Glider Maintenance - Fuselage Rotisserie

On Friday, January 6, 2017 at 1:09:13 PM UTC-8, Papa3 wrote:
Yeah, I had seen this. Still salivating: https://vimeo.com/60497114

P3, I dug this up from the archives. Link below.

A photo scanned from the August 23rd 1991 "Hollywood Reporter" article on soaring, "The Quiet Ride".
It shows an ASW20 - without the taily bit - in the rotisserie at Glass Teck Unlimited. And Rick Wagner with arms folded. Nostalgia for R12 folks.

Also visible is Rick's model of "Rare Bear", of course its analog R/C failed impressively at high speed!

Bonus: If you look in the folder with a familiar name, there may be soaring cartoons for winter reading.
Jim

https://www.dropbox.com/sh/0gh8y9b7p...ykXOTBjEa?dl=0

On Friday, January 6, 2017 at 3:49:28 PM UTC-5, Bob Kuykendall wrote:
In my shop, we have two rollover rings:

* An octagon made from two plies of hardware-store 2x4s, where the plies overlap at the joints. I also made a roller stand for it, but we mostly just set one of the eight edges down on the floor.

* An infinigon (my daughter's term) we made out of a 48" diameter welded steel hoop salvaged from an abandoned kid-sized trampoline. We use it with the roller stand I originally made for the octagon.

In both cases the hoop attaches to the forward lift pin fitting, which by definition can carry several times the non-lifting weight in pretty much any direction. There is also a strut that attaches the hoop to one of the two aft lift pins to prevent the hoop from rotating around the axis of the forward lift pin fittings.

For the aft fuselage we generally just rest the tailboom on a padded sawhorse just forward of the vertical fin. We also have a sawhorse with two rubber wheels for this duty as well. For a finished glider, we girth the tailboom with masking tape where the roller runs so it doesn't scuff the paint.

There are photos in the HP-24 facebook page albums, probably back around October 2015 when we were painting 24-03.

Thanks, Bob K.
https://www.facebook.com/HP-24-Sailp...-200931354951/

The nice thing about the octo version is that it takes up very little space when it is not being used. If you are in a big shop and move stuff around a lot, a roller stand is a nice addition. Most of us find that space is the most valuable resource in the shop and storing big stuff you don't use very often is not a good use of that space.
I use a simple stand with a curved upper face that nests the fuselage. The curved upper face is 2 pieces of 2 inch pink foam mounted vertically in a box on the top of the stand. If I need a special contour is is cheap to make from the foam and the foam does not scratch stuff. It allows me to rotate about 120 degrees either side of vertical which allows access to almost everything I need to do. I can position without help. With that and an electric hoist I can do everything I need to do without needing help.
P3 is familiar with my cheap ass solution.
FWIW
UH

If you ever wonder why quality sailplane repairs are so expensive just have a look at that vimeo piece. I wonder how many hours that took. Mike Robison at Ridge Soaring has something like what you are talking about. Maybe you could get some pics of his? BTW, I saw a repair he did (in various stages) on a Nimbus(?) just like that video. When finished, you couldn't tell it from new. I'm always amazed by the skills of those of you who do that kind of work.

Hank,
How do you attach the fuselage to your hoist? With a rope through the spar hole, then to the lift fitting on the other side?
JJ

Yes, usually using either a sling or rope. Simple lifts are sometimes a rope loop (laid flat, so 2 runs of rope in the middle and loops on each end) that pick up the fuselage pins. The loops on the ends are on the fuse pins, the middle goes in the hoist hook.

For Schweitzer ships, we have a large stand (similar to a horse) with a hole in it parallel to the ground that picks up the glider front grab handle (2-33) or an adapter attached to the front bulkhead (nosecone removed, 1-26, 1-34, etc) so the fuselage can rotate on the front end and the tail boom on a smaller stand.

On Friday, January 6, 2017 at 6:48:47 AM UTC-7, Papa3 wrote:
After years of wandering around northern NJ temporarily occupying the workshops and garages of club members who were kind (or stupid) enough to loan out space, Aero Club Albatross (ACA) finally has a shop of our own at Blairstown airport. As the Refinisher in Chief, I'm building out the infrastructure bit by bit to make sure we are well equipped for future projects. I'm looking for good examples of fuselage fixtures, especially ones that allow for the whole fuselage to be rotated at least 90 degrees either way from vertical.

So, does anyone have examples of a fuselage rotisserie with some photos you can share? We already have a cradle/sling as well as solid stands. We also have used a hoist from the ceiling in the past. Each of these presents some challenges when painting, so we're looking to start fresh. Any pics, sketches, or ideas would be appreciated. We have world class fabricators and machinists in our club, so we can go top tier - no 2x4s and bungee cords. You can email me at erik dot h dot mann @ gmail dot com

Erik Mann (P3)

Jonker Sailplanes has a pretty slick flippable jig that feeds thru the wing pin bushings allowing the fuselage to rotate 360 degrees. If you are or know a decent fabricator, you could probably make one. Photo depicted on their Facebook page for the JS3.

https://www.facebook.com/jonkersailp...type=3&theater

Thanks all. In addition to the posts here, I got several private emails. Man, we have a lot of talented fabricators and engineers in our midst!

To summarize, it looks like there are 3 major designs:

- Steel (or plywood) hoops with an integrated cradle on casters. These have the advantage of infinite degrees of rotation. Potential cons are that there's a lot of "stuff" to store if you have a smaller shop (like we do). Also, the structure makes spraying challenging as there are a lot of impediments around the mid-section.
- A wood octo-hoop made from plywood which by definition has 8 predefined "stops". Similar to the first one but can be free standing.
- The hanging rig with a hoist and spreaders.

We've previously used a hoist and associated sawhorses to good effect. Looking back, I think if we'd spent a little more time on the rigging itself (including maybe a square-off spreader arrangement to give a bit more room to maneuver the spray gun) we might have been happier with that setup.

Anyway, thanks to the dozen or more folks who replied. I'll post the results of the final product when/if we get to it.

In the meantime, progress reports from the current club project (Grob Twin Astir fuselage refinish) are he https://www.facebook.com/aeroclubalbatross/

P3

On Friday, January 6, 2017 at 7:48:47 AM UTC-6, Papa3 wrote:
After years of wandering around northern NJ temporarily occupying the workshops and garages of club members who were kind (or stupid) enough to loan out space, Aero Club Albatross (ACA) finally has a shop of our own at Blairstown airport. As the Refinisher in Chief, I'm building out the infrastructure bit by bit to make sure we are well equipped for future projects. I'm looking for good examples of fuselage fixtures, especially ones that allow for the whole fuselage to be rotated at least 90 degrees either way from vertical.

So, does anyone have examples of a fuselage rotisserie with some photos you can share? We already have a cradle/sling as well as solid stands. We also have used a hoist from the ceiling in the past. Each of these presents some challenges when painting, so we're looking to start fresh. Any pics, sketches, or ideas would be appreciated. We have world class fabricators and machinists in our club, so we can go top tier - no 2x4s and bungee cords. You can email me at erik dot h dot mann @ gmail dot com

Erik Mann (P3)

I have both wood and steel rings in my shop. I had the steel tube rings rolled and my son and I cut and welded them together and added four tangs to mount whatever was needed. I have a Ka-6 and an Lo-150 in those right now. But before that, I needed a way to handle a Ka-2b two-place fuselage. So I built a ring from a single sheet of 4'x4'x3/4" plywood. I can send you a diagram if you are interested. My wood ring is currently holding up the front of an ASK-14 fuselage project. nealpfeiffer at sbcglobal dot net

On Saturday, 7 January 2017 17:14:48 UTC+2, wrote:
If you ever wonder why quality sailplane repairs are so expensive just have a look at that vimeo piece. I wonder how many hours that took.

That's exactly what went through my mind about 5 minutes into the video clip.
The payroll for all those skilled artisans must be at least 90% of the cost of doing business. It's a wonder that these composite repair companies actually stay in business.

On Sunday, January 8, 2017 at 8:40:37 AM UTC-5, wrote:
Hank,
How do you attach the fuselage to your hoist? With a rope through the spar hole, then to the lift fitting on the other side?
JJ

Several ways depending on ship and what I'm doing.
I use either rope or 1 inch strap.
1- Loop under lift pins on ships like Schleichers- safety on pin end so strap stays on.
2- Same for SH type ships but insert a 1/2 inch bolt about 5 inches long into front bushing holes.
3- Strap looped through shoulder harness straps.
4 Just loop around the bottom- Less stable and more likely to slip in rotation or fore and aft.
NEVER through the obvious spar holes unless planning to repair.
Once main is up tail goes on support padded with old water bed edge parts.

The lower the hanging point, the easier rotation is when spraying.
UH