5-cylinder radial

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Deva

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Hello All from Slovakia!

I started my second project. First was tiny glow engine Boll Aero 1.8.
(If somebody will be interested, i could add a few photos)

This time, it will be quite a big step forward - 5 cylinder radial engine 82cc

I bought plan from oficial website: www.cad-modeltechbik-jung.de

Recently I've done few parts as exhausts nuts, adjusting valve screws, Chuck cone... And I am waiting for 7075 aluminium for crank case.
 

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SPOTTER

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Congratulations a really nice and very demanding job,
Is the link where you bought the project not active?
thank you
 
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Deva, you are very able as a machinist. I don't have all the tooling nor the confidence to even attempt the crankcase you have already made!
WELL DONE SIR!
Keep on enjoying your hobby and posting stuff to make us smile.
I am currently struggling with an in-line steam pump. All straight lines and even that challenges me. To manufacture the pentagonal shapes you have made is not on my agenda. I doubt I could make 5 pistons the same!
K2
 

ajoeiam

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I am currently struggling with an in-line steam pump. All straight lines and even that challenges me. To manufacture the pentagonal shapes you have made is not on my agenda. I doubt I could make 5 pistons the same!
K2

Hmmmmmmmmmmmm - - - - that is why its a 'challenge'. You, too (!!!!), will be able to rise to that challenge do you choose to do so.
This is part of a skill set.
Making one part well could be viewed as a fluke or chance happening (don't think it is but - - - ???).
Making a series of parts well skill (and consistency) just needs to be there.
Making a set of pretty much identical parts - - - - (very careful measurements with high accuracy tools will most often show very small differences) well - - - you have 'arrived' - - - - this could be viewed as a competency test in fact.

Suggest keeping on keeping on - - - don't think of what you 'think' you can't do.
Do the next thing you need to do and in time you will likely surprise even yourself (I am quite certain you could even make 18 parts (18 cylinder radial) all useful!!!
 
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Thanks AJ. I have made a few engines (from casting kits), and recognise the limitations of some of my tools. Having worked in industry (since I was 13 - part time when I started!) I appreciate the machine accuracy and limitations thereof. None of my machines are "perfect" - and my ability to compensate for those imperfections is far from perfect! While I know and have worked on the "setting" and "variation" of machining (from the desk, as an Engineer), the "skills of toolmakers" elude me. What I "think" I can achieve is usually beyond the final result, not the other way around.
But I do keep on keeping on. And I do what I enjoy, as this is a Hobby, not a business.
Knowing how difficult this Hobby can be for certain things, I do have a lot of admiration for those that achieve the models seen in the website. I post few pictures, as mine are "more warts than pretty bits".
Cheers!
K2
 

Deva

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Belive or not, 3 of my 4 milling machines was on they way to go to the scrapyard and, as I am addicted on chip making, had to change their destiny. So, non of my machines are perfect too. However I am triyng my werry best and enjoing transforming stock material into something that attract attention and interest. I am making a lot of mistakes and miscalculations during process, on the other side, all theese mistakes learn me how to make it better next time.

Still a lot to learn from you guys.
 

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Deva

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I found only a few free hours in toolroom during bussy summer days. Material used is C45, However I do not belive in it. Probably I will made a new one to satisfy myself, this time from 1.2312
 

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Looks good Deva!
I don't know your steel grades.... but a friend gave me an engine where the similar crank was made from what he thought was phosphor bronze. It wasn't, It was copper. The crank pin bent at the first firing run, but my steel replacement was OK. The drawing states C45. ?
K2so why do you think it is not up to the job?
You need fatigue resistance for a crank. Particularly with cantilever pin like yours.
Also, you must have all the corner radii required of the drawing, to avoid stress concentrations in excess of the design. Detail A does not show a min radius in the corner, what rad was on your tool?
But your work looks excellent, so I assume it is true to the drawing, so should be OK? - if the design is proven...
K2
 

Deva

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Looks good Deva!
I don't know your steel grades.... but a friend gave me an engine where the similar crank was made from what he thought was phosphor bronze. It wasn't, It was copper. The crank pin bent at the first firing run, but my steel replacement was OK. The drawing states C45. ?
K2so why do you think it is not up to the job?
You need fatigue resistance for a crank. Particularly with cantilever pin like yours.
Also, you must have all the corner radii required of the drawing, to avoid stress concentrations in excess of the design. Detail A does not show a min radius in the corner, what rad was on your tool?
But your work looks excellent, so I assume it is true to the drawing, so should be OK? - if the design is proven...
K2
Hello !

Yes, drawing states C45. In USA it is standard: ASTM A29 Grade: 1045
 
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It's not age that deteriorates things (lathes and bodies) but wear and tear.... Unfortunately (?) Cast iron lathe beds suffer both wear and tear and corrosion, but ageing is much slower... (compared to humans, plastics, and other organic compounds!). Cars used to be scrapped for rust, but my last car was "moved on" as the accountants'valuation was getting too low, and cost of lots of rubber stuff was getting too high for me to need to replace all the bits. It is now the "organic stuff" that is ageing and scrapping cars, not the metal bits.
Your lathe is pre-organic and pre-electronic technology.
My lathe isn't. At 15 years old, the motor, speed controller, and other electricals have had "organic bits" and "electronic bits" replaced... but the cast iron bits are near perfect!
Lucky you!
K2
 

Deva

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It's not age that deteriorates things (lathes and bodies) but wear and tear.... Unfortunately (?) Cast iron lathe beds suffer both wear and tear and corrosion, but ageing is much slower... (compared to humans, plastics, and other organic compounds!). Cars used to be scrapped for rust, but my last car was "moved on" as the accountants'valuation was getting too low, and cost of lots of rubber stuff was getting too high for me to need to replace all the bits. It is now the "organic stuff" that is ageing and scrapping cars, not the metal bits.
Your lathe is pre-organic and pre-electronic technology.
My lathe isn't. At 15 years old, the motor, speed controller, and other electricals have had "organic bits" and "electronic bits" replaced... but the cast iron bits are near perfect!
Lucky you!
K2
Steamchick, you are rigt! ;-)

Belive or not, cost of this lathe was less than your cell phone, thats the reason of my happiness. Lathe was running few years in a small company at the edge of town, old man which work on it died 8 years ago, and they have no one to replace old craftsman, so decided to send it to the scrapyard. Luckily, my friend worked as a serviceman for welding machines in that company so gave me echo.
Due to only bewel gears it's a bit louder, however able to turn bar up to weight of 2600lb, and with a wide variety of thread cutting. And also small things up to 1400rpm
 

Deva

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My first project: Boll Aero 18

Winter comming soon, will be time to find any wings for it.
 

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