Hangar Door Cables?

[JohnDeRosa]

We had an overhead bi-fold hangar door cable snap yesterday (one of
five). Of course those on the field opened the door anyway. Sigh.

The cable had rusted through inside the guide tube on the wind up
spool. We had one hell of a time getting the old rusty cable out of
that old rusty tube. We are wondering when the other cables will
suffer the same fate.

Questions;

- What type of cable (3/16") should be used? Aviation? Stainless?
Galvanized?
- What kind of swedged stop sleeves should be used? Aluminum?
Copper? Steel?
- How to prevent rusting inside the tube? We greased the cable end in
hopes that this will help.

Thanks, John

[Frank Whiteley]

On Sunday, December 23, 2012 9:20:25 AM UTC-7, JohnDeRosa wrote:
> We had an overhead bi-fold hangar door cable snap yesterday (one of
>
> five). Of course those on the field opened the door anyway. Sigh.
>
>
>
> The cable had rusted through inside the guide tube on the wind up
>
> spool. We had one hell of a time getting the old rusty cable out of
>
> that old rusty tube. We are wondering when the other cables will
>
> suffer the same fate.
>
>
>
> Questions;
>
>
>
> - What type of cable (3/16") should be used? Aviation? Stainless?
>
> Galvanized?
>
> - What kind of swedged stop sleeves should be used? Aluminum?
>
> Copper? Steel?
>
> - How to prevent rusting inside the tube? We greased the cable end in
>
> hopes that this will help.
>
>
>
> Thanks, John

How heavy is the door? 3/16" 7/7 Galvanized Aircraft (industry term, not normally used in aircraft like 7/19) Steel Wire Rope is 3500lbs breaking strength, therefore the safe working load is a around 700lbs (1/5). I presume you have multiple ropes lifting from a driven shaft. Search on lubricating steel wire ropes. Sounds like you want grease, but you also need a penetrating lubricant. Tubes probably need a good cleaning also.

Properly swaged copper sleeves will exceed the breaking strength of the wire rope and can be done with a proper hand tool. We used aluminum when we used to winch with steel wire rope, but that was a cost consideration. In the UK, we used copper. Winching would load the rope at over twice the safe working load during launches and a splice would only fail when the three swage marks on the aluminum sleeves were worn smooth. Steel sleeves are unnecessary. I've only found them impossible to swage properly with a hand tool, requiring a hydraulic press. Maybe I need to work on the pecs more?

You could hire a door pro, but where's the fun in that? Your club has a great member involvement in projects from what I've seen.

Frank Whiteley

[BobW]

On 12/23/2012 9:20 AM, JohnDeRosa wrote:
> We had an overhead bi-fold hangar door cable snap yesterday (one of
> five). <Snip...>

> The cable had rusted through inside the guide tube on the wind up
> spool. We had one hell of a time getting the old rusty cable out of
> that old rusty tube. We are wondering when the other cables will
> suffer the same fate.

Everything else being equal, and painting with a broad brush here, the other
cables are likely "in similar condition" as the one that has already failed,
though under 25% higher load now. Maybe in summer you'd feel warmer and
fuzzier. :-)

>
> Questions;
>
> - What type of cable (3/16") should be used? Aviation? Stainless?
> Galvanized?
More "common sense engineering" follows...
- Given the service life rendered by the existing cables, anything of similar
material (you used the word "rust", so we're talking steel?) and cross section
should be in the same life ballpark. I'm sure you're aware aluminum has lower
tensile strength than steel for a given cross sectional area. Point being, you
won't go too far wrong "replacing with like." Assuming the same cross
sectional area, the number of strands affects only the minimum recommended
bend radius of whatever corners the cable must go around. More strands, more
bendy.
- In your use, my take is corrosion is your long-term enemy (Duh!). IOW, if
what's rusted rusted because it was a non-CRES steel (cheaper than CRES
steel), then pocketbook reality will need to be balanced against cable-life
realities (as in...it's rusted once, what are you going to change to preclude
rusting in the future? Personally, when I have to do "major/PITB structural
repairs" I like to do what I can to ensure the next repair need will occur
after I croak.)
- galvanized cable (if available) achieves its corrosion resistance from a
surface coating, meaning that once the coating is violated, corrosion has a
direct entry path. Presuming the interior metal is not CRES steel (else, why
coat it?), I'd do a kentucky windage guess the life of galvanized cable would
be closer to that of non-CRES bare steel cable, than of a CRES steel cable.

> - What kind of swedged stop sleeves should be used? Aluminum?
> Copper? Steel?
You won't go far wrong using a swage of similar (as possible) materials, both
for strength-matching and galvanic reasons. I'd reckon strength information is
readily available on the web for the number crunchers in your Club. In the
absence of number crunching, certainly don't go smaller than what's already
there, dry chuckle...

> - How to prevent rusting inside the tube? We greased the cable end in
> hopes that this will help.
Short of obtaining a tube of CRES material, regular usage will be your best
preventer of tube corrosion (if I'm understanding the question correctly).
Activation abrasion, if you will...

>
> Thanks, John
>

Rotsa ruck!!!

Bob W.

[bumper[_4_]]

When I had a 1/4 SS cable go on my hangar (60' wide door with but 4 cables), I had a hard time finding a place that would swage on a copper stop for a reasonable price. Swaging tools are expensive too, so I decided to make my own - - easy!

Measured dimensions of minimum OD and max OD of existing swage. Drilled a block of mild steel with min size drill. Then drilled from each side with max size drill, leaving the correct width of min size swage width in middle. Cut block in half and used as die to do the deed in a hydraulic press.

bumper

[JS]

May I suggest:
LPS3. A good rust inhibitor, leaves a slightly waxy finish but nothing that picks up dirt like grease will. At work we use it on chain hoists used indoors and outdoors, left out in the rain and chains dragged across the ground.
Aircraft Spruce sell a $20 nicopress tool that is compressed by tightening bolts.
http://www.aircraftspruce.com/catalog/topages/swagingtool.php?clickkey=9117
Jim

[Frank Whiteley]

On Sunday, December 23, 2012 11:05:09 AM UTC-7, Frank Whiteley wrote:
> On Sunday, December 23, 2012 9:20:25 AM UTC-7, JohnDeRosa wrote:
>
> > We had an overhead bi-fold hangar door cable snap yesterday (one of
>
> >
>
> > five). Of course those on the field opened the door anyway. Sigh.
>
> >
>
> >
>
> >
>
> > The cable had rusted through inside the guide tube on the wind up
>
> >
>
> > spool. We had one hell of a time getting the old rusty cable out of
>
> >
>
> > that old rusty tube. We are wondering when the other cables will
>
> >
>
> > suffer the same fate.
>
> >
>
> >
>
> >
>
> > Questions;
>
> >
>
> >
>
> >
>
> > - What type of cable (3/16") should be used? Aviation? Stainless?
>
> >
>
> > Galvanized?
>
> >
>
> > - What kind of swedged stop sleeves should be used? Aluminum?
>
> >
>
> > Copper? Steel?
>
> >
>
> > - How to prevent rusting inside the tube? We greased the cable end in
>
> >
>
> > hopes that this will help.
>
> >
>
> >
>
> >
>
> > Thanks, John
>
>
>
> How heavy is the door? 3/16" 7/7 Galvanized Aircraft (industry term, not normally used in aircraft like 7/19) Steel Wire Rope is 3500lbs breaking strength, therefore the safe working load is a around 700lbs (1/5). I presume you have multiple ropes lifting from a driven shaft. Search on lubricating steel wire ropes. Sounds like you want grease, but you also need a penetrating lubricant. Tubes probably need a good cleaning also.
>
>
>
> Properly swaged copper sleeves will exceed the breaking strength of the wire rope and can be done with a proper hand tool. We used aluminum when we used to winch with steel wire rope, but that was a cost consideration. In the UK, we used copper. Winching would load the rope at over twice the safe working load during launches and a splice would only fail when the three swage marks on the aluminum sleeves were worn smooth. Steel sleeves are unnecessary. I've only found them impossible to swage properly with a hand tool, requiring a hydraulic press. Maybe I need to work on the pecs more?
>
>
>
> You could hire a door pro, but where's the fun in that? Your club has a great member involvement in projects from what I've seen.
>
>
>
> Frank Whiteley

The right stuff
http://www.mcmaster.com/#hand-swaging-tools/=kqn118

[Frank Whiteley]

On Sunday, December 23, 2012 2:19:42 PM UTC-7, JS wrote:
> May I suggest:
>
> LPS3. A good rust inhibitor, leaves a slightly waxy finish but nothing that picks up dirt like grease will. At work we use it on chain hoists used indoors and outdoors, left out in the rain and chains dragged across the ground.
>
> Aircraft Spruce sell a $20 nicopress tool that is compressed by tightening bolts.
>
> http://www.aircraftspruce.com/catalog/topages/swagingtool.php?clickkey=9117
>
> Jim

I love LPS products, but I might suggest Boeshield for this. I've used it on our club winch and my bikes. Next spring I think I'll try it on my garage door.
http://boeshield.com/
Available widely, even via Amazon
http://www.amazon.com/Boeshield-T-9-Lubricant/dp/B008H5DB88

[RAS56]

John,

I had a similar circumstance happen on a 50' Hi-Fold door on my hangar some years back.

Because of all the suspended weight these cables support and not wanting to put up with the possibility of injuring/killing someone or damaging property if I put in a substandard spec'ed cable, I ordered replacement cable from Hi-Fold Doors.

http://www.hi-fold.com/

Bet you that they can at least give you a good recommendation...I know they had all the parts needed to get my door working like a champ again.

Best,

Rob Schroer
ZAP

[[email protected]]

I recommend http://www.goxu.com.tr/hangar_kapilari
On Sunday, December 23, 2012 6:20:25 PM UTC+2, JohnDeRosa wrote:
> We had an overhead bi-fold hangar door cable snap yesterday (one of
>
> five). Of course those on the field opened the door anyway. Sigh.
>
>
>
> The cable had rusted through inside the guide tube on the wind up
>
> spool. We had one hell of a time getting the old rusty cable out of
>
> that old rusty tube. We are wondering when the other cables will
>
> suffer the same fate.
>
>
>
> Questions;
>
>
>
> - What type of cable (3/16") should be used? Aviation? Stainless?
>
> Galvanized?
>
> - What kind of swedged stop sleeves should be used? Aluminum?
>
> Copper? Steel?
>
> - How to prevent rusting inside the tube? We greased the cable end in
>
> hopes that this will help.
>
>
>
> Thanks, John



On Sunday, December 23, 2012 6:20:25 PM UTC+2, JohnDeRosa wrote:
> We had an overhead bi-fold hangar door cable snap yesterday (one of
>
> five). Of course those on the field opened the door anyway. Sigh.
>
>
>
> The cable had rusted through inside the guide tube on the wind up
>
> spool. We had one hell of a time getting the old rusty cable out of
>
> that old rusty tube. We are wondering when the other cables will
>
> suffer the same fate.
>
>
>
> Questions;
>
>
>
> - What type of cable (3/16") should be used? Aviation? Stainless?
>
> Galvanized?
>
> - What kind of swedged stop sleeves should be used? Aluminum?
>
> Copper? Steel?
>
> - How to prevent rusting inside the tube? We greased the cable end in
>
> hopes that this will help.
>
>
>
> Thanks, John



On Sunday, December 23, 2012 6:20:25 PM UTC+2, JohnDeRosa wrote:
> We had an overhead bi-fold hangar door cable snap yesterday (one of
>
> five). Of course those on the field opened the door anyway. Sigh.
>
>
>
> The cable had rusted through inside the guide tube on the wind up
>
> spool. We had one hell of a time getting the old rusty cable out of
>
> that old rusty tube. We are wondering when the other cables will
>
> suffer the same fate.
>
>
>
> Questions;
>
>
>
> - What type of cable (3/16") should be used? Aviation? Stainless?
>
> Galvanized?
>
> - What kind of swedged stop sleeves should be used? Aluminum?
>
> Copper? Steel?
>
> - How to prevent rusting inside the tube? We greased the cable end in
>
> hopes that this will help.
>
>
>
> Thanks, John