Gasket maker (and etc)

[Cat966c]

Hey all

I was wondering: would gasket maker material and the other stuff (steel stik, epoxy, rtv silicone, 100 percent silicone) work for making my own o rings?
I know the steel stik and the epoxies are strong enough (700-4000 psi)

Thanks!

[ddmckee54]

Rings for what? That will have a LOT to do with whether or not it would work.

[Cat966c]

For a hydraulic piston ��‍♂️

[Flycop2000]

Would it not be easier to just buy O rings? They are not expensive.

[ddmckee54]

For a hydraulic piston just use a store-bought o-ring. From Ebay, Amazon, Aliexpress, or the dozens of other sites they can be had for about a dime a dozen if you look around. It isn't worth the hassle of trying to fabri-cobble a custom o-ring.

That stuff has its' uses, but this really isn't one of them. I used the high temp stuff from NAPA, in a 3D printed mold, to make a silicone boot for my 3D printer hot block. Still using it over a year later, it's probably got a couple hundred hours of use on it by now.

[Cat966c]

Well: what if it’s an in between size?

And would this be ok? It’s neoprene rubber washer that’s cut to size, but it’s not exact all around, but it fits inside snugly and I’m using two per piston

[Cat966c]

[crueby]

I'd check someplace like The O Ring Store - they have an enormous selection of all types of rings and seals.

[Cat966c]

But would that �� and the other stuff I said work?

[Lil Giants]

Put it together, try it - find out,

[Lil Giants]

This how a piston should look, double o-ring; as well as double o-ring inside the cyl cap so oil doesn't seep past the rod. You can see another thin o-ring on the outside of cap that seals it when seated in the barrel.

[Cat966c]

Originally Posted by Lil Giants

This how a piston should look, double o-ring; as well as double o-ring inside the cyl cap so oil doesn't seep past the rod. You can see another thin o-ring on the outside of cap that seals it when seated in the barrel.

Beautiful.
Yeah that’s what I’m interested in. The piston rod seals themselves: would mine above work, especially since I’m using 2??
They each fit pretty snugly, so I hope together they give me a good seal

[Lil Giants]

I would guess no bc outer diameter is not uniform.

You can buy cyl kits from Fumotec, make each cyl any length - stroke you want.
info@fumotec.de

[frizzen]

If you're going to do it the hard way, can you make a gasket punch? Sharpen a tube with the right ID for the OD you'd like the gasket to have. It'll have more of a fighting chance at sealing than handcut.

If you sacrifice a bigger o-ring the diameter you need, roll your own
https://youtu.be/d0uuSNGkYJY
(I believe it's Rubberized CA, rc car tire glue)
'Ave' had a better video on making them, but i can't find it

[Cat966c]

Thanks!
So no it wouldn’t work, even if it’s double o rings handcut???
Yeah, I thought about doing the punch thing

[Cat966c]

And what about pourable stuff? Would any of that work for an o ring?

[Cat966c]

Bump

[Rimrock]

There are pretty tight tolerances concerning hydraulic seals and the grooves they are fitted in. The seal on a piston or rod works that way that oil under pressure are to come in behind the seal, often a 'o-ring, and push it towards the rod, or cylinder wall for a piston seal. It's not the pure friction of a seal towards a surface that does the main sealing alone here, so a gasket being 'tight' on to a rod doesn't mean it will seal under pressure (can seal to a certain degree if there are no pressure, or quite low pressure) (Not all manufacturers of RC hydraulics follows, or maybe are aware of, these principles, like Magom that preferes using quite 'beefy' soft o-rings and not letting any oil come in on the backside helping make a tighter seal, and it works quite okay)
Of course it is allowed to try make one owns gaskets, but as few/none make their own o-rings, there are little experience about what materials and how to make them. O-rings are mainly made of neoprene, a compund similar to natural rubber but more durable. Material for o-rings can be purchased on a roll, and one can cut to length and glue together. But this mainly used for applications where there are little/no pressure involved. With a rod seal made of a plat rubber seal, it will be difficult for any oil come in and press the gaskets radially on to the rod. Personally I would say it is a waist of time even to consider making hydraulic seals by hand, one have more than challenges enough with making grooves for standard seals, and other machined parts of a hydraulic cylinder, to tolerance. Don't misundersand, generally it is very good and important being curious all the time, being creative, learn new things, ask questions about things, how to improve things and so on.