Actually the plans say 3 to 4 channel, and in a post above I mentioned the dihedral depending on how many channels you want. Personally, I think that it is best to learn 4 channels because it better prepares a person for other planes. I fly 2, 3 and 4 channels myself.
I've decided to pin this message since it's the closest thing we have to an RCU endorsed trainer so far. Hopefully we'll see some construction pics and flying reports soon.
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Joined: 12/5/2003 From: Petaling Jaya, MALAYSIA Status: offline
I agree with Bruce, this plan is worth being a sticky. I feel it could be a great model for first time builders and flyers. What I'd really love to see is this thread become a construction article for the plan. As such, I think it would be great if we could start off with a bill of materials for the plane. While some woods are clearly marked, some aren't (or my eyesight is so bad I can't see the markings.) I'd appreciate a little help in this area as I've never built from plans before and I believe that the first step would be to understand the plan completely before cutting wood.
Going with the bill of materials step, I'd like to start with the wing.
RIBS - What would the ribs be made from? 1/16" medium balsa? SPARS - I see the spars are from 3/16" square sticks, but what sort of wood? Would balsa be adequate, or would they need to be made from firmer wood such as basswood? LEADING EDGE - 1/4" square balsa sticks TRAILING EDGE - 1/4" square balsa sticks AILERONS - 1/16" x 1/2" balsa strip SHEETING - 1/16" balsa sheet SHEER WEBS - I read mention of these earlier on in the thread. What would they be made from? 1/16" balsa sheet? WINGTIPS - I see no mention of how these are constructed nor what material to construct them from. A more detailed explanation of how the ends of the wings are to be constructed would be a great help here.
Well, thats it for now, I personally can't wait to get started on this build. I'm going to be realistic about it though and anticipate a slow build as I learn to interpret the plans and cut the parts as accurately as possible. Hope you guys can help me out and point me in the right direction.
>RIBS - What would the ribs be made from? 1/16" medium balsa?
Yes
>SPARS - I see the spars are from 3/16" square sticks, but what sort of wood? Would balsa be adequate?
Yes
>SHEER WEBS - I read mention of these earlier on in the thread. What would they be made from? 1/16" balsa sheet?
Yes
>WINGTIPS - I see no mention of how these are constructed nor what material to construct them from. A more detailed explanation of how the ends of the wings are to be constructed would be a great help here.
When the wing nears completion, cut the lower spar flush with the outer rib and leave the upper spar extended as shown. Cut a wingtip from 1/16" or 3/32" sheet in the general shape shown on the plan, but oversized. Place the straight portion of this tip against the bottom edge of the outer rib. The idea is to allow the end of the wingtip to be tilted upward until it comes in contact with the upper spar. You must decide how much of an angle you want the tip to be raised -- 45 degrees will work, but both tips must be the same. Your options are to bevel the bottom side of the upper spar where it contacts the tip or, if your wing is still pinned down (my recommendation), cut a notch in the wingtip to allow the upper spar extend thru the tip. Bevel the straight portion of the tip so that it fits flush with the bottom of the outer rib when the tip is correctly oriented. Once you are satisfied with the fit, then glue.
Here's why we cut a slightly oversized tip: The contour of the tip will likely not exactly match the upper shape of the ribs. Using a sanding bar (I sometimes tape the top of the wing ribs to avoid sanding them down), work it from leading edge to trailing edge removing the excess from the top of the tip. When finished, the upper portion of the wing tip will have the same contour as the airfoil. When the wing is lifted from the building board, you can then sand the remaining portion of the upper spar flush with the bottom side of the wingtip.
1/16" or 3/32" -- 1/16" can be used, but will probably need a couple of gussets to retain the shape when covering. Using 3/32" will not give much weight penalty and adds some rigidity to the tip.
The attached image would be looking from the trailing edge forward before sanding the upper portion of the tip to shape and removing the extended portion of the spar.
Hopes this helps.
< Message edited by Andrew -- 1/17/2005 4:17:06 PM >
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the "other" andrew I'm not older than dirt, but I can remember when it was patent pending
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Joined: 12/5/2003 From: Petaling Jaya, MALAYSIA Status: offline
Yes, Andrew, that was a great help. Thanks a bunch! It didn't occur to me the wingtip was at an angle. I thought the top spars were cut at an angle and went down to the wingtips.
Moving on to the fuselage now.
SIDES - 3/32" balsa sheet TOP & BOTTOM - No indication, but I'm guessing 3/32" balsa sheet as well F1 - Plywood, but what size? would Lite Ply do? If I can't source for the proper size plywood, can I use cafeenman's method of making plywood? F2 to F4 - What size sticks are these made from? LANDING GEAR MOUNT - Made from 1/16" and 3/32" plywood, but I'm not entirely sure I understand how to construct it. SERVO MOUNTS - I assume this is left up to everyone's preferred method.
As for the tail feather, they're both from 3/32" balsa I believe. What kind of hinges would be appropriate for these, as well as the ailerons?
It has just occurred to me that you may be working from the expanded thumbnail in one of Bipe Flyer's previous posts. Bipe (Andrew Donatelli) has set up a MSN Group called 1/2A All the Way and has posted full size plans of the LST 1/2A Trainer on the site. You may have to join (membership is free) to view the plans.
When the site loads, choose Documents, then Plans, then either LST-1/2A-Trainer.gif or LST-1/2A-Trainer.pdf The gif file will open with your browser. You will need Adobe Reader, free download, to open the pdf file.
All dimensions and much greater detail are available in these plan sets -- study these; I think almost all of your questions will be answered. If not, post again.
Regards,
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the "other" andrew I'm not older than dirt, but I can remember when it was patent pending
Posts: 9
Joined: 12/5/2003 From: Petaling Jaya, MALAYSIA Status: offline
Andrew,
I am using the gif file (which I had printed) from the 1/2A All the Way site, as well as referring to the PDF file from the same site. You'll have to excuse my ignorance as far as being able to understand the plans as they are, I've been brought up on a diet of ARFs and very few kits, which usually come with most of the parts cut, as well as including an construction or assembly manual. While I have learned an acceptable amount from building the kits, I'm a long way off from being able to understand what the designer intended just from looking at the plan. Some of the construction techniques employed in Mr. Donatelli's design are unfamiliar to me, especially the landing gear. I'm sure many of the more experienced builders here had no problems understanding the plans, and probably made changes to suit their own preferred construction techniques. I'm just not at that level yet
Anyways, this Friday is a public holiday here, so I'm going to start on the wings then, hopefull I'll have some decent progress and photos sometime next week.
If you want a good CAD program that is easy to learn, try Turbocad. They used to have a free version at http://www.turbocad.com , but I can't find it there anymore. The free version I have is 5.1 from 1998, but you can get version 8 for around $10 on eBay.
If you type free turbocad into google, you can find plenty of mirrors of the free learning edition still up. This link will get you to one of them. http://www.al-ki.com/tcad/download.php#TurboCADLE
Where did you get the 1/2A Library from? Any others? Inquiring minds want to download
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Joined: 4/28/2003 From: Brunswick,
GA, USA Status: offline
Here's a Bill-of-materials that I made up. Bipe- How about adding a gear detail? I can't tell what your intentions were. How is the dihedral attained. The wing is shown as one piece. If it's a trainer then newbies will be building it.
Wings Ribs - 3/32 Balsa Sheet 3"x36" (1) Spars - 3/16 Square Balsa 40" long (2) TE Sheeting - 1/16 Balsa Sheet 1/2"x37" (2) Sheeting - 1/16 Balsa Sheet 16" long (1) Leading Edge - 1/4 Square Balsa 40" (1) Trailing Edge - 1/4 Square Balsa 40" (1) Aileron - 3/16x3/4 Trailing Edge 37" total (1) Shear Webs not shown but could be added using 1/16 sheet on the front and back of spars with vertical grain
Fuselage Sides 3/32 Balsa Sheet 4"x26" (2) F1 - 1/8 Plywood F2 - 3/32 Balsa Sheet in 5/16 and 3/8 widths F3 - 3/32 Balsa Sheet in 5/16 and 3/8 widths F4 - 3/32 Balsa Sheet in 5/16 and 3/8 widths (F2-F4 can be made from scraps) Landing Gear is 1/16 ply 5/8 wide and 5/16 tall Tail Feathers - 3/32x4x36 Balsa Sheet Gear wire is approx 3/32
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Joined: 12/11/2003 From: Ottawa,
ON, CANADA Status: offline
I don't know if anyone else knows this already or not but the Sig Kadet has already been previously scaled down for 1/2A use and was published as a construction article in M.A.N(Nov-94).The name of the plane was "Kadetito" and it used a .074 engine for power.Wingspan was 39" and the length was 31".It is plan number FSP11941 if anyone is interested.Here is some site info on this particular plane.Very similiar planes indeed.
I haven't been getting updates on this thread since it stickied, so I only just read the last bunch of suggestions. I'll make the changes to the plan and re-upload it.
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All Forums >> RC Airplanes >> "1/2 A" & "1/8 A" airplanes >> RE: 1/2A trainer anyone? 
RE: 1/2A trainer anyone? - 
RE: 1/2A trainer anyone? - 
