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Cowling "Puter Oner" For My Rocket

HFS

Well Known Member
After 20 years of putting the lower cowling on my Rocket by myself, I have finally gotten to the age of not being sure I could do it any more without the possibility of doing some unrecoverable damage - hence the need for a "Puter Oner".

I've been thinking about it for a while, and thought I had a pretty good working "idea" to start from.

Below is what came out of the shop - the bare frame looks like a simulator for roping Texas longhorns!

The other two pics show the cowling positioned under the motor - in a horizontal position; and, then with the "scissor" lift advanced - the rear of the cowl sits on the top of the gearleg fairings, which act as a support at that point, making the rotation up & under the spinner much easier physically.

The scissoring aspect is advanced either by a manual crank handle, for precise placement, or by cordless drill for a faster advance. Either way works - their use just depends on the need for speed or precision.

There is a manual "foot" brake at the front of the frame to give a bit of stability after the initial placement under the motor - otherwise, with 4 casters it's like skating on ice. I elected not to use brakes on the casters because I didn't know if I'd be able to access them at the critical time of placement. Where the foot "pad" is now, I can just reach down to set it.

YMMV - HFS
 

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Elegant mechanism! Well done.

I made a crude Rube Goldberg holder for (-7) my floor jack but it is not easily adjusted vertically. I need a better method.

Question, so, you pivot the cowl about the lower aft edge near the FW? And it will pass the aft side of the spinner?

I would love to do that to clear the protruding gear fairings. Honestly, never tried it cuz did not think it would fit.

Also, would an Acme 1/2 10 TPI work better for the jack?
 
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Beauty

That looks really good, a clever design and fabricated very nicely. Now, what color are you going to paint her (too beautiful to be "it"!)? ;)
 
Very, very cool - much nicer than my long-time method of supporting the cowling on a knee with that foot off the floor, while standing one-legged on the other foot!

Will have to consider this as the calendar advances……
 
Very nice. I use a crude arrangement of a piece of foam rubber sitting on top of an oil case, which rests on a plastic toolbox. It works, but...yeah.
 
I made this contraption. I made clips that hook into the side piano hinges and used Dacron fishing line to wrap around the inside PVC pipe to real up the line and raise the cowel. Also incorporated thumb screws to lock down the PVC pipe so it would stay up after raising the cowel. It works pretty swell…

Darn picture is upside down… how do I fix that?
1F649FB2-6C00-4673-8EEC-BBA07CD171E5.jpg
 
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Wow, that's brilliant! I've been thinking that I need to upgrade my super-bush-league solution to something less sketch .. I'm going to steal some good ideas from yours!


IMG_0350-M.jpg
 
Picture downside up ...

Steve,

If you open your image with a GNU image manipulation program (GIMP), rotate and save the file without the XMP and Exif data (that tells the file how to orient among other things) you'll get what you save... no upside down photo.

It's easier to do than explain, after you do it once it's easy!

Go to https://www.gimp.org/ for an open source download. Free
 
A big part of the problem with my Rocket cowl is that it is "scratch" built, to accommodate a Dave Anders designed plenum - so it's heavier than John's standard cowling; and, since it's for the IO540 - it's heavier still. At my age (70+), trying to "wrassle" it into place, without scratching/damaging it is daunting.

Also, like other RV's with round gear, you have to angle the cowling up at the back to "land" on top of the gear leg fairings, and then rotate upward at the front to slip behind the spinner - which sometimes takes a bit of muscle & finesse - both at the same time. It really helps to have the cowl stabilized during this process, in case "adjustments" are needed. So, any mechanism I came up with had to have some sort of rotational aspect to its operation - I can't just go straight up with it.

As to the colors - Battleship Gray for the frame, and Safety Red for the scissor links and handle. Haven't decided about the Pool Noodle - I'd like to paint it, but am afraid some of the paint might rub off and scuff the cowl during the install. So it will end up white for now.

HFS

I like the PVC idea - but I still have to get my great big cowling in the right spot to be raised, and then it needs to be done at an angle - and then slid back a bit to engage the GL fairings. I don't have the luxury of going straight up from the get-go.
 
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Simple but it works
 

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very nice!

Did you scratch build the scissor/jackscrew assembly and threaded rod, or did you salvage these items from something else? I ask because i want to copy!
 
Here is my cowl trolley for an "A" model, made from a device that Harbor Freight used to carry, as an motor stand. Had to get around the nosewheel.
It doesn't lift the cowl, but it could probably be made from PVC pipe.

Bottom Cowl Tip: Temporarily tape back/up the rubber on the front of the lower cowl with blue painters tape until it is lifted above the front ramps of the engine. Makes getting the cowl behind the spinner a little bit easier.
 

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blue flyer - scissor/jackscrew assembly

Part of the overall design and all scratch built to the specs.

The hardest part really was to make the steer "horns" fit the cowling well enough to feel comfortable about using them for support.

HFS
 
Ron RV8, I like that idea a lot. I could even build a trolley to let the cowl down on to keep it off the floor, and keep the lifting device on the trolley while not in use.
 
All Painted Up and Ready To Go To Work!
 

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