Mills MK1 Series 1 Scaled down to 0.56cc

[Rodrigo Castellanos]

Hi guys!
Having some time and some aluminium stock, decided to try a small Mills Crankcase...

 

[Rodrigo Castellanos]

sorry, found an early progress pics..

 

[Rodrigo Castellanos]

ok... seems that the case can be usable.... lets do some more parts....

 

[Rodrigo Castellanos]

some more work done... first pic shows a VA David Banks 0.5cc mills repro, but MK2 version...

 

[Rodrigo Castellanos]

now looks like a real engine!!
still need to fix some issues and clearances... working with a scaled down plans seems to be a challenge, as a lot of stuff must be fixed or calculated.. but is part of the fun.

 

[stackerjack]

Rodrigo, You have done a wonderful job with your Mills. It'll be good to see the finished engine (running?)
Jack

 

[Rodrigo Castellanos]

Rodrigo, You have done a wonderful job with your Mills. It'll be good to see the finished engine (running?)
Jack

I will do my best! My weaver is now ready again for a test run... after making a new crankshaft with a lot better fit...

 

[KenC]

Rodriguez. Don't forget that you cannot apply the same scaling factor that you used for all the parts, to the carb bore. For instance if you half all dimensions you would end up with 1/8 of the original displacement. Yet halving the carb bore gives just 1/4 of the choke area, so the choke area would be twice the area needed for the smaller engine. You need to do the proper calculation for your engine.

 

[SmithDoor]

Looks great
I looking to a small engine too.
https://www.homemodelenginemachinist.com/threads/any-one-building-small-engine.32805/
Dave

now looks like a real engine!!
still need to fix some issues and clearances... working with a scaled down plans seems to be a challenge, as a lot of stuff must be fixed or calculated.. but is part of the fun.

 

[Rodrigo Castellanos]

Rodriguez. Don't forget that you cannot apply the same scaling factor that you used for all the parts, to the carb bore. For instance if you half all dimensions you would end up with 1/8 of the original displacement. Yet halving the carb bore gives just 1/4 of the choke area, so the choke area would be twice the area needed for the smaller engine. You need to do the proper calculation for your engine.

Hi Ken!
Thanks for the info... i was thinking to take some measurements from my D.B. Mills, especially the carb bore to get a nice idea... anyway, the carb part will be the last one as i need a 5mm the a very fine pitch.. and i will order some dies and taps... so... a long wait

 

[Rodrigo Castellanos]

Looks great
I looking to a small engine too.
https://www.homemodelenginemachinist.com/threads/any-one-building-small-engine.32805/
Dave

Hi! is nice to see someone wanting to build something small... if you want, i can share you some plans i have. Regards Rodrigo

 

[Rodrigo Castellanos]

Now is time for a pic!

 

[SmithDoor]

Hi! is nice to see someone wanting to build something small... if you want, i can share you some plans i have. Regards Rodrigo

Yes I like see your drawings.

I am working on my drawings

I am working the compression ratio right now. I post formula in zip file.
Any help would great full on compression ratio

Dave

 

[KenC]

If anyone is interested in building small engines, it really depends upon what you call small. I only build diesels and spark ignition engines, and my ignition engines are never small. My first really small diesel built back in 1988 was an own design 0.15cc diesel. Picture attached. Then at one time having built a 1cc Weaver I just halved all dimensions and made a 0.125cc version that I called the "Weevil" 'cos it really was an evil little thing before I sorted it out. Picture of both attached. Then just last year I made a copy of the well known Clanford "Clan" of 0.24cc. A video of the first run of the Clan is here Picture of the engine and parts also attached. So do I qualify as a builder of small engines?
Ken

 

[SmithDoor]

I like the size of your engine
It is great size for the FAA rules.
Do you have drawings

Thank you
Dave

If anyone is interested in building small engines, it really depends upon what you call small. I only build diesels and spark ignition engines, and my ignition engines are never small. My first really small diesel built back in 1988 was an own design 0.15cc diesel. Picture attached. Then at one time having built a 1cc Weaver I just halved all dimensions and made a 0.125cc version that I called the "Weevil" 'cos it really was an evil little thing before I sorted it out. Picture of both attached. Then just last year I made a copy of the well known Clanford "Clan" of 0.24cc. A video of the first run of the Clan is here Picture of the engine and parts also attached. So do I qualify as a builder of small engines?
Ken

 

[KenC]

Which engine, the 0.24cc Clan in the video?
Ken

 

[KenC]

The drawings for the little Clan are in my book "Motor Boys International, members only plans" which is a free download at rclibrary.co.uk and also is available on Adrians Model Engines web site. There are other plans in my book that may be of interest.
Ken

 

[Rodrigo Castellanos]

If anyone is interested in building small engines, it really depends upon what you call small. I only build diesels and spark ignition engines, and my ignition engines are never small. My first really small diesel built back in 1988 was an own design 0.15cc diesel. Picture attached. Then at one time having built a 1cc Weaver I just halved all dimensions and made a 0.125cc version that I called the "Weevil" 'cos it really was an evil little thing before I sorted it out. Picture of both attached. Then just last year I made a copy of the well known Clanford "Clan" of 0.24cc. A video of the first run of the Clan is here Picture of the engine and parts also attached. So do I qualify as a builder of small engines?
Ken

Hi Ken!

What a beautiful engines!!!!
love that mini Weaver! seems to be a real pain to work with that tolerances!
I had build a Weaver, with no results yet.... still not running... i just finished my 2 crankshaft and my 3th piston with bad results... new everything seems to be just fine... but the gudgeon pin hole in the piston was to big, making the case vacuum changing the time.... so i think is drinking fuel 2 times!!! can be posible??

kind Regards
Rodrigo

 

[SmithDoor]

Drawings from Motor Boys will be helpful.

Thank you
Dave

The drawings for the little Clan are in my book "Motor Boys International, members only plans" which is a free download at rclibrary.co.uk and also is available on Adrians Model Engines web site. There are other plans in my book that may be of interest.
Ken

 

[Rodrigo Castellanos]

Hi Dave! I have the files from motor boys book I and II, can you give me your email?

kind regards
Rodrigo