A Tiny Tabletop Hydraulic press. Part I, prototyping the pump.
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- Опубліковано 28 сер 2023
- The many videos about hydraulic presses on UA-cam can be divided into:
- Proof of concept or toy small presses made out of PVC tubing and so, with no practical use
- Large plump heavy presses based on a car jack, very usable but way too big for me.
Here the start of my attempt to build a 1 to 2 metric tons tiny precision hydraulic table top press with a tiny electric pump. I expect the next 3, maybe 4 videos will also be about this topic.
Please inform me regarding what you think of this new synthetic voice, thank you!
Music:
Mozart piano sonata no 13 (copyright free)
LesFM (Chosic) Calm and Peaceful - Наука та технологія
Always a pleasure watching you set up a new design, Michel. Looking forward to your next video!
I've got to say, only for myself, that your approach to working metal, machines and engineering are so refreshing that I had to view, and review. every video. The voice over top it off like icing to the marvelous cake; not alot of icing (voice over) but just enough. Cheers. 👍
Thank you!
@@Michel-Uphoff 👍
Michel, very nice work on your "proof of concept" model, Congrats!!
I'm looking forward to seeing the next stage.
Thank you Colin 😊
The voice is better
I think the x-axis gibs are loose on the mill. Look at ~20:00 and on. When you drill the right hole, and ream it, either the camera perspective shakes or the vise shakes. It’s quite noticeable, whatever it is.
Kudos to you for the fantastic educational video. Thank you kindly, sir.
Thanks for the compliments!
There is nothing wrong with the gibs. The mill is standing on rubber feet, and the camera on a tripod on the floor. The whole mill moves a little when I crank it up fast.
Looks really good, always excited for your videos
Looking forward to this project. We shared this video on our homemade tools forum this week 😎
Thanks for sharing
Thank you - excellent video and very inspiring! Waiting for the next one!
I have the raw material and rough design for something very similar! You have inspired me to get those together and start work on it. My idea is made mainly from aluminium, but with replacable wear sleeves (currently stainless on the pistons). I also want to have an adjustable swash plate - but we shall see. Even my spreadsheet for estimating motor power is very similar to yours!
cool!
What were your reasons for doing a swashplate compared to a 2-cylinder crank design? Can't wait to see the result!
Two main reasons:
With a double crankshaft, such as in a boxer engine, I certainly also achieve higher efficiency.
But the design is more complex, 4 bearings needed, more moving parts.
Moreover, the motor will then have to be placed perpendicular to the pump, while the motor and the pump are in line in this design.
That's an advantage, now I can combine motor, pump, oil reservoir and column in one design part. I'm hoping that this works out as expected, because it could be a new and elegant solution.
I am assuming your final build will be of a design where the pump is enclosed in the reservoir housing, so leakage from the pumping elements will simply return to tank via gravity and no case drain plumbing will be required. I am also assuming you are building this just because you can and want to learn something along the way? Nevertheless I like the concept.
I do not know the reason why you use the synthetic voice, however the one you used today is not unpleasant. Cheers
Your assumptions are mostly correct. Part of it is the fun of inventing and building. However, I will use this press. One of the reasons for this is that I have a number of shafts that need to be straightened, they have a very slight curvature after hardening and tempering. With my current hand press I have too little control over the force I exert, and sometimes I bend a bit too far. With the design I have in mind (see sketch in the video) I think I will get that control.
I am Dutch. My written English is passable, but hearing me speak English will make you very sad. I myself sometimes get annoyed by the many videos without subtitles in which English is spoken so poorly that I do not understand most of it. With this synthetic voice I want to spare my viewers that misery.
Great video. I find transmission fluid to work better than hydraulic fuild in small hydraulic pumps. What are your thoughts?
I really don't know yet but if I give it some thought, It's less viscous:
Hydraulic at 20C 120-300 mpas
Transmission fluid at 20C 70 mpas
So it seems logical to me that the latter flows better through the tiny openings in such a small system (And is more prone to leakage).
So the benifits are canceled?
@@D3rron08 Depends I think. Such a fluid could cause problems when there are micro leaks.
When I get to the stage where I'm going to test the sealing of the system, I'm definitely going to do some testing with thick and thin oils.
I wanted to mention an improvement to your pump that you might consider. Have you thought about an o-ring to improve the seal?
Good comment!
Yes, I thought about that, but I decided against it. As you can see in the video, a drop of oil falls back into the reservoir on average every 12 seconds. In that time the pump has completed 50 strokes of 500 mm³. The volume of a drop is approximately 50 mm³, which is only 0.2 percent compared to the flow rate of 25,000 mm³. Under higher pressure this will be more, but still so little that I will not take any extra measures. In addition, 100 bar is also the maximum for a simple seal with a hard O-ring and at this pressure it causes a significant amount of extra friction. I will not be bothered by the leak in the final pump, because there too the leaked oil falls back into the reservoir.
There will be O-rings, but for closing the pump housing to the outside world. See the sketch in the follow-up video.
@Michel-Uphoff
Very good. The suggestion comes from watching industrial rebuilds of large hydraulic calendars. You know best. Thanks for the reply.
BTW: You need another axial bearing to prevent the swashplate rotating around the pistons - my guess...
I only need one thrust bearing to absorb the axial forces on the motor shaft. Between the plungers that have a rounded head and the rotating swash plate there will be a small bronze disc, on the side of the swash plate flat and on the side of the plunger with a cavity in which the plunger head fits.
mm interesting project, i want such a thing too. I'd avoid useing diamond paste on somthing like this, you will never get the diamond out of it and it will forever be grinding it's self down. there are polishes for lapping these sorts of things that are designed to break down and stop being abrasive.
I think I got the diamond paste out well enough by emerging the housing in petrol a few times brushing it thoroughly and blowing the petrol out with compressed air. I did this outside, so there is no footage of it.
@@Michel-Uphoff it will still be there, like toast crumbs stuck in a slab of butter. it may just not matter of course, depending how much use it gets.
@@Sigmatechnica So you're saying I've pressed diamond grains into the mild steel so they won't come off no matter what I do.
That should then also apply to the tool I used for it. I'll put that under the microscope.
@@Michel-Uphoff Yes. You used a ballbearing for the tool though which is going to be *hard* so will have less pressed into it than the mild steel. still it would be interesting to inspect under the microscope. in fact in this situation one might expect that the mild steel was actualy the lap taking on the abrasive, and the ball got abraded to fit, counterintuitivly. if i had any diamond abrasive i'd conduct some experaments with mild steel and a ballbearing now!
@@Sigmatechnica I've looked into it, and I think you're right. The hardened ball clearly shows a ring of abraded material under the microscope, more than I expected, like it is lapped. Can't find diamond particle however in this hardened ball, which shouldn't surprise. If I find time I will cut open the housing to view the valve seats under the microscope. If that yields interesting material, I'll come back to it in the next video. I will use copper next time.
A question, did you chose this kind of pump on purpose instead of gear pump (like in tractor hidraulic systems). I feel like geares pump would have lower form factor.
I considered a gear pump, but there were some disadvantages for the planned precision pump.
Dosing the precise amount of oil in the pressing cylinder is difficult with a gear pump.
With a plunger pump I can add one or even half a turn (roughly 0.5 cm³) and thus press the cylinder down accurately to tenths of a millimeter.
The valves in this plunger pump close automatically, and so the pressure in the cylinder remains at the same level.
With a gear pump I have to add valves.
This pump can be built easily and reliably with modest equipment (a milling machine and a lathe).
I didn't have to buy gear cutters for it.
@@Michel-Uphoff that makes a lot of sense - thank you :)
I am puzzled as to why you do not purchase a 2 ton mechanical arbor press. They are better in many ways for the sizes of work you are doing. And simple. You could even make one. Just thinking. 25mm plate laser cut into a C frame and a base and a machined rack and gear. Better a large ratchet handle and you have a very fine press. Just thinking Michel.
Mark
I think this one is as much about the journey as the destination brother
Hi Mark,
Actually, I have a small hand press. You can see it now and then in my previous videos. A simple thingie that I put together in two hours. One of the weaker aspects of this press is that I usually have no idea how much pressure I actually exert with it. It does what it's supposed to do, but with limitations, so I want a better one. Of course I can buy something, but for the tiny dimensions I'm looking for, you only end up with extremely expensive laboratory / toolroom equipment.
And besides the money, what's the fun in buying something if there is so much challenge and inspiration to be found in the construction according to a, hopefully, special design? The construction of such a simple tool as I have now is not worth a UA-cam video. So @LordOfTamarac is right, it's also the journey 🙂
Interesting approach/project. Looking forward to see how it is going to work out ... Greetings from Germany, Stefan.