MadModder
Gallery, Projects and General => Project Logs => Topic started by: Stilldrillin on March 29, 2013, 06:36:03 PM
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After almost a couple of years delay. I've made a tentative start, on completing my Robinson engine rebuild.
Shop time is still very limited. But, I'll post whenever there's some progress.
Here's the original saga. Just getting the engine to the condition I hoped it would be in, when it arrived...... http://madmodder.net/index.php/topic,3555.0.html
The flywheel casting halves are eccentric to each other, and the bosses have been machined true to the opposing sides! :scratch:
Turned away as much of the balance weight as I could.......
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030269_zps49c85653.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030269_zps49c85653.jpg.html)
The engine has been dropped, and one foot is broken.
Milled away the ragged edge......
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030271_zpsb54da12b.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030271_zpsb54da12b.jpg.html)
And made a cast iron block to fit in the recess........
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030277_zps833cec94.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030277_zps833cec94.jpg.html)
I've had little practice at silver soldering. But, never (yet) had a failed joint.
What's the best sequence to use, for a sound joint in this situation? Should I flatten the wire, and lay between the parts?
Any tips would be much appreciated.
David D
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Stilldrillin, the main thing to try to do is not crack the casting. Too much localized heat and too rapid cooling can cause cracks. I would have a bucket of wood ashes nearby to plunge the part into and let cool for half a day. But I have a wood stove, don't know whether you do.
Parts must be absolutely clean in joint -- no fingerprints. flux parts. Clamp parts or wire them so they can't move. If a joint is close, but not absolutely closed. I'd feed from the outside -- the braze will wick in usually.
When heating the part. play the flame over a large area, to heat gradually instead of too localized, Gradually focus down onto your braze area.
Both parts need to be equally hot, so spend more time on the more massive piece.
When flux boils from the metal heat (not the flame) usually it's time to apply silver braze. Braze should melt from contact with the hot metal rather than just the torch. If the metal is too cool, the braze will ball up in the torch flame instead of flow onto the metal. Hold the flame on the metal just long enough to get good flow but no so long that it flows off the piece or overheats it.
You can back the joint with aluminum sheet if you think solder will flow through and drip out.
That's about all the tips I can think of.
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Good luck David! :thumbup:
Talk about a steep learning curve!
All sound advise above from all the things I've heard in the past....
Still makes it no easy task in reality... If you have any spare stuff I'd suggest a practice run.
The wiring together works for me too.... Worked well recently on my rocket.
I might thin that new part down a bit too... Much less to remove once the shape is all big and awkward to hold/machine.
Ralph.
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VT.
No wood ashes here....... Central heating, powered by natural gas condensing boiler.
Thanks for the run through.
Just the usual common sense set up, and procedure. Allied with careful heating. :thumbup:
I just wondered if c/i needed any special treatment. Thanks for the alloy sheet tip!
Ralph.
Thanks for your sympathy! No spare stuff...... Especially castings!
Yes! the block can be reduced a little at one end, as the joint face is tapered.
Thanks, both, for the support. Just needed a slight confidence boost, having only done 3 or 4 conventional joints previously........ :scratch:
Win, or loose...... Pics will be shown!
David D
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Well.....
When I'd dropped the insert on the floor, for the third time, while trying to wire it into place. I realised, it was April 1st.... :bang:
Finally got it fixed, with flux more or less where I wanted it, and positioned on a fire brick.
After some time of heating, I realised my blowlamp was ok for copper plumbing. But, well underpowered for this job! :palm:
The flux was bubbling, but no sign of any red heat! :(
Only thing to do was dab and hope.........
The solder slowly melted, and puddled. So, I dabbed some more. Hoping it might flow through. (http://freesmileyface.net/smiley/confused/sorry-3.gif) (http://freesmileyface.net/free-confused-smileys.html)
Then I went for me lunch, leaving it to cool........
(http://i110.photobucket.com/albums/n95/Dayjo/P1030282_zps6f1bcdb1.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030282_zps6f1bcdb1.jpg.html)
Turned it over, a couple of hours later. Not too bad........
(http://i110.photobucket.com/albums/n95/Dayjo/P1030283_zpse2cbe438.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030283_zpse2cbe438.jpg.html)
Milled off excess. Expecting it to come unstuck.
Why do we always go that one thou too deep? :palm:
(http://i110.photobucket.com/albums/n95/Dayjo/P1030286_zps175491f4.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030286_zps175491f4.jpg.html)
Still attached. Looking ok.........
(http://i110.photobucket.com/albums/n95/Dayjo/P1030293_zps6a990341.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030293_zps6a990341.jpg.html)
Rolled it over. Angle grindered and drilled 5mm........
(http://i110.photobucket.com/albums/n95/Dayjo/P1030294_zps1299c072.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030294_zps1299c072.jpg.html)
A couple of dabs of filler and some paint, should look ok! :D
Thanks for the support Chaps. Much appreciated! :thumbup:
David D
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Looks Good!! :headbang:
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Very nice fix. Once again, without a doubt, you have sown you are a master at rebuilding/reconditioning/re-engineering hopeless cases!
Well done.
Eric
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VT.
Thank you! :thumbup:
Eric.
Thanks! I don't know about being any sort of, Master Bodger. :bugeye:
But, I must say, I feel much more confident with the varied techniques needed. Compared to 4 years ago, when I joined Modder. :)
David D
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Good fix Dave
It's good to see you back on the case :thumbup:
Stew
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Thanks Stew!
It's a good feeling.
Not out of the woods, yet. But gentle progression, at last....... :thumbup:
David D.
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Here you may find this interesting about silver soldering
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Job well done David :thumbup:
Knew it'd be fine :scratch: :)
Now just a little bit of tweak and assembly :bugeye:
Ralph.
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well dun
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Thanks for the vid. Tom!
Love how he allows the solder to take it's own time, to flow around the joint.
Ralph, Bob. Thanks!
Tweaking is ongoing, slowly, as weather and other commitments allow. :thumbup:
David D
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I have never tried silver soldering cast iron, mainly because I've never needed to, so I have found this post very interesting. The foot has turned out well.
Neat job Cheers David
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Good to see your getting some shop time David :thumbup:
Very nice repair job on the casting :clap: :clap: :clap: :clap: good as new :dremel:
Rob
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David, Rob......
Thank You! :thumbup:
David D
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All stripped again......
(http://i110.photobucket.com/albums/n95/Dayjo/P1030305_zps1c6654dc.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030305_zps1c6654dc.jpg.html)
Looks better than the first stripdown! :thumbup:
Starting to clean parts, and adjust them to fit each other properly. Never seen a drawing, so I'm building blind. :scratch:
I used Bluecol top up mixture for coolant.
There is rust in the nooks and crannies, despite piping air through the engine for 3 days, after running. Would machine coolant mix be kinder?
What do others use?
David D
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Made a little headway.
Spent a lot of time filing and fitting together. Cleaning out threaded holes, and shortening new screws to fit.
Painted some parts........
(http://i110.photobucket.com/albums/n95/Dayjo/P1030308_zpsee3209cc.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030308_zpsee3209cc.jpg.html)
Not happy with the deck surfaces. So, will scrape off, and re paint. :(
Didn't like the pifflin' 3/16"dia. m/s crankshaft, holding a 4.5" dia. cast iron flywheel. :scratch:
So, I replaced with 6mm silver steel, and new bushes......
(http://i110.photobucket.com/albums/n95/Dayjo/P1030312_zps9ed4b0e4.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030312_zps9ed4b0e4.jpg.html)
In real life, these engines were usually located in the scullery, to supply water from the well, to an in house storage tank.
Does anyone know what kind of pump would be used?
David D
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Well you did ask,A WATER PUMP :D :D
OK I will go quietly
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Sigh....... :palm:
Thanks Frazer! (http://serve.mysmiley.net/rolleye/rolleye.gif) (http://www.blueislandsdiving.com)
David D
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Took a photo of a page -- hope it's clear enough.
(http://i786.photobucket.com/albums/yy150/vtsr/vtsr/TecumsehBuild/RobinsonPump.jpg) (http://s786.photobucket.com/user/vtsr/media/vtsr/TecumsehBuild/RobinsonPump.jpg.html)
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WOW!! :bugeye:
Thank you for the research VT. (http://freesmileyface.net/smiley/respect/respect-061.gif) (http://freesmileyface.net)
I thought the originals must have been supplied as a pump unit. But I have only ever come across solo engines. Never coupled to anything. :scratch:
David D
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Slow, but steady progress. :thumbup:
I've sleeved the flywheel bosses back to a sensible diameter. Also, the bore to 6mm.
The colour's not as orange, as it seems here........
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030317_zps36906e6a.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030317_zps36906e6a.jpg.html)
Lit a small burner, to cook the paint a little.....
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030324_zpsdc4bd30b.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030324_zpsdc4bd30b.jpg.html)
Warmed gently, for 5 mins or so........
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030319_zps9182361a.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030319_zps9182361a.jpg.html)
Didn't want any paint blisters....... But it's a trier......
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030322_zpsf7d34595.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030322_zpsf7d34595.jpg.html)
Finally coming together! :D
David D
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Looking wonderful!! :clap:
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very well dun
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Looking good
see you Saturday
cheers
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Very nice :clap: :clap: :clap: :clap: :clap:
Cheers
Abraham
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Thanks Chaps!
Today's temporary trial. No coolant. Borrowed the gas burner from the Huxtable.
Oh..... Happy Day!!!! :ddb: :ddb:
Now needs a coolant tank, and it's own gas heating system.
I've ordered a gas tank. Will have a go at making my own burner. :thumbup:
David D
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Terrific! Mrs Robinson seems to have had the full Botox since your first photos of the raddled old jade here http://madmodder.net/index.php/topic,3555.0.html
:clap: :clap: :clap:
Andy
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Thanks Andy!
Scrubbed up well, hasn't she! :thumbup:
David D
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Great to see it running, Stilldrillin! Makes me want to build one just to see it run. It's a really nice size, too. Substantial looking. Great job! :clap:
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Here's to you Mrs Robinson :beer: :) (Can't believe no one else used that!?)
Wonderfully quiet :med:
Loverly lil runner :thumbup:
Ralph.
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Spot on :thumbup:
Stew
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Thanks Fellas! :thumbup:
Stillsmilin'. (http://freesmileyface.net/smiley/happy/happy-005.gif) (http://freesmileyface.net/free-happy-smileys.html)
David D
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I've started work on the gas burner. :thumbup:
Machined the jet area, as a mixed copy of my Bix burner, and the Scott engine plans......
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030350_zpsd77e3694.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030350_zpsd77e3694.jpg.html)
Another section of Russian vacuum cleaner pipe, and offcut of mini lathe guard.
Think I'm getting the hang of this silver soldering now........
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030352_zpsab7b7217.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030352_zpsab7b7217.jpg.html)
Topped a brass disc to 1.400"......
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030354_zps498d5494.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030354_zps498d5494.jpg.html)
And perforated........
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030357_zps2f77baa4.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030357_zps2f77baa4.jpg.html)
Group shot, as of this eve.......
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030358_zps922aef0b.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030358_zps922aef0b.jpg.html)
I'll make tubular spacer/ shelf, to hold the brass disc in place. Just inside the top of the pot.
Well..... That's the outside "done". What goes inside?
I intend to span the full internal diameter, with the inlet pipe. With outlet holes, or a slot, facing downwards.
Bouncing the gas off the floor, to fill the chamber more evenly. Maybe! ? :scratch:
Anyone got any better internal ideas?
David D
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Cracking David :bow: :bow: :bow: :bow: sweet running engine :clap: :clap: :clap:
Rob
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well dun :thumbup:
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Rob, Bob.
Thank you! :thumbup:
All bein' well, today's the day to assemble and try the burner......
(http://i110.photobucket.com/albums/n95/Dayjo/P1030362_zps202d2ff0.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030362_zps202d2ff0.jpg.html)
Should I warn the Fire Brigade? :)
David D
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I am not worried ,,,,,,,,,,,,,,, your miles away from me David :lol: :lol: :lol:
Sure you will be fine ,,,,,,,,,,,, but if on the off chance you do burn your eyebrows off , get your lass to take a photo :D
Rob
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Eyebrows still intact Rob! :)
It all went very well, considering. :thumbup:
Sensible maximum........
(http://i110.photobucket.com/albums/n95/Dayjo/P1030372_zps53a880ce.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030372_zps53a880ce.jpg.html)
Sensible minimum.......
(http://i110.photobucket.com/albums/n95/Dayjo/P1030377_zps2cda77ae.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030377_zps2cda77ae.jpg.html)
Turned right up......
(http://i110.photobucket.com/albums/n95/Dayjo/P1030375_zps1a0fcf01.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030375_zps1a0fcf01.jpg.html)
With those blue tips being blown upward, I think we need some more holes!
Mid setting. It ran the engine perfectly! :ddb: :ddb:
(http://i110.photobucket.com/albums/n95/Dayjo/P1030380_zps41ece1c1.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030380_zps41ece1c1.jpg.html)
A bit of cosmetic work to do on the pot, and drill some more holes..... Job's a good un! :D
David D
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Wow, excellent burner! Nice looking, too. Congratulations! :thumbup: :clap:
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Your cooking with gas now David
Thats a nice blue flame :clap: :clap: :clap: :clap:
Rob
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VT, Rob. Thanks Chaps! :beer:
Drilled a few extra holes.
Some of them, larger diameters. Until testing showed all the little blue flames were where they should be. :thumbup:
So, I reduced the oal height to 1/2", painted and finish assembled......
(http://i110.photobucket.com/albums/n95/Dayjo/P1030392_zps7f7e1d0a.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030392_zps7f7e1d0a.jpg.html)
I'm a bit pleased with my first attempt at making a burner. :)
David D
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Well....... I'm still here! :wave:
Unfortunately, shop time and enthusiasm have been hard to find recently. :(
But, I've sourced a rubber wood base, and gas tank......
(http://i110.photobucket.com/albums/n95/Dayjo/P1030467_zps11858145.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030467_zps11858145.jpg.html)
It runs ok, so far.......
(http://i110.photobucket.com/albums/n95/Dayjo/P1030468_zpsc066984b.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030468_zpsc066984b.jpg.html)
Trying to get me head around plumbing the water tower. It needs up/ down pipes.
I intended to solder direct into the side. But, don't like that idea, now........
(http://i110.photobucket.com/albums/n95/Dayjo/P1030481_zpsb046d6fc.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030481_zpsb046d6fc.jpg.html)
Cos it needs to unplug from the engine stubs......
(http://i110.photobucket.com/albums/n95/Dayjo/P1030482_zpscbbd041c.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030482_zpscbbd041c.jpg.html)
Thought, mebbe I could solder in, boiler type bushings.
Then plumb lower pipe through a 90* elbow, and upper, bend to horizontal.......
(http://i110.photobucket.com/albums/n95/Dayjo/P1030486_zps128c1007.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030486_zps128c1007.jpg.html)
Anyone else got a better idea? :scratch:
Are there any better looking, 8mm dia fixings, than these?
(http://i110.photobucket.com/albums/n95/Dayjo/P1030483_zps9a8aa45e.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030483_zps9a8aa45e.jpg.html)
It's nice to be back! :thumbup:
David D
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Entertaining Grandad's little sweetheart, took up a lot of time today.
She loves to potter in the workshop. But, doesn't like the noise of the machines, as yet!
Managed to get the bushes soldered in. Then spent ages tweaking/ adjusting the pipes to fit, "just so"......
(http://i110.photobucket.com/albums/n95/Dayjo/P1030494_zpsfb8807a5.jpg) (http://s110.photobucket.com/user/Dayjo/media/P1030494_zpsfb8807a5.jpg.html)
I was going to fix the copper pipework in place with sleevelock.
But, I reckon blue Hylomar will do the job, allowing a little flexibility, and easy adjustment, if necessary.
David D
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David
Did you by chance make up some drawings of that engine and pump? I would like to make a larger version of it. I'll look for them from other sources but if you have it would be nice.
Another fine job, Ally
Nelson Collar
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Nelson.
No drawings, at all..... Though I'm sure they will be available from Poly.
I just followed what came out of me head........ :scratch:
David D
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Assembly time!
I'm not sure how hot the burner body will get, under there. Don't want any charred wood!
So, I decided to stand it on 3 wood-screws......
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030496_zps0938aea2.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030496_zps0938aea2.jpg.html)
Gas tank, with it's operating lever........
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030498_zps1248b8cb.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030498_zps1248b8cb.jpg.html)
And the assembly, assembled......
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030499_zps30bf2ca7.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030499_zps30bf2ca7.jpg.html)
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030501_zpsa585a378.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030501_zpsa585a378.jpg.html)
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030500_zps04f1b28b.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030500_zps04f1b28b.jpg.html)
Busy, for the next few days. Video, eventually. :thumbup:
David D
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Looks the business that David :thumbup: :beer:
Looking forward to the video too :)
Ralph.
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Looks stunning David :bow: :bow: :bow: :bow:
I like how its all self contained on one base :smart:
Rob
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It's a beauty, all finished and ready to run. You will be very proud of that one when you demonstrate hot air engine principles to young and old. I'm sure everyone will love it. First rate! :clap: :clap: :clap: :clap:
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Looking great Dave excellent job, :thumbup: :thumbup:
One ?:- what is Mrs Drilling going to use for a bread board now you are using it for the engine base.
:lol: :lol: :lol: :lol:
Stew
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Ralph, Rob, Steve(?). Thank You all! :thumbup:
Stew. Thanks! Re- Mrs. Drillin......... As long as we keep on buying Warburtons sliced, she'll never know! :)
So.........
Yesterday, I fired up, at the start of a full heat test run. Away she went, running nicely, as usual. :thumbup:
Time to fill the cooling system. Using a 5% mix of Shell Supercut-Plus, instead of the previous Bluecol top up mix.......
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030527_zps8e3dd356.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030527_zps8e3dd356.jpg.html)
A couple of minutes later, the well remembered water boiling sounds started. And she stopped. :bugeye:
This proves, once again. Stirling Principle engines will not run on steam! :bang: :bang:
Removing the thumbscrew, and extracting the stainless steel air tube, revealed smears of coolant.
The fluid must be leaking up the outside, and into the power cylinder. :palm:
I machined 3off, 5thou deep recesses, into the tube's o/d. To hold the Hylomar, and seal between air tube and brass tube's bore.
Then I fired up the burner several times, spinning the engine to allow it to breath, and dry out.
Left the system open, and this morning all was well, and dry. :D
Generous application of Hylomar sealed it, as hoped.
Set up, in the kitchen. Not a particularly good idea, so I was informed....... :(
But all went well, during a half hour run.......
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030524_zps93de23b9.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030524_zps93de23b9.jpg.html)
Observations.
The burner system is too on/ off. Also, needs a smaller diameter, more concentrated flame.
Smoke from under the feet, indicated things were getting much too hot. Couldn't touch the underside of the base wood! :bugeye:
The copper chimney got a bit warm, too.......
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030528_zps1eb69d6e.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030528_zps1eb69d6e.jpg.html)
I'm going to try this choke ring, next. Failing that, it's a new rose, with a smaller drilled area.......
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030529_zps5fc66769.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030529_zps5fc66769.jpg.html)
Must look for a No 3 jet......
David D
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David, would it be of help to line the cast base with a thin sheet of insulation on the inside? You might need less heat for the displacer cylinder that way, as well as keeping the base legs cooler. The stack could also be insulated on the inside to keep it cooler. Not sure what to use in place of a sheet of asbestos paper these days, but there might be something healthier out there.
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VT.
Thanks for the insulation thoughts. :thumbup:
I'll see if I can first, reduce the burner's power somewhat. :scratch:
Had another test run today. Just over 1/2 hour.
The burner is better, with the choke ring. But, there's still a lot of heat, where it's not wanted. Some lovely colours on the copper chimney!
Have started to make another rose. Probably, with 1.5mm holes, over a 3/4" diameter area.
Also, ordered a couple of No 3 jets. (One for the Huxtable).......
David D
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Here's a little conundrum.......
The new crankshaft bearings I'd made had too much clearance, on the 6mm silver steel shaft. :(
So, I bought some 10mm o/d needle roller bearings. Mounted the pedestal on a mandrel, and recessed each end of the casting bore, to suit.
The needle rollers had a bigger wobbability factor than my original bushes!! :bugeye: :bang: :bang:
Can't work that out. Am I missing something? :scratch:
Managed to locate four ball races. 6 x 10 x 3mm.
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030578_zpsbcf62336.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030578_zpsbcf62336.jpg.html)
And these fitted perfectly, in pairs, at either end of the pedestal........
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030579_zpsbfcdd84d.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030579_zpsbfcdd84d.jpg.html)
Job's a good un. But, I still can't work out why the rollers seem to be oversize, on the 6mm shaft....... :scratch:
David D
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Are they quarter inch?
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Dave
Some needle rollers need to have a specified interference fit to make 'em the right size.
As do IIRC Glacier bushes.
Also, but I'm not sure about this, some ball-races have polished rings on them. I think this is a similar thing.
ie. Interference fit outer, push fit inner etc. etc. etc.
Dave BC
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As Dave BC says the needle roller bearing need to be pressed in to a a sized hole and must run on a hardened shaft
as to the hole size you need the manufactures spec sheet as to the correct hole size for the outer they are designed to shrink down to the correct size.
as a side note my dad was a foreman fitter at Stanton central workshops they had made a large ball race made by SKF it was about 36 inch bore , when it arrived a. the bore was to small and b. you could move the inner race inside the outer axially by about 1/8 inch.
So on the blower get the rep down here fast this is a load of junk ect. So the rep arrives no the race it to specs , he then had them make up some go logo test bars to his figures , ok get them over the gas heaters until the gauges fitted the bore , pick them up with the crane the slid on the shaft like a well oiled jack boot , when cooled down there was no play and every one was happy and then retired to the Severn Oaks
That was the old works pub as the furnace side workers as part of their wages had 8 pint of beer per shift supplied :D
Stuart
Good work with the engine
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VT.
Nomate....... Not that big. Seems around 5 thou clearance.
Dave, Stuart.
Thanks for that. Not the sort of thing I get up to these days. Or, even previously! :scratch:
Popped the packet of 5, into a tub marked BEARINGS. Along with the previous freebies, from yourself, and Deco. :thumbup:
David D
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I said it was too getting hot, under her skirt. Didn't I? :bugeye:
Even with the choke ring, the present burner is too enthusiastic....... :palm:
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030541_zps26f8c412.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030541_zps26f8c412.jpg.html)
Some mica insulation, under the feet........
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030542_zps982a7229.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030542_zps982a7229.jpg.html)
Fitted a No3 jet, and made a smaller rose.......
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030535_zps7c0afbd6.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030535_zps7c0afbd6.jpg.html)
Good. But still too much........
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030548_zps84605c2c.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030548_zps84605c2c.jpg.html)
So, I reduced the burner area even more........
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030586_zpse3558b46.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030586_zpse3558b46.jpg.html)
And, I reckon it could still work well, even smaller........
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030588_zps6050e1ae.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030588_zps6050e1ae.jpg.html)
Start up from cold, is now "instant". 10secs is all she needs to begin to run.
Here's a little vid, during a 1hr test run. Mounted on a plastic turntable. Should give a smile.......
That was when I realised the flywheel balance weight was out of sync. After fitting the new bearings! :Doh:
Just got to find why she clonks, when hot. But not when cold........
David D
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David, displacer grows when hot, contacts end?
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David, displacer grows when hot, contacts end?
It has to be something similar....... :scratch:
Though it seems to be in sync with the power piston. At tdc. During the changeover between suck/ blow.
The Huxtable engine does the same thing. But, not as noticeable.
Strange things, hot air engines. Love 'em! :thumbup:
David D
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David Is the bore bell shaped? Can't remember if you did (or needed) a re-bore and oversize piston in the re-build....
I can imagine clack at TDC happening on a hot air power piston if the piston crown wasn't parallel with the wrist pin, or if the piston skirt wasn't long enough compared with the distance from wrist pin to crown -- assuming a little play in the bore at TDC.
As a guess, piston would tend to ride slightly skewed, and change the skew angle when the pressure changes sign. Clack would happen then.
Loose wrist pin would also do it .... though at both ends of the stroke
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As an addendum to the burner development.......
Gas power is usually used, to get as much heat as possible, under a boiler.
The problem is. I need a gentle, controllable, flame.
It finally dawned on me, what's needed, is lower gas velocity. Provided by larger holes!
As an experiment, I removed the rose insert. But it then insisted on burning, down inside the body.
Made a rose, with 3.5mm holes. (And 2mm central hole, which was already in the piece of bar).
The old, and new roses.......
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030861_zps3e031a1e.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030861_zps3e031a1e.jpg.html)
No. 3 jet, giving a full flame. Which doesn't blow itself out when full on.......
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030863_zps2bd31fac.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030863_zps2bd31fac.jpg.html)
But will turn down, sufficient for the engine to stop, with the burner still lit.......
(http://i110.photobucket.com/albums/n95/Dayjo/Return%20Album/P1030868_zpsec21d470.jpg) (http://s110.photobucket.com/user/Dayjo/media/Return%20Album/P1030868_zpsec21d470.jpg.html)
Heading the right way, now. I think!
David D
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Getting there David, Lovely engine!
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Getting there David, Lovely engine!
Hi Ross.
Thanks Mate! :thumbup:
David D
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That looks really good, David! :thumbup: :clap: