Shock absorbers for 80% replica AVIA B-534

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Svetlio_i

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Jan 19, 2022
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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 :

1654612852008.png

I have done a little sketch how this need to look
1654613458093.png

Did someone know where I can get them made ?
Thanks
 

Vigilant1

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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.
1654614064269.png
 

Svetlio_i

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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

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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
 

Svetlio_i

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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
 

wsimpso1

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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

Active Member
Joined
Jan 19, 2022
Messages
29
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

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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?
BD-5noseleg.png
 

Wolfen1176

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Apr 10, 2021
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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

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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

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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.
 
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