Rachel – Wall Engine

[klankParticipant @klank]

I have just started making this model from the GLR castings and plans as supplied. plus the series of articles on its construction by Stan Bray in the ME

 

Although in the early stages of the build, there are a couple of points I cannot understand.

 

1. Is there any reason why the main bearings are split in Stan Bray’s text?

 

The plans do not appear to mention this and it would be a lot simpler and easier to machine them from the solid, rather than fabricate them the way Stan has written. (Please note this is not meant as any criticism of Stan’s work.)

 I can understand the need for split bearings in “full size” practice if the crankshaft has to be taken down, but going by the plans for the model – it does not seem necessary.

 

2. The base plates and spacer bars appear to be drilled for a number of ?dowel pins?

 

There is a series of 2mm holes shown passing through the base/spacer bars and into the frame and big end support castings, yet no mention of their function either on the plan or in Stan’s text. Should dowel pins be fitted before drilling for the fixing machine screws?

 

The dimensions between the hole spacings given in the plans for the base/spacer items are also puzzling – is there an error here?

 

I am still something of a beginner in model building terms and would appreciate any help or advice if anyone has built this model.

 

Peter

[klankParticipant @klank]

[JasonBModerator @jasonb]

No real reason that the bearings need to be split but it would allow you to take up any slight wear if the engine is to do a lot of work.

 

You may find this guys Build diary helpful, to get the build click zum baubericht at the bottom of the page, you can also past the url into a translator such as Bablefish and read what he has to say, may explain teh dowel pins and sizes.

 

Jason

[klankParticipant @klank]

Thank you Jason for the most useful reply.

 

As you suggested I have used Babelfish to obtain an (approximate/literal!!) translation to what is a very useful build diary. Some interesting technical German words which appear untranslateable – but it makes sense.

 

My, that guy does some superb work.

 

It would appear that there are dowel pins to be used in the baseplate/spacer bars before drilling through – not mentioned in Stan’s text.

 

Interestingly, his photos show what th small rectangular “cut-out” is for in the base of one of the bars – some sort of hole to fit a pressure gauge, or some such (marked as “5” on the GA drawing) but again not mentioned in Stan’s text.

 

Hole spacings sorted – a few typo’s on the plans is all.

 

You have helped greatly with that link – I shall press on into the unknown with some greater confidence.

 

Thanks again and with best wishes

 

Peter

[WearyParticipant @weary]

Klank/Peter,

 

If you have found some errors or typo’s on the plans can you let GLR know so that the plans can be corrected and updated .  In tihs way future modellers may be saved from having to follow the same path of discovery as you have done.

 

I only mention it because you state that you are a new modeller.  

One of the perennial complaints is incorrect plans – even on plans which are extremely old – each individual modeller discovering the same errors. correcting them for himself, and the publisher carrying on issuing the incorrect plans unaware of the errors.

 

Regards,

 

Phil

[klankParticipant @klank]

Phil – sorry for the long delay in replying to your suggestion.

 

There IS a major error in the plans currently supplied with the kit.

 

Briefly, these plans (GA Drawing – sheet 12) show the centre line of the crankshaft to be above the centre line of the cylinder/valve chest/pump bore etc. and a 1mm “step” to be milled out of half the length of the brass distance pieces.

If this is followed in the build – the engine won’t work due to a misalignment.

 

The general arrangement drawing shown on page 742 of the ME at the start of the series of articles (22.6.2007) actually shows the CORRECT view – i.e. everything “in line” – which is at variance with the second plan of the base frames published on that page – a plan of the base rails/distance pieces – which shows the “step” (not in the GA drawing above it)!!! That re-drawn plan in the magazine is not included in the plans supplied with the kit (very strange).

 

Anyway, I got this confirmed after speaking to Stan Bray – who did the original build for the ME, using the original Otto plans.

 

I spoke with GLR subsequently, and they will be going back to Willi Schneeburger who re-drew the original Otto plans, and will try to get it all sorted.

 

Sorry about the length of this – but if anyone has just started the kit – beware!!

 

Peter

[Ben atkinsonParticipant @benatkinson85809]

The build diary looks really useful. The builder seems to have included the 1mm step?

The drawings I have (from Kennions) seem to show a cylinder bore of 20mm but a piston diameter of 22!

 

[roy entwistleParticipant @royentwistle24699]

Please note the original article is 14 years old

Roy

[Ben atkinsonParticipant @benatkinson85809]

Thanks Roy. I have already milled the step and am now hoping that, if necessary, a compensatory 1mm can be contrived in positioning the piston guide and cylinder.

[JasonBModerator @jasonb]

This is the engine it is said to be based on the 1882 Otto Lilenthal

And the patent

[Ben atkinsonParticipant @benatkinson85809]

<p style=”text-align: right;”>Thank you Jason! That’s very interesting. I was led to try Rachel by the wall engine at Quarry Bank Mills.</p>
To the extent it matters… I have now correctly read the drawings and the cylinder bore is 22mm.🙃

[Michael GilliganParticipant @michaelgilligan61133]

Following-up on Jason’s interesting lead … I dare not pursue this, but others may find it worthwhile: https://www.lilienthal-museum.de/olma/shop1_9.htm

 

MichaelG.

[Ben atkinsonParticipant @benatkinson85809]

Thanks Michael. I might try and get the leaflet.

[Ben atkinsonParticipant @benatkinson85809]

https://www.lilienthal-museum.de/olma/edampf.htm

It looks like the brochure is only available in German.

[Harry WilkesParticipant @harrywilkes58467]

Thanks Michael interesting link

H

[JasonBModerator @jasonb]

The defunked german magazine Das Danpf-modell had a serie son the engine by the kit designer Dietmar Carsten in the late 90s

[Ben atkinson]

On Ben atkinson Said:

https://www.lilienthal-museum.de/olma/edampf.htm

It looks like the brochure is only available in German.

Sorry, Ben … I should have mentioned that

[ didn’t bother because I thought you were happy with doing translation ]

MichaelG.

[Ben atkinsonParticipant @benatkinson85809]

Thanks Michael. I still might pursue it.

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