where the cross bracing is to be installed. The bamboo cuts really easily with scissors. I cut it to length so it wouldn't bind and thanks to the small holes, it held in place even before the glue was added. I used Duco cement for securing the bracing in place. Okay, now I have two fuse sides completed!

I'm up to my current status now so more building to come in a couple days...

Steve

Steve, you are making great progress! The quality of the kit looks excellent. I may have to do a Proctor WWI after all!

Where did you get that mini clamp from the pic in post #6? I've got to have a set!

Hi Tony - The mini clamp is from Sears (I use it all the time) and the mini cut off saw is from Harbor Freight (I use this a ton as well).
Steve

In my quest to stylize my Antic with some features of the Jenny, I checked out the Jenny on display at the Smithsonian Air and Space museum in DC. The nice thing about the Jenny that's on display is that it is cleaned up but not totally reconditioined. There were also some great Fokkers on display as well and the earlier models really resemble the stock Antic mono plane. One interesting observation a friend made was that the open fuse was typically used in the early years, but once biplanes were being developed the fuse was typically covered. This helps support my proposed mod of adding a turtle deck and covering the fuse, like it is in the Jenny.

The pictures don't do it justice but they will help me with the mods.

There were also some great models on display that I thought I would share since the built up structure is visable and the structure appears to be scale.
Steve

Both sides are complete now and I've begun installing the internal structure to one side. This step is taking some time since I need to make sure everythng is squared up and dry before moving onto the next piece. One thing I noticed is there is no right thrust on this model, but there is down thrust. Does anyone know if right thrust should be added to this model? If I don't add it I can always add a rudder to throttle mix to compensate.

I visited our great local hobby shop, Hobby Hangar, and picked up a Hanger 9 motor mount. I need to think more about how the front end should be designed for electric power but I'm comfortable proceeding with more construction for a bit longer. One option I'm considering is permanently securing the cowl sides to the firewall and using this as a frame for a motor box (I wouldn't then use the Hanger 9 motor box). I'll cut a hole in the firewall for the battery once I get the design nailed finalized.

Steve

Your lucky you are so close by the Smithsonian. I was there last year but that area was undergoing a face lift so the Jenny was not there and I hate I did not get to see it. I like your idea to change the Antic some and have thought of bashing it into some WW1 type plane too. Looks good!

Steve, looking good, I have the full size Antic Bipe that I will be converting to electric, the idea of a Jenny style cowl did not occur to me, I was just going to go round but may reconsider. I have to agree on the number of pieces, I have never seen a box with so many different pieces.

In doing the ribs I used my magnetic building board (a great tool, by the way) to set up a jig that allowed me to glue top and bottom at same time, using CYA. It still took a while to do them all.

I have mine about 95% finished (have to cover the bottom wings and do the wing rigging, and install power system), and felt I would never do this again, but if I could pick up a Mini-bipe kit somewhere, I probably would have to give in and get it, as the full size looks great and the Mini has to look at least as good...Pete

The two fuse sides are now joined and all cross bracing is complete. The instructions call for some internal diagonal bracing but I'm not sure if this is really necessary since I'll be adding a turtle deck which should provide some additional strength. The fuse came out nice and straight and is very strong, and the stained wood and black cross bracing look beautiful. I'm going to start drafting up the new fin design so I can determine how far back to carry the turtle deck.
Hope everyone is have a great holiday week.
Steve

As I'm starting to think about how to redesign the tail pieces, I'm first curious how the Antic geometry compares to the Jenny. Unfortunatly I only have a really small plans printed for a Jenny (1/47 scale!), but it should be enough for me to calculate lengths and areas. My goal in redesigning the tail pieces is to try to match the area of the stock Antic, or at least not be smaller. Just looking at the Jenny I can see that it has a much larger rudder than the stock Antic but the vertical stab is really small compared to the stock Antic. I think it's best that I try to match total area of the vertical fin rather than each piece. The horizontal stab and elevator look pretty close, but let's start looking at numbers:
Here are the dimensions of the Antic:
1/6 Scale Antic Antic Scaling Factor Antic Full Scale
Wingspan top (in) 56.75 6 341
Wingspan bottom (in) 56.75 6 341
Wing Area (sq in) 1133 36 40788
Fuse Length (in) 40 6 240
Total Length 44 6 264
Vertical Stab Area (sq in) 21.35 36 769
Rudder Area (sq in) 21.9 36 788
Horizontal Stab Area (sq in) 88 36 3168
Elevator Area (sq in) 40.8 36 1469


Here are the dimensions of the Jenny from the plans I found:
1/47 Scale Jenny Model Jenny Scaling Factor Jenny Scale
Wingspan top (in) 11 46.66 513
Wingspan bottom (in) 8.62 46.66 402
Wing Area (sq in) 24.22 2177.16 52731
Fuse Length (in) 6 46.66 280
Total Length 6.9375 46.66 324
Vertical Stab Area (sq in) 0.235 2177.16 512
Rudder Area (sq in) 0.815 2177.16 1774
Horizontal Stab Area (sq in) 1.914 2177.16 4167
Elevator Area (sq in) 1.5 2177.16 3266

So what I found from this is that the Jenny is a larger airplane so I need to scale it down a little. Here's the ratio of Antic to Jenny:
Antic to Jenny ratio
Wingspan top (in) 0.6634
Wingspan bottom (in) 0.8466
Wing Area (sq in) 0.8795
Fuse Length (in) 0.8573
Total Length 0.9031
Vertical Stab Area (sq in) 1.2257
Rudder Area (sq in) 0.6666
Horizontal Stab Area (sq in) 0.8719
Elevator Area (sq in) 0.6706

I'm thinking it is best to scale to wing area and fuse lenth, and luckly they are pretty close. This means I'm going to reduce the Jenny to 86% so it is closer to the Antic size wise. After scaling the Jenny to 86% and then further scaling it down to 1/6 scale, this is what I came up with:

1/6 scale 86% Jenny 1/6 Scale Antic
Wingspan top (in) 74 56.75
Wingspan bottom (in) 58 56.75
Wing Area (sq in) 1083 1133
Fuse Length (in) 40 40
Total Length 46 44
Vertical Stab Area (sq in) 11 21.35
Rudder Area (sq in) 36 21.9
Horizontal Stab Area (sq in) 86 88
Elevator Area (sq in) 67 40.8

Okay, this was a pain but I think it tells me that if I was to build Jenny style tail sections based on my 1/6 of 86% scale, my combined vertical stab and rudder would be slightly larger than the stock Antic and the horizontal stab would be about the same and the elevator would be more than 50% larger than the stock Antic. I could scale them down further I guess to get closer to the stock area, but I would like to see how this look so I'm going to draft up some plans based on this scaling. I'm not positive that what I'm doing is legit, so any comments are welcome. Attached is a tab delimited version of the Excel file I developed to do the calculations.

thanks,
Steve

Steve, I think the areas of your Jenny-style tail look good. Also check to make sure the dimensions will be about the same size so it will look good, but the areas are fine. When sizing the tail feathers, you are looking for area X moment. So if the tail is in the same place, the area must be about the same to achieve the same "tail volume." This will guarentee the same control as the original design.

I think you are good, but just to make sure, can you post the length and width of your "new" vertical and horizontal to compare them to the original design?

Here is a picture from an old RCM of an Antic bipe converted into an Albatros (?) two seater.

Jim

Great picture, Jim, thanks for sharing!

I mounted the landing gear last night and soldered the two pieces together with copper wire and solder. I used my wife's creme brule butane torch to solder the joint and it worked really well (as long as she never finds out). I'll be removing the LG to paint them black. The instructions call for mounting the tail skid but I'm going to hold off on that until after the model is covered because I think it will just get in the way.

In the one picture below you can see my draft design of the Jenny style tail feathers resized for the Antic. The rudder looks pretty good, but I may move the hing line aft by about 1/2" to increase the vertical stab area and reduce the rudder area so it is closer to stock size. The horizontal stab looks really big, but it is big on the Jenny so this makes sense. The horizontal stab matches the stock Antic area pretty much exactly, but the Jenny style elevator is much larger than stock so I may reduce the chord of the new elevator by an inch or so.

Tony - I'll post some measurements tonight. The aerodynamic center of the Jenny style vertical stab and rudder are more aft than the stock Antic, do you think this would be okay? Maybe we can meet up this week and look at the plans together.

Steve

Tony - Here are the measurements:
Antic:
Horizontal Stab:
Width at LE - 1 7/8"
Width at TE - 18"
Chord at center - 8 1/2"

Elevator (half)
Width - 8 7/8"
Chord - 2 1/4"

Vertical Stab:
Chord at base - 3 3/4"
Chord (max) - 4 3/4"
Height - 5 1/2"

Rudder:
Chord - 3"
Height at leading edge - 7 3/4"


Here are the measurements for the Jenny style tail:
Horizontal Stab:
Chord - 5 7/8"
Weidth at top before curve begins - 9 3/4"
Width at TE - 16 3/8

Elevator (half):
Chord - 4 15/16"
Width at LE - 7 3/4"

Vertical Stab:
Length - 5"
Height - 4 1/4"

Rudder:
Chord (max) - 5 7/16"
Height at LE - 6 3/8"
Height at peak (measured from line extended from bottom of fuse) - 8 9/16"


Steve

Here are pictures of the stock Antic and Jenny style tails which I fabricated from cardboard to get a visual on how things look. I'm going to think about things a little more before I finalize the tail, but my initial reaction is to make the following changes to the Jenny style tail: 1. reduce chord of elevator halves by 1 inche to get closer to the stock area, and 2. decrease the pointeness of the top of the rudder slightly and beef up the bottom slightly (I think my design is more pointed than it should be). I bought a bunch of stringers so once I get closer on the tail design I'll be able to start building the turtle deck and tail surfaces.
Steve

I finalized the drawings for the tail section and stained the wood for the turtle deck and tail stringers so I'm ready to start building again. These parts didn't really need to be stained since they will be covered but I love the look of stained wood and thought it would help the structure show through the covering. The tail sections are 3/8" thick at the hinge line and taper at the LE, tip and TE to basically form a slight airfoil. I also painted the LG parts black.
Steve

i.

Your Mini-Antic looks very nice. You seem to be a meticulous builder. I have an Antic monoplane on the way from Proctor and had a couple questions, if you don't mind.

1. What type of paint did you use on the bamboo cross-bracing for the fuselage?

2. Did you find that the paint interfered with the adhesion of the Duco cement when they were put in place. As I recall, Proctor specified Duco because it shrinks when it cures and the shrinkage puts the bamboo bracing in tension. I plan to use the Proctor lacquer-based stain on the spruce longerons. According to Proctor that stain will not impede adhesion of cements. Hope so.

3. Are you going to strip-plank the turtle deck? That should be beautiful.

Good luck (you probably won't need luck) with your build, and thanks for your time.

Hi lmcnii, thanks for the complements. This is my first Proctor kit and it is beautiful, so I'm sure you'll be impressed as well. To answer your questions:
1. I tried two types, the first being Tester's enamel that I had on hand that is typically used on plastic models. I wasn't sure if it would work but it adhered well and didn't bleed when I glued it. When I needed to paint more bamboo I thought I would do one better so I picked up some black acrylic paint from the hobby store. It applied to the bamboo easier but since it is water based it would rub off where the duco cement was applied if I wasn't careful. It's easy enough to go back and touch up, but I think I like the results of the enamel better.

2. The Duco cement seems to stick to everything so I didn't have any problems with it bonding to the stained or painted surfaces. I actually used Elmer's glue on most of the model so far and that also didn't have any problems bonding the stained wood.

3. Yup, but it will be open. I'm going to use 9 stringers laid on top of a few formers to build up the turtle deck. I'm concerned about tail weight so the stringers are pretty thin and there will be space between each stinger, just like the scale Jenny.

Have fun with the build and please share any pics!
Steve

i.,

Thanks for the reply.

I did not mention it, but your jig for cementing the cap-strips to the ribs is a nice touch also. Making one will probably be the first step for me when I get my Antic.

Hope your build continues to go well.