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May 19, 2019, 07:12 PM
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Jay,

I've looked at the plans and done my best to translate the German, but it doesn't spec how the tips should be built. I'm just going to steam bend and laminate layers of bass to get to the 1/4' x 5/16" cross section . So let's say five 1/16" strips around a form using titebond between layers.

My clothes steamer - conveniently located in my workshop - has extensions that form a long straight handle for doing curtains, etc. It is perfect for putting up to 48" stock straight down the pipe. I don't cap the end, but it still does that job just fine.
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May 20, 2019, 08:52 AM
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I have a question for the collective. I want to fabricate my own brackets and fittings for this aircraft and would like advice on what thickness and type of metal to go with . Although I believe different types of material could be used depending on the purpose, (steel, aluminum and brass), it might be just as easy to stick with one material for ease of sourcing and working with it.

Here is a sampling of the parts that I will be fabricating. Keep in mind this is 1/4 scale and some of these parts will be critical in terms of strength.

Thoughts?
May 20, 2019, 06:54 PM
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Using the tried and true Pat Tritle method of forming wing tips, I’ve cranked out of a couple in a matter of a couple of minutes. As a test I decided to go with medium straight grained balsa instead of basswood thinking that the laminating process will harden up the assembly rather than a single piece of steam bent balsa. I’m pretty happy with the result. It’s very stiff and very lightweight, so I may go with it for now. I still have time to change my mind.

1) steam the wood to loosen it up
2) shape it over the foamboard form
3) add a very thin layer of Titebond between each of the 4 strips of balsa
4) tape it to the form very tight so no gaps exist
5) nuke it in the microwave for 20 seconds. Let cool.
6) out pops a perfectly formed piece.
May 22, 2019, 08:04 PM
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Tonight I made the last two ribs which were not the ordinary size and shape. These are the same length but are thinner in profile with the same basic airfoil curve.

So I dug out the old rib form and decided to use the bottom of the rib profile, but I created a spacer out of 1/8Ē thick foam to fill in the gap at the top. I used the profile of one of the ribs as a template and cut the foam to shape. It worked like a charm. I still need to add the ply to the joints, but Iím pretty happy with the result.
May 29, 2019, 08:34 PM
SAM Elec GrdChmp04,07,10,12,14
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Here is some progress made on building the Fillon Champion.
I am learning that making the elliptical dihedral curve in the wing takes a lot of technique that I haven't learned yet. Even making the wing tips has been a learning curve.
I just never had to bend balsa and spruce so much in my past builds.
As I try and workout the wing, I've been building the fuselage and adapting it to electric power.
Also decided to set it up with a flying stab (Stabilator) to minimize problem with wing incidence. The plans as they come are for free flight
and most free flights have more positive angle of attack than is needed when flying it as RC.
Last edited by Jay Burkart; May 29, 2019 at 08:42 PM.
May 31, 2019, 09:45 AM
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Looks really good Jay! I need to come out and check it out in person, but I also need to borrow your table saw.

My progress has been incremental, but not worthy of updates for the whole 2 people watching this build thread. LOL Both wings are fully glued up and the leading edge strips have been attached.
Jun 10, 2019, 06:32 AM
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Making some additional progress. Now that I have the wings framed up, I have been doing the same thing to both wings one after the other. That way I donít get too far ahead of myself and forget how I did something on the first wing.

SPar caps are installed; wing tips installed and reinforced, and the first bent ply leading edge is finished, That one was a first for me and it turned out great.
Jun 10, 2019, 04:41 PM
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Take Heart!


Dion,

I'm glad to see that you have resumed the build. Take heart, there may be more than two others watching your posts. But not everyone responds.
To address the hardware issue, let me admit that it will be a lot of hard work. My 40% Sitzgleiter did not have nearly so many parts to fabricate. This is one of the reasons that I have not gone on to construct a model of the Hols. My advice is to find a machinist to fabricate all of the necessary hardware. If one were building a 100% scale replica, this is what one would do. But you probably want to do it all yourself anyway.

I made most of my hardware from 304 stainless steel. I used stock from K&S or Small Parts. I wore out several blades in my tiny 4" table saw. At your 1/4 scale, many of the parts could be roughed out with metal scissors or a small shear. I have no break, so I just clamped parts between metal blocks to do the bending. It took lots of jigs to do everything. I am experienced in hard soldering and used those skills wherever necessary. I bought parts from Small Parts such as pulleys and thimbals for metal wire. Small Parts is now part of Amazon and I'm not sure they still make all the items they did before the acquisition. Proctor also has many hardware items at 1/4 scale.

I looked over my Drawing No. 4 of the hardware. Only three thicknesses are called out; at 1/4 scale these are: .020", .015", and .010". You could safely make everything from just 0.018" stock (#26 ga.), which is easily obtainable.
Keep at it!

jim
Jun 11, 2019, 06:47 AM
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Jim, thanks for the response and I’m glad you are back on board! I’ve been pouring through your pics reviewing all aspects of your build including the hardware. I’ve decided that this build will receive a combination of form and function. ie: not every part will be exactly scale but will be functional and resemble scale enough to satisfy anyone looking at it!

An example of that might be in the strut attachments at the wing spars. They will look the part, but won't be double reinforced at the base like the original drawings. Honestly, my biggest head scratcher right now is how I am going to fabricate the aileron hinges.
Last edited by dion9146; Jun 11, 2019 at 10:21 AM.
Jun 16, 2019, 05:40 PM
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Managed to get the top and bottom of the wing tip ply installed this morning before heading off to the sailing club, along with the root rib covering. Now lots of ply reinforcements need to be cut and installed throughout the wing before tackling the ailerons.


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