I discovered many years ago when I was building…that the ‘spring’ that holds an oil seal…(for engines and related equipment) made a fabulous ‘hose’ for airplane engines. I used to give them away at a model club I belonged to and they ate them up.
If you aren’t sure what I’m referring to, I can elaborate.
There may well be a better alternative on the market by now…but it would be hard to replace these.
If I’m off-base…let me know…or if you need more info…I will supply it.
Nam
Good tip Nam! I may have to go look for one of those and try it out. One question, are the springs the same size in all of the seals, or does one need to measure what diameter they need and shop/ask around accordingly?
I’ve used something very similar. My old job sometimes involved the use of spring plunger contacts for use in test fixtures, made by a company called Ostby-Barton. If the plunger was bent to the point where it would no longer retract smoothly, I would drill out the plunger from the opposite end and pull out the spring…and some were quite small, maybe 1/4" to 3/8" in length and diameters ranging from .036" down to .017". They make excellent fender return springs for panzer IV’s as well as inline shock springs for antenna wires and canopy cables. To use them as hoses, I would slip a piece of stiff wire into them so they would hold their shape, and ‘paint’ them with a water/white glue mixture, then install them and paint as usual.
Hey How are you?
Generally…the larger the diameter of the seal, the thicker the spring. Usually the thickness ranges from around .030" to slightly over an eighth inch.
Don’t go buy new seals for this purpose! That ruins the ‘scrounging’ aspect![;)]
Simply befriend a service station owner or mechanic, or an electric motor repair place and ask them to toss old seals in a bag for you. You would be amazed how quickly they pile up. They are just tossed away, anyhow.
They can be tricky to glue in place when making a radical bend in the hose (spring), but with the range of adhesives around…it’s not that tough.
I used to drill a small ‘socket’ with a pin vice to anchor one end…mount it and let dry thoroughly and then anchor the other end in the desired location.
Of course, the spring is in a circle when you pluck it off the seal…snip it and it straightens out. You practically need a magnifying glass to find any separation in the coils even after a very tight bend.
Oh! Thouroughly clean and dry the spring to get any oil residue out in case you want to paint it.
Hope this helps!
Nam
That’s a neat idea too rudd!
This sounds very interesting, but I have no idea what the spring looks like. Does anyone have a picture to share with mechanical novice like me?
It looks, well like a spring…but a very tight spring. If you pulled each end of it it would stretch out into a twisted piece of wire, so don’t do that. Otherwise it looks like a ribbed piece of hose…and being made of metal, it looks very realistic in it’s natural state and is as flexible as rubber…in a cockpit or engine compartment…just about anywhere you could imagine a piece of hose in a model.
The colors range from silver, to black, dark grey, and sometimes a brassy color, and as I say…coils of these springs are so tightly wound that they take paint very well when cleaned. I used to just drybrush highlights and such.
Here is a link to a seal mfr. The cutaway view of a typical seal shows the spring as the silver colored component…the spring wraps around a noeprene seal and keeps the neoprene in contact with whatever round shaft it is applied to. The springs own tension keeps it in place and you can just remove it with your fingers or even pry it out with even a toothpick.
That is a great idea. I have worked around helicopters and used to take the spring apart and make it smaller. All the seals that I worked on have the spring that comes apart. Looking under a magnifying glass you can find where the spring comes apart. Most springs are right hand thread so if you grap close to the joint area and unscrew the ends you will have one end tapered where it goes into the female end. If you tighten it then most of the time you will have to cut the spring.
Small airports might be source of old seals also.
Ed
I’ve also seen/heard/done, if you wrap it with plumbers Teflon Tape then paint it, it works pretty good as oxy,heat and any others of that type.
Yes…I’ve seen those seals…they were usually quite large as I remember…I believe they used them in helicopter engines alot. The types I have been describing are used on smaller rotating parts in auto engines and electric motors where you need to keep grease or lube oil from leaking out.
Yup…any airport with a maintenence facility would have a ton seals to toss away. Even if spring failure is the cause of a seal going bad…the spring is still useable for modeling purposes in most cases.
To GulfstreamV: That is a neat idea with the teflon tape! Never thought of that!
This is probably more info than anyone needs about mechanical seals…but thanks for your interest and sharing!
Nam
There is no need to get elaborate trying to find these seals. The type is used in everything and can be found probably by the bag in the afore mention auto shop. Any place that does wheel bearings like brake shops (Midas) should have plenty of these they throw away everyday. Trailer bearings are also a good source.
I’m glad someone mentioned the idea because I work in a boat shop and see these seals all the time. BUt I never had the spark of inspiration to use them. I’ll be collecting them from now on!
Cool post!
Yep, I was building, I think a P-39 and my In Action book showed this big hose somewhere and the next day I happened to disassemble a motor and the spring fell out in my hand!..the proverbial lightbulb went off. …or ‘on’…whichever
yep, tried it . Very good idea. I work with this stuff all the time, and it never dawned on me to try it. thanks for the tip!!