Author Topic: Mercedes-Benz W165 Grand Prix engine in 1:3 scale  (Read 151603 times)

Offline Admiral_dk

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Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #630 on: February 19, 2022, 09:24:37 PM »
I have noticed too, but didn't dare mention as there can be so many reasons why - like going back to round engines, tank engines and gearboxes, lack of interest for a while, health etc. ....

Great to see it assembled even more  :cheers:

Per

Offline Craig DeShong

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Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #631 on: February 19, 2022, 09:50:44 PM »
With all those beautiful gears fitted and turning freely, it's time to start covering them up.

NOOOOOOOOOOOO! you can't do that; even if it's called for by the full size  :(

I was wondering about the hiatus; glad it was short and we get to see more progress on this magnificent model.
Craig
The destination motivates us toward excellence, the journey entertains us, and along the way we meet so many interesting people.

Offline steamer

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Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #632 on: February 19, 2022, 10:18:03 PM »
Still here friend! Your work is always beautiful!
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Offline Laurentic

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Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #633 on: February 20, 2022, 10:35:32 AM »
Really beautiful work Mike, made all the more fantastic by your daughters insistence of element of scale, seeing just a photo it's easy to think it's a much bigger engine than it really is, seeing it tiny on your daughters lap makes all that detailed and precision work even more wonderful to contemplate.

Great job.

Chris   :cheers:

Offline steamer

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Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #634 on: February 20, 2022, 10:58:44 AM »
Crankshaft!  Crankshaft! Crankshaft! Crankshaft!........... :LittleDevil: 8)
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Damned ijjit!

Offline kvom

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Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #635 on: February 20, 2022, 01:49:01 PM »
Love it!

Offline Roger B

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Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #636 on: February 21, 2022, 07:37:16 AM »
Excellent  :praise2:  :praise2:  :wine1:
Best regards

Roger

Offline Zephyrin

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Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #637 on: February 21, 2022, 08:56:01 AM »
Really amazing work on all these parts and the assembly, up to the surface finish softly reflecting daylight, everything is incredible !

Offline Vixen

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Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #638 on: February 21, 2022, 12:09:11 PM »
Thank you all for your generous comments and encouragement. They are all very much appreciated.

During the winter months, I find less and less desire to go out into the cold and wet to get to the workshop at the bottom of the garden; the arm chair in front of the fire is much more appealing. From now onward, the weather should improve and progress can be made once again.

Last year I invested in a large bucket of glass bead blasting media to replace the previous alumina grit media. The difference was immediately obvious. The glass bead media produces a fine, smooth, finish which softly reflects the daylight whereas the alumina grit surface was rough, which attracted dirty finger prints.  Also, the alumina grit produced lots of dust within the cabinet and the work had to be done outdoors; it also lost effectiveness with time. By contrast, the glass bead media produces no dust and the media appears to be undamaged and can be used again and again.

Cheers :cheers:

Mike

« Last Edit: February 21, 2022, 01:23:31 PM by Vixen »
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Offline BillTodd

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Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #639 on: February 21, 2022, 05:07:14 PM »
Well worth getting some dust extraction when using glass bead. Dust may not be apparent but silicon is particularly nasty stuff to breath in.


Lovely work on that engine BTW 8-)

Bill

Offline Vixen

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Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #640 on: February 21, 2022, 05:27:43 PM »
Well worth getting some dust extraction when using glass bead. Dust may not be apparent but silicon is particularly nasty stuff to breath in.

Bill

Thanks for the dust warning Bill. I have a vacuum cleaner connection on the side of the cabinet. However the noise of the vacuum cleaner and the compressor going flat out is deafening.  :ShakeHead:  :ShakeHead:

Cheers

Mike
It is the journey that matters, not the destination

Sometimes, it can be a long and winding road

Offline Art K

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Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #641 on: February 23, 2022, 02:10:23 AM »
Mike,
Been there done that, my job includes sand blasting. Or rather I should say media blasting since we use glass beads. With the sound the vacuum system makes, compressor is outside it's quite loud. Great work! nice to see the assembly.
Art
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Offline Vixen

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Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #642 on: June 21, 2022, 01:36:56 PM »
Morning All,

It's been a while , I know, but I have at last found time to make a little progress on this long running build. Along the way, this thread has passed 100,000 views. so thank you all for tuning in so regularly.

I used the time to make a start on the two sets of con-rods. That's a total of 16 con-rods plus a couple more; just in case.

The full size Mercedes Benz engine used a one piece hardened steel crankshaft and two piece hardened steel con-rods running with caged roller bearings. The roller bearing for both the big ends and main bearings run directly against hardened con-rod and crankshaft surfaces.

Here is a photo of a similar con-rod (it's from a full size replicas MB W125 engine). You can see the elaborate split line necessary to achieve prefect alignment of the two halves of the big end bearing. The replica con-rods were machined from solid, nitride hardened and then ground and polished to create the roller bearing surface. The full size crankshaft was also machined from solid, nitride hardened with all the journals ground and polished to size.





I chose to do it differently; I will use one piece con-rods and a built up crankshaft. I do not have the means to harden, nitride and grind the con-rod eyes or the crankshaft bearing journals. Instead I created an alternative design to allow me to use commercially available thin section ball races for the eight big end bearings and also for the five main bearings.  With either design there would still a need for high precision. However, my alternative design, should be within the scope of my machinery. 

I chose a different poison to Mercedes Benz by following the Auto Union method of construction.





Commercial thin section roller bearings are pressed into the one piece con-rod, they will have dummy big end bolts, just for show. The available thin section roller bearing were a little larger in diameter than I would have liked, which forced the wall thickness of the big end eye to be slightly thinner than the original design. It was for this reason, I felt it necessary to compensate for the reduced thickness by going for the strongest available aluminium alloy, for my one piece con-rods. I went for 2014 (HE15), as being the most affordable high strength aluminium I could find.

I only had a limited amount of the 2014 material to play with. It's much more expensive than 'ordinary' aluminium plate so I had to settle for an off-cut from my supplier. It was necessary to nest the con-rods on the stock to make maximum use of the available material. My table movement is a little under 8" x 4" but I found that it was possible to extract 8 con-rods from one piece of 8 x 5".

Here you can see the first operations. The stock plate was bolted to a jig plate, above a sacrificial stand off, which allows for bolt clearance. The top row of con-rods were machined to the first stage before the plate was rotated through 180* and the machining process was repeated. I used a boring head to bring the con-rods big end eye to the precise diameter, after first roughing out the hole by CNC




Top hat buttons were machined and used to secure and locate the big end while the individual con-rods were profiled and separated from the stock material.





Here you can see the tool path used to machine the outer profile of four con-rods at a time. And below that, the first set of four con-rods released for the stock plate. I used my peristaltic 'no mist' mister to deliver a tiny amount of water soluble coolant and blow the chips away from the action.






After that, what was left of the stock plate was turned though 180*, bolted back on the jig plate to machine the second set of four con-rods. There was very little wasted material left because of the close nesting.




I had set off with the intention of making 16 con-rods plus two spares; just in case. Along the way one rod was lost; so I ended up with only 17. Here they are playing 'ring of roses' and 'piggy in the middle'.





The con-rod in the centre has been fitted with the thin section bearing (SKF 61802). You will notice I have used a sealed 2RS1 version of the bearing. All the big end bearings will eventually be replaced with open SKF 61802 R02 bearings, But there is far too much swarf about to do that at this early stage.

There's more to follow; so stay tuned

Mike


« Last Edit: June 21, 2022, 01:48:34 PM by Vixen »
It is the journey that matters, not the destination

Sometimes, it can be a long and winding road

Offline RReid

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Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #643 on: June 21, 2022, 03:17:14 PM »
It's great to see this project progressing again, Mike, I've been missing it! I always enjoy the background you offer regarding the logic behind the engineering choices you've made. And those conrods are definitely up to your usual beautiful standard. I:cheers:
Regards,
Ron

Offline Roger B

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Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #644 on: June 21, 2022, 05:53:08 PM »
Splendid  :praise2:  :praise2:  :wine1:
Best regards

Roger

 

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