Shock absorbers for 80% replica AVIA B-534

[Svetlio_i]

Hi everyone ,
I'm looking for someone who can build Hydro-Pneumatic Shock Absorbers for 80% replica AVIA B-534. Can someone help me with this task :



I have done a little sketch how this need to look


Did someone know where I can get them made ?
Thanks

 

[Vigilant1]

Will they be visible and do you need the struts to look and function just like the originals?
From the pictures, it looks like the AVIA B-534 oleo strut was covered by a streamlined fairing. That would let you put just about anything inside and maintain the right look with the fairing in place.

 

[Svetlio_i]

yes , the original are oleo strut cover with fearing. The thing is I'm trying to build maximum close to original . I was looking everywhere for somebody to build it. My last resort is the other option.

 

[Vigilant1]

Thanks. Sorry, I sure couldn't build you one. In your place I'd probably try to fabricate something that looked correct on the outside (with proper telescoping motion) and hide a functioning off-the-shelf oleo strut from a motorcycle etc inside that.
Apologies for the lack of specific assistance. Are the dimensions you posted for the full-scale strut or for your desired 80% strut?

P. S. That's a good looking biplane.

Mark

 

[delta]

Perhaps an off the shelf item could be adapted. Bilstein Front Shock Absorber fits Rolls-Royce Camargue 1975-1987 | eBay

 

[Svetlio_i]

Thanks Mark. The pointed dimensions are for 80% replica. I have another option but I don't know will it work. To get struts from IVECO STRALIS and modified them for my needs, but this is one of the options . I would like to make proper ones
Svetoslav

 

[Svetlio_i]

Perhaps an off the shelf item could be adapted. Bilstein Front Shock Absorber fits Rolls-Royce Camargue 1975-1987 | eBay

Thanks Man, but the struts need to be inverted as per original

 

[wsimpso1]

If they really must look like those, you will most likely need to research the seal sizes suitable to your shock fluid, then do the detail design of the parts using enough preload on the seals to make them work and within the pneumatic pressures the FBO's can service. Then you would have to run through the orifice sizing to make the oleo part dampen fairly well. You will want to make this accessable so you can adjust the damping.

Pazmany's Landing Gear Design for Light Aircraft, Volume 1 covers the landing loads, travel, etc. He showed a couple designs but did not provide details, nor did Volume 1 cover how to design the pieces nor how to design the damping. Unfortunately, we lost him before he wrote Volume 2. Volume 1 is kind of pricey but I bet it can be borrowed through an interlibrary loan.

The alternative is you may be able to search up a house that designs and builds pneumatic and hydraulic machinery, and they would just take your required force and travel profile , then design and build for you. You still gotta know what to ask for in terms of strut force vs travel, etc.

Billski

 

[Svetlio_i]

If they really must look like those, you will most likely need to research the seal sizes suitable to your shock fluid, then do the detail design of the parts using enough preload on the seals to make them work and within the pneumatic pressures the FBO's can service. Then you would have to run through the orifice sizing to make the oleo part dampen fairly well. You will want to make this accessable so you can adjust the damping.

Pazmany's Landing Gear Design for Light Aircraft, Volume 1 covers the landing loads, travel, etc. He showed a couple designs but did not provide details, nor did Volume 1 cover how to design the pieces nor how to design the damping. Unfortunately, we lost him before he wrote Volume 2. Volume 1 is kind of pricey but I bet it can be borrowed through an interlibrary loan.

The alternative is you may be able to search up a house that designs and builds pneumatic and hydraulic machinery, and they would just take your required force and travel profile , then design and build for you. You still gotta know what to ask for in terms of strut force vs travel, etc.

Billski

Thanks for the info man

 

[pylon500]

On a similar note, I have a couple of oleo gas strut nose legs from my BD-5 kits, and was looking at them for ideas for oleo's on my latest project.
Does Gerdes still exist, or anyone else that manufactures something like these?

 

[Toobuilder]

Many landing gear struts are simply telescoping 4130 tubes with die springs inside. Does not have to be hydraulic or pneumatic.

 

[wsimpso1]

Many landing gear struts are simply telecoping 4130 tubes with die springs inside. Does not have to be hydraulic or pneumatic.

Also shown in Pazmany's book.

 

[Wolfen1176]

Look for shops that rebuild and fabricate hydraulic cylinders. They might be able to make you something, but I can tell you it will probably not be cheap.

 

[opcod]

There is a place in Italy, just quickly, and they do oleo and custom size, perhaps around 3-4k. Depend on your budget.

 

[Ken Powell]

A modern motocross fork is 900 tp 950mm in length and can be easily shortened 50 to 100mm. A fork from a 'mini' will be shorter still - a KTM SX85 is an example of these bikes.