More from the Lift Indicator Project, ( Aug 22nd, 2001)
I got the aluminum hershey bar for the lift indicator probe lately:
If you weigh it in your hands, then it's a lot of weight just for holding two 6 inches long holes 1/2" apart. As Burt Rutan said: if you throw it in the air and it falls back to the ground, then it's too heavy (for the Voyager).
I don't build a Voyager clone, but I got a similar feeling.
Another problem is a manufacturing one.
If your drill presse's table is not ~exactly~ perpendicular to the drill spindle then these long holes may, instead of going straight down, exit somewhere at the side (or meet somewhere inside). I didn't even gave it a try.
So there are two requirements to fulfill:
I'll make it from ... tatatata... excess Plexiglass sheets. I found an abandoned piece of 4.6mm thick Plexi. The complete probe will be sandwiched using three parts:
The three pieces will be glued together with Plexi glue. The glue dries very fast and seals everything airtight. I think it will make no difference for the probe that the air channels are square now. The tube adaptors can be made of two small Plexi tubes glued into the block. The two small air inlet holes I'll drill when the sandwich is cured. Another advantage: I can even see bugs sitting in my lift indicator probe at the preflight check.
Comments always wellcome
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Aileron Tip Ribs, ( Aug 13th, 2001)
The flaps went so well together last weekend, so today I was looking for a (still) more challenging task.
This is the one. Aileron tip rib (SNX W04-10R/L). This is one of the most difficult looking detail plans. So fresh to work. First Task was fabricating two particle-board formblocks (right and left one).
The long side of the triangle will receive a 135 deg. bend. So I set up my bandsaw to 45 deg (lucky one if your bandsaw got such an feature). The cut was so clean that no rework was required. Then a 1.6mm radius was applied to all three edges. This was easy.
Instead of hammering the sheet around the formblock (which would lead to a banana-shaped part for sure) I used my proven 'combined formblock-bending-brake method'.
The brake bent the sheet nicely and tight about 130 degrees around the formblock. For the remaining 5 or so degrees I will use my seaming pliars.
This is the part so far (left one). It's nicley true and straight. Ovarall working time was about 4 hours. Next step is cleaning, etching, alodining and priming the inside and polishing the outside.
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Flaps, ( Aug 12th, 2001)
This weekend I made the flaps. The ribs I had already fabricated (they fitted perfectly), the prebent skin came from Sonex. This was a good deal. The bending is very good and the size is exact to 1/10mm. I would never be able to get the same result at a local sheet metal shop.
What puzzled me wih this part is drawing W05-01/top. It's a view onto the leading edge of the flap
This is one of the few drawings which caused more confusion to me than enlighment. At the first (and second and third...) glance one would assume that the inboard end is slanted in a strange way by about 45 degrees. THIS IS NOT THE CASE! I looked and looked at this drawing, but couldn't figure out what's actually shown here. So I had a look at Dave Koelzer's and other's webpages. The pictures there showed the part so as I expected it to be.
I took all my will and started cutting, curious what would come out.
This is the part as it should be ( I think). I tried to take the pic using the same view as the drawing. Maybe you can catch the idea. The red arrow thows this ominous line. So if you make this part, just forget the drawing and just make it to the dimensions. It (most probably) will come out O.K.
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I made a $40 Rivet/Dimple Squeezer, ( Aug 6th, 2001)
A look at Avery's and Wick's catalog told me about $150 upwards for a hand-rivet squeezer (shocking). Readers of this saga may remember that I prefer to dimple and flush-rivet wherever possible. So I need such a tool for dimpling the t'deck formers and later the wingribs. Question was how to avoid the heavy attack on my (already leightweight) wallet.
Pliers with parallel jaws (1) will do the trick. So I acquired one at the company, spend 10 minuts of drilling (be careful when drilling chrom vanadium steel - low RPM and lots of cutting oil). Viola:
Here's the tool. It works O.K except a small inconvenience: I have to open the jaws to insert the skin, then press, then close the jaws further and then final press. The jaws do not move wide enough to work in a single step. But this is acceptable. For moving the jaws you just push the button (2) and move the lower jaw into the desired direction. So I saved about $150, or 10 boxes of beer , or 50 bottels of Italien red wine or....
The second time now I test-fitted the t'deck skin. However this time only the rear-part of the laterally split skin. The formers attach nicely to the skin. Small gaps can easily be 'adjusted' by hitting lightly on the flutes from the downside.
...what if I put side-windows at the openings and a third jumpseat inside?! - if only this stupid CG wouldn't be in the way...
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Turtledeck Saga Continued, ( Aug 3rd, 2001)
Today I try-fitted the new (second) turtledeck splice channel.This worked out nicely here:
and also the transitions between spliceplate and bulkheads #3 and #4 couldn't be better. HOWEVER bulkhed #2 was totally out of shape. I couldn't make #2 fit even with slight pushing and pulling. I have no explanation for this. The splice channel is straight and the bulkhead is final riveted and so couldn't have changed.
Looks as if there is no cure for this problem. This means a completely new bulkhead #2 (and another 10 hours of work). Luckily I only clecoed the bulkhead assembly to the sidewalls....
Maybe I can use this one to make a doghouse? Or do some destructive testing? I read in ANN today from a guy who hit his experimental to pieces with an axe after an emergency landing. I'm not far away to do the same...