Steps to scratch build a VW

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Little Scrapper

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I just finished reading this whole thread. Good read!

I do have two questions though....

Pops....what is an SSSC? I assume one you designed and built yourself?

And Little Scrapper....what is/was you conclusion about engine size, and are you still doing the V-Witt?
I switched to a Baby Ace and that airplane is going well. Look in the projects section under “Pomodoro”.

After this thread I concluded that I’m very fond of the VW and would love to fly behind one eventually and I do plan on finishing the V-Witt.

I think this thread is my favorite thread on HBA because I went out and did street work by visiting shops and talking to knowledgeable people and separating fact from fiction. I put a lot of real work in to this thread instead of being a keyboard warrior.

When I started this thread a small part of me almost expected the VW to fail. Perhaps internal fear on my part? Personality glitch on my part!? I’m pretty hard wired to like Lycoming or Continental which seems like a natural bias.

But the opposite happened. The more I researched the more I ended up learning about VW and the more I learned the more I liked it. I think it’s a great choice for the right sized pilot in the right sized airplane and I think of a person can be honest with himself about his wants and desires it becomes clear that the engine fits certain people in a certain mission. It’s kinda like stretching a glide, pretty dam hard, haha and a VW won’t “stretch” well either. Probably a bad analogy but you get the point.

A nice VW built to last by keeping performance goals limited can give a owner very long service. My opinion only.
 

Pops

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The SSSC is built like a Fisher Super Koala, but to the dimensions of the Fisher Koala 202 for the Cub look. Not one part is the same as either airplane. Landing gear, engine mount all hardware, control system, etc,etc, is my design. Its stressed higher than the Super Koala. The prototype Super Koala is in a hanger next door and I bought a wrecked Koala 202 for the plans to get the general dimensions. Wish I had called it something else than what I put on the FAA paper work. The then owner of Fisher said he was thinking of doing the same thing for a kit, but sold the company shortly afterward. Then in describing the performance, I said its like a Single Seat Super Cub , so the name SSSC stuck.
Powered by a 1835 cc, 60 HP, VW with a Culver 60"x 26" pitch prop. Cruise at 80 mph at 2600/2700 rpm with a 1200+ ROC. 2--- 8 gal wing tanks for a total of 16 gal @ 3 gph @ cruise.
 

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jeffwalin

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The SSSC is built like a Fisher Super Koala, but to the dimensions of the Fisher Koala 202 for the Cub look. Not one part is the same as either airplane. Landing gear, engine mount all hardware, control system, etc,etc, is my design. Its stressed higher than the Super Koala. The prototype Super Koala is in a hanger next door and I bought a wrecked Koala 202 for the plans to get the general dimensions. Wish I had called it something else than what I put on the FAA paper work. The then owner of Fisher said he was thinking of doing the same thing for a kit, but sold the company shortly afterward. Then in describing the performance, I said its like a Single Seat Super Cub , so the name SSSC stuck.
Powered by a 1835 cc, 60 HP, VW with a Culver 60"x 26" pitch prop. Cruise at 80 mph at 2600/2700 rpm with a 1200+ ROC. 2--- 8 gal wing tanks for a total of 16 gal @ 3 gph @ cruise.
That's a nice plane, Pops! I really like the VW powered mini-cub idea. Always liked the Preceptor stuff until it disappeared.

I plan to build a bare bones minimalist Cygnet SF2a with some kind of VW power, likely an 1835. I waffle about going bigger for the extra oomf if needed, but don't want to sacrifice reliability.

Jeff
 

Map

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The magneto is positioned by the Diehl accessory case. I assume it lines it up centered. The wear was in the interface of the tabs of the mag drive to slots in the drive puck. I had a Limbach engine for a while with a magneto and it showed similar wear in that location although it was steel on steel. Those torque pulses are just hard on it.
I added a spacer to the pinion drive gear installation to keep it in place.
 

Hot Wings

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I assume it lines it up centered.
The wear observed sounds just like the wear you will notice on the oil pump drive tab. One would assume that the oil pump shaft axis and the cam axis would be collinear, but they very rarely end up that way even when using the proper tool to center the pump during assembly. It is just something we live with when building VW engines........and one of the reasons we use oil filters.

A check with a dial indicator during assembly of the accessory case, I would guess based on prior experience, will show the true reason for the wear.
 

Pops

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I don't use the Diehl accessory case because I don't want all the added weight for a electrical system. I use the small mag mount from GP's. You have to drill and tap for 4 bolts that bolts the mount to the rear of the case. Even though it has a step to locate it on the rear of the case there is a few thousands slop in the fit. You have to do a lot of measuring before locating and drilling the case for the bolts.
So far with several hundred hours there is no wear in the puck.
Don't assume anything. The VW case is cast and machined with a certain amount of tolerance and same for the Diehl accessory case.
 

Map

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Pops, do you know a source for the wire style circlips (used for securing wrist pins in pistons)? I lost one. The new ones are different, I could not find the old style anymore other than with the complete set of cylinders and pistons.
 

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Grumpy Cynic
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Any local VW shop should be able to find a used one in the iron barrel. Just make sure it isn't worn on one side from rubbing on the pin. This style of clip also tends to raise a ridge on the piston pin bore making pin removal a small problem.

Maybe a better option would be to just swap them all out for retaining buttons?

Depending on the shape of the grove in the pistons the "C" clips - might - be an option. They tend to pop out if installed with the sharp side in when used with a grove with too much radius.
 

Pops

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Pops, do you know a source for the wire style circlips (used for securing wrist pins in pistons)? I lost one. The new ones are different, I could not find the old style anymore other than with the complete set of cylinders and pistons.
Yes , email sent
 
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