Building a V12 crankshaft

Home Model Engine Machinist Forum

Help Support Home Model Engine Machinist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Pictures 129, 130, 132, 133 :
Drilling the oil channels is the last process requiring precision. As the crank journals are hollow, there will be no way to drill the various walls without the drill skewing and breaking. To solve that problem, you need to insert a mild steel « martyr » buffer (see picture 133). The buffer must be fixed using Loctite. This trick should enable you to drill the channels easily. LeZap




129.jpg


130.jpg


132.jpg


133.jpg
 
Pictures 134, 136,138,139 :
With the crankshaft completed, you now need to remove the templates located at the ends. Always use the under arm to minimize the flexion of the workpiece
LeZap

134.jpg


136.jpg


138.jpg


139.jpg
 
Picture 144 :
Check the run outs as well as the homogeneity of each crankpin, which must be below 0.2 mm on the central bearing.

Picture 146 :

To recover this run out, you need to set the crankshaft on the milling machine as shown in the picture. Place the crankshaft between two V-leveling pads and a brass axle to press the crankshaft. Zero the X-, Y- and Z-axis by just touching the central bearing. In order to minimize the stress on the piece, it is recommended to heat it in an oven (220°C, 20 min). Once the piece is hot, place it under the milling machine and start with a 1.0 mm deformation. Remove the piece and check with a Pupitast indicator. As the piece must not cool down, put it back in the oven regularly. Deformation can be gradually increased, but only by 1.0 mm at a time, and up to a maximum of 5.0 mm. A residual deformation of two to three percents is acceptable.
LeZap

144.jpg


146.jpg
 
This is simply a work of art you have there!

Are you going to make the rest of the Merlin or are you stopping at the crank?

Keep up the fantastic work!
John.
 
If the crank is finished then you should start a "work in progress" thread on the rest of your beautifull engine. After you finish posting about your crank of course. Thm:

Cheers,
John.
 
Pictures 156, 162 :
Crankshaft finished. Final weight 777gr (7000gr at the beginning)
125 direct labor hours and 80 hours of indirect work such as: creation of a grinding machine, specialized tools, jig bearings, etc...
LeZap

156.jpg


162.jpg
 
125 direct labor hours and 80 hours of indirect work such as: creation of a grinding machine, specialized tools, jig bearings, etc...

And people wonder why one-off's cost so much! :wall:

Nice work....I will be waiting for the upcoming portion.
 
Hello there,
I present to you my last work. It's the crankshaft ot the Rolls-Royce V12 Merlin at scale 1/4.
In the followed weeks, I will post the building process with needed pictures
LeZap

View attachment 56977

View attachment 56978
Hello, my name is Sun Guangye from China. Your work has shocked me. I want to be as good as you, but first of all I want to buy Rolls-Royce v12 engine. I don't care if it can be done. I love it. Please fulfill my little wish. Please
 
What a work of art! I've just destroyed my my second attempt at the tiny inline four crankshaft this weekend. Your pictures have motivated me to try a third attempt.

Fantastic detailed write up and photos.
 

Latest posts

Back
Top