Mills 1.3

[Ghosty]

Hi All,
I looked into making a Mills 1.3 engine as they are getting very hard to get.
Found a web site with plans https://outerzone.co.uk/plan_details.asp?ID=13735
Printed the plans out and studied for a few hours. Have found many mistakes in downloaded plans in the past.
Found a mistake, width of the starter block for the crankcase was marked at 1-9/16" wide. on plans the width of the crankcase is total of 1.654" a difference of 0.0915".
After double checking dimensions, I checked on what I had at hand. I had enough to get started with.
First got the material cut, then squared up and sized the block for crankcase.
Then marked out and drilled 4 holes for the mounting lugs, then drilled and tapped the 4 holes for the cylinder mounting.
Will move on to crankcase machining tomorrow.
Cheers
Andrew

[Kim]

Looks like a fun little engine to make.  Hopefully, the errors in the drawings won't be too much of a distraction.   

Kim

[Ghosty]

Hi All,
Started the machining of the crankcase, setup, trued and centered, machined crankshaft pocket and bore, and threaded for backplate, thread is listed at 26TPI, as I can't cut imperial threads on my lathe, I used a 1mm pitch and the dia listed on the plans.
Then rotated the case, trued and centered then machined the cylinder bore.
Then moved to the mill, machined conrod relief, exhaust ports, and transfer port.
Will now move on to machining the outside or the case.
Cheers
Andrew

[Admiral_dk]

Looks like a good start to a fine little Classic Engine 

Will follow with interest     

Per

[Roger B]

That's off to a good start    I will be following along 

[Ghosty]

Hi All,
Got on with the outside of the crankcase/body.
Started with the base/engine mount lugs, then the top sides, then cut the sides to the angle.
Then machined up two jigs to hold the case to machine on the lathe.
Machined the nose of the case and then on to the mill again to machine the base of the case.
Then glass bead blasting to get the finish on the case, then back on the lathe to do the final machining(sorry no pics of machining) of case.
Great care is needed when you do this step so you don'y drive the tool into the case.
Cheers
Andrew

[Ghosty]

Some more

[Ghosty]

Hi All,
P.S. Remounted crankcase to show final cutting of case. tool post compound set at 7deg for cutting.
Access for grub screw is through the crankshaft pocket.

Cheers
Andrew

[crueby]

Excellent job on those parts!  The bead finish looks great!

[Ghosty]

Thanks, crueby, the finish that I get from doing this also hi-lights the machined section
Cheers
Andrew

[Admiral_dk]

Two great looking Crank-/Engine- Cases/Blocks 

Very good progress in my book 

Per

[Don1966]

Nice work…..


 
Don

[Ghosty]

Hi All,
Worked on the cylinder today.
Machined the first end out of square bar, thread should have been 0.540" x 26TPI, I used M14x1(0.551") as I cant cut imperial threads on my lathe.
Then, with a bit of 19mm hex bar, I drilled and tapped M14x1 to use as a jig to hold the cylinder , so I can machine the other end.
I machined down the other end to fit the case body, then drilled and reamed to 0.406".
Then I started on the cooling cap. Drilled and tapped M14x1, and checked fit of cylinder.
Machined the cooling fins, parted off, tapped for compression screw, then machined compression screw and assembled.
Cheers
Andrew

[Ghosty]

And some more

[Roger B]

Excellent