One more cube fusor

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Jon Rosenstiel
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Re: One more cube fusor

Post by Jon Rosenstiel »

Wow! Very nice Finn, love what you've done with your cooling system. More than once I've sat staring at my cube trying to visualize how to configure cooling water passages similar to what you have done. Good, and very neat, work. Steampunk-ish indeed.

JonR
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Finn Hammer
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Re: One more cube fusor

Post by Finn Hammer »

A litle update on the Steampunk Dragon.

Some brass and alluminum discs arrived:
Materials for the endplugs and the manifold. Also shown are the jigs I use to drill the associated holes
Materials for the endplugs and the manifold. Also shown are the jigs I use to drill the associated holes

These materials were run across the lathe, soldered and cleaned up. Endplugs in particular need more polishing.

The manifold parts are now complete, and the endplugs just need polish.
The manifold parts are now complete, and the endplugs just need polish.

This manifold is a bit complicated to make, and I have full understanding if an 8-arm octopus style cooling arrangement will be the weapon of choice in the future.


There are now 52 helicoil inserts in the assembly:
With the work invested, I do not want to suffer the grief of a pulled out thread.
With the work invested, I do not want to suffer the grief of a pulled out thread.

So anyway, here it is, in the first test assembly:
The Steampunk Dragon first test assembly.
The Steampunk Dragon first test assembly.
That's it for now, still a long way to go before first plasma, however, I have just now taken delivery of a rod of EDM carbon stock for the Coulter style lens.

Cheers, Finn Hammer
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Jim Kovalchick
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Re: One more cube fusor

Post by Jim Kovalchick »

Just premier work!
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Mark Rowley
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Re: One more cube fusor

Post by Mark Rowley »

Beautiful work Finn.

In more ways than one, yours will be the coolest fusor around!

Mark Rowley
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Richard Hull
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Re: One more cube fusor

Post by Richard Hull »

Just wow!

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Finn Hammer
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Re: One more cube fusor

Post by Finn Hammer »

Just an update on progress.

Drawings are needed to support the image of the Fusor assembly, that I have in my brain. They start with scribblings, like this one here, where the main lines are lay'd out, believe me, even though it may not be at all obvious.


Scribbled attempt to hold on to a vision.
Scribbled attempt to hold on to a vision.

And it is also my own problems reading the drawing, and the tedium of redrawing it over and over to put more parts into it that
at this point I finally realised, that there is only one way, lad. And that is CAD.

The challenge of drawing the individual components looked overwhelming to start, but soon the resulting view into what becomes a clean and simple layout, proves that the effort is well spent. The occation to learn more techniques within the CAD package is an added bonus, I got better at mating parts, and the bent bellow tube is my pride. And a part drawn in CAD can be used over and over.....


Nice clean view of components.
Nice clean view of components.

Cad rocks!
Cad rocks!

The core structure is a 901P monitoring the foreline, just before the Pfeiffer TMH 071 P turbo. This one gets throttled into KF25 (the joy of having a lathe, now) and routed to a MKS bellows throttle/isolating valve and enters a cross which feeds into the fusor, a 50 micron Baratron and a 999 Quattro pressure transducer, which both are thus kept out of the line of plasma, and the transducers and the fusor are equally distanced to the center of the cross, which ought to facilitate accurate measurements. The Quattro can measure higher vacuums than the Baratron, so that one is for determining base pressure before filling with Deuterium,(and for zeroing the Baratron) monitoring of plasma pressure is reserved for the Baratron.
The Deuterium flow will be controlled by a 10 CCM mass flow controller, preceded by a Sigma Aldrich pressure gas regulator. Ahead of that is the precious lecture bottle, not yet shown.

Great satisfaction at the CAD package is had!

I ordered a lead glass viewport from Lesker, and there will also be sacrifical quartz glass disks inside the fusor, probably also a screen.

Speaking of Quartz glass, a week ago I did not know anything about it, now I am in love! Fantastic stuff, I have ordered lengths of it in 19/25 dia and in lengths of 100, 150, 200, 250, 300 mm. It is my intension to do a piece of research into the needed length of tubing in the do-it-yourself feedthroughs that I see, originating from Coultier, Selzman, David. I will apply field controll to the best of my knowledge, but that is for the second iteration.

Getting to know about new materials and new techniques is the core of the Fusor effort satisfaction

Cheers, Finn Hammer
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Richard Hull
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Re: One more cube fusor

Post by Richard Hull »

I have always pushed for proper predesign setup planning on fusor systems, especially as relates to spaces being too tight for easy servicing or even convenient initial assembly and subsequence disassembly in repair or replacement situations. Try and get a wrench to tighten or loosen a conflat bolt with an ill designed work space around it. Try and fight putting on a KF fitting clamp that can't easily fit around the couplings that are against a wall or a plate. It is a design challenge and jungle out there in an attempt to think of everything that seems so simply mechanical until you screw up having worked so well on keeping it all compact, neat and tidy..

Nice that you are noodling it all out before hand.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Finn Hammer
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Re: One more cube fusor

Post by Finn Hammer »

Things are starting to come together, and I need to ask a question about mounting the turbo.
latestcube.JPG
Sideways, and with the inlet pointing down (since I am using a rotary vane pump) is as recommended in the manual, but there seems to be some reservations on the side of Pfeiffer, regarding the rigid mounting of the pump on the far side of it. Far side being opposite of the inlet.

Pfeiffer seems to favour mounting the pump from the high vacuum side, by attaching the big flange to the chamber, and they have some limits to the forces that can be excerted to the pump.

My approach is to fix the bottom of the pump, and be gentle with it on the high vacuum side, by using a bellows pipe right next to it.
mockup.jpg
I am asking if this looks right, since now is the last chance to change it.


Cheers, Finn Hammer
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Jim Kovalchick
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Re: One more cube fusor

Post by Jim Kovalchick »

Finn,
My turbo experience is with a Leybold not Pfeiffer, but mine is a similar size. I started using a horizontal alignment recently after always using vertical in the past. I use a bellows right angle valve before the turbo. So, there is a right angle. I also have a KF 40 sized instrument pipe before that. It's not optimum but it works.
As far as vibration, your mount is more important than your incoming line. My biggest source of vibration is the roughing pump. I use a flexible steel bellows pipe on that side. I use a foam pad beneath the turbo to muffle the vibes.
My experience is also that the smaller turbos are fairly tolerant of abuse.

Good luck.

Jim K
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Finn Hammer
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Re: One more cube fusor

Post by Finn Hammer »

Thanks, Jim

On second thought, the frame as it is, is awfully wiggly. I probably better finish it up as a full "aquarium" frame, and add corner gussets, to make it rigid and stiff.
perhaps also double that corner post up on the other side of the turbo, to support the bracket on both sides of the turbo.

Speculating about which way to mount the turbo, I visionalised these two alternatives:
turbowiggle.jpg
If these modes of wiggle hold water, then sure, it would be better to mount it by the throat. The turbo end of the pump is mounted in a magnetic bearing, which allows the rotor to find and rotate around its own center of gravity, which may not be the same as the shaft centerline. I have a feeling that too much wiggle there could cause a crash. But if the mount is rigid enough, then mounting it at the bottom should work as well. Actually, there should not be much vibration at all.
Time to order more extrusions.

Cheers, Finn Hammer
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Richard Hull
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Re: One more cube fusor

Post by Richard Hull »

I had no direct experience with turbos until Fusor V, but do have experience with gyroscopes of some size. I bolted the living hell out of my little turbo to the rigid fusor table which is bolted to the wall of the building with the side wall bolted into the concrete floor with poured molten lead anchor bolts. Certainly over kill, but I don't worry about the turbo torqueing around.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Finn Hammer
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Re: One more cube fusor

Post by Finn Hammer »

All,

After I realized that the frame had to be closed on all sides, and a additional post for the other side of the turbo, everything got rock solid, and the turbo spins up without any problems.
firstlook.jpg
I will move over to Images du Jour from now on, since things are getting very basic.

Cheers, Finn Hammer
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