Home Made "O" Rings?

[John Keiser]

I know this is off-topic but you folks are very clever and may have a
solution.

My swimming pool sand filter is 30 years old. Parts no longer available.
The valve has begun to leak from a "spider" gasket - basically an 8 inch "O"
ring and a "1 inch "O" ring connected by 3 radials [which separate
rinse/filter/backwash chambers]. The gasket must allow the valve body to
rotate to the three positions so I doubt anything as simple as silicone
caulk would work.
No comparable part available AFAIK.
Replacing the sand filter would not only be pricey, but labor intensive.
Does any one have experience making [or piecing together] such a gasket? Or
a link that might help?
Thanks for any wisdom.

 

[[email protected]]

Most car/auto/engineering supplies shops have DIY "O" ring kits.These
are made from round rubber and joined using cyno adhesive.Search the
web for DIY "O" ring kits.
Regards

 

[John Keiser]

Thanks for the lead.
The vulcanizing O-ring kits are in the $1000 range. Might work but not
economical for one repair.
The crazy glue method would likely fail due to the water/chlorine
environment.
I'll search some more.

 

[GregS]

I know this is off-topic but you folks are very clever and may have a
solution.

My swimming pool sand filter is 30 years old. Parts no longer available.
The valve has begun to leak from a "spider" gasket - basically an 8 inch "O"
ring and a "1 inch "O" ring connected by 3 radials [which separate
rinse/filter/backwash chambers]. The gasket must allow the valve body to
rotate to the three positions so I doubt anything as simple as silicone
caulk would work.
No comparable part available AFAIK.
Replacing the sand filter would not only be pricey, but labor intensive.
Does any one have experience making [or piecing together] such a gasket? Or
a link that might help?
Thanks for any wisdom.

I'm not sure what this looks like. What part has broke, and how often does it
rotate.

greg

 

[[email protected]]

I know this is off-topic but you folks are very clever and may have a
solution.

My swimming pool sand filter is 30 years old. Parts no longer available.
The valve has begun to leak from a "spider" gasket - basically an 8 inch "O"
ring and a "1 inch "O" ring connected by 3 radials [which separate
rinse/filter/backwash chambers]. The gasket must allow the valve body to
rotate to the three positions so I doubt anything as simple as silicone
caulk would work.
No comparable part available AFAIK.
Replacing the sand filter would not only be pricey, but labor intensive.
Does any one have experience making [or piecing together] such a gasket? Or
a link that might help?
Thanks for any wisdom.

Would a silicone sealant from a tube do the job?

 

[ABLE_1]

Go here and type o-ring in the search. http://www.mcmaster.com/ You will
find more choices than on person can handle at any one time.

Get very accurate on the cross section diameter and measure the inside and
outside of the o-ring. If it is broken you may need to measure the length
and do some geometry math to determine the diameter. If all else fails call
a local bearing/mechanical supply house they can get rings custom made. You
will have to decide if the price of a custom o-ring is better than replacing
the filter. Good luck.

 

[John Keiser]

Thank you all for the suggestions. [Mcmaster-Carr is great!].
The valve rotates only when backwshing - so a few times each month. But
still, not static.
In speaking with RocketSeal, it appears a custom "vulcanized" gasket would
cost several hundreds of $$ just for the jig. [The radial sections between
the inner and outer O-ring complicates this fabrication.]
I could make a wooden mold with a router but I doubt I could pour a durable
gasket.
Since rotation is minimal, before I give up, I may try to fabricate a gasket
of appropriate thickness.
Again, I appreciate your ideas!

 

[JANA]

For some industries, there is available gasket rubber. You can cut out your
own gaskets. Check this out at any of the major hardware centres. Actually,
any type of medium soft rubber sheet will work. You just have to find a way
to accurately cut your own gasket from it.

Many of the automobile centres who service the older cars will carry gasket
rubber sheeting. When I was working in engine rebuilding, I used to use to
make my own gaskets at times. I would doubt they spend a thousand bucks to
make a gasket. If so, the client would blow his gasket!

--

JANA
_____


I know this is off-topic but you folks are very clever and may have a
solution.

My swimming pool sand filter is 30 years old. Parts no longer available.
The valve has begun to leak from a "spider" gasket - basically an 8 inch "O"
ring and a "1 inch "O" ring connected by 3 radials [which separate
rinse/filter/backwash chambers]. The gasket must allow the valve body to
rotate to the three positions so I doubt anything as simple as silicone
caulk would work.
No comparable part available AFAIK.
Replacing the sand filter would not only be pricey, but labor intensive.
Does any one have experience making [or piecing together] such a gasket? Or
a link that might help?
Thanks for any wisdom.

 

[mm]

For some industries, there is available gasket rubber. You can cut out your
own gaskets. Check this out at any of the major hardware centres. Actually,
any type of medium soft rubber sheet will work. You just have to find a way
to accurately cut your own gasket from it.

Many of the automobile centres who service the older cars will carry gasket
rubber sheeting. When I was working in engine rebuilding, I used to use to
make my own gaskets at times. I would doubt they spend a thousand bucks to
make a gasket. If so, the client would blow his gasket!

Then you could use the tool a second time. That would make it only
500 dollars a gasket.
Remove NOPSAM to email me. Please let
me know if you have posted also.

 

[David C. Partridge]

RS Components in UK do an O ring kit to make up your own O rings - this has
worked well for me in the past. Cyano-acrylate gluing of the butyl-nitrate
rubber hasn't failed on any I've made up (so far - in some cases over 10
years).

I'm sure that equivalent kits are available elsewhere.

Dave

 

[GregS]

Go here and type o-ring in the search. http://www.mcmaster.com/ You will
find more choices than on person can handle at any one time.

Also for O rings,

Small Parts Inc.

MSC

I would also lube the rings with silicon grease, stopcock grease, and
or, high vacuum grease.

greg

Get very accurate on the cross section diameter and measure the inside and
outside of the o-ring. If it is broken you may need to measure the length
and do some geometry math to determine the diameter. If all else fails call
a local bearing/mechanical supply house they can get rings custom made. You
will have to decide if the price of a custom o-ring is better than replacing
the filter. Good luck.

I know this is off-topic but you folks are very clever and may have a
solution.

My swimming pool sand filter is 30 years old. Parts no longer available.
The valve has begun to leak from a "spider" gasket - basically an 8 inch
"O" ring and a "1 inch "O" ring connected by 3 radials [which separate
rinse/filter/backwash chambers]. The gasket must allow the valve body to
rotate to the three positions so I doubt anything as simple as silicone
caulk would work.
No comparable part available AFAIK.
Replacing the sand filter would not only be pricey, but labor intensive.
Does any one have experience making [or piecing together] such a gasket?
Or a link that might help?
Thanks for any wisdom.

 

[Michael A. Terrell]

I know this is off-topic but you folks are very clever and may have a
solution.

My swimming pool sand filter is 30 years old. Parts no longer available.
The valve has begun to leak from a "spider" gasket - basically an 8 inch "O"
ring and a "1 inch "O" ring connected by 3 radials [which separate
rinse/filter/backwash chambers]. The gasket must allow the valve body to
rotate to the three positions so I doubt anything as simple as silicone
caulk would work.
No comparable part available AFAIK.
Replacing the sand filter would not only be pricey, but labor intensive.
Does any one have experience making [or piecing together] such a gasket? Or
a link that might help?
Thanks for any wisdom.

Check with heavy equipment repair places. (Bull dozer, front end
loaders, etc.) They carry a wide variety of O-rings. If they have one
with the right diameter, but too big you can cut out some of the rubber
and glue the ends together.

 

[Smitty Two]

Have all you respondents that are recommending sources for O-rings
really read the OP's post? He doesn't want an O-ring, he wants TWO
O-rings, of different diameters, *connected* by 3 radials, all as ONE
unit.

I'd think a decent machinist could make an aluminum mold for $150 or so,
if you can find some liquid O-ring goo to pour in there. A couple of
flat plates, a ball end mill, an entry level CNC, and you're done. Hell,
you don't even need the CNC if you know how to use a rotary table, but
it takes longer.

MIght need to spend a little time with an X-acto knife to trim the
flashing.

 

[Steve Noll]

I know this is off-topic but you folks are very clever and may have a
solution.

My swimming pool sand filter is 30 years old. Parts no longer available.
The valve has begun to leak from a "spider" gasket - basically an 8 inch "O"
ring and a "1 inch "O" ring connected by 3 radials [which separate
rinse/filter/backwash chambers]. The gasket must allow the valve body to
rotate to the three positions so I doubt anything as simple as silicone
caulk would work.
No comparable part available AFAIK.
Replacing the sand filter would not only be pricey, but labor intensive.
Does any one have experience making [or piecing together] such a gasket? Or
a link that might help?
Thanks for any wisdom.

The problem is, even if you patch something together the rest of the
valve and the filter tank are still 30 years old. Ripe for Murphy
rearing his ugly head and causing a crack in the obsolete valve a
month down the road. I'd reconsider replacing the whole thing and
buying a spare set of gaskets for it.

I see a lot of 6 radial spider gaskets for current filters and wonder
if they're close enough to modify.
..
Steve Noll | The Glass Block Pond
| http://www.kissingfrogs.tv

 

[Michael A. Terrell]

Have all you respondents that are recommending sources for O-rings
really read the OP's post? He doesn't want an O-ring, he wants TWO
O-rings, of different diameters, *connected* by 3 radials, all as ONE
unit.

I'd think a decent machinist could make an aluminum mold for $150 or so,
if you can find some liquid O-ring goo to pour in there. A couple of
flat plates, a ball end mill, an entry level CNC, and you're done. Hell,
you don't even need the CNC if you know how to use a rotary table, but
it takes longer.

MIght need to spend a little time with an X-acto knife to trim the
flashing.

Gee, Smitty, if you can glue the ends of the gasket material together
o make an "O" ring, you can also glue the radials in place. At least, I
would do it for something of mine that I needed really bad. The seals
were bad on the whole house water filter when I moved into this house,
but the plastic threads on the cartridge housing were so badly worn that
the entire system was scrapped. It wasn't worth rebuilding a 20 year
old system that used VERY hard to find filter cartridges when you knew
that the hairline cracks in the clear molded plastic cartridge cover
would spread into full blown cracks and leak some day soon. I could
have even made a new cover out of some clear 4" plastic pipe I had on
hand, but why piece together a piece of worn out junk?

 

[Smitty Two]

Gee, Smitty, if you can glue the ends of the gasket material together
o make an "O" ring, you can also glue the radials in place. At least, I
would do it for something of mine that I needed really bad. The seals
were bad on the whole house water filter when I moved into this house,
but the plastic threads on the cartridge housing were so badly worn that
the entire system was scrapped. It wasn't worth rebuilding a 20 year
old system that used VERY hard to find filter cartridges when you knew
that the hairline cracks in the clear molded plastic cartridge cover
would spread into full blown cracks and leak some day soon. I could
have even made a new cover out of some clear 4" plastic pipe I had on
hand, but why piece together a piece of worn out junk?

In your case, a wise decision. Who's to say whether the OP's equipment
*is* or *is not* worth re-gasketing? Maybe it's about to disintegrate,
and maybe a new seal would get him another 30 years of service out of it.

I've made O-rings by gluing ends together, but those were for static
applications. Wasn't the OP talking about moving parts? That might make
the "glue it together out of multiple pieces" approach a mite tenuous.
Perhaps I've misunderstood, though.

I just thought I heard some fairly high numbers thrown out by someone,
for a one-off mold that seems pretty simple to me, that's all.

 

[James Sweet]

Have all you respondents that are recommending sources for O-rings
really read the OP's post? He doesn't want an O-ring, he wants TWO
O-rings, of different diameters, *connected* by 3 radials, all as ONE
unit.

I'd think a decent machinist could make an aluminum mold for $150 or so,
if you can find some liquid O-ring goo to pour in there. A couple of
flat plates, a ball end mill, an entry level CNC, and you're done. Hell,
you don't even need the CNC if you know how to use a rotary table, but
it takes longer.

MIght need to spend a little time with an X-acto knife to trim the
flashing.

How much does it cost to just replace the filter unit? I'm all for
fixing something but if it comes down to this extreme, and modern
versions are readily available then why?

 

[Smitty Two]

How much does it cost to just replace the filter unit? I'm all for
fixing something but if it comes down to this extreme, and modern
versions are readily available then why?

intensive.

I guess he's the only one in a position to evaluate the pros and cons of
repair or replacement.

 

[H. P. Friedrichs]

John,

I'd exhaust all of your other options first. Then, if I struck out, I'd
try molding my own part:

a) I'd get a piece of hardwood...something with a nice tight grain.

b) I'd take a router, and route the pattern I wanted into the wood. This
is the mold.

c) I'd oil the wood...mineral oil, maybe? This should act as a mold release.

d) I'd get a cartridge of silicone RTV, put it in my caulking gun, and
lay down a nice heavy bead in the mold.

In your case, you might consider using one of the automotive
RTVs...black or red types...those are used in more chemically hostile
environments so they may have stabilizing compounds that might work to
your benefit in the chlorine-rich environment of the pool pump.

You can get RTV rubber in sheets, IIRC. Another possibility would be to
lay out a pattern on the sheet, and then carefully cut it out with
scissors and/or a sharp knife.

I don't know if any of this would work, but hey...It might be worth trying.

Pete
www.hpfriedrichs.com