Aviatik DI build
08-19-2010, 01:21 PM
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Aviatik DI build
This newbie to gas has just finished the initial two hours of break-in at idle on the DL50. While it is very easy to start, I’m just nervous enough with it to be very careful around it, ( and that’s a good thing). The oil soaked pants are in the wash, (good thing my wife is away this week), and I thought I would start this thread. I like the design end of modeling and the designers of these large models seem to have a wide range of approaches.
This is my first “gasser” build. I‘ve had IMAA sized planes – 81” PZL I/II, and currently fly an 86” Dewoitine D500 and 68” Nieuport 12, (all electric), but last summer, I won a DL50 at our annual Giant Scale meet. Much to the shock of my clubmates who have seen me fly only electrics for 20 years (!), I didn’t sell it on the spot, (and there were healthy offers), but took it home with plans to build a large WWI model.
A friend and I went to Rhinebeck a few weeks later and that confirmed my determination to build an “inconveniently large” model. I measured the van with the seats out, and I should be able to do it. So what model?
I looked long and hard at the Balsa USA kits and talked extensively to the guys in the trailer at Rhinebeck. They were very helpful but while I was tempted to pick up a kit, I didn’t for two reasons. First, I like designing my own planes rather than building from someone else’s. It also ensures that I’m not building what everyone else is, (this is sometimes a dangerous choice!) Secondly, while there are a ton of BUSA planes flying very well at Rhinebeck, the out-of-the-box kits are semi-scale and I’d feel a need to modify them. Why buy a kit if you are just going to re-draw and re-engineer it? So the search for a subject and information started. I was also mining the internet for information on gas engines and large gas models as I have no experience.
I’ve built a number of Nieuports and very seriously considered the Nieuport 27, even enlarging parts of the Replicraft plans to 30%. In the end my choice was the Austro-Hungarian Aviatik DI fighter of 1917-18. The nose is not absurdly short, (ala Sopwiths), and it has a long tail moment and a good sized stab. The landing gear seems neither too far forward nor aft. The large radiator should help with cooling. The fuselage can be covered in 1/64” ply, (authentic) and the wings have plenty of area. Rigging is straight forward and is cable rather than RAF wire, (although I am hoping for a very practical model rather than a museum piece). Plus there are a variety of colour schemes available.
Size was determined by available wheels, (in the common tradition!) – 31.25% to use Dubro 9 1/3” vintage wheels. They can be trimmed and sanded to improve their looks, but more importantly are very solid. I looked at http://www.herbiewheels.de/index3.htm Considering value for money, these are much better than the Dubros, but I have heard of problems with models over 20lb. Perhaps someone can clarify that for me.
Anyway, at 31.25%, (or 1/3.2), the Aviatik comes in at 99” span, 84” long, and just under 36” high. Area is 21 sq. ft. (3023 sq. in.). My target weight is 24lb., plus any balance weight. I have started drawing using the Steve Simkin drawings in the DataFile and have the outlines finished. (There is a lot of paper with something this size.) For other references, I have the JaPo book, the old Profile, as well as Peter Grosz’ (et.al) book on A-H Army Aircraft. There are also some excellent pictures of a display of a DI in Vienna.
Below are some net pictures of the airplane. I am still considering colour schemes but am leaning towards the “hexagonal” ones.
Martin (who is hoping for lots of input on this project)
This is my first “gasser” build. I‘ve had IMAA sized planes – 81” PZL I/II, and currently fly an 86” Dewoitine D500 and 68” Nieuport 12, (all electric), but last summer, I won a DL50 at our annual Giant Scale meet. Much to the shock of my clubmates who have seen me fly only electrics for 20 years (!), I didn’t sell it on the spot, (and there were healthy offers), but took it home with plans to build a large WWI model.
A friend and I went to Rhinebeck a few weeks later and that confirmed my determination to build an “inconveniently large” model. I measured the van with the seats out, and I should be able to do it. So what model?
I looked long and hard at the Balsa USA kits and talked extensively to the guys in the trailer at Rhinebeck. They were very helpful but while I was tempted to pick up a kit, I didn’t for two reasons. First, I like designing my own planes rather than building from someone else’s. It also ensures that I’m not building what everyone else is, (this is sometimes a dangerous choice!) Secondly, while there are a ton of BUSA planes flying very well at Rhinebeck, the out-of-the-box kits are semi-scale and I’d feel a need to modify them. Why buy a kit if you are just going to re-draw and re-engineer it? So the search for a subject and information started. I was also mining the internet for information on gas engines and large gas models as I have no experience.
I’ve built a number of Nieuports and very seriously considered the Nieuport 27, even enlarging parts of the Replicraft plans to 30%. In the end my choice was the Austro-Hungarian Aviatik DI fighter of 1917-18. The nose is not absurdly short, (ala Sopwiths), and it has a long tail moment and a good sized stab. The landing gear seems neither too far forward nor aft. The large radiator should help with cooling. The fuselage can be covered in 1/64” ply, (authentic) and the wings have plenty of area. Rigging is straight forward and is cable rather than RAF wire, (although I am hoping for a very practical model rather than a museum piece). Plus there are a variety of colour schemes available.
Size was determined by available wheels, (in the common tradition!) – 31.25% to use Dubro 9 1/3” vintage wheels. They can be trimmed and sanded to improve their looks, but more importantly are very solid. I looked at http://www.herbiewheels.de/index3.htm Considering value for money, these are much better than the Dubros, but I have heard of problems with models over 20lb. Perhaps someone can clarify that for me.
Anyway, at 31.25%, (or 1/3.2), the Aviatik comes in at 99” span, 84” long, and just under 36” high. Area is 21 sq. ft. (3023 sq. in.). My target weight is 24lb., plus any balance weight. I have started drawing using the Steve Simkin drawings in the DataFile and have the outlines finished. (There is a lot of paper with something this size.) For other references, I have the JaPo book, the old Profile, as well as Peter Grosz’ (et.al) book on A-H Army Aircraft. There are also some excellent pictures of a display of a DI in Vienna.
Below are some net pictures of the airplane. I am still considering colour schemes but am leaning towards the “hexagonal” ones.
Martin (who is hoping for lots of input on this project)
08-19-2010, 02:24 PM
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RE: Aviatik DI build
Nice project Martin, I see you have picked the same scale I used for the Aviatik 30.40. I see you have projected 24lbs as your overall target weight. I built the 30.40 pretty light and it only had one wing and it still got to be 27lbs. after adding 4 1/2 lbs of nose weight. Don't be surprised if your total weight comes in at around 30+lbs. Looking forward to your build.
08-19-2010, 02:47 PM
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RE: Aviatik DI build
Martin,
Looking forward to seeing more!. The D.I ranks up there with the Fokker DVII as having the most space in which to hide your engine. There is a D.I at the Museum of Flight near my house so I think I have pictures if you need any help.
Blue Skies!
John
Looking forward to seeing more!. The D.I ranks up there with the Fokker DVII as having the most space in which to hide your engine. There is a D.I at the Museum of Flight near my house so I think I have pictures if you need any help.
Blue Skies!
John
08-19-2010, 03:01 PM
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RE: Aviatik DI build
Definitely go with the hexagon school scheme! It'll mess with the minds of those who've only seen lozenge covered DVIIs! 
What's that arm on the UC sub-wing?
What's that arm on the UC sub-wing?
08-19-2010, 04:05 PM
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RE: Aviatik DI build
I have read your build carefully John and perhaps I am overly hopeful. I figure on 24lb. PLUS any balance weight - that very well may put me close to 28lb anyway,We shall see. From what I have read, at 30lb, I will still have enough power, just not a lot of excess. Perhap I would be smart to put the firewall back an inch or two incase I need to re-engine it.
Yes, there is a lot of room in the engine bay, John. That strikes me as a plus for a newbie. On the other hand, I am thinking about a canister muffer to tame the awful racket. Consider it residue from my electric experience! Most people have trouble with the basic muffler, (exhaust manifold really), that comes with the engine. They break easily.
Don, I believe the thing on the U/C is a claw brake. It was on the earlier models. I like it, and the earlier rounded radiator, but I am leaning towards the later version with the machine guns moved back to infront of the pilot, and the cut down forward decking. The pilot location on the early models looks quite bizarre - top of the head level with the top of the cowling! He had to lean sideways just to see where he was going. The later ones were much more conventional. See below
Another great thing about A-H hexagons is that they were PAINTED! So off-scale models, (ie other than 1/4 or 1/3) are perfectly practical.
Martin
Edit - just realized that the picture included here has both a rounded rad and the claw brake! I'll have to check, but I think both are wrong. The colours look reasonably close though.
Yes, there is a lot of room in the engine bay, John. That strikes me as a plus for a newbie. On the other hand, I am thinking about a canister muffer to tame the awful racket. Consider it residue from my electric experience! Most people have trouble with the basic muffler, (exhaust manifold really), that comes with the engine. They break easily.
Don, I believe the thing on the U/C is a claw brake. It was on the earlier models. I like it, and the earlier rounded radiator, but I am leaning towards the later version with the machine guns moved back to infront of the pilot, and the cut down forward decking. The pilot location on the early models looks quite bizarre - top of the head level with the top of the cowling! He had to lean sideways just to see where he was going. The later ones were much more conventional. See below
Another great thing about A-H hexagons is that they were PAINTED! So off-scale models, (ie other than 1/4 or 1/3) are perfectly practical.
Martin
Edit - just realized that the picture included here has both a rounded rad and the claw brake! I'll have to check, but I think both are wrong. The colours look reasonably close though.
08-19-2010, 10:33 PM
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RE: Aviatik DI build
TAIL CONSTRUCTION
Here's a period drawing of the stab, (the fin and rudder are of similar construction). The original was made of a single tubing section, as opposed to the ribs made of several thinner tubes as used by Fokker.
My thought is that this could be best built with carbon fibre tubing. I weighed some .230 CF tubing I have and compared it to 1/4 X 1/2 Balsa - just a quck and dirty comparison as this is the size used in the BUSA kits. The CF is about 10% heavier but MUCH stiffer and stronger. Also, there would be less structure with the CF. Curved sections could be made from laminated basswood. Joints may be strong enough with JB weld or I could insert wood plugs and drill pins into them for extra security. The original had a curved airfoil, but I think a flat section will be fine, (and I can use the CF as opposed to figuring out strong, thin, curved ribs).
Hinges will be strap type with wood edges for the covering. Are these type available from Glenn Torrance? I'll probably build my own. I haven't figured out the control horns yet.
Time to do some experimenting.
Martin
Here's a period drawing of the stab, (the fin and rudder are of similar construction). The original was made of a single tubing section, as opposed to the ribs made of several thinner tubes as used by Fokker.
My thought is that this could be best built with carbon fibre tubing. I weighed some .230 CF tubing I have and compared it to 1/4 X 1/2 Balsa - just a quck and dirty comparison as this is the size used in the BUSA kits. The CF is about 10% heavier but MUCH stiffer and stronger. Also, there would be less structure with the CF. Curved sections could be made from laminated basswood. Joints may be strong enough with JB weld or I could insert wood plugs and drill pins into them for extra security. The original had a curved airfoil, but I think a flat section will be fine, (and I can use the CF as opposed to figuring out strong, thin, curved ribs).
Hinges will be strap type with wood edges for the covering. Are these type available from Glenn Torrance? I'll probably build my own. I haven't figured out the control horns yet.
Time to do some experimenting.
Martin
08-20-2010, 08:09 AM
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RE: Aviatik DI build
Martin, don't wast your time "re-inventing the wheel", the Glenn Torrance struts and hinges are pretty much perfect. Use his method for making the l/g legs too. The JB Weld is very strong. After my Aviatik 30.40 crashed (hard) only one or two JB Weld joints came apart. The "J" bolts will save you time also. None of those broke or came apart from the crash either. I want to mention that the original construction photo's you are showing came from my 30.40 build thread I believe? They were provide by Koloman Mayrhofer of Craftlab, Vienna Austria. Let me know if I am wrong here. I don't have a problem with you using stuff from my 30.40 build just want to give credit to those who deserve it. I have some better photo's of the D1 at the Vienna technical museum so If you want them send me a PM with your e-mail address. If you also would like the 31.25 scale instrument faces let me know.
08-20-2010, 12:14 PM
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RE: Aviatik DI build
Thanks John.
I do plan on using the Glen Torrance strut material. I love how easily a piece of 3/16 is epoxied into the end. I've bent up 3/16" spring steel landing gears and while it might have help build character, I don't mind giving it a miss.
I think I've seen the hinges, but they aren't on his website. Do you have a reference for them?
I have the photos from here: http://www.idflieg.com I'd love to have any others you would be willing to send. Similarly, hi-res instrument faces would also be welcome. Have you seen : http://www.aerocockpit.com
The drawing was a download from the net of the original so I think copyright is OK. But I lost the original poster. Thanks for clearing that up. I do appreciate that we need to give credit to the people who make it available to us. I think we get much too sloppy with "free" information and in an effort to help out fellow modellers, it is so easy to scan something. In the long run we will all suffer the consequences.
Martin, (off his soapbox again)
I do plan on using the Glen Torrance strut material. I love how easily a piece of 3/16 is epoxied into the end. I've bent up 3/16" spring steel landing gears and while it might have help build character, I don't mind giving it a miss.
I think I've seen the hinges, but they aren't on his website. Do you have a reference for them?
I have the photos from here: http://www.idflieg.com I'd love to have any others you would be willing to send. Similarly, hi-res instrument faces would also be welcome. Have you seen : http://www.aerocockpit.com
The drawing was a download from the net of the original so I think copyright is OK. But I lost the original poster. Thanks for clearing that up. I do appreciate that we need to give credit to the people who make it available to us. I think we get much too sloppy with "free" information and in an effort to help out fellow modellers, it is so easy to scan something. In the long run we will all suffer the consequences.
Martin, (off his soapbox again)
08-20-2010, 12:40 PM
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RE: Aviatik DI build
Martin, you can reach Glenn here: [email protected] Just tell him what you want and he'll help you out. Be careful with the instruments. There were differences between German and Austro-Hungarian instruments. My instruments were made from photo's and drawings of Austro-Hungarian instruments used by Aviatik. Give me your e-mail address and I'll send more stuff.
08-20-2010, 12:58 PM
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RE: Aviatik DI build
Slight change of plans. The CF tubing I thought was going to work so well failed the squeeze test. I was gluing it up and playing around with it when I realized that a firm sqeeze would crack the tube and that the crack would travel easily the length of the peice. So out came some tubing from CST - much better but quite a bit heavier, (nothing is free). I calculated it would make the stab about 7 oz. prior to covering. That strikes me as a little heavy, so perhaps I'll go the "BUSA" construction route - if nothing else, than to get a comparison point.
Martin
Martin
08-20-2010, 01:08 PM
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RE: Aviatik DI build
ORIGINAL: Nieuport nut
Slight change of plans. The CF tubing I thought was going to work so well failed the squeeze test. I was gluing it up and playing around with it when I realized that a firm sqeeze would crack the tube and that the crack would travel easily the length of the peice. So out came some tubing from CST - much better but quite a bit heavier, (nothing is free). I calculated it would make the stab about 7 oz. prior to covering. That strikes me as a little heavy, so perhaps I'll go the ''BUSA'' construction route - if nothing else, than to get a comparison point.
Martin
Slight change of plans. The CF tubing I thought was going to work so well failed the squeeze test. I was gluing it up and playing around with it when I realized that a firm sqeeze would crack the tube and that the crack would travel easily the length of the peice. So out came some tubing from CST - much better but quite a bit heavier, (nothing is free). I calculated it would make the stab about 7 oz. prior to covering. That strikes me as a little heavy, so perhaps I'll go the ''BUSA'' construction route - if nothing else, than to get a comparison point.
Martin
09-08-2010, 10:01 PM
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RE: Aviatik DI build
Just so no one thinks this has stalled - here's a shot of my draughting table with the Aviatik underway. I enjoy drawing on paper so the logic behind AutoCad falls largely on deaf ears! I do realize the advantages of CAD, (I took a course last winter and did pretty well), but there is nothing like seeing it full size, for me, to get a sense of the engineering. I ponder a lot, draw a line or two, step back and ponder some more. Put some tunes on the turntable, (yes I still have mine), and I'm happy for hours.
A friend has a BUSA Pup and I refer to those plans frequently for wood sizes. I am surprised how lightly it is designed.
The original Aviatik airfoil is rather bizarre so I spent a lot of time looking for an alternative. After much consideration, I decided on a Goe 124 airfoil. It is suitably thin but still thick enough for adaquate spars - 1/4 X 3/8 bass caps with 3/8 X 3/8 balsa webbing. I found some pretty light and straight doweling at Home Depot - 3/8"dia and as light as basswood. TE will be 1/16 X 1 1/4 ply with a balsa cap.
The fuselage is rather large. The 50cc engine will be mounted on a 1/2" ply firewall, braced with 3/4" triangular stock to a 1/16" ply box that forms the forward fuselage doublers. The fuselage is made from 1/4" basswood longerons and balsa verticals and cross pieces. The forward fuselage is 1/4" balsa sheet. The whole fuselage gets covered with 1/64" ply, - acres of it. I figure I will get a little left over from two 4' X 4' sheets of it!
All struts will be GTM tubing of various sizes and 5/32" wire inserts that fit into ply mounts in the fuselage.
The engine cowling is large, and I plan on the whole thing being removeable. The radiator may stay in place or be attached to the cowling.
This weekend is Rhinebeck and a friend I are looking forward to seeing some of the models, and modellers from this forum. I'm also hoping to "mine the flightline" for info. See you there!
Martin
A friend has a BUSA Pup and I refer to those plans frequently for wood sizes. I am surprised how lightly it is designed.
The original Aviatik airfoil is rather bizarre so I spent a lot of time looking for an alternative. After much consideration, I decided on a Goe 124 airfoil. It is suitably thin but still thick enough for adaquate spars - 1/4 X 3/8 bass caps with 3/8 X 3/8 balsa webbing. I found some pretty light and straight doweling at Home Depot - 3/8"dia and as light as basswood. TE will be 1/16 X 1 1/4 ply with a balsa cap.
The fuselage is rather large. The 50cc engine will be mounted on a 1/2" ply firewall, braced with 3/4" triangular stock to a 1/16" ply box that forms the forward fuselage doublers. The fuselage is made from 1/4" basswood longerons and balsa verticals and cross pieces. The forward fuselage is 1/4" balsa sheet. The whole fuselage gets covered with 1/64" ply, - acres of it. I figure I will get a little left over from two 4' X 4' sheets of it!
All struts will be GTM tubing of various sizes and 5/32" wire inserts that fit into ply mounts in the fuselage.
The engine cowling is large, and I plan on the whole thing being removeable. The radiator may stay in place or be attached to the cowling.
This weekend is Rhinebeck and a friend I are looking forward to seeing some of the models, and modellers from this forum. I'm also hoping to "mine the flightline" for info. See you there!
Martin
10-10-2010, 10:18 PM
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RE: Aviatik DI build
Wow, it's been a month since I posted the drawings' progress. I guess it won't be flying this fall.
The drawings are done enough to start building. I like to have them fairly complete before I start building. I've done models with "I'll figure it out when I get there" parts but it rarely works for me.
Here are some photos of the "core" of the model. The firewall is 1/2" Russian Baltic ply - beautiful stuff I found at Home Depot. The rest is 1/8" aircraft ply with a fuel tank floor of Liteply. The sides are the model's fuselage doublers - the 1/4" basswood/balsa side frames will be glued to the outside of these with 1/64" ply sheeting. The doublers are screwed and glued to the firewall which still has to have trianglar stock added. You can see the sidethrust built in - I kept the fuselage sides identical as otherwise I can see problems with aligning the nose. The engine is skewed to the opposite side a bit so that the prop ends up in the centre of the nose.
The wing rods will mount into brass tubing that will be attached to small bulkheads still to be added. Matching the sides on the sanding disk was so simple with a couple of short lengths of tubing as locating pins. I'm really enjoying working with these wood sizes - it's rather like building furniture! The tabs and notches took a while to cut but were actually kinda fun. I love the way everything locked together squarely. I do see the appeal of laser cutting!
Coming from electrics, I tend to weigh everything. The two doublers weighed 16.00 oz. (exactly!) before I cut out the 3 lightening holes in each. Now the pair weigh 10.15 oz. - almost 6oz. saving. What you see assembled here weighs 29oz.
Martin
The drawings are done enough to start building. I like to have them fairly complete before I start building. I've done models with "I'll figure it out when I get there" parts but it rarely works for me.
Here are some photos of the "core" of the model. The firewall is 1/2" Russian Baltic ply - beautiful stuff I found at Home Depot. The rest is 1/8" aircraft ply with a fuel tank floor of Liteply. The sides are the model's fuselage doublers - the 1/4" basswood/balsa side frames will be glued to the outside of these with 1/64" ply sheeting. The doublers are screwed and glued to the firewall which still has to have trianglar stock added. You can see the sidethrust built in - I kept the fuselage sides identical as otherwise I can see problems with aligning the nose. The engine is skewed to the opposite side a bit so that the prop ends up in the centre of the nose.
The wing rods will mount into brass tubing that will be attached to small bulkheads still to be added. Matching the sides on the sanding disk was so simple with a couple of short lengths of tubing as locating pins. I'm really enjoying working with these wood sizes - it's rather like building furniture! The tabs and notches took a while to cut but were actually kinda fun. I love the way everything locked together squarely. I do see the appeal of laser cutting!
Coming from electrics, I tend to weigh everything. The two doublers weighed 16.00 oz. (exactly!) before I cut out the 3 lightening holes in each. Now the pair weigh 10.15 oz. - almost 6oz. saving. What you see assembled here weighs 29oz.
Martin
10-11-2010, 07:11 AM
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RE: Aviatik DI build
Martin,
Have you done any weight & balance analysis to determine how much nose weight there might be needed? I'm designing a 1/8 scale electric model and I worried about the very short nose.
Also, I'm a little confused on your subject to be modeled. I'm looking at your CAD fuselage profile, and I matched it to aircraft #138.27 as your subject (page 16 of datafile 45)? Furthermore, on page 28, it's documented that 138.27 was discovered to have a "streaked" camo scheme. You mentioned that you want to use the Hexagon scheme? So, I'm confused as to what subject have you decided to model?
Jan
Have you done any weight & balance analysis to determine how much nose weight there might be needed? I'm designing a 1/8 scale electric model and I worried about the very short nose.
Also, I'm a little confused on your subject to be modeled. I'm looking at your CAD fuselage profile, and I matched it to aircraft #138.27 as your subject (page 16 of datafile 45)? Furthermore, on page 28, it's documented that 138.27 was discovered to have a "streaked" camo scheme. You mentioned that you want to use the Hexagon scheme? So, I'm confused as to what subject have you decided to model?
Jan
10-11-2010, 02:05 PM
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RE: Aviatik DI build
Hi Jan:
No, I haven't done a weights and balance analysis. Seth Hunter sent me his spreadsheet, but I found it to be rather more work when you draw by hand as I do, than it would be by CAD, (centre of areas being a major point), so I'm building just based on my experience and reference to online builds and the BUSA Pup plan. Mainly, remember to do everything I can to keep the tail light, and reconcile myself to needing nose weight.
My original drawing was fromSteve Simkin's scale drawings from the Datafile. That is 138.27, (the streaky captured aircraft that was the subject of the 1918 FLIGHT issues), and I drew the serial number on the plan. It had the earlier deep cockpit, buried guns and the rounded radiator. Subsequently, I decided to go with the relocated guns and that lead me to Oblt. Wolfan's 138.54 which is hex camoflaged, see post#5 above). I discovered in drawing this plane that the Simkin drawings, as good as they are, have some errors and I supplimented them with the JAPO drawings.
As usual, I'm probably getting more bent out of shape about little things than the intended level of scale warrants, but, hey, it's my hobby and I'll do it as I please!
Martin
No, I haven't done a weights and balance analysis. Seth Hunter sent me his spreadsheet, but I found it to be rather more work when you draw by hand as I do, than it would be by CAD, (centre of areas being a major point), so I'm building just based on my experience and reference to online builds and the BUSA Pup plan. Mainly, remember to do everything I can to keep the tail light, and reconcile myself to needing nose weight.
My original drawing was fromSteve Simkin's scale drawings from the Datafile. That is 138.27, (the streaky captured aircraft that was the subject of the 1918 FLIGHT issues), and I drew the serial number on the plan. It had the earlier deep cockpit, buried guns and the rounded radiator. Subsequently, I decided to go with the relocated guns and that lead me to Oblt. Wolfan's 138.54 which is hex camoflaged, see post#5 above). I discovered in drawing this plane that the Simkin drawings, as good as they are, have some errors and I supplimented them with the JAPO drawings.
As usual, I'm probably getting more bent out of shape about little things than the intended level of scale warrants, but, hey, it's my hobby and I'll do it as I please!
Martin
10-11-2010, 07:31 PM
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RE: Aviatik DI build
Martin,
My modeling subject will be 115.32, which is the subject in Dietz's painting on the cover of D/F 45. There's some great B&W photos of 115.32 in it, for my scale documentation.
Jan
My modeling subject will be 115.32, which is the subject in Dietz's painting on the cover of D/F 45. There's some great B&W photos of 115.32 in it, for my scale documentation.
Jan
10-11-2010, 08:04 PM
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RE: Aviatik DI build
This model tempted me but the wire wheels at this size scared me off. Certainly there is lots of history in this airframe.
Martin
Martin
10-14-2010, 10:03 PM
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RE: Aviatik DI build
Well, the sides are done and here are some photos of them clamped to the firewall/doubler assembly. It's a long thing! Remember that it will be sheeted with 1/64" ply which will add a lot of strength. I will first have to do the cockpit intereior, (as much as I am going to do), prior to the side sheeting. Right now all I want to do is get the ply on, but must resist the urge. Gluing what you see here will be done one side at a time, with epoxy, and much checking and re-checking.
Martin
(Whoops - I seem to have uploaded the same photo twice - sorry!)
Martin
(Whoops - I seem to have uploaded the same photo twice - sorry!)
10-23-2010, 11:59 AM
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RE: Aviatik DI build
A little more progress. I am staining as I go so as to avoid problems with glue later. The stain is water based and seems to glue OK. I had intended to put the cabane mounts right across the fuselage but the canister gets in the way of the front one. A pair of 1/8" ply arcs gusset the mounts to the fuselage sides and reinforce this area. I was sold on using the canister after seeing a (1/3?) scale DH4 at Rhinebeck last month. The builder had a twin cylinder 100cc engine with a pair of canisters and it sounded SO much better than the usual bark.
Martin
Martin
01-19-2011, 09:01 PM
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RE: Aviatik DI build
“I’m not dead yet!”
It has been a while since I posted on this thread, but progress continues slowly. (On the other hand, our new bathroom looks pretty good!) I find it interesting how long many ordinary tasks are taking, simply because I am inexperienced with this scale. I’ve been building scale airplanes since the early 70s, but the size of the Aviatik causes much rumination over simple structural decisions that would take seconds with a more familiar size. Probably the same thing would be happening if I was building some micro scale model.
Next step from here is probably the rear fuselage sides so that I can get the control runs finalized prior to paneling the fuselage. I’d better order cable.
There is a shot of the hinges I made. I decided not to go with mass market commercial hinges because at this scale, more accurate ones were going to be obvious, and I’d never tried this approach. I also didn’t want a design that would bind up once the control cables were snugged up. These are made with two pieces of brass tubing with a strap soldered to the outer one. This tube, with the strap is glued to the LE of the control surface during construction. The hinge was made with jigs for soldering and drilling to keep everything square. (I could have saved a week of evenings by buying GTM hinges but what fun is that!)
You can see the tail surface horn pattern I am using. The outline comes from an Aviatik drawing. The original had metal “shells over each side of the horn to give an airfoil cross section – I used basswood. Horn holes are exactly 2” apart, so the control quadrants will be the same spacing.
The tail outlines are all laminated bass. The 6 strips of 1/16 X 3/8 bass were soaked in an ammonia solution overnight before being clamped into a form and allowed to dry. Then they were glued with aliphatic resin and returned to the clamped form. This allowed a very tight radius to be held.
If anyone has opinions about material sizes or solidity of what you see, please let me know.
Martin
It has been a while since I posted on this thread, but progress continues slowly. (On the other hand, our new bathroom looks pretty good!) I find it interesting how long many ordinary tasks are taking, simply because I am inexperienced with this scale. I’ve been building scale airplanes since the early 70s, but the size of the Aviatik causes much rumination over simple structural decisions that would take seconds with a more familiar size. Probably the same thing would be happening if I was building some micro scale model.
Next step from here is probably the rear fuselage sides so that I can get the control runs finalized prior to paneling the fuselage. I’d better order cable.
There is a shot of the hinges I made. I decided not to go with mass market commercial hinges because at this scale, more accurate ones were going to be obvious, and I’d never tried this approach. I also didn’t want a design that would bind up once the control cables were snugged up. These are made with two pieces of brass tubing with a strap soldered to the outer one. This tube, with the strap is glued to the LE of the control surface during construction. The hinge was made with jigs for soldering and drilling to keep everything square. (I could have saved a week of evenings by buying GTM hinges but what fun is that!)
You can see the tail surface horn pattern I am using. The outline comes from an Aviatik drawing. The original had metal “shells over each side of the horn to give an airfoil cross section – I used basswood. Horn holes are exactly 2” apart, so the control quadrants will be the same spacing.
The tail outlines are all laminated bass. The 6 strips of 1/16 X 3/8 bass were soaked in an ammonia solution overnight before being clamped into a form and allowed to dry. Then they were glued with aliphatic resin and returned to the clamped form. This allowed a very tight radius to be held.
If anyone has opinions about material sizes or solidity of what you see, please let me know.
Martin
