Quarter Scale Merlin V-12

Buchanan · Jan 26, 2017

Sorry Terry.
I did not explain myself properly. What I was trying to say was to make the bolt on block look like a separate part but make it look a little more like a casting itself. I am in complete admiration of your work in every way, what ever you do.
Deryck

mayhugh1 · Jan 26, 2017

This is what I find amazing:
http://buchananclocks.com/astronomical-extraordinaire/

Ghosty · Jan 27, 2017

mayhugh1 said:
This is what I find amazing:
http://buchananclocks.com/astronomical-extraordinaire/

You are not the only one, love those type of clocks, I know I don't have the ability to do that type of work.
Your work on this engine would be pushing me to limits I don't have, Keep up the great work.

Cheers
Andrew

[ame]https://www.youtube.com/watch?v=iYA13MVMgVA[/ame]

Buchanan · Jan 27, 2017

Thank you very much, but not the reply I expected.

Blogwitch · Jan 27, 2017

Deryck,

If you are into full sized aircraft and engines you would find that most ancillary valves that you are looking at are in fact machined from solid bar, very rarely are they cast unless they were just a cross or T joint, which would be fairly simple to hold and machine, and even then, most of those would be manufactured from billet material.

To make a casting for such a small and most probably an "off the shelf " part would just be too expensive to hold and machine.

John

Rustkolector · Jan 27, 2017

Terry,
I can't say it any better than has already been said.....OUTSTANDING WORK.

In the future you can find more color options and much lower prices on Gun Kote direct from kgcoatings.com. I have used it for many years and it adheres to brass and aluminum better than any other finish. Great stuff.
Jeff

Buchanan · Jan 29, 2017

John. If it is true to scale I have absolutely no problem . If not, its Terry's engine and it is beautiful.I do not have an in depth knowledge of aircraft engines but I can understand you. I just assumed that the valve would have been a die casting. Thanks for the adjustment.
Buchanan

mu38&Bg# · Jan 30, 2017

https://www.flickr.com/photos/36102311@N05/3444679767/in/album-72157615730935253/

While the original was a casting, it does not detract from the work being here.

mayhugh1 · Jan 30, 2017

Dieselpilot,
Thanks for the photos. They contained details I hadn't yet come across in my own research -Terry

dischn2 · Feb 1, 2017

Hi Terry,
can I help you with the original drawing of the housing?
You are doing a great job, but this brass part is ugly

.

Dirk

View attachment 607929.zip

Buchanan · Feb 2, 2017

Oh dear, what have I started. Terry, keep it like it is. It's your engine.
Deryck

mayhugh1 · Feb 2, 2017

No problem...
One of my reasons for posting is to gather comments and opinions from others to use or to not use. The post by dischn2 and the 'like' by cheese.cake.701 seemed a bit suspicious, though. I've been afraid to open that zip file.💀

gadabout · Feb 2, 2017

That file is ok, I opened it and its a drawing , very detailed of a relief valve

Mark

dischn2 · Feb 3, 2017

Hi Terry
I am sorry that you misunderstood my posting. I had to zip the tif file because I am not allowed to post tif files and the file size was also restricted.
Actually the drawing shows the original oil relief valve housing for the V-1650-7 Packard Merlin. I thought I could help you with it

Dirk

rdefrei1 · Feb 3, 2017

I did open the file and it's a legit Engineering Drawing.
It's just a compressed file (.zip)

rdefrei1 · Feb 3, 2017

I was able to change the file extension to JPG.

mayhugh1 · Feb 3, 2017

dischn2 said:
Hi Terry
I am sorry that you misunderstood my posting. I had to zip the tif file because I am not allowed to post tif files and the file size was also restricted.
Actually the drawing shows the original oil relief valve housing for the V-1650-7 Packard Merlin. I thought I could help you with it

Dirk

Sorry for my misunderstanding. Thanks for your help. -Terry

mayhugh1 · Feb 7, 2017

The Quarter Scale documentation suggested machining scaled AN816 37 degree flare fittings for connecting the oil lines to the relief valve housing. For the housing's two output lines I machined a pair of single piece flanges that were intended to only look like threaded fittings. I used faux fittings on these two lines because the runs made up from the rigid tubing were just too short and didn't have the flexibility required to undo a threaded connection. One of my goals in plumbing the oil system was to do it in such a way that the individual lines can later be opened up for maintenance (to verify flow, replace gaskets, etc.) without the need for a lot of secondary disassembly.

Three additional oil lines branch off the far end of the low pressure line at the rear of the engine. These lines feed oil to the internals of the wheel case as well as the camshafts and rockers in the engine's top end. Unfortunately, they need to be routed in the busiest section of the engine and right up against the chain cover and starboard-side distributor.

A sketch in the Quarter Scale's documentation recommended anchoring a stack of banjo fittings to the top of the wheel case to create a union for these lines. In my particular case, this would have required some heroic bends in the 3/32" copper tubing used for the lines. Several days were spent trying to come up with something that looked decent but was still accessible. Bare aluminum (tig) welding rod and lots of trial-and-error was used to develop shapes for these three oil lines. Simple grooved mandrels turned from wooden dowels were used to form the bends. Along the way, I machined lots of brass fittings that ended up not being used. One batch of parts ended up being inadvertently machined from the nasty mystery brass that created so many problems for the crankshaft oil manifold.

I wanted the flanged fittings that were used at the rear of the engine to be as small as possible, but their mating surfaces needed enough area to provide leak-free joints. I didn't want to use sealer on any part of the oil system for fear of it finding its way inside a tube and creating a blockage. The tubes were soldered to the fittings with a tiny butane torch while they were bolted onto the engine in their final positions and with their sealing surfaces parallel and making full contact. The challenge while forming the complex bends was to not only make them pleasing to the eye but precise enough so they slipped easily into position.

Eventually, I created a custom union for the four lines on the starboard side of the engine just forward of the distributor and barely out of the way of its plug wires. Yet another set of fittings was machined to accommodate the bends coming out of the union. A really troublesome line needed to be run to the input fitting on the top of the wheel case. This single line created 90% of the rod and tubing scrap shown in one of the photos. The union isn't rigidly attached to the crankcase but is well supported and held in position by the four tubes attached to it. This was done to reduce the stresses on the solder joints. After all the oil lines were completed and finally in place, each was removed, one at a time, so linen paper gaskets could be added.

Those who have been following this build, and didn't like my brass relief valve housing, may not like the brass union either.

It's bigger than I would have liked, but it will be hidden behind the distributors and plug wires when they are installed. - Terry