Author Topic: Mercedes-Benz W165 Grand Prix engine in 1:3 scale  (Read 63505 times)

Offline nj111

  • Full Member
  • ****
  • Posts: 58
Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #285 on: March 30, 2020, 10:29:14 AM »
That's great! Thank you for the update
Nick

Offline Vixen

  • Full Member
  • ****
  • Posts: 1651
  • Hampshire UK
Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #286 on: March 30, 2020, 11:46:04 AM »
Hello Simon, Art, Nick and everyone else

Thanks for calling in and for looking in.

I had not intended to return to the Mercedes W165 until mid summer at the earliest. I had hoped to meet up with the Mercedes historic car people at the Goodwood Festival of Speed in July, or during the week after, before they returned to Stuttgart. I had hoped to talk them into releasing some more photos of the rear of the engine, particularly the cam drive train.

But the world changed overnight and all plans for 2020 have evaporated.

I have made a best guess at the design of the camshaft gear train based on what little information I have collected together over the years. Some things are know. The camshafts have 64 teeth gears, therefore the crankshaft and magneto drive must therefore have 32 teeth pinions. The idler gears between, can have any number of teeth, that does not affect the 2:1 reduction. However the idler gear wheel size is dictated by internal clearances and the need to pass through the ring of bolts holding the clutch housing in place. I modeled my 'best guess' gear layout in perspex on the back of the model and it appears to be a logical design. I cannot confirm it's correctness. Even so, I will proceed with what I have. The next step is detail design drawings, which should keep me indoors and busy for a while.

How far can I get? That all depends on the supply of raw materials. I had not planned to start so soon, so I have not bought in the required stock to complete the job, I will try to make do with what is available, but I don't have a large materials collection.

Stay in, stay safe

Mike
It is the journey that matters, not the destination

Offline Johnmcc69

  • Full Member
  • ****
  • Posts: 620
  • Erie Pa., USA
Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #287 on: March 30, 2020, 02:29:25 PM »
Beautiful work Mike!

 John

Offline Twizseven

  • Full Member
  • ****
  • Posts: 415
Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #288 on: March 30, 2020, 02:51:25 PM »
Stunning Work.   :praise2: :praise2: :praise2:

Colin

Offline Vixen

  • Full Member
  • ****
  • Posts: 1651
  • Hampshire UK
Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #289 on: April 01, 2020, 03:55:58 PM »
The design of the cam drive train for the Mercedes W165 will be challenging as I do not have any detail drawings or photos of the rear of the engine. Mercedes Benz corporate policy is not to give such information away as it could assist unauthorised counterfeit reproductions of their products to be built.

So be it.

Fortunately, I did find this photo of the back face of a V12 W153 in the Louwman Museum, Holland.  It provides a good indication of how the Mercedes engineers designed these parts back in 1938. You can clearly see the camshaft drive train was enclosed in a narrow cast alloy box with external bosses to support the bearings for the individual gears in the gear train. Although the gear layout is different to the W165, I believe it gives a good idea what it should look like.




I believe it is asking a lot to get the centres of all 10 gear centres in the correct position to give perfect meshing. Instead I decided to mount the two pairs of intermediate idler gears on two separate bridge pieces. This is in some ways similar to the bridges used on watches and precision time pieces. The positions of the  intermediate idler gear pairs can be adjusted until a perfect mesh is achieved then bolted firmly in position. The bridge pieces will be bolted to bosses protruding from the engine side, half of the gear case. The intermediate gears and bridge pieces only attach to the front half casing, there will be no connection to the rear casing The rear half of the gear casing will bolt to the front half and will carry cosmetic, non functioning external bearing bosses over the individual gear positions.




Well that's the plan. I have steel bar for the idler gears on mail order. So if it ever arrives, I will start my making the idler gears and bridge pieces, which can be tested against my perspex mock up.

Stay in, stay safe

Mike
« Last Edit: April 01, 2020, 09:55:33 PM by Vixen »
It is the journey that matters, not the destination

Offline fumopuc

  • Full Member
  • *****
  • Posts: 2563
  • Munich, Germany, EU
Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #290 on: April 01, 2020, 04:10:17 PM »
Hi Mike,
that seems to be a brilliant idea to get it proper and a bit flexible done.

Kind Regards
Achim

Offline Roger B

  • Global Moderator
  • Full Member
  • *****
  • Posts: 4331
  • Switzerland
Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #291 on: April 01, 2020, 05:29:58 PM »
That's a complicated gear train  :headscratch:  :headscratch: and a good solution  :wine1:

I guess that the shaft in the middle of the picture is the steering column?
Best regards

Roger

Offline Vixen

  • Full Member
  • ****
  • Posts: 1651
  • Hampshire UK
Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #292 on: April 01, 2020, 05:34:27 PM »
I guess that the shaft in the middle of the picture is the steering column?

That's correct. Perfectly designed to impale the driver's rib cage in the event of a collision.

Mike
It is the journey that matters, not the destination

Offline cnr6400

  • Full Member
  • ****
  • Posts: 613
Re: Mercedes-Benz W165 Grand Prix engine in 1:3 scale
« Reply #293 on: April 01, 2020, 08:21:45 PM »
Ah, the old sternum-werfer, eh?