F-24 strut repair

Tom-D

Taxi to Parking
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Tom-D
A F-24 owner sent me these because he didn't like the way the struts were leaking oil.
 

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Tom-

I would sent those specs. to www.coilsprings.com and see what they say.

Those seals shouldn't be a problem either. I get a lot of obsolete hydraulic cylinder seals made and they are not too bad on price.

How are the strut barrels? Chrome or steel or ?

Interesting work.
 
Tom-

I would sent those specs. to www.coilsprings.com and see what they say.

Those seals shouldn't be a problem either. I get a lot of obsolete hydraulic cylinder seals made and they are not too bad on price.

How are the strut barrels? Chrome or steel or ?

Interesting work.

These are not pressurized hydraulic struts, they are oil dampened spring, they really don't need a tight seal, oil level is well below the gland nut.

I make rubber bumper for the strut piston to gland nut seal it acts more of a cushion than a seal/

thanks for the link.

We are asking for a quote here too.

http://www.cannonracecraft.com
 
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Anyone like to venture a guess why the springs broke?
 
Lack of oil in the strut so no dampening action?
 
Lack of oil in the strut so no dampening action?

They were totally full of oil, that is why they were leaking.

Clue, they were sent to me from Alaska.
 
Dayton Progress comes close, but the largest die spring they list is 2 inch. They have an EH200-800. 2 inch diameter, 8 inch free length and 2,370# at 2 inch compression. Maybe they could use the extra "oomph" in Alaska...

Catalog at this link.
 
Water in the oil, which froze, then the springs broke on the ice...
 
Extreme cold temps / rough fields Is my guess too.
 
An update
The springs are being made in Portland Or. should be done this month.

Ready to assemble

Manufactured two upper tubes cleaned the lower strut and had them cad plated type 2 with a 24 hour bake, made two new rubber seals for the lower struts, rebushed 4 swivels and lapped to fit new bolts to attach the struts to the aircraft and gear legs. ($904.00) plus shipping.
 

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An update
The springs are being made in Portland Or. should be done this month.

Ready to assemble

Manufactured two upper tubes cleaned the lower strut and had them cad plated type 2 with a 24 hour bake, made two new rubber seals for the lower struts, rebushed 4 swivels and lapped to fit new bolts to attach the struts to the aircraft and gear legs. ($904.00) plus shipping.

Tom-

You manufactured two upper tubes?

How did you fabricate the seals?

Are you saying you did this job turn key, new springs, etc. all for $904????

If so someone needs to put you on their Christmas list.
 
Tom-

You manufactured two upper tubes?

How did you fabricate the seals?

Are you saying you did this job turn key, new springs, etc. all for $904????

If so someone needs to put you on their Christmas list.
The fabrication of the springs was arranged by the owner, he found a company that would make them as per the blue print, that's separate from my bill for time and expenses.
I bought the steel tubing, rubber blocks, bushing material, the new plating, and charged for their cost plus my labor. which included the trip costs to deliver the lower struts to the plating facility in Seattle.

and have already received the check. :)
 
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The fabrication of the springs was arranged by the owner, he found a company that would make them as per the blue print, that's separate from my bill for time and expenses.
I bought the steel tubing, rubber blocks, bushing material, the new plating, and charged for their cost plus my labor. which included the trip costs to deliver the lower struts to the plating facility in Seattle.

and have already received the check. :)

on my lathe, using a dremil tool and a rotary cutter.

Tom-

Did you use DOM tubing and then finish hone it?

Cutting your own seals.... Nice. What kind of rubber did you use?

Great project the owner must be thrilled.
 
Tom-

Did you use DOM tubing and then finish hone it?

Cutting your own seals.... Nice. What kind of rubber did you use?

Great project the owner must be thrilled.

I hope you realize that they are not a sealing type of seal. they are more of a rubber bumper that when you pinch it with the gland nut it swells and stops the oil from splashing out the top of the strut. and cushions the piston stop during the extension. It is nothing more than a rubber block that we buy from a jewelers supply shop.

the OEM Fairchild seal was a chunk of plumbers rope caulk.
 
I hope you realize that they are not a sealing type of seal. they are more of a rubber bumper that when you pinch it with the gland nut it swells and stops the oil from splashing out the top of the strut. and cushions the piston stop during the extension. It is nothing more than a rubber block that we buy from a jewelers supply shop.

the OEM Fairchild seal was a chunk of plumbers rope caulk.

OK got it. I've never been near a Fairchild so I have no idea. Sounds like a really basic oil dampening system.
 
I hope you realize that they are not a sealing type of seal. they are more of a rubber bumper that when you pinch it with the gland nut it swells and stops the oil from splashing out the top of the strut. and cushions the piston stop during the extension. It is nothing more than a rubber block that we buy from a jewelers supply shop.

the OEM Fairchild seal was a chunk of plumbers rope caulk.

Why not replace it with packing gland material then?
 
Tom, I really appreciate you posting these things. While I have never developed the kind of skills you have, I still cherish the craft of repairing and renewing old things to work again, and it is fun to watch you at work. If you aren't proud of your work, you're missing out - it is a high form of art.
 
Tom, I really appreciate you posting these things. While I have never developed the kind of skills you have, I still cherish the craft of repairing and renewing old things to work again, and it is fun to watch you at work. If you aren't proud of your work, you're missing out - it is a high form of art.

Thanks for that.. major part of my business is this sort of stuff, that and recovery of flight controls.
 
Guess what I got from the UPS truck today.
 

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But they don't fit.
 

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Well, crud.

Dimensions in drawings adhered-to?

They are prefect by the drawing, we must have two sizes of gear struts that no one knew about..

Oh the fun of working on the antiques.
 

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They are prefect by the drawing, we must have two sizes of gear struts that no one knew about..

Oh the fun of working on the antiques.

So now what, measure the old springs and have them built to that spec?
 
So now what, measure the old springs and have them built to that spec?

Today we see what the owner wants to do.

problem is the spring manufacturer must set up to do a run of the type spring they will be making, the set up time is not cheap.
 
I think a micrometer check of the old springs versus the drawings would have probably saved a bunch of time and aggravation.

Measure twice, cut once?
 
I think a micrometer check of the old springs versus the drawings would have probably saved a bunch of time and aggravation.

Measure twice, cut once?

Exactly, I'm assuming the owner handled the spring fabrication separately from the rebuild Tom did.
 
See post #9 above. Looks pretty close now.

Of course "close" may not be good enough for the FAA...
 
No one in the type club knew there is two different sizes of lower barrels for the F-24.

The print gives the models it applies to, and the F-24-W&R-9 is the same as the early models.

I informed the owner that he was ordering a spring that was not the same as the ones that came out.

sent him pictures of the springs that came out, and the print. no one has a print of the square coiled type, it isn't even shown in the over 4000 prints that I have of the F-24.
 
No one in the type club knew there is two different sizes of lower barrels for the F-24.

The print gives the models it applies to, and the F-24-W&R-9 is the same as the early models.

I informed the owner that he was ordering a spring that was not the same as the ones that came out.

sent him pictures of the springs that came out, and the print. no one has a print of the square coiled type, it isn't even shown in the over 4000 prints that I have of the F-24.

Could it perhaps have been one of those midnight repairs/modifications that were done a long, long time ago without benefit of log entry? You said it was an Alaska airplane; I've seen some bushplane mods that didn't exactly conform to type.
.


Jim
 
Could it perhaps have been one of those midnight repairs/modifications that were done a long, long time ago without benefit of log entry? You said it was an Alaska airplane; I've seen some bushplane mods that didn't exactly conform to type.Jim

I don't believe that this the case. It looks exactly like any early version of the 22-24 lower barrel. I'm trying to find two later version barrels to see if they are bigger.
 
To continue this, the owner had the spring manufacturing company manufacturer a new set of springs that fit the struts and I have assembled the two struts and shipped them. All was well until the shipper damaged them during transit. I did insure them, and now the A&P receiving them will get paid to repair the scratches made to them by the shipper.
 

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