Turning Rubber Round Stock ?????

[boslab]

I know the washers, dowty seals is what I call them, very handy on hydraulic pipes
Mark

[lbhsbz]

I find it easier to turn a couple of "cookie cutters" and then cut the washers out of sheet using either the press or even a vice. I use whatever steel tube I can find for the cutter, then a flat chunk of aluminum as a backer behind my stock.

[ikdor]

As long as you stay with the high durometer rubbers, there's no need to bother with the freezer or other things. Just use sharp tools.
We have a seal lathe somewhere in the building that makes all kind of custom seals straight from stock.
I do think the lower limit is something like 70 shore.

Igor

[EddyCurr]

Would O-Ring Boss (ORB) fittings or something HSM'd
that resembles them meet the needs of your application,
JL ?

I'm not familiar with ORB type fittings.

JL............

Oops, ORB fittings are not appropriate for your intended
usage. These are fluid couplings (like AeroQuip) that
have straight thread and o-rings in lieu of pipe threads
for attachment to components.

Reviewing the initial post, I am reminded the object is
to seal screws, not fluid fittings.

Sorry.

.

[Lew Hartswick]

There are screws with the washer already built in. Look up apm hex seal.

THAT'S the name I was trying to remember. :-)
...lew...

[beanbag]

There are screws with the washer already built in. Look up apm hex seal.

[Beazld]

Google sealing washers. Lowes has rubber sealing washers #8X1/2" for about $6/100. They are rubber washers bonded to steel washers. Another suggestion for all rubber washers is check out the plumbing section of the local big box for flat faucet washers. Come in many sizes.

[GKman]

I just made some. For the ID, I place the sheet rubber on the drill press, clamp a board tight down on it and drill through with a woodworking Forstner bit. A hole saw would likely work, too. I just scissored the OD but I have pinched between two scraps between headstock and tailstock and turned the od.

[Noitoen]

Try these.

[darryl]

CalM mentioned capturing the rubber part, preventing it from blowing out basically. You can do that by placing a very short section of thinwall tubing around the screw head. As you expand the O-ring by tightening the screw, it expands to capture the piece of tubing. You could wick a drop of CA between the screw head and the ring of tubing for more assurance that this extra part will stay in place.

You could make the rubber washer and capture it the same way. What could be good about this is that the same tubing you might use to retain the expansion of the rubber could be sharpened on the end and used to cut the washer out in the first place. I use this method often when I need to make a rubber washer. Twirl the sharp end of the tubing into the rubber sheet and it very neatly cuts out a nice round part. For the tubing, I've mostly used telescoping antenna rod from radios, tv rabbit ears, etc. Some rabbit ears use stainless tubing- Sony was good for making theirs from this- mostly you'd find chrome plated brass tubing.

The hardest part about cutting out a rubber washer using this method is the second op, which would be cutting a centered hole in the washer. Not hard really, you just have to make up a centering jig.

[JoeLee]

Gasket sheet material will be ideal!

A snug fit on the screw shank, OD doesn't matter.

I punch those out of sheet material with arch and flat punches into end grain soft wood!

I thought of punching some out of sheet material.
I also need a snug fit around the screw as well as under the head. I think buna O-rings may be too soft. I dont' know if O-rings come in different hardness.

JL..............

[JoeLee]

Would O-Ring Boss (ORB) fittings or something HSM'd
that resembles them meet the needs of your application,
JL ?

.

I'm not familiar with ORB type fittings.

JL............

[CalM]

#6 or #8? Use fiber! not rubber

The O-rings might just be the way to go. These have to go under the head of a #6 and #8 pan head screw. Cutting a groove on the underside of the head would be a challenge, just the set up alone would be, but a thin O-ring would do the job just fine providing they don't blurp out when the screw it tightened. That's why I chose the harder durometer neoprene.
I guess I'll have to experiment a little.
I did check McMaster and that is where I found the neoprene rod.

JL................

Gasket sheet material will be ideal!

A snug fit on the screw shank, OD doesn't matter.

I punch those out of sheet material with arch and flat punches into end grain soft wood!

[EddyCurr]

Would O-Ring Boss (ORB) fittings or something HSM'd
that resembles them meet the needs of your application,
JL ?

Edit: disregard - irrelevant to the OP's intended application

.

[JoeLee]

But if you want to seal under a fastener, you MUST capture the rubber part.

My favorite is an O-ring with a washer that has a hole large enough to contain the o-ring, but snall enough to stay completely under the fastener head.
These can be purchased.

A "cleaner" job is with an o-ring groove cut into the underside of the fastener head.

The O-rings might just be the way to go. These have to go under the head of a #6 and #8 pan head screw. Cutting a groove on the underside of the head would be a challenge, just the set up alone would be, but a thin O-ring would do the job just fine providing they don't blurp out when the screw it tightened. That's why I chose the harder durometer neoprene.
I guess I'll have to experiment a little.
I did check McMaster and that is where I found the neoprene rod.

JL................