Home Model Engine Machinist > Building Them > Engines From Castings > Stuart Turner Launch engine con rod.
Reply
 
LinkBack Thread Tools Display Modes
Old 08-24-2012, 09:56 PM   #21
rhitee93
Project of the Month Winner!!!
 
rhitee93's Avatar
 
Join Date: Mar 2012
Location: West Central Indiana, USA
Posts: 572
Liked 69 Times on 57 Posts
Likes Given: 27

Default

Thanks for posting the pics. That is some nice work you have done



__________________

-Brian

rhitee93 is offline  
 
Reply With Quote Quick reply to this message
Old 09-01-2012, 09:16 PM   #22
KBC
Junior Member
 
KBC's Avatar
 
Join Date: Feb 2012
Location: Glasgow
Posts: 56
Liked 31 Times on 21 Posts
Likes Given: 3

Default Wrongly cast ports.

After finishing the cylinder lagging and all the pipe work it was time to time the engine to fire it up on air I discovered that it was impossible to time the engine, so in speaking to a friend who had built a launch engine he suggested that I check the cylinder ports and to my horror they are way out.
Of all the Stuart engines and pumps that I have made, this being the first launch engine, I have always found the castings to be very good and accurate but the casting of the ports on this one is poor.

To over come this I am making plates from 1/16" thk gauge plate with accurate ports and will plant it between the cylinder face and the steam chest with a chemical filler paste to prevent leakage between the inlet and the exhaust.

Here is a pic of the cast ports which now that I have found out that they are wrong look enormous.

Any other suggestions would be appreciated.

George.



Attached Images




__________________
KBC is offline  
larry1 Likes This 
Reply With Quote Quick reply to this message
Old 09-23-2012, 04:44 PM   #23
KBC
Junior Member
 
KBC's Avatar
 
Join Date: Feb 2012
Location: Glasgow
Posts: 56
Liked 31 Times on 21 Posts
Likes Given: 3

Default End of a Launch engine Saga.

Engine now completed with the Gauge plate inserted between the steam chest and the cylinder casting.
The Stevenson gear now worked , although not very well in reverse and on further investigation it was found that one of the casting for the eccentric sheave was incorrectly cast so a new one was made from a piece of cast iron that I had in the scrap box so all is now well and it's a great running engine.
I must say that it's a sorry tale of very poor castings from Stuart and they would have been returned if I had bought them from Stuart but as they were bought on e-bay the mods had to be made, however it was a learning curve and a warning to check everything against the drawing.
This forum has been an inspiration to me as I am not a machinist and the quality of the work on view has been a great help in trying to emulate the workmanship on view.

I now only have to make an engine driven pump to finish the engine off.

George.

Attached Images










__________________
KBC is offline  
3
People Like This 
Reply With Quote Quick reply to this message
Old 09-23-2012, 07:53 PM   #24
vcutajar
 
vcutajar's Avatar
 
Join Date: Nov 2011
Location: Marsacsala, MALTA
Posts: 850
Liked 115 Times on 91 Posts
Likes Given: 41

Default

Well done George.

Vince

__________________
vcutajar is offline  
 
Reply With Quote Quick reply to this message
Old 09-24-2012, 12:13 AM   #25
Hilmar
 
Join Date: Jul 2007
Posts: 232
Liked 11 Times on 11 Posts

Default

Georg,
on the launch engine, I wonder if the castings where original from Stuart Turner.
On the print from Stuart the valve cover shows only four screws for hold down ,also the cover
has no " S "cast into it. On my castings;" I bought from some one on the web not E Bay" they also lousy castings
and the dimensions are odd and the same just as yours and no 'S' also. They look like a copy.
What do You think.
Hilmar

__________________
Hilmar is offline  
 
Reply With Quote Quick reply to this message
Old 09-24-2012, 12:55 PM   #26
rhankey
 
rhankey's Avatar
 
Join Date: Feb 2011
Posts: 167
Liked 27 Times on 21 Posts

Default

Quote:
Originally Posted by Hilmar View Post
Georg,
on the launch engine, I wonder if the castings where original from Stuart Turner.
On the print from Stuart the valve cover shows only four screws for hold down ,also the cover
has no " S "cast into it. On my castings;" I bought from some one on the web not E Bay" they also lousy castings
and the dimensions are odd and the same just as yours and no 'S' also. They look like a copy.
What do You think.
Hilmar
Hilmar, I have a twin compound casting kit that I hope to start in the next few months that was cast around 1960, and it also lacks the ‘S’ in the valve covers. My old drawings show 4-corner bolts as you describe, but no 'S'. I wonder if/when Stuart ever did include the ‘S’ in the launch/compound engines?

George, I certainly can empathise with the challenges you had with building your twin launch. I’m about 75% along with a triple, being built from modern Stuart castings, and I am also dealing with the same very crude, sand encrusted blobs of metal as you had to. The cast iron has numerous cold spots, and the gunmetal is usually undersize in at least one dimension and I have uncovered a number of hidden holes. The cylinder heads which I’m working on currently, are giving me some challenges. With such poor quality castings I wish Stuart didn’t even bother including the valve ports in the castings, as I’m going tohave to spend much more effort trying to salvage their misaligned and sand filled ports rather than simply drilling/milling my own very precise ports.

I am not sure when Stuart started producing much poorer quality castings, but the difference between their current castings and their older castings is night and day. The castings to my old twin compound kit are gorgeous, crisp, smooth, highly detailed and accurate castings, none of which require any clean-up before they are machined. The same is the case with a Stuart/H.A.Taylor Undertype casting kit from around 1970 that I will be starting after the twin launch.

Robin
__________________

Last edited by rhankey; 09-24-2012 at 12:58 PM.
rhankey is offline  
 
Reply With Quote Quick reply to this message
Old 09-24-2012, 04:35 PM   #27
jrogertaylor
 
Join Date: Mar 2012
Posts: 2
Likes Given: 7

Default

I just finished a beam engine from castings I bought from ST about 30 years ago when they were still in England. They were excellent. But they have moved at least twice and been sold since then.

__________________
jrogertaylor is offline  
 
Reply With Quote Quick reply to this message
Old 09-24-2012, 07:13 PM   #28
KBC
Junior Member
 
KBC's Avatar
 
Join Date: Feb 2012
Location: Glasgow
Posts: 56
Liked 31 Times on 21 Posts
Likes Given: 3

Default

Hi Vince,
Thanks for that.

Hilmar,

I think that one of the problems with Stuart is that they don't do their own castings but farm them out and over the years have tried a few foundries, some successful others not and this is why there can be a difference in cast iron quality.
On the Launch engine drawing it shows a 4- bolt fixing on the steam chest cover but on the drawing for machining the Stevenson reverse gear it show an 8- bolt fixing, this is why mine has the 8- bolt fixing.
The figure 'S' on the cover is only on the 10V, 10H, D10 and Score engines, whereas the Launch engine, Compound engine and the Triple Expansion has a plain cover, I think some of the bigger engines may have the 'S' cast in.

Robin,

I have over the years built many D10's, 10V's and steam pumps with no great complaint on the casting quality but this lot are quite frankly a disgrace and one can only hope that the new owners can get their act together and produce some better castings.

As an Ex design draughtsman/ engineer I can also comment on their drawings which are quite pathetic and in particular how you are supposed to machine the double eccentric sheaves for the reverse gear to the drawing beats me and for other machining there is not one Datum line to work from which I must add is common on all of their drawing for other models.
The drawing for the engine without reverse gear is dated 1972 and the one for the reverse gear is dated 1955 and they have the nerve to charge £20 for them.
Like you I wished that they had not cast in the ports which would allow you to mill them out correctly.

All in all it has been a challenge but I was determined not to be beaten and made a few mods along the way, i.e. the bearing blocks, steel con rods and the drag links for the reverse gear, did away with the grooves to hold the eccentric sheaves in place by making then plain with a flanged end and the main thing being the gauge plate with new ports, now just a boiler feed pump, will post some pics when completed.

Thanks to all who helped in my early en devours.
George.

__________________

Last edited by KBC; 09-24-2012 at 07:15 PM.
KBC is offline  
 
Reply With Quote Quick reply to this message
Old 09-25-2012, 12:31 AM   #29
Hilmar
 
Join Date: Jul 2007
Posts: 232
Liked 11 Times on 11 Posts

Default

George,
You said that you made a cover over the valve ports, did you glued it
in or just let it be loose and how thick did you made it?
Hilmar

__________________
Hilmar is offline  
 
Reply With Quote Quick reply to this message
Old 09-25-2012, 03:13 PM   #30
KBC
Junior Member
 
KBC's Avatar
 
Join Date: Feb 2012
Location: Glasgow
Posts: 56
Liked 31 Times on 21 Posts
Likes Given: 3

Default

Quote:
Originally Posted by Hilmar View Post
George,
You said that you made a cover over the valve ports, did you glued it
in or just let it be loose and how thick did you made it?
Hilmar
Hilmar,

I used a piece of gauge plate 1/16" thk but didn't harden it, just polished it with very fine emery paper.
I smeared the back of the plate with Hermetite green gasket sealer, which goes hard when cured, put the plate onto the old face with the out of line ports and bolted it up with the steam chest casting without the cover on and with the point of my scriber cleaned out the excess sealant, repeat to other end and leave for 24 hrs.
When I undid the nuts and removed the steam chest casting the plate was very firmly stuck on, to date there has been no leakage between the steam inlets and the exhaust out let.

The green Hermetite sealant is very high temp, I use it on my Flash Steam engines to great effect, it can be purchased from some Auto shops or Engineering supply companies.

George.
Pic of the sealant.


Attached Images


__________________
KBC is offline  
 
Reply With Quote Quick reply to this message
Reply


Quick Reply
Message:
Options

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Stuart Twin Launch Engine from set of castings shearwater Engines From Castings 10 02-26-2012 10:44 AM
Stuart Twin Launch Patrik A Work In Progress 10 11-26-2011 11:33 PM
Stuart Turner Triple Expansion Engine 80% finished for sale. malcolmt Buy / Sell / Trade / eBay 0 05-18-2011 03:54 PM
A Stuart Turner Triple Expansion Engine Hilmar Engines From Castings 51 10-22-2009 03:58 PM
Stuart Turner S50 and the boys engine compound driver 2 Engines From Castings 2 11-28-2008 09:50 PM




- Top - Member List