V4 Wobbler - double acting - magnetically held (no springs)
2D ACAD *.dwg & *.dxf plus *.doc build notes
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View attachment V4WOBBLE.zip
2D ACAD *.dwg & *.dxf plus *.doc build notes
?
View attachment V4WOBBLE.zip
V4 Oscillator Motor
- Thread starter Ken I
- Start date
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Richard Hed
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Do you have a movie of this running?
Richard, I added it to my response to your thread - you were too quick we've crossed.
Regards, Ken
Regards, Ken
Richard Hed
Well-Known Member
- Joined
- Nov 23, 2018
- Messages
- 2,380
- Reaction score
- 615
I'll have to study that more closely at a later date. Thanx for the .dwg.
Nice to see another sweet little model. I am curious to know how much pressure it takes before the magnets are overcome by the air pressure at the inlet ports? - That being the limiting factor (as I understand?) for oscillators? I think the full sized oscillators used shaft porting and sealed better that way with higher pressure steam, without being so prone to "inlet valve leaks? - But I have never heard of anyone using "magnetic" sealing before - so well done!!! I am curious to know your magnet arrangement - if you have a schematic?
Thanks,
K2
Thanks,
K2
Richard, This is how the magnet sits between the cylinder trunnions.
The magnet is a press fit in the bronze bush and the trunnions - which the cylinders oscillate on within the bush - are almost touching the magnets.
This provides a surprisingly large hold down force - I had to skim the trunnions back from 0.1mm clearance to 0.5mm clearance as they were too strong.
So its simple to adjust the "spring".
The magnets a 8mm diameter x 5mm long - available from any magnet supplier.
Regards, Ken
The magnet is a press fit in the bronze bush and the trunnions - which the cylinders oscillate on within the bush - are almost touching the magnets.
This provides a surprisingly large hold down force - I had to skim the trunnions back from 0.1mm clearance to 0.5mm clearance as they were too strong.
So its simple to adjust the "spring".
The magnets a 8mm diameter x 5mm long - available from any magnet supplier.
Regards, Ken
Excellent design! - Love it! - I have a Single acting twin - with a pair of external springs - needs lots of attention as the bores and crank are well worn. But while I'm doing that, it may get the Magnetic conversion!
Will your engine take 20~30psi? - My engine is to run on steam and drive a generator...?
K2
Will your engine take 20~30psi? - My engine is to run on steam and drive a generator...?
K2
I don't know why but I never made a video of the single cylinder version - so here it is :-
The poor thing hasn't been run in 2 years.
I open the voiceover stating it to be a single acting - I meant to say a single cylinder version of my V4.
The magnet is capable of outperforming a spring - I run it at 100 psi in the video - I have under test previously run it at 120 psi.
This motor is entirely metal to metal - there is no rod gland or piston ring.
Regards, Ken
The poor thing hasn't been run in 2 years.
I open the voiceover stating it to be a single acting - I meant to say a single cylinder version of my V4.
The magnet is capable of outperforming a spring - I run it at 100 psi in the video - I have under test previously run it at 120 psi.
This motor is entirely metal to metal - there is no rod gland or piston ring.
Regards, Ken
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Both of these are very cool! Love it!
Other than the number of parts, is there any reason the V-4 is more challenging to a noob than the single?
Other than the number of parts, is there any reason the V-4 is more challenging to a noob than the single?
The V4 is a little more challenging because of the complex of Ø2.0 & Ø2.5 deep drilled holes - requires a long series drill and careful planning and care at the intersects - if you break a drill off down there you are going to be in trouble - the build notes cover this.
Making 4 sets of cylinder parts is not that much work as you go into "production" mode.
Drill the deepest holes first and all the "breakthrough" holes on the shorter legs. Use a Vernier stop at the breakthrough to stop "snatching".
The V4 drawings have a version (above) without the "afterthought" throttle parked on top - designed into the body - in the middle of the "V"
Regards, Ken
Making 4 sets of cylinder parts is not that much work as you go into "production" mode.
Drill the deepest holes first and all the "breakthrough" holes on the shorter legs. Use a Vernier stop at the breakthrough to stop "snatching".
The V4 drawings have a version (above) without the "afterthought" throttle parked on top - designed into the body - in the middle of the "V"
Regards, Ken
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Ken,
Thank you. One other question--what would be the effect on operation if the holes were a bit larger diameter? I'm mostly set up for imperial drills, especially my longer drills, although I don't think I have a 2.5" long #39 drill so may need to order a couple specially for this project.
Evan
The holes sizes are not critical - however the Ø2.0 porting holes in the face of the cylinders and block will eventually overlap at Ø2.74 so a Ø3/32" would still be fine.
A quick look at the drawing tells me you can go up to 25% bigger without problems.
Feel free to check with me on any aspect if you do go ahead.
Regards, Ken
A quick look at the drawing tells me you can go up to 25% bigger without problems.
Feel free to check with me on any aspect if you do go ahead.
Regards, Ken
Thanks!
Ken, that is cute and if fun to watch, great workmanship there, would it be possible to get that drawing in a PDF, I would surely appreciate it, love your work, thanks for sharing, Joe
Lathe Nut - attached - dirty great big A0 sheet
Regards, Ken
Regards, Ken
John, I posted these plans 8 years ago - and suddenly - nothing happened !
But since Richard's query has come to the fore again.
The zip file (post #1) contains all the ACAD dwg & dxf files + build notes
Regards, Ken
But since Richard's query has come to the fore again.
The zip file (post #1) contains all the ACAD dwg & dxf files + build notes
Regards, Ken
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I've started looking for material and am getting sticker shock for aluminum bronze and other copper-containing alloys. I've found Al-bronze at 5/8 for a reasonable price on eBay, but the larger 7/8" stock needed for the plans seem quite a bit more expensive. If I have to spend $50 for stock, would Al-Si-bronze work as it machines easier than straight Al-bronze I think?
