Ohrndorf V12, new challange

[fumopuc]

Very nice!

Michael, Danke.

[fumopuc]

Next to do, to fit the gear to the shaft.
First disassembly one side.
Making at set up at the conventional mill to drill a hole into the shaft and gear.
Than preparing the stack and giving some Loctite 648 to it also, before the arbor press has quizzed it together with the relevant bearing shield in the sandwich.
Drilling and reaming the next steps in the earlier mentioned set up, with the help of a collet block.
Also here some Loctite 648 to support the fit of the 2 mm pin.
And a reassembling.
At the other side, where we have the two pins in the shaft, I will secure the pins in the same way, to be sure that they will not move into the rotating conrod.

[steamer]

Thats coming along fantastic!    Watching along   especially with the cylinders!....

Dave

[Art K]

Achim,
Really good work making and assembling the crank! And that it spins as it should is great.
Art

[fumopuc]

Thats coming along fantastic!    Watching along   especially with the cylinders!....

Dave

Hi Dave, thanks for watching.
Yes cylinders are next, but before I have to solve the con rod collision issue.

[fumopuc]

Achim,
Really good work making and assembling the crank! And that it spins as it should is great.
Art

Hi Art, thanks for popping in.
Spinning crankshaft is really a big success, but I have to get it out again.

[fumopuc]

Hi everybody, I thought a stand for the engine could be useful.
Easy way, made from some Aluminium  bar stock 20x20x3.

[fumopuc]

Some time ago, I have shown the CAD simulation of the con rod collision with the crankcase.
https://www.modelenginemaker.com/index.php/topic,11829.msg280985.html#msg280985
And Peter (petertha) has pushed me in the right direction, to have a look at all critical areas there.
https://www.modelenginemaker.com/index.php/topic,11829.msg281039.html#msg281039
Now, before I want to do the final assembly of the crankshaft it seems to be the right point to attack this collision issue.
The recommendation of Mr Ohrndorf, to use a file is for me at bit to "not proper defined".
So I started a  investigation in the CAD model first inner side in the V.
I have developed a for me easy way of reworking all this relevant places.
Also at the outside.
tbc...

[fumopuc]

I will do it with the conventional mill and a 3 mm cutter.
The fixture used at the CNC mill for making the crankcase will used again.
A quick check with printed dummy has shown no need for a big "cleaning" at the table of the BF20 necessary.
Disassembly, alignment, and adjusting the right angle, as simulated in CAD.
Enough free space to enter there from the top.
tbc...

[fumopuc]

Also at the other, the outer side.
A picture of my hand written "G-code" also.

With my remaining set up parts from the webs and con rods manufacturing I have made a quick and dirty sample assembling.
The cut outs seems to be there, where they should be.
Next, to check if is really OK there now and all collisions are sorted out.
tbc..
 

[fumopuc]

The real cylinders, liners and pistons are not available so far, so I have made a 3D printed dummy/spacer, for my 3D printed version of a cylinder without a liner.
This spacer should keep the small eye of the con rod at its real place, if the con rod is in the critical position with the former collision point.
The pictures of the hard ware are a bit useless, because I didn´t get it managed that my auto focus will catch it properly.

Never the less, light is seen and space it also there, even if I can not show it here.
So I think this problem is solved now.
The last pictures does show all the rework places, marked in red.

[Kim]

Nicely done, Achim!  Nice solution to the interference issue. 

And I like the inventive use of the 3D printed spacer gizmo to help determine if your interference fix worked. That was really slick!

Kim

[Admiral_dk]

Nice solution + really good to solve it before something nasty happens 

Per                

[fumopuc]

Nicely done, Achim!  Nice solution to the interference issue. 

And I like the inventive use of the 3D printed spacer gizmo to help determine if your interference fix worked. That was really slick!

Kim

Hi Kim, thanks.
This morning when I woke up, I have felt not comfortable with the check of only one cylinder bore so fare.
So decision made to do it with all.

[fumopuc]

Nice solution + really good to solve it before something nasty happens 

Per                

Hi Per, thanks.
Yes, good opportunity to make it here and now.