How to clean inside a cylinder

[DumbStudent]

Hi. I'm thinking of planning to potentially and design a hydraulic cylinder that I may or may not end up actually making. (I'm tryna make a hydraulic cylinder). I'm going for a telescopic single acting one, and so far it's looking like there'll be a 3" x 0.25" (length TBD) 1026 MS DOM tube that another piston needs to slide in and out of.

Anyways for the cylinder itself, I'm concerned about cleaning the inside of it enough for a piston to be sliding around. I don't think my hands will fit in that. I was originally considering getting alloy steel or stainless steel, but those looked way too expensive. I also need to weld a few random things to it like the base and fittings.

Currently, my plan is to clean weld surfaces + weld + machine + whatnot, then dunk in vinegar to remove mill scale and whatnots, then stick some scotch brite or sandpaper on a stick and try to scrub the insides, then electroplate with nickel.

Please flame this plan. I have no idea what I'm doing. And if you have any tips on how to clean the inside of a MS cylinder that'd be amazing. Thanks.

 

[Kernel Sanders]

To throw out idea's and potential issues with making your own hydraulic cylinder

Distortion after welding may be an issue... out of round or taper may occur so a boring process then maybe a cylinder hone maybe?

Electroplating the inside of the bore may not be an easy thing to do as it seems
-electrolyte solution
-nickel sacrificial rod
-jigging the setup so the nickel rod is positioned in the cylinder in the solution

Sorry to say I personally wouldn't attempt it unless it were small and specialized, otherwise I'd buy one or at the most get a used one to modify.
The plus, a very learning experience! If you have the time and patience and materials go for it.

Others here may have done it, I don't know. Hope someone with way more experience can chime in

 

[DumbStudent]

Oh yeah this is just a learning thing. I don't even expect this to work. I just thought it'd be cool and I wanna add stuff to my resume. Also I'm just really proud of my spreadsheets on this lol. They're probably not even that good but idk I think they look pretty.

About welding distortion, I'm also kinda worried about that. The only confidence I have is that I've seen the fittings welded on in YouTube videos. So you know, if they can do it, surely I can hehe.

For electroplating, I was gonna dunk the entire thing in the solution. I'll be doing some tests on small samples. Just waiting on some Nickel strips to come. Again, saw a YouTube video where a guy went over it. I think it'll be doable enough for me.

I've been able to research on most things that have come up. But for the life of me, could not find anything on cleaning the inside of a cylinder. On YouTube videos, it looks like they don't even clean the inside even though it looks all rusted.

 

[whydontu]

Hot soapy water and an ultrasonic cleaner, then one if these:

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

 

[Susquatch]

They also sell flexible honing balls. Balls of abrasive stone on spring wires. You can mount them on a drill at the end of a hex shaft. The springs let them ride along without removing any more material than wanted. This is just an example. You can get the grit size and working diameter you want.

Amazon.ca

I suppose a set of very fine honing bars (the kind you use to hone an engine cylinder) might work even better. Again, get the grit size and working diameter you want for your application.

Amazon.ca

I too recommend just buying and modifying an existing hydraulic cylinder. Princess Auto sells a very wide variety.

 

[Susquatch]

Again, saw a YouTube video where a guy went over it. I think it'll be doable enough for me.

Be careful about so called experts on YouTube.

 

[DumbStudent]

and working diameter you want for your application.

Amazon.ca

Oh that looks beautiful. Thank you.

Be careful about so called experts on YouTube

Yeah. I usually read the comments sections to see if people have things to say about it, and do other research to make sure there's some consensus on the topic and methods. I guess I'm kinda lucky though since what I'm doing doesn't really matter. I'm gonna get some good practice on documentation lol.

 

[cuslog]

Well, I know you thought it'd be fun to make one from scratch, at one point, I thought the same. Then I realized that you can buy honed ID tube and the chromed rod, made specifically for this purpose. I needed a hydraulic cylinder for a specialized purpose and there was no commercially made one available. So, I bought the honed ID tube and rod and made my own piston, gland, tube ends etc. If the O-rings and seals are going to live for very long, you need that honed surface.
If you want to fool around on the cheap though and maybe learn something, I know some have been made with PVC or even ABS plastic tube, then actuated with compressed air. Careful, even 100 psi compressed air can send parts flying with surprising velocity !

 

[whydontu]

I work with three mad scientists, Mad Scientist #3 makes polyurethane fluid power cylinders that are suitable for almost any energy source. Our current test bed is a 4” bore cylinder that works smoothly with hydraulic oil, municipal potable water, compressed air, and, as long as it’s not too lumpy, whatever process fluid that’s running through the plant. Designed for 40 to 500 psig supply, we’ve demonstrated >100,000 cycles at 2200 psig operating pressure.

 

[historicalarms]

I used & abused and fixed a couple multi stage hyd hoists for a # of years, I suspect a lot bigger than your planning, mine were 4 or 5 stage 8in in dia and 30 ft long.
You will need a certai amount of honing to the inside dia of every stage you require otherwise use will quickly erode the packing. The top of every stage except the last stage will need a packing ring threaded to it to adjust packing material tightness to control leakage and pressure rquired to extend the stage.
You can easily make all the tubes & rings needed but I would recomend buying the packing from a hyd repair store....they will have everything you need I'm betting.
If you do want to go for a "home built packing material, sisal rope wrapped tightly around your stages and then tightened/crimped tighter with the packing ring will prob do the job for a short while...just retighten/adjust ring periodically when leakage is noticed.

 

[mmfw12]

Buy the honed tube. You will not be successful any other way. I had to replace the cylinder on my German cold saw. I bought the tube and new rod then machined it to fit.
It is an air over hydraulic setup and has been working fine for almost ten years.
Another option would be to find an old cylinder of the approximate diameter and then cut it up and customize it to your needs. It will have the right size piston and seals and is proven to work (hopefully).
I fully understand the need to experiment and learn but even fully equipped shops with 20 machinists buy the honed tube for cylinders. Think of it in the same way the no one smelts and rolls out their own steel flat bar to learn the process.

Good luck!

 

[FatherWes]

I’d start with a shock absorber, even a used one from an auto wrecker. Honed cylinder, polished shaft, seals on the piston, even a litre or so of nice hydraulic fluid. You’ll need to configure the inlet/outlet ports and work out the valving, but it should be a dirt cheap starting point.