Author Topic: 'WIDE A WAKE' a steam launch tale  (Read 233878 times)

Offline K.B.C

  • Full Member
  • ****
  • Posts: 166
Re: 'WIDE A WAKE' a steam launch tale
« Reply #600 on: May 27, 2016, 12:03:48 AM »
Dave ,
Don't think that I was explicit enough in my question, I didn't mean the model I just wondered if you had a connection to the 12"-to 1ft vessal and your post has answered that.

Many thanks
George.
Your never too old to learn.

Offline crueby

  • Full Member
  • *****
  • Posts: 18559
  • Rochester NY
Re: 'WIDE A WAKE' a steam launch tale
« Reply #601 on: May 27, 2016, 01:21:51 AM »
Speaking of the Sabino, if you go to the seaports site you can follow the rebuild they are doing. Only big issue is money for the boiler, they may not have it running for a while waiting for more money. Anyone want to make a really BIG model boiler?!

http://www.mysticseaport.org/shipyard/

Sorry for the side trip, back to your wonderful model!!

Offline Ramon Wilson

  • Full Member
  • ****
  • Posts: 1942
  • Suffolk in the UK
Re: 'WIDE A WAKE' a steam launch tale
« Reply #602 on: July 05, 2016, 11:11:43 PM »
Hi Guys, apologies for the delay but it's been a nice break  :)

Well, the 'plastic distraction' has reached it's conclusion for the time being so now it's time to get back on this and see it through.

The boat was brought back into the workshop today and time spent assessing what needs to be done. First off is to make a regulator for the engine and get it coupled up to the boiler then make the pumps. Pretty basic stuff so I won't post anything in detail on that progress just the odd update on progress.

Bearing in mind those previous requests however the first thing I did do was to have another go at a short video - short indeed but enough to give you an idea of how it runs. You can hear the knocking quite clearly - I can't quite trace it specifically but I'm sure it must be those bearings. The air pressure was set to 20 psi so it should have more than enough power at 60 psi of steam.
[youtube1]https://youtu.be/eZK4BVlt5II[/youtube1]

That's it then - it's back on the bench, work is underway  :)

Regards - Ramon
"I ain't here for the long time but I am here for a good time"
(a very apt phrase - thanks to a well meaning MEM friend)

Offline Don1966

  • Full Member
  • *****
  • Posts: 6817
  • Columbia, MS
Re: 'WIDE A WAKE' a steam launch tale
« Reply #603 on: July 06, 2016, 01:29:12 AM »
That's just awesome Ramon and a beautiful job. After watching the video and listening to the knock, it sounds like the back connecting rod is hitting the side of the frame facing the camera. At least that's my observation.

Don

Offline derekwarner

  • Full Member
  • ****
  • Posts: 833
  • Wollongong ...... Australia
Re: 'WIDE A WAKE' a steam launch tale
« Reply #604 on: July 06, 2016, 03:20:50 AM »
Amazingly smooth Ramon.........at about 60 RPM [@ 1:26 minutes] by my counting via the grub screw in the flywheel ....

My level of expertise dictates I should not offer a thought on the knock  :headscratch: ...however that does appear to be a cheapskate air metering device  :ShakeHead: in the video [Starrett tool makers clamp squashing the tube?]

We do look forward to the engine installation in the hull.....

Derek  :cheers:
« Last Edit: July 06, 2016, 08:23:39 AM by derekwarner_decoy »
Derek L Warner - Honorary Secretary [Retired]
Illawarra Live Steamers Co-op - Australia
www.ils.org.au

Offline Jasonb

  • Full Member
  • *****
  • Posts: 9467
  • Surrey, UK
Re: 'WIDE A WAKE' a steam launch tale
« Reply #605 on: July 06, 2016, 07:49:30 AM »
Running nicely Ramon, look forward to seeing this one progress towards launch date.

Could it be a piston getting a bit too close to a cylinder cover?

Offline Ramon Wilson

  • Full Member
  • ****
  • Posts: 1942
  • Suffolk in the UK
Re: 'WIDE A WAKE' a steam launch tale
« Reply #606 on: July 06, 2016, 11:38:25 AM »
Hi guys - thanks for looking in  :)

Tsk Tsk Derek - cheapskate indeed  :o I'll have you know that is a carefully designed rotary operated, pincer movement, infinitely variable, silicone based pressure control device of the finest calibre - just awkward to connect a servo too. BTW That grub screw hole is from it's previous life - it's due for filling in and re-surfacing

Don,  if there is one area were I thought it was coming from it is as you suggest but though the clearance is minimal I have checked it whilst running with cigarette paper and I am absolutely satisfied it's not there. Same with your suggestion Jason - the crankshaft turns by hand through 360 without a hint of a tight spot and I did allow a mm of clearance at both ends.

Thanks for your thoughts though - much appreciated  :ThumbsUp:

Been making the engine regulator parts this morning  :)

Regards - Ramon
"I ain't here for the long time but I am here for a good time"
(a very apt phrase - thanks to a well meaning MEM friend)

Offline derekwarner

  • Full Member
  • ****
  • Posts: 833
  • Wollongong ...... Australia
Re: 'WIDE A WAKE' a steam launch tale
« Reply #607 on: July 06, 2016, 12:33:34 PM »
Ramon...

Whilst I am often questioned for suggesting the use of technically inexpensive electronic equipment associated with our model steam projects, you could always revert to an also inexpensive version of a sonoscope...being a 6" screwdriver plugged against the middle outer lobe of your earhole :shrug:....and the other end carefully positioned on varying surfaces of the components of the engine and listening for the.....  :Director: source of the sound......the lower the rotational speed, the greater the perception and understanding will be

I would be surprised if you could not identify the source of the sound by such a simple but  :happyreader: well proven method

Derek

« Last Edit: July 06, 2016, 12:38:02 PM by derekwarner_decoy »
Derek L Warner - Honorary Secretary [Retired]
Illawarra Live Steamers Co-op - Australia
www.ils.org.au

Offline Ramon Wilson

  • Full Member
  • ****
  • Posts: 1942
  • Suffolk in the UK
Re: 'WIDE A WAKE' a steam launch tale
« Reply #608 on: July 06, 2016, 01:15:24 PM »
Ah Derek, I do indeed have a drawer full of such technical 'stethoscopes' but not one of them can detect the location of this irritating knock - Straight end, Phillips, even Ball Nose but not so much as an indication :-\ - yep - tried that but no result  ::)

Believe me I have gone through everything short of isolating each cylinder from the other. I'm convinced it's the big end bearings but can't be 100% certain. Plan is to make new ones anyway then I will try one cylinder at a time. As you can see it runs very slowly - it has not a hint of a tight spot nor a wring so at this stage it is a tad perplexing.

As always thanks for your input :ThumbsUp:

Regards - Ramon
"I ain't here for the long time but I am here for a good time"
(a very apt phrase - thanks to a well meaning MEM friend)

Offline crueby

  • Full Member
  • *****
  • Posts: 18559
  • Rochester NY
Re: 'WIDE A WAKE' a steam launch tale
« Reply #609 on: July 06, 2016, 02:04:57 PM »
If its the big end bearings, seems like you would feel the movement if you grab the conrod and pull up and down.
Any chance it is the small end cross pin?

Offline K.B.C

  • Full Member
  • ****
  • Posts: 166
Re: 'WIDE A WAKE' a steam launch tale
« Reply #610 on: July 06, 2016, 04:30:21 PM »
Ah Derek, I do indeed have a drawer full of such technical 'stethoscopes' but not one of them can detect the location of this irritating knock - Straight end, Phillips, even Ball Nose but not so much as an indication :-\ - yep - tried that but no result  ::)

Believe me I have gone through everything short of isolating each cylinder from the other. I'm convinced it's the big end bearings but can't be 100% certain. Plan is to make new ones anyway then I will try one cylinder at a time. As you can see it runs very slowly - it has not a hint of a tight spot nor a wring so at this stage it is a tad perplexing.

As always thanks for your input :ThumbsUp:

Regards - Ramon

Ah Derek, I do indeed have a drawer full of such technical 'stethoscopes' but not one of them can detect the location of this irritating knock - Straight end, Phillips, even Ball Nose but not so much as an indication :-\ - yep - tried that but no result  ::)

Believe me I have gone through everything short of isolating each cylinder from the other. I'm convinced it's the big end bearings but can't be 100% certain. Plan is to make new ones anyway then I will try one cylinder at a time. As you can see it runs very slowly - it has not a hint of a tight spot nor a wring so at this stage it is a tad perplexing.

As always thanks for your input :ThumbsUp:

Regards - Ramon

Ramon,
There is nothing more irirtating than a knock that you can't decipher where it's coming from, over the years I"ve been there and know how hard it is to find the knock.

In my fault finding experience I have to agree with Don and Jason but you have checked out Dons input although could it be that when running the Fag paper clearance , abouy .002" may not be enough as the centrifugal force of the big ends and suspected worn bearings could cause the knock, although there would be a scuff mark if it was hitting there.
Another scource of knocking is the central bearing, if it wasn't properly fitted and the bottom half loose it could be the scource, on Stuarts drawing it calls for a 3/32" pin to hold the bottom half, on all of the Stuart builds that I have done I fit a 6 ba grub screw coming up from the underside ( pic included ) to hold the 2-halves together, the pic is of a Stuart Score that I am working on at present.

I see that you have checked Jason's suggestion but a few years ago a friend 's D10 started an infernal knocking and eventually stopped running, on examination it was found that the piston had unscrewed and was hitting to underside of the top cover, worth a check !!!!
Since then I always drill 2- holes in the piston which allows the use of an adjusting tool to take the piston s out without a complete dismantle.

Even if the bearings were worn I don't think that the knock would be there at such low revs that your engine acheives.

Knowing your workmanship if you had made the bearings the knock wouldn't be there, don't be dishartened and leave the knock there, you will eventualy find it.

Super job of the engine and just shows that you don't need fancy gear to control the air/steam, even a clothes peg would sufice.

George.
« Last Edit: July 06, 2016, 09:15:09 PM by K.B.C »
Your never too old to learn.

Offline Admiral_dk

  • Full Member
  • *****
  • Posts: 3752
  • Søften - Denmark
Re: 'WIDE A WAKE' a steam launch tale
« Reply #611 on: July 06, 2016, 09:42:33 PM »
It sounds and looks as if the crank is always in the same position when it knocks - if you can figure exactly where, that might point you to the culprit (or the few possible at that point).

Good luck hunting it down.

Per

Offline Ramon Wilson

  • Full Member
  • ****
  • Posts: 1942
  • Suffolk in the UK
Re: 'WIDE A WAKE' a steam launch tale
« Reply #612 on: July 06, 2016, 10:14:04 PM »
Hello George and Chris - good to hear from you and thanks for your input :)

The cross head pin is new, heat treated and fitted to a new crosshead with new top half con-rods so I'm pretty confident there's no slack there to speak of, and yes Chris I have tried what you suggest too  ;). The original big ends used appeared a good fit perpendicular to the crank pin but are able to be rocked from side to side - fore and aft that is. I have a sneaking feeling that this is where the problem lies

It could be the piston moving so I will check that in due course (Pistons have a semi circular slot in them for the same reason as your pin holes George)

On reassembly I checked the crankshaft bearings for any slop and these were very good, however I'm pleased you made the comment about that centre bearing as it is something that I had not considered as possibly a cause. When I dis-assembled the engine I found a very thin shim under one side of the centre bearing top flange but this was left out on assembly to see just how tight the shaft would be without it. Much to my surprise with all three bearings bolted down tight the shaft spins freely between fingers without slop or any tight spots. The lower part of the centre bearing sits over a screw in peg which prevents rotary movement but there's no immediate way to tell if it is loose ie not actually in contact with the shaft - I'll now check this out too.

At this point in time it is not causing a problem but more an annoying characteristic and only then mainly because of not being able to find the source. I remember when the Waller first ran there was a similar knock which took some time to source - ears and screwdrivers certainly came into play then Derek  ;) - but in the end I noticed the shaft had a very slight sideways oscillation in it's bearings - the heights of the two bearing blocks were slightly out and a 2 thou shim cured not only the oscillation but the knock too.

We'll find it - you betcha!

Regards - Ramon

PS Per - your post has just come up as I previewed this. Thanks for your input too - I find something like this an enjoyable challenge even if mildly perplexing - if I do find and cure it then I shall be well pleased  :)


"I ain't here for the long time but I am here for a good time"
(a very apt phrase - thanks to a well meaning MEM friend)

Offline derekwarner

  • Full Member
  • ****
  • Posts: 833
  • Wollongong ...... Australia
Re: 'WIDE A WAKE' a steam launch tale
« Reply #613 on: July 06, 2016, 11:35:27 PM »
Ramon......just a few questions..& thoughts

1. is that JS Bach  :bandrock: being played quietly in the back ground during the initial tests?
2. did you close your eyes when using the screwdriver to the earlobe check?
3. can you slow the video speed down and determine the position of knock relative to the flywheel grub screw positioning?
4. the fact that you can turn the engine over without any perceived tight spot would suggest that neither piston is hitting at TDC, further if a piston had any vertical float you would expect the audible knock to occur both at TDC and BDC

Another possibility to pin point the area is to selectively wash & flood all lubricant from one [1] selected joint/journal only......re-flood with a more viscous goop & repeat the tests but only at that nominal 60 RPM speed...if OK, wash and refill with your standard grade bearing oil

From this you have 7 individual external areas to check via the same process

A further consideration could be to mount the engine securely to a robust steel bed, and with a magnetic based long probed dial indicator with hand rotation check for any eccentric indication

If all else fails.... :facepalm:..it would also be interesting to run the engine on a slow but extended steam trial [95 degrees C internals]...[as opposed to lubricated air @ 20 degrees C]


Derek
Derek L Warner - Honorary Secretary [Retired]
Illawarra Live Steamers Co-op - Australia
www.ils.org.au

Offline steamer

  • Global Moderator
  • Full Member
  • *****
  • Posts: 12697
  • Central Massachusetts, USA
Re: 'WIDE A WAKE' a steam launch tale
« Reply #614 on: July 07, 2016, 12:24:11 PM »
Derek's point about flooding with a heavy oil ...one at a time, is a very good one.   

Don't forget to check  the crossheads....always a possibility.

Dave


"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

 

SimplePortal 2.3.5 © 2008-2012, SimplePortal