Cutting the Sparcaps (Oct. 28th, 2001)

I was the happy Sonex customer to receive the last 'raw' sparcaps from Sonex-Ltd. (I purposely wanted the raw ones. So what I received was a returned order from another customer who exchanged the caps for the machined ones. From rough handling the material was badly scratched all over [even tho I had to pay the full price]) . All following shipments are the ready-machined sparcaps which look very nice because of the anodized surface (However from the RV mailing list I learned that anodizing will reduces the material's fatique strength by 50%. On the other hand it's said that even then the strength is well above the savety margin... So I'm more comfortable with my own way of corrosion protection alodining and epoxy-priming.

Initially I intended to give the parts to a local machine shop, but later I realized that this 4 meter monsters were simply too large to clamp on the lathe. So I have the fun now to grind down the aluminum using my homebuilder equipment.

This is the way I mounted the bandsaw flush to the table surface. Actually cutting was easier than expected. One blade held up for all four sparcaps. I tried to cut 2mm to the line. The remaining 2mm I will grind off using my new router (this was a cheap special offer).

Will see how it works.

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What happened since the last Update. (Oct. 21th, 2001)

(A) I (almost) finished the rudder. There's no pic because I polished it mirror-like and so it is invisible on the photos. The parts need priming and riveting. The parts are stored away temporarily until I find a place to spray the primer. Outside it became too cold now for painting. My aim to solid flush rivet wherever possible becomes questionable for the Sonex control surfaces. This 'envelope' type of construction prevents the use of a bucking bar. Seems as if I have to use flush blind rivets. When I recall all the problems reported at the email list with protruding rivet stems this may be not much fun.

(B) The engine stand is finished

The remaining openings have to be closed then the dirty oil sardine goes to steam-cleaning.

The arrow shows the locking mechanism. I can turn the engine to any 90 degrees.

(C) The vertical tail forward spar is assembled. The 35 degree bend at the solid attach plate is real muscle work. I used a 2lb hammer and bent the plate over my radiused aluminum block. I always put a piece of hardwood between the alum and the hammer. I hammered a bit, measured angle, hammered, measured ... It was tiring but worked better as expected, no cracks, no dents.

Also this sub-assembly waits for priming and riveting.

(D) The lift indicater probe is ready (select the topic at left scroll bar).

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I'll build an Engine Stand. (Oct. 4th, 2001)

No, not an engine teststand. Just a fixture which allows to turn the engine 360 degrees around.

these are the parts. Rough steel work.

When the engine is attached I'll cover all openings

These are the covers for exhaust and intake openings.

After this the engine goes to the high-pressure steam cleaning.