Model Engine Maker

Engines => Restoration of Model Engines => Topic started by: simplyloco on December 21, 2018, 11:37:15 PM

Title: Restoring a Stuart Turner No. 9 Mill Engine
Post by: simplyloco on December 21, 2018, 11:37:15 PM
I've been away for a while, finishing my Britannia locomotive, but I was given an ancient Stuart Turner No.9 engine today, and I'm quite excited about restoring it! I'll do this in parallel with the build of a 4" Scotch boiler to power it, and perhaps also power the Beam Engine I built last year. I'm back on this site because the MECH site where the Brit resides is all about trains: I'm a model engineer, not a Station Master...
Here's how it looks, all seized up. Close examination showed it to be probably an 'Apprentice Piece', worked on by a few oiks - like me at that age!
Like a Curate's Egg, parts of it are excellent: the cylinder bore is a delight - other parts though, leave a lot to be desired! The crankshaft is bent, and the main bearings have never been line reamed so it is as tight as a drum. I've reamed the bearings, but a new crank is required.

(https://farm5.staticflickr.com/4862/31470845117_f6997d94d1_k.jpg) (https://flic.kr/p/PWYiPT)WP_20181221_20_05_28_Pro (https://flic.kr/p/PWYiPT) by inkaboat (https://www.flickr.com/photos/28837250@N07/), on Flickr

Watch this space. I want to bring it up to the standard in this video:
CbEe6iOSxnYBTW here's the Brit needing just a few touches to finish it, but I've just been distracted by this engine!
John

(https://farm2.staticflickr.com/1931/31323273887_7ef653f827_k.jpg) (https://flic.kr/p/PHVY3k)WP_20181210_17_21_20_Pro (https://flic.kr/p/PHVY3k) by inkaboat (https://www.flickr.com/photos/28837250@N07/), on Flickr


Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: crueby on December 22, 2018, 12:53:46 AM
Going to be a very nice Stuart engine, already is a beautiful loco!
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: steamer on December 22, 2018, 02:35:48 AM
Always loved the 9....I'll be watching along!

Don't be afraid to show some of that locomotive either!......Nice!

Dave
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: 10KPete on December 22, 2018, 04:03:16 AM
That has a pretty good knock in it! Persevere!

Peter
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: Kim on December 22, 2018, 07:20:39 AM
Wow! Love your Britannia! As others have said, please feel free to post some pics of your locomotive.  You've done a nice job on it!

I'll be watching your Stewart restoration too.

Kim
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: Ian S C on December 22, 2018, 11:28:47 AM
Rebuilt one two or three years ago, I think the one I did started off worse than yours, but it came up good. Then the owner took the engine to a steam  weekend show, and it got nicked, which caused us to be a bit miffed.
Ian S C
         
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: ChuckKey on December 22, 2018, 06:09:43 PM
Not only does the example in the video knock, the crankshaft wobbles too.
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: simplyloco on December 22, 2018, 06:20:17 PM
Onwards and Upwards!

I'll be fixing basics first, and making it look pretty later.
The first fault to address was the crankshaft. When the crank was turned, the small end of the connecting rod flailed about like  a Cheerleader's bits pompoms! There had been a pressing error therefore the crank pin was not perpendicular to the webs: one of the bores was 0.004" out of position. The absence of side thrust washers didn't help the situation either!
Today's job was a new crankshaft and thrust washers.

Machining the ends of the webs, utilising a simple stop on the vice jaws.
(https://farm8.staticflickr.com/7901/45698152094_6b9f1fdc06_k.jpg) (https://flic.kr/p/2cCbYw3)WP_20181222_12_02_13_Pro (https://flic.kr/p/2cCbYw3) by inkaboat (https://www.flickr.com/photos/28837250@N07/), on Flickr

Drilling and reaming the two 3/8" holes. There's a balancing piece on the end of the jaws, and I'm using slip gauges on the bed stop to achieve the 0.75" pitch. I can usually repeat holes to 0.0004" or less using this method.
(https://farm8.staticflickr.com/7838/45698151814_43875515ef_k.jpg) (https://flic.kr/p/2cCbYrd)WP_20181222_12_35_15_Pro (https://flic.kr/p/2cCbYrd) by inkaboat (https://www.flickr.com/photos/28837250@N07/), on Flickr

My new Eassom DRO is one thou out when compared to the slip gauge positioning... :headscratch:
(https://farm5.staticflickr.com/4898/45698151394_89e3441f47_k.jpg) (https://flic.kr/p/2cCbYiY)WP_20181222_12_35_28_Pro (https://flic.kr/p/2cCbYiY) by inkaboat (https://www.flickr.com/photos/28837250@N07/), on Flickr

Making them look pretty!
(https://farm8.staticflickr.com/7880/45698151064_81535952c6_k.jpg) (https://flic.kr/p/2cCbYdh)WP_20181222_14_29_30_Pro (https://flic.kr/p/2cCbYdh) by inkaboat (https://www.flickr.com/photos/28837250@N07/), on Flickr

Certainly much prettier than the originals!
(https://farm5.staticflickr.com/4871/45698150664_b1f8cc52ae_k.jpg) (https://flic.kr/p/2cCbY6o)WP_20181222_15_36_46_Pro (https://flic.kr/p/2cCbY6o) by inkaboat (https://www.flickr.com/photos/28837250@N07/), on Flickr

Slip gauges for the gap, and a straight through crank which will be sawn off inside the webs. It's the only way... :LittleAngel:
(https://farm8.staticflickr.com/7843/45698150354_60bcd1f5c3_k.jpg) (https://flic.kr/p/2cCbY13)WP_20181222_16_07_12_Pro (https://flic.kr/p/2cCbY13) by inkaboat (https://www.flickr.com/photos/28837250@N07/), on Flickr

Crankshaft with new thrust washers. No more flailing about and it turns sweet as a nut!
(https://farm8.staticflickr.com/7871/45698149994_aa878980f6_k.jpg) (https://flic.kr/p/2cCbXTQ)WP_20181222_16_59_20_Pro (https://flic.kr/p/2cCbXTQ) by inkaboat (https://www.flickr.com/photos/28837250@N07/), on Flickr

Slide valve is stiff, so that is the next job.
Merry Christmas everyone.
John
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: Gas_mantle on December 22, 2018, 06:56:06 PM
Looking good John, it's amazing how a bit of simple machining can improve the look significantly.

I wondered if maybe the engine had been built by 2 separate people?  From what I can see the cylinder end of the engine looks to be of a better standard than the crankshaft end. The cylinder covers have more studs than the plan calls for so it kinda makes me think the builder wanted to make a good job of it and create an authentic look. I could wrong but the amateurish crank webs and oil cups etc give me the impression they were built by someone less experienced.
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: simplyloco on December 22, 2018, 07:02:33 PM
It's definitely an 'Apprentice Piece', judging from the varying build standard! The cylinder is a delight, the rest is gruesome...
John
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: simplyloco on December 23, 2018, 06:27:49 PM
Well, it leaks like a sieve - it's held together with CSK 5BA screws as I have to get some decent studding-  and the flywheel wobbles, but it works and it doesn't knock! Just click on the pic to get you into flickr, and watch 33 seconds of satisfying model engineering! Please forgive my shaky handwriting and the noisy compressor.
I now have to make it look pretty...
John

(https://farm8.staticflickr.com/7826/31495504687_b84aa5ccd8_b.jpg) (https://flic.kr/p/PZ9GfT)WP_20181223_18_06_15_Pro (https://flic.kr/p/PZ9GfT) by inkaboat (https://www.flickr.com/photos/28837250@N07/), on Flickr
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: crueby on December 23, 2018, 07:33:27 PM
Very nice! The new parts did the trick.    :ThumbsUp:
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: simplyloco on December 26, 2018, 06:55:50 PM
Amazing what a bit of emery cloth and oil can do to a very old and scabby cast iron flywheel!
The Gin helps the concentration as it took about an hour...
John
(https://farm8.staticflickr.com/7856/46475501641_e4ca0e2793_k.jpg) (https://flic.kr/p/2dNT6sr)DSC00657 (https://flic.kr/p/2dNT6sr) by inkaboat (https://www.flickr.com/photos/28837250@N07/), on Flickr
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: Jo on December 26, 2018, 07:32:21 PM
 :thinking: It didn't need much gin to get that finish John. Or was that just enticement to encourage you to get it done  ;)

Jo
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: Gas_mantle on December 26, 2018, 07:43:09 PM
If you drink enough gin the wheel will look fine without polishing - infact both of them will  ;)
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: simplyloco on December 26, 2018, 09:22:38 PM
:thinking: It didn't need much gin to get that finish John. Or was that just enticement to encourage you to get it done  ;)

Jo
Quite right: I was,looking forward to my reward!
John
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: kvom on December 27, 2018, 12:34:58 PM
A friend of mine is just starting a build of a #9.  He doesn't post online but perhaps I'll get pics one of these days.
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: simplyloco on December 27, 2018, 07:26:49 PM
Realigning the Bearings

Now I've got it running I started taking it apart for closer examination and subsequent painting. Gawd, it's a mess...
The lower halves of the crank bearings were not the same thickness, and were sitting 15 thou and 40 thou respectively proud of the chairs, which were not the same depth, so tightening up the top halves on the studs turned them into quite effective G clamps! In addition, the running base for the crosshead was like a ploughed field, so that had to be sorted out. I'm going to make a new crosshead from bronze, so I can compensate for the 15 thou drop in height.
All good fun!

Clocking up on the EMCO
(https://farm8.staticflickr.com/7844/46438376172_112e120eec_k.jpg) (https://flic.kr/p/2dKAPm9)WP_20181227_16_27_04_Pro (https://flic.kr/p/2dKAPm9) by inkaboat (https://www.flickr.com/photos/28837250@N07/), on Flickr

The chairs are now the same depth and perpendicular. The bearings are about two thou proud which is probably about right.
(https://farm5.staticflickr.com/4814/45576707445_8778edf32f_k.jpg) (https://flic.kr/p/2crsxfM)WP_20181227_17_24_37_Pro (https://flic.kr/p/2crsxfM) by inkaboat (https://www.flickr.com/photos/28837250@N07/), on Flickr

A nice flat base for the cross head.
(https://farm8.staticflickr.com/7855/31549981117_10ea9947bd_k.jpg) (https://flic.kr/p/Q4XUcF)WP_20181227_18_14_49_Pro (https://flic.kr/p/Q4XUcF) by inkaboat (https://www.flickr.com/photos/28837250@N07/), on Flickr


Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: ettingtonliam on December 28, 2018, 07:10:42 PM
Originally the No.9 had a forged crankshaft, (or maybe a steel casting) at least mine did in 1965. Yours seems to be missing the valve rod support casting, though the bedplate has been drilled for it. Its a slightly different casting if you want to fit the governor (Oh, please do, it looks so much better)
Mine was built without the benefit of a milling machine, so the bearing housings were filed out, and the lower bearings filed to fit. Closely supervised by my teacher I may say, so they were a pretty close fit in the end.
The inlet ports were cast in, but the exhaust port wasn't, so I had to chop it out with a weeny cold chisel---.
It did run in the end though.

Are you sure that 4" dia boiler is going to be big enough to run an engine with a 1 1/2" x 1 1/2" cylinder?
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: Gas_mantle on December 28, 2018, 07:21:46 PM
Are you sure that 4" dia boiler is going to be big enough to run an engine with a 1 1/2" x 1 1/2" cylinder?

My 3" boiler runs an engine I build using a no9 cylinder, it won't run at high speed for long but at a modest speed it will run all day for demo purposes.

cFsKG-3geHE
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: simplyloco on December 28, 2018, 07:41:19 PM
Are you sure that 4" dia boiler is going to be big enough to run an engine with a 1 1/2" x 1 1/2" cylinder?

My 3" boiler runs an engine I build using a no9 cylinder, it won't run at high speed for long but at a modest speed it will run all day for demo purposes.



Excellent! By a happy coincidence, I'm building a 4" Scotch boiler strictly to the KN Harris design  to demo the little Sirius that I will be making soon. I've not made any connection to it on this thread as this No.9 is a pleasant interlude while I wait for the Sirius crankcase to arrive, so the question was quite unnecessary.
John
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: Gas_mantle on December 28, 2018, 07:56:00 PM

Excellent! By a happy coincidence, I'm building a 4" Scotch boiler strictly to the KN Harris design  to demo the little Sirius that I will be making soon.

John, are you intending to show your boiler build here?  I'd be interested to see how it develops  :)
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: simplyloco on December 28, 2018, 08:19:13 PM

John, are you intending to show your boiler build here?  I'd be interested to see how it develops  :)

Probably, as the people on the MECH site aren't that interested in things that don't move under their own power... :ShakeHead:
I could combine it with the Sirius build.
John
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: Gas_mantle on December 28, 2018, 09:05:34 PM
That would be great thanks  :)
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: ettingtonliam on December 28, 2018, 09:19:12 PM
Are you sure that 4" dia boiler is going to be big enough to run an engine with a 1 1/2" x 1 1/2" cylinder?

My 3" boiler runs an engine I build using a no9 cylinder, it won't run at high speed for long but at a modest speed it will run all day for demo purposes.



Excellent! By a happy coincidence, I'm building a 4" Scotch boiler strictly to the KN Harris design  to demo the little Sirius that I will be making soon. I've not made any connection to it on this thread as this No.9 is a pleasant interlude while I wait for the Sirius crankcase to arrive, so the question was quite unnecessary.
John

So sorry you find my question to be quite unnecessary. You did comment in your first post that the Scotch boiler would power the No.9. Stuart's catalogue for 1974 suggests their Babcock No. 504 boiler with a drum 3 1/2" dia x 10 long will steam the No. 9 just for demonstration purposes, and I think the Babcock is somewhat bigger than the Scotch boiler.
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: oehrick on January 24, 2019, 05:55:12 PM
Compare the heating surfaces, the Stuart 'Babcock' is a pot boiler with a very few watertubes, the Scotch is an internal furnace multiple firetube boiler, no comparison IMO and working hard the #9 has a healthy appetite
Title: Re: Restoring a Stuart Turner No. 9 Mill Engine
Post by: simplyloco on March 26, 2019, 06:43:41 PM
All the way from China for 40 quid, delivered! Lovely bit of kit, and the valve starts to operate at about 600 rpm. I don't know if it will stay where it is  now, there's a problem with the steam delivery!
BTW, a machined governor castings set from Stuart Turner costs 317.88 and it still has to be assembled... :Mad:

(https://farm8.staticflickr.com/7898/47473489851_0727da77cd_k.jpg) (https://flic.kr/p/2fk53zH)20190326_181518 (https://flic.kr/p/2fk53zH) by inkaboat (https://www.flickr.com/photos/28837250@N07/), on Flickr