Metcalfe & Davies 2A115 Air Compressor WIP

[Plumber]

Hello All,

 

First ever model post after coming out of my 30 year dark period.

Davies & Metcalfe were a major supplier of braking system components to the rail industry in the post steam years of the BR modernisation program, in the sixties they formed a joint venture with the Swiss company Oerlikon to build a new range of air brake components as this technology started to seriously displace the traditional vacuum braking systems used on British rolling stock.

A main stay of this range was the Type 2A115 air compressor modelled here that was/is ubiquitous across the BR fleet of locomotives.

The unit is a three cylinder two stage design (2 LP cylinders, 1 HP) with inter cooling with the prime mover being a four pole DC motor:

 

The compressor is built from Technic engine components - the pistons are fitted with o-rings to the grooves and the cylinders are reamed to smooth the moulding undulations, the fluted bricks on top of the cylinders are glued in place - the non return valves on each stage outlets are provided by an original pneumatics 'distribution block' with the LP inlet controlled by the piston covering a port drilled in the bottom of the cylinder - the cylinder design is inspired by Lego Technic Embodiment's LPEs from Technic engine parts.

I did experiment  with using  a pair of pneumatic system pumps and a cylinder but the assembly was too tall and the obviously substantially less realistic a model.

I'm fairly happy with the final appearance of the model but the size has exceeded the scale  as it has finished about 1:8 - as this model is one of the first parts of a full locomotive 1:8 is somewhat larger than desirable, so its back to the drawing board to try and reduce the model to 1:12

So here is the first stab at the reduced scale - the functional parts are substantially the same but the casing has had to become much more rigid to help offset the lack of crank bearings between cylinders.

Pretty rough looking but snot is difficult when the interior has to be functional too! WIP.  Would love to get the distribution block back inside the cylinder cowling.

Will post a video of it working once the bricks to remove the colour vomit have arrived.

Edited September 3, 2021 by Plumber
images not working

[Maaboo the Witch]

Hi Simon! If you want to embed images directly, publish them on Flickr and copy + paste the URL into your post.

[Plumber]

Hmm - that's irritating the images worked on the practice forum - can this now only be done from Flickr?

I thought it should work from any external host

 

[Andman]

3 minutes ago, Plumber said:

can this now only be done from Flickr?

Bricksafe.com works too.

[Milan]

16 minutes ago, Plumber said:

I thought it should work from any external host

I have just clicked on your first image, when it opened, right clicked on it, copy image link, and pasted that link into your first post, and it shows. Try to edit your post and do it again.

[Plumber]

Thanks for your replies folks but I'm stumped.

Milan If you do as you say then the picture appears in the reply but then is not there on the board.

I've spent a while looking at the FAQ's and pinned topics on the subject - they all seem to show a whole toolbar in the reply box that is not appearing on my screen that includes a button with a tree on it!?!?!

What I do get is a drop down in the bottom right of reply box attachment banner 'Insert other media' which gives option to 'insert image from URL' - opens an input box where I put URL but then the 'Inert button does nothing - dialog just sits there.

Is it because I'm on a Chromebook that I don't see the proper insert tool?

 after moving to PC

Okay so it seems Chromebook is not compatible with inserting deeplinks as pasting the URL on a PC seems to have done the trick!

Does that need rpeorting somewhere?

Edited September 3, 2021 by Plumber
clarity

[Milan]

It seems you have managed to post the pictures. At least I see them.

So, all you need to do is to paste the link which you have taken by right clicking on the image and "copy image link" directly in the reply box.

[Plumber]

Yes agreed!  Thats exactly what I did on both Chromebook and PC - on PC/Firefox it works, on Chromebook/Chrome it doesn't. Wiser minds than mine will have to puzzle that one out

[Hrafn]

None of the images show for me (using Brave on Android).

[Void_S]

Great! With engine cylunders covered with these bricks you may feel even some resistance due to air pressure.