Tom KayThanks Trumper. The plastic is paintable. To get a decent finish, it takes primer, and maybe a few coats to get past the sandy surface. I’ll definitely be painting the pieces, red is my current thinking, with black for smaller parts for contrast.
Tom.
Tom KayMike, hello. I use Rhino 4 and have the same issues as you. Once a model becomes too big or complex, Rhino seems to stop adding new parts. Fillets can be quite tricky, but maybe variable radius fillets would be part of your answer. Add control points along the edge of a solid, and then reduce the fillet in smaller areas. Tried this? Also, Brazil is a great tool to render wire frame models. My wife appreciated knowing exactly what our kitchen would look like before we built it.
I might be able to build some small parts for you, if space in a build permits. The surface finish is like a fine casting with our Selective Laser Sintering machine, and there are other liquid based 3D printers, plus the “glorified glue gun” FDM type. Please give me an idea of what part and what size.
Tom.
Tom KayThanks Gents.
The issue of cost is a real concern with these rapid prototyped parts, but I’m lucky in this case, because this is the machine that I run at work. I can’t print any item at any time, so I have to be patient and wait for a build that has enough spare room in it to place in my parts. I other words, I can’t ad to the cost of an existing build. I have informed management many times, that if I am building parts for actual customers, and there is leftover room, I’ll make parts, any kind of parts, rather than throw more plastic powder into the garbage. They seem fine with this understanding, and have asked me to build a variety of items for their own uses as well, including their kids school projects. I support this use of the machine. Better than discarding expensive, but used, powder.
I cannot sell any parts that I create. That would be a real conflict. But I can share any 3D models that I make, as they are created on my own spare time at home.
Stuart, I need an aftercooler box too. Not sure what approach I’ll take, but you might call Jack Hovey 209 274 4422 in California as he has a large cache of Merlin parts, including some junk ones. Burned heads, cracked Dash 3 aftercooler boxes. If you go this route, please tell me how it goes.
More updates as they happen. Cheers, Tom.
Tom Kay“New build Merlins are not a pipe dream.”
This is something I’ve wanted to see for ages, so I’m all for it. Truthfully though, I can’t see it happening very soon, or even at all. And this is after seeing lots of new parts, including Retro’s new cylinder heads. This sounds counter-intuitive, but there are thousands of parts in a Merlin (I’ve heard 11,000 parts, but can’t verify).
Also, despite appearances, I think there is still a ton of inventory, if it could only be accessed a little more easily. Take 51 Factory in California for example. Their Merlin inventory is staggering. Here’s a glimpse of some of their spare parts. http://51-factory.com/inventory.htm If you look at just one of the pictures, you’ll see dozens of cylinder heads on a single shelf. All of this came from Paul Szendroi, former operator of Universal Airmotive in Chicago. Looking at 51 Factory’s inventory pictures kinda reminds me of the last scene in the Indiana Jones movie, where the Ark of the Covenant is stored in some endless warehouse, with row-on-row of shelves.
This doesn’t even include what Dwight Thorne claimed was enough parts to build 200 complete Merlins, and another collection of major parts to make 200 more without all the tiny seals and small parts. Mike Barrow, who used to work with Dwight Thorne (of Mystery Aire) mentioned that Dwight’s widow is just sitting on this inventory, and won’t sell it. I have no idea what her current status is, but that’s the last info I have on the late Dwight’s Merlin stock. This was 10+ years ago.
I have no idea what Mike Nixon’s inventory is either, but they are still very active in Merlin restoration.
Despite buying a crankcase from Mike Barrow last year, I really don’t know how much usable stock he owns. Or Jack Roush.
As I see it, it’s a pretty tough sell to go into limited production to make all new Merlin engines. I’d heard the crankshaft dies exist, but I suspect that a machined billet crank would be much easier for low production numbers.
I would love to see new production happen. I just have my ongoing doubts, based on cost, demand, and existing inventory. Of course, it would be foolish to assume that we have seen our last new Merlin part, minor or major, as this is happening all around us.
Cheers, Tom.
Tom KayJ Boyle, Roush makes a fair number of Merlin parts, but not any of the larger castings. Here’s a list of what they do; https://www.roushaviation.com/parts-inventory just click on the individual parts in the list that appears.
SeaFuryFan, I can imagine all sorts of problems cropping up with any complex engine rebuild. Tight tolerances would be one of a whole shopping list. I seem to recall Rolls Royce using an alloy called hydaminium (plus a number) but Pete would know more about this than I do. I wonder if the Merlin would be better with some modern alloy of aluminum.
Sopwith, I’m pretty sure it’s Retro Track and Air that is making the new Merlin heads, not Maurice Hammond. Having not been within 3000 miles of either, I got it wrong.
Oxcart, I may have wrongly written to Retro and started with “Dear Maurice Hammond” which would have warranted a speedy deposit into the email junk basket. I suspect now that I never actually did write to Mr. Hammond, just to Retro.
So, nobody has the elusive additional pics of Retro’s new cylinder heads? Cheers, Tom.
Tom KayHmmm, I had it in my mind that Maurice Hammond was with Retro, or even the owner. I see that I’m wrong. He appears to be with a company called Eye Tech.
I’d like to see more parts of the Merlin made with whatever modern method is advantageous. When you consider the total number of parts in these engines, it would still be a horrendous cost to build a full engine. But, I’d buy a front seat ticket to watch the action.
Any more pics of Retro’s new heads?
Tom.
Tom KayHi SeaFuryFan;
No doubt, with the right will power and budget, Merlins could be produced today, but being practical, there would be a lot of components that are horribly costly. Crankshafts, gears, etc. I have no idea how Maurice Hammond is making these heads. Old fashioned methods or maybe some modern techniques, such as 3D printing the sand molds for casting?? I’ve written to him twice, indicating my interest in Merlins and his work, but no replies.
Using modern techniques would help. Once you have a CAD model of a cylinder skirt or head, you have lots of choices. Coming up with the model is the hard part. I’ve done a skirt, and am currently reverse engineering a port side head with the right software, but very fledgling software skills. Here’s a pic of the skirt I modeled, and even that took a while. The head is much harder.
HP1111, I hadn’t heard of this gender issue, but you might be right. I have seen pictures of men setting up the cores for casting the cylinder skirts, and that may have been in the Packard plant, Detroit. I can’t seem to locate the pictures of that at the moment.
Cheers, Tom.
Tom KayThis is thrilling. I would love to see 2 B-29’s in formation. I can’t begin to imagine the work that went into this (or the 2 Lancasters, can’t forget those).
Canuckistan, Tom.
Tom KayHi Stuart; This project is very interesting. Years ago, I might not have said that, it being “just” a chunk of a Spitfire, but I feel very differently now that my own reality has slapped me down a bit. No I won’t own an operational Spitfire, or even a Titan T-51 Mustang, but I’m still in the game with a static merlin restoration. It still grips my interest, which is why I understand the whole build-a-cockpit hobby.
Back to you; have you made the undercarriage pintles yet? Have you made tooling to create them? If not, you might consider rapid prototyping. This can be costly, no doubt, but it can be quite flexible, and possibly save time and money, if you can eliminate various steps. Direct Metal Laser Sintering can make metals parts in lots of alloys (although be ready for some post processing). If that is too costly, you could do a CAD model of whatever parts, have them 3D printed in polystyrene, and then pretend this is a wax pattern which most investment foundries will accept and pour. Lots of places in Canada and the US use this method now instead of traditional wax patterns. Sorry if I’m mentioning something you already know.
At some point I’ll post some pics of the Merlin Dual Drive (aka V-Drive) and the left side cylinder block, which I have 3D printed on a Selective Laser Sintering station. The parts are full size, in nylon, and quite strong. I’ll paint them, hopefully add various data plates, locking wires to the inserted nuts and bolts, and get them to the point where it’s hard to distinguish them from the real McCoy. My cylinder head CAD model is about half done, and should be ready to print in a couple months. I find it VERY challenging to do these 3D computer models, as there is quite a lot of near-organic shaping to the parts, especially the crankcase. Of course my engine will always remain a pure static display, as the actual internal parts are prohibitively expensive.
Excellent work Stuart, and please keep posting pics. Also, can you direct me to the other website you mentioned, where you perhaps have a more complete build log?
Robert Whitton, I haven’t seen your project before. Nice work, based on the 2 pics of the H-stab. Do you have a more comprehensive website?
Lastly, I like the fact that QldSpitty is offering 3D printed Spit (and other) bits. I think this is a nice modern alternative for those who want good looking parts for a project, but have problems making or finding them. The spade grip is the most recognizeable part to me. Ross, I am guessing that you don’t stock all these parts, but keep the CAD models in readiness to print? Any plans for other models, such as engine parts?
Cheers, Tom.
Tom KayI know you’ll get a lot of different opinions on whether the bombing of Hiroshima and Nagasaki was the correct action or not, but here’s mine (and I expect many may disagree).
With the potential massive loss of Allied lives, primarily American, in invading Japan, I believe that if the atomic bombs saved one single American or Allied life, then it was an acceptable decision to drop them. Oddly, it probably saved Japanese lives as well, when you consider the consequences of long, drawn-out fighting as the Allies approached their nation. If you look at the horrific costs to both sides, of fighting in the Pacific islands, leading up to establishing air bases for the B-29’s, the Japanese didn’t give up anything without a horrific fight.
I can’t even begin to comprehend the moment the flash went off, as thousands of souls instantly disappeared, and the sheer horror in the following seconds, hours or days, so my position from my comfy chair is an easy one. But I still feel that it was right to deploy the bombs. I also feel it’s equally right to fight hard, current day, to end the possibility of similar atomic destruction anywhere else on earth. Pretty tough though, to put the cork back in the bottle.
Tom Kay.
Tom KayI was not aware of who Scott Slocum is, but I have educated myself a bit on the web, since I watched this Mosquito video. This is one of the best air-to-air I have ever seen. It’s just beautiful, and so is the subject. One good feature, is the lack of an ongoing commentator, as the scene just speaks for itself.
Fantastic work, Mr. Slocum.
Tom Kay.
Tom KayThat David Niven film, “A Matter of Life and Death.” Was it also called “Stairway to Heaven” where he thinks he’s fallen out of a B-25 (or similar) and survived, and then gets to choose any figure throughout history to defend him in a trial, to determine whether he lives or dies?
Or are the 2 movies separate films?
Tom.
Tom KaySee, I knew it. I also like the B-17 landing scene in Tora, Tora, Tora ! Screeeeeechhhhh……..
Tom.
Tom KayHmmm, I like this thread. I can’t boil it down to one film sequence, so here’s a few, in no order:
1. The Great Waldo Pepper, most of the flim, but especially the outside loop attempt by Edward Hermann (really Art Scholl).
2. Flight of the Phoenix, engine start scene. “Alright Mr. Dorfman, start pulling !” Jimmy Stewart was always in charge; he just let Hardy Kruger think he was for a while.
3. The missile chase sequence in Behind Enemy Lines. High octane entertainment.
4. The missile tracking sequence in Dr. Strangelove, despite the inane special effects. Kubrick took goofy models hanging from strings and turned that into a very tense scene.
5. The Blue Max where George Peppard and Jeremy Kemp are flying under bridges until Kemp gets killed.
6. Did I mention The Great Waldo Pepper? The whole damn movie?
No doubt I’ll think of more as soon as I hit “Post Reply.” Tom.
Tom KayMore fantastic views into this engine. Thanks again, Matthias!
I would guess, based on the rather square shape of the cam lobes, that each lobe does double-duty with exhaust, then intake valves. Pretty slick design, and very clean looking. Again, as a newbie guess, I assume that square lobe shape allows a little valve lead, lag and overlap.
And it’s hard to tell, but it appears that there is no bearing material (like bronze) in the cam towers, where they hold the camshaft. The bearing material could be hidden inside, but if not, this is another fresh new surprise. This is why those high-resolution pictures are helpful, Matthias. Please, snap away !
Tom.
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