Sealing Hydraulic Cylinders?

[ihbuilder]

Originally Posted by rockNmayhem

Joe, that piston is aluminum as thats what I had available. I will look at some stainless polished rod that hopefully has a better finish and I can try making that work as well.

My main thing is, how is the front of the ram sealed. Whether it be an o-ring or actual U-cup seal? Thats about the biggest obstical I'm having to over come.

Thanks for the information though.

Tyler

Tyler , on a real 1 : O-rings with backup rings and a wiper seal . For what we do just an o-ring . Real 1's use chrome rods (polished) thats what you want to have . I use 304 L ss from online metals . From the mill it comes very smooth . Another issue could be your piston seals are too tight . Looking at you ram pics , def. too course . I should note , if your cap (gland) is cocked in the slightest way that will make it leak also .

[rockNmayhem]

Originally Posted by ihbuilder

Tyler , on a real 1 : O-rings with backup rings and a wiper seal . For what we do just an o-ring . Real 1's use chrome rods (polished) thats what you want to have . I use 304 L ss from online metals . From the mill it comes very smooth . Another issue could be your piston seals are too tight . Looking at you ram pics , def. too course . I should note , if your cap (gland) is cocked in the slightest way that will make it leak also .

Steve thankyou for the metal link. I'm glad I now have a metal number to go off of. I know how to rebuild a larger cylinder no problem with all the seals and rings but for this size I figured a sealing o-ring and a wiper was all I needed but I will back it down to one.

Do you also think I can still use the U-cup seals in the front or should I just stick with cutting an o-ring grove in the cap and leave it at that?

Also do you thread your caps on? I had the first ones pressed on but I'm designing another ram where the caps thread on with 12mm x 1.25 threads and am thinnking that might help some with sealing them up and keeping them straight.

Lemme know if there's anything else I can do differently as this is kicking my rear trying to get these cylinders built.

Thanks,
Tyler

[ihbuilder]

use an x ring IOW , the profile will look like an x instead of O I get them off McM. thats what they're called . yes my glands are threaded . Next 1's will bolt like Ari's . If I where you , I'd ditch the Alum. all together and go brass . much easier to work with for making cylinders . It hones nicer you can buy the tube (seamless) make the ends and silver solder them together . What grade alum are you using ? If your going to stay with alum. use 6061-T65 or 7075 - ? (Slipped my mind ) . you get a much better finish then hardware grade crap .

[dirtpusher9]

Tyler, you may be seeping by on the tubing side you may want to hone it and cross hatch it a little if it is too smooth.

I have some pics on my dozer thread page 8 or 9 that shows how I built my cylinders that may help with design.

[Newcastle]

Originally Posted by ihbuilder

use an x ring IOW , the profile will look like an x instead of O I get them off McM. thats what they're called . yes my glands are threaded . Next 1's will bolt like Ari's . If I where you , I'd ditch the Alum. all together and go brass . much easier to work with for making cylinders . It hones nicer you can buy the tube (seamless) make the ends and silver solder them together . What grade alum are you using ? If your going to stay with alum. use 6061-T65 or 7075 - ? (Slipped my mind ) . you get a much better finish then hardware grade crap .

Do you have a website for McM. I'm interested in these seals. Thanks.

[ihbuilder]

Originally Posted by Newcastle

Do you have a website for McM. I'm interested in these seals. Thanks.

www.mcmaster.com