Author Topic: Rizzo....... (Read 39012 times)

Stilldrillin · « **on:** June 09, 2011, 12:56:46 PM »

Time to start on another Orphan........

You've seen the pics of this one before. It's called “Justine's” by James G Rizzo. Published in Engineering in Miniature 2004.

Said never to have run.

Looks ok..... Been picked up too many times, by the transfer pipe. I can actually feel it blowing from the displacer joint, when the flywheel is turned.

Nil clearance at the ends of displacer 3/4" stroke. (Bump, bump, bump..... ).

Stripped.......

Everything seemed ok. Don't like the glued in, displacer and cylinder plugs.....

It needed a better support for the pipe to displacer cylinder joint. So, I opened the socket to 6mm x 10mm deep, intending to fit a recessed, extended sleeve, to support the lower end of the pipe. Which was also araldited in place, only.......

The displacer piston slid freely in the bore........ Didn't feel quite right........

The shaft slid out into my hand!!! It had let go from the displacer!!!!!

Nowt else to do, but heat it up to loosen the glue, and release the bearing end cap......

Not a lot of location area. Might have worked better if the braze hadn't been faced off......

No penetration! It had only been held on by the brazing flux.......

Oh dear...... Is this the start of another “Robinson rebuild” saga?

Sheesh!

sbwhart · « **Reply #1 on:** June 09, 2011, 01:08:24 PM »

Quote

Oh dear...... Is this the start of another “Robinson rebuild” saga?

Sheesh!

Well you sorted the Robinson out Dave I'm shure you'll sort this little Italian job and have it ticking over like a Ferrari

Looking forward to your adventures.

Stew

lordedmond · « **Reply #2 on:** June 09, 2011, 01:47:39 PM »

Looks like beauty was only skin deep in this case

the builder has ,looking at the pics made a nice job but let himself/herself down with the hidden bits

Stuart

NickG · « **Reply #3 on:** June 09, 2011, 03:47:31 PM »

Nice looking engine, was it a non runner to start with then?

stirling lad · « **Reply #4 on:** June 10, 2011, 08:21:02 PM »

the builder appears to have tried for a nice finish but seems to have cut corners on the bits that are'nt seen...show us how it should be done David..

...Mike..

Stilldrillin · « **Reply #5 on:** June 11, 2011, 10:44:33 AM »

Thanks for your comments Chaps!

Nick, I know little about it's history. Bought from Ebay by a pal, who couldn't fix it. Swapped it me for a Mamod twin.......

It arrived accompanied by scans of Engineering in Miniature build pages.

The alloy power piston looks to be, as originally machined/ polished.

To me, (so far), the problem is reliance on "Araldite" to glue parts together...... As instructed!

I'll chamfer the end of displacer shaft, to run in some silver solder..... But the other end is an alloy disc held in by some more glue!

Guess that will have to come out first.......

David D

sorveltaja · « **Reply #6 on:** June 11, 2011, 11:20:46 AM »

David, are you sure, that you have the original plans?

Anyways, to my(lacking) knowledge, too much glue is involved, when working on such a high-temperature engine. As a shortcut, glue works for a minute, until it starts to shrink, then it starts to stink.

Bogs might have more correct answer, what comes to high-temp glues, and their use on engines, like yours.

Stilldrillin · « **Reply #7 on:** June 11, 2011, 05:17:46 PM »

Tapio.
I have the original series from the magazine.

The suggestion is to produce a shrink fit, with a "bonding epoxy adhesive", in grooves around the male component.

I have much more faith in high temperature sleeve retainer.......

All affected joints will be parted and rebuilt, properly!

David D

Rob.Wilson · « **Reply #8 on:** June 12, 2011, 05:36:10 AM »

Hi David

I am sure you will have this engine licked into shape in no time

Rob

Stilldrillin · « **Reply #9 on:** June 13, 2011, 01:10:49 PM »

Thanks Rob! We'll see.......

Finally managed a little shop time this afternoon.

Dunno why the flywheel was a mm or so, eccentric. But it's ok now! Topped it, mounted on it's shaft. Friction drive off the chuck jaws.

Two grub screws down the same hole, had me fooled for a while though.......

Chamfered the displacer hole and shaft end, remembering Boggy/ Stew's ring of silver solder, tip.

Only the second time I've silver soldered anything.......

The cold end plug held ok. Must be shrink fitted.

The cleaned up components..... Made the pipe supporting socket. Faced 1/32", or so from the inner face of the cylinder plug.....

Loosely assembled......

That's enough excitement for one day.

David D

arnoldb · « **Reply #10 on:** June 13, 2011, 01:45:21 PM »

Looks great David

Watch the silver soldering; it can become addictive once you get the hang of it

, Arnold

stirling lad · « **Reply #11 on:** June 13, 2011, 03:51:34 PM »

Very neat n tidy work David, and great photos too!

looking forward to the next installment..

...Mike...

lordedmond · « **Reply #12 on:** June 14, 2011, 02:24:40 AM »

I take it the magic smoke has remained inside the motor with all this new work

Stilldrillin · « **Reply #13 on:** June 14, 2011, 02:30:50 AM »

Quote from: lordedmond on June 14, 2011, 02:24:40 AM

I take it the magic smoke has remained inside the motor with all this new work

Had that hot smell again Stuart, several times.

So, I ignored it and carried on.......

David D

sbwhart · « **Reply #14 on:** June 14, 2011, 02:42:36 AM »

Fee Fi Fo Thumb I smell another runner.

Stew

Stilldrillin · « **Reply #15 on:** June 15, 2011, 12:51:25 PM »

Quote from: sbwhart on June 14, 2011, 02:42:36 AM

Fee Fi Fo Thumb I smell another runner.

Stew

Nah! Not just yet, Stew.......

Guess that's round one to Rizzo!

Assembled, properly......

New support sleeve for the transfer pipe. Remade the cylinder head/ hexagon seal. Made a nice screw plug, with a ho ring. Sealed both ends of the pipe, into the fittings.

Attempted to run it for, 10 mins or so..... It was trying. But, not very hard.

Tomorrow, it goes into a bucket of water. To see if there are any leaks........

David D

lordedmond · « **Reply #16 on:** June 15, 2011, 01:29:44 PM »

I hope it can swim

NickG · « **Reply #17 on:** June 15, 2011, 06:21:40 PM »

the water bucket is a great test!

stirling lad · « **Reply #18 on:** June 16, 2011, 09:56:12 AM »

Quote from: lordedmond on June 15, 2011, 01:29:44 PM

I hope it can swim

I would'nt worry about that, all ugly ducklings can swim but just like this one,,they're terrible runners!

...Mike...

Stilldrillin · « **Reply #19 on:** June 17, 2011, 02:26:46 AM »

Quote from: stirling lad on June 16, 2011, 09:56:12 AM

Quote from: lordedmond on June 15, 2011, 01:29:44 PM
I hope it can swim

I would'nt worry about that, all ugly ducklings can swim but just like this one,,they're terrible runners!

...Mike...

Nice one Mike!

And so blummin true!

No leaks. Only a little fuffle from the displacer bearing.......

Wondered if it needed more inertia, cos' the flywheel's a bit lightweight.

So, I fitted a 5" casting I just happened to have handy.......

No difference at all........

Hmmmmm.........

David D

stirling lad · « **Reply #20 on:** June 17, 2011, 12:11:09 PM »

yes but it's starting to look like a very nice paper weight,,

...Mike...

sorveltaja · « **Reply #21 on:** June 17, 2011, 12:52:11 PM »

Dave, too bad you couldn't get it to run

.

I assume, that you have checked, that dimensions of parts are correct? How about their materials?

NickG · « **Reply #22 on:** June 17, 2011, 02:01:21 PM »

Dave, what is the knurled bit on top of the power cylinder for?

Looks like you'll have to go back to basics, what are the clearances radially and on the ends of travel of the displacer, also, what diameter is the displacer and power piston? You want the displacer swept volume to be significantly higher than the power piston (look at the ones on you're robinson - the difference in diameters is huge). On this type of engine (gamma I think) the only way is to have a larger diameter since the strokes are the same running off the same crank.

Then it's just a matter of friction if the leaks are sorted.

Hope this helps.

you'll get there, these things are usually temperamental!

Nick

Dean W · « **Reply #23 on:** June 18, 2011, 07:01:28 PM »

It sure is a nice looking engine, David. It will look even better when it's running!
I'm puzzled at the call for glue in the prints, especially in a heat engine. Just doesn't seem right.
I think tracking down any friction, no matter how slight, is in order. Also, be very critical of leaks,
however small they may be.
Nice looking flywheel there... ; )

Dean

Stilldrillin · « **Reply #24 on:** June 19, 2011, 05:56:00 AM »

Thanks for your comments Chaps!

Nick, the knurled thumbscrew with O ring, replaces a 6mm bolt and fibre washer. Not completely sure why they have a T junction. But it makes oiling the piston easy.....

As I reassembled, I checked it was to drawing spec.
Apart from 7/32" dia shafts, an alloy piston, and plain crank bearing, I couldn't see much wrong.......

This one, on Ebay at the moment, seems to run ok!

The stroke is 3/4" (19mm).

Piston 26mm dia.

Displacer (only?) 32mm dia.

I wonder if the oversize displacer shaft, is altering the cold end swept volume, significantly?

Anyroad!
I'm looking at reducing shaft diameters, needle/ ball bearings, new piston in a different material. Probably!

David D

NickG · « **Reply #25 on:** June 20, 2011, 05:00:02 AM »

David, it could be, it doesn't take much. Just going off the 32mm and 26mm, the ratio of volumes is only 1.5 (pretty small), as you say, when you take off the diameter of the shaft that doesn't leave much at all, especially when there is quite a bit of 'dead' space in the system. It may require a lot of heat to run? To me the design sounds marginal but you've just shown a working one (can't see it here though)

I was going to say, different piston material could be a good idea too.

Nick

Stilldrillin · « **Reply #26 on:** June 20, 2011, 05:45:24 AM »

Nick.
I have literally, just stripped it down again......

The alloy piston has a few small dings/ burrs, and is a little too tight for my liking, in the stainless cylinder. (Expansion, and all that).

Think I'll give it a polish, and chamfer the "thrust faces" of the crank bearing to reduce oil drag.

If that doesn't work, then I might start to do some alterations.......

Did anyone else see what that green one went for?

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=300567752307&ssPageName=STRK:MEWAX:IT

£226.87 !!! Sheesh!

David D

Bluechip · « **Reply #27 on:** June 20, 2011, 06:23:09 AM »

Hi Dave

Stick at it .. I'm sure the Rizzo will do a Whizzo sooner or later ...

Not sure I'd pay that price for the one on feebay ... it's a bit ugly ...

Not as ugly as me I admit, but it's running a close second ..

Dave BC

Stilldrillin · « **Reply #28 on:** June 20, 2011, 04:16:34 PM »

Gave the piston a deburr & polish. Spacered the two conrods on the crankpin. Put everything back properly, again.

Close, but no cigar! It was trying, spinning free for many revs. Always stalling on the vacuum stroke.........

So, I added more heat.......

YEEeee....... HAaarrrrrr!!!!!

Tried the lighter flywheel. No difference........

Runs only at medium/ high revs. With a lovely thumping sound. I think, due to the pressure stroke doing all the work.

Another Orphan revived!

Happy Little Drillin........

David D

Bluechip · « **Reply #29 on:** June 20, 2011, 04:42:45 PM »

There you are, you see.

I knew you'd crack it

Where's the video then ???

Dave BC

sbwhart · « **Reply #30 on:** June 20, 2011, 05:11:44 PM »

I knew you'd tame it Dave

I wonder

if there was any significance in the ebay engine running with a cowl and chimney getting more heat into the system.

Stew

Rob.Wilson · « **Reply #31 on:** June 20, 2011, 05:37:29 PM »

Just new you would get here sorted David

Rob

I

,,,,,,,, were is the video

Stilldrillin · « **Reply #32 on:** June 20, 2011, 05:54:51 PM »

Thanks Chaps!

Video? Now hang on....... It's not finished yet!

Going to fit a smaller dia displacer shaft, and see what difference that makes, if any.

Then, I've got to make a burner it will run with.

It's not all euphoria here, you know. Can't just sit back and relax, cos it's running. Have to do the whole care package.......

David D

Dean W · « **Reply #33 on:** June 20, 2011, 06:27:13 PM »

I think you've got the touch, David!

stirling lad · « **Reply #34 on:** June 21, 2011, 10:11:43 AM »

Another naughty little engine skelped into shape and set on the right road

puzzle solved.. 10/10

...Mike...

SPiN Racing · « **Reply #35 on:** June 21, 2011, 10:29:22 AM »

Very nice work giving it CPR!
Looking forward to the video!

Scott

NickG · « **Reply #36 on:** June 21, 2011, 07:15:35 PM »

David,

Nice 1, friction seems half the battle with these, my stirling with no heat on it, will move and find it's own position due only to the weight of the piston and the imbalance in the assembly - this is a floor in itself but at least proves the friction is low, balancing only seems critical on LTD engines in my experience, assuming you're just after getting a runner. I have no doubt that a smaller displacer shaft will help slightly, as would the cowl as Stew says.

Well done, you've certainly got the knack of these.

Nick

Stilldrillin · « **Reply #37 on:** June 22, 2011, 02:16:54 AM »

Thanks for all your positive comments Chaps! Much appreciated......

Didn't manage much, yesterday. But I proved sleeve retainer is much superior to the glue previously used.

Getting the assembly apart again, with the blowlamp, was a bit of a struggle. Needed much more heat........

I sawed off the displacer shaft, and "glued" a brass slug into the shaft bearing hole, ready to drill out to 4mm.

Hope to pick up again, in a day or so.

David D

Stilldrillin · « **Reply #38 on:** June 23, 2011, 12:58:43 PM »

Managed a couple of workshop sessions today.

Faced end of shaft flush. Tap drilled. Counter drilled 4mm. Tapped 1/8" Whit.........

Turned/ threaded some 4mm silver steel, to spigot 1/4" deep into original shaft.......

Screwed together,with sleeve retainer. All nicely straight/ in line.......

Bushed the shaft bearing and clevis to new size........

Assembled all parts, with sleeve retainer........

Got it all nicely assembled, and spinning freely. Bouncing off compression, when the knurled plug was fitted.........

Then, I realised me little legs had had enough....... And, tomorrow's another day......

You'll all have to wait a little longer, for the grand video! Sorry! ........ (Not really)......

David D

NickG · « **Reply #39 on:** June 23, 2011, 03:43:38 PM »

That looks a lot more sensible to me Dave

now wake up and do the video

bouncing off the compression still shows that ratio of swept volumes is small for this design - that's not a bad thing, it makes the engine more efficient but it does require more heat.

Dean W · « **Reply #40 on:** June 23, 2011, 08:54:43 PM »

How's your supply of sleeve retainer holding out, David? Looks like they have another fan of their product. : )

stirling lad · « **Reply #41 on:** June 23, 2011, 09:30:51 PM »

The tensions unbearable,,will it ?? wont it?? If It does'nt run will he have enough sleeve retainer to rebuild it again ??? so many questions

but it is looking great David,and i cant wait for the video too...

Mike...

Stilldrillin · « **Reply #42 on:** June 24, 2011, 02:16:47 AM »

Mornin' Chaps! Thanks for your comments......

Dean, the "glue" is still coming from it's tube, when requested. Wonderful stuff. Goes a long way!

There were a few days of mild panic, after I'd assembled the displacer assembly for the first time......... Couldn't find the tube in it's card!

Four days of searching, produced lots of things which I didn't know were lost!
On the fifth day, Mrs. Drillin said. Is this what you're looking for? It was under some clean washing!!

Don't ask..... I don't know either!

What a terrifying situation to be in....... NO Sleeve Retainer!

However did I manage, before that little blue tube came into my life!

David D

Bluechip · « **Reply #43 on:** June 24, 2011, 02:27:06 AM »

Dave SD

Is this the stuff ??

http://www.hogparts.co.uk/index.php?main_page=product_info&products_id=85540

Must be very wealthy around Chesterfield ??

Dave BC

Stilldrillin · « **Reply #44 on:** June 24, 2011, 03:19:42 AM »

Quote from: Bluechip on June 24, 2011, 02:27:06 AM

Dave SD

Is this the stuff ??

http://www.hogparts.co.uk/index.php?main_page=product_info&products_id=85540

Must be very wealthy around Chesterfield ??

Dave BC

Guess so........

Don't need to be wealthy Dave, when you have good friends in other places........

David D

Bluechip · « **Reply #45 on:** June 24, 2011, 03:44:30 AM »

Hi Dave SD

Ah yes ...

Er ... shall we say .... 'transparent to the system' ??

My sort of commerce ..

Dave BC

DMIOM · « **Reply #46 on:** June 24, 2011, 05:08:44 PM »

Quote from: Stilldrillin on June 24, 2011, 02:16:47 AM

.........On the fifth day, Mrs. Drillin said. Is this what you're looking for? It was under some clean washing!! ........What a terrifying situation to be in....... NO Sleeve Retainer! ......However did I manage, before that little blue tube came into my life! ......

Well, maybe the washing needed mending too? - how does it work on a Raglan sleeve?

Dave IOM

Stilldrillin · « **Reply #47 on:** June 30, 2011, 03:47:36 PM »

Quote from: DMIOM on June 24, 2011, 05:08:44 PM

Well, maybe the washing needed mending too? - how does it work on a Raglan sleeve?
Dave IOM

Nice one Dave! Never thought, Mrs D might be to blame!

Finally managed to have a heat up this afternoon, and remembered the camera too.......

This is a later video. Taken with a newer/ better camera.......

It's probably run for 2 hours or more, now.

I lube the moving parts with 5W-30 engine oil. But, the power piston gets a fuff of WD-40, as it only gets very slightly warm.

Another orphan rescued!

But, three more have arrived, since mid May.......

David D

Bernd · « **Reply #48 on:** June 30, 2011, 04:29:13 PM »

Very nice David.

Bernd

NickG · « **Reply #49 on:** June 30, 2011, 06:17:28 PM »

Nice work David, looks stunning and runs superbly now.

It's amazing how some of those little things you modded can affect the running of these engines.

Nick

Dean W · « **Reply #50 on:** June 30, 2011, 06:26:05 PM »

Runs beautifully, David. I really like the sound it makes, too.
Well done!

arnoldb · « **Reply #51 on:** June 30, 2011, 06:48:56 PM »

Great going David

- runs like a champ now

Quoting you from your video: "I'm a bit pleased with that" - So you should be! - that's the under-statement of the day

, Arnold

stirling lad · « **Reply #52 on:** June 30, 2011, 07:52:10 PM »

another excellent job!

and another successful orphan rescue

you certainly know your stuff,

when trying to whip

these little
so n so's into shape... A true master at work

Zen and the art of the stirling engine

...Mike...

sbwhart · « **Reply #53 on:** July 01, 2011, 02:46:41 AM »

And so you should be pleased

Great work

Your little orphanage must be full to over flowing

Stew

cfellows · « **Reply #54 on:** July 01, 2011, 08:33:31 AM »

What a nice running engine you have now! Some very nice rescue work there.

Chuck

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Author Topic: Rizzo....... (Read 39012 times)

lordedmond

Rob.Wilson

lordedmond

lordedmond

Rob.Wilson