Build My Own Engine

Old 01-21-2015, 11:08 AM
  #1  
Tech Master
Thread Starter
iTrader: (4)
 
Jaymancd's Avatar
 
Join Date: Jul 2013
Location: in my house
Posts: 1,368
Trader Rating: 4 (100%+)
Default Build My Own Engine

Hi all. I have the opportunity to make my own engine as a project for a C.A.M. class that I am enrolled in. I was wondering if anyone knew when looking at the front of the flywheel while on the engine, wether the engines run clock-wise or counter-clock-wise. I plan on using a CNC machine for most of the work and making of the parts but just needed to know the direction the engines turn. Also on this question, How do I make sure it starts and runs the right direction. Thanks
Jaymancd is offline  
Old 01-21-2015, 11:11 AM
  #2  
Tech Regular
iTrader: (1)
 
ctsvls2's Avatar
 
Join Date: Feb 2014
Location: Seabrook. TX
Posts: 331
Trader Rating: 1 (100%+)
Default

Originally Posted by Jaymancd View Post
Hi all. I have the opportunity to make my own engine as a project for a C.A.M. class that I am enrolled in. I was wondering if anyone knew when looking at the front of the flywheel while on the engine, wether the engines run clock-wise or counter-clock-wise. I plan on using a CNC machine for most of the work and making of the parts but just needed to know the direction the engines turn. Also on this question, How do I make sure it starts and runs the right direction. Thanks
Should start and run whatever direction you turn it with the pull start or starter box...I assume.
ctsvls2 is offline  
Old 01-21-2015, 11:12 AM
  #3  
Tech Master
Thread Starter
iTrader: (4)
 
Jaymancd's Avatar
 
Join Date: Jul 2013
Location: in my house
Posts: 1,368
Trader Rating: 4 (100%+)
Default

Ok I just wasnt sure because I have had engines run backwards and it doesnt work real well.
Jaymancd is offline  
Old 01-21-2015, 11:15 AM
  #4  
Tech Adept
 
RobinCH's Avatar
 
Join Date: Feb 2013
Location: Lucerne, Switzerland
Posts: 117
Default

If this were another board I'd think you're trolling... ;D
Most nitro engines run clockwise, so looking at the flywheel from the front counter-clockwise.
The only directional part is the crankshaft as far as I know which is optimised for the direction it's running. They can run in both directions though, but will run much better in the correct one.
As for starting, you turn it into the right direction with a starter box, pullstart or some other contraption and you make sure it doesn't ignite too early which could lead to it turning in the other direction.
Is it just a CAD project or are you going to produce anything? If it's the latter then get some experience with existing engines first (10 years should suffice... ;D )
RobinCH is offline  
Old 01-21-2015, 01:00 PM
  #5  
Tech Master
Thread Starter
iTrader: (4)
 
Jaymancd's Avatar
 
Join Date: Jul 2013
Location: in my house
Posts: 1,368
Trader Rating: 4 (100%+)
Default

Ok, thanks for the info. First it is just going to be a CAD project but may grow into something more. We will see depending on if I can get it to work right.
Jaymancd is offline  
Old 01-21-2015, 01:08 PM
  #6  
Tech Master
Thread Starter
iTrader: (4)
 
Jaymancd's Avatar
 
Join Date: Jul 2013
Location: in my house
Posts: 1,368
Trader Rating: 4 (100%+)
Default

Along this same line, is the different engine sizes, like .21 .28 .18 and so on, are these numbers the displacement of just the piston, or is it the piston sleeve con rod and crank?
Jaymancd is offline  
Old 01-21-2015, 01:34 PM
  #7  
Tech Regular
iTrader: (1)
 
Imbue's Avatar
 
Join Date: Nov 2012
Location: Fairhope, AL
Posts: 460
Trader Rating: 1 (100%+)
Default

Designing an engine that will run is rather easy. Just get any engine and reverse engineer it. The majority of today's .21 engines are all reverse-engineered off of each other and have become homogenized for the most part.

If you ever make it to prototyping, have a look at the early BP Racing engines. They used a 100% CNC'd engine case. This is basically going to be how you have to design your engine, as I doubt the school is willing to fund a diecast injection machine, and molds ($$$).
http://www.neobuggy.net/2006/11/01/1313/
Imbue is offline  
Old 01-21-2015, 01:51 PM
  #8  
Tech Champion
 
Roelof's Avatar
 
Join Date: Aug 2007
Location: Holland
Posts: 8,350
Default

Originally Posted by Jaymancd View Post
Ok I just wasnt sure because I have had engines run backwards and it doesnt work real well.
The crankshaft timing is causing this. If the timing of opening and closing was symetric then the motor will run in both ways the same (based on glowplug ignition).

I have a list of timings on my website and also First-racing.eu has a large list, all based on engines running anti clockwise as seen from the front.
This is no problem to create, the biggest issue wiil be getting matching materials for the sleeve and piston. If the expansion do not match you can get a bad performing or even a bad running engine.
Roelof is offline  
Old 01-21-2015, 08:50 PM
  #9  
Tech Master
Thread Starter
iTrader: (4)
 
Jaymancd's Avatar
 
Join Date: Jul 2013
Location: in my house
Posts: 1,368
Trader Rating: 4 (100%+)
Default

The website didnt work for me. Could you post a link? I would really like to try this
Jaymancd is offline  
Old 01-22-2015, 01:32 AM
  #10  
Tech Champion
 
Roelof's Avatar
 
Join Date: Aug 2007
Location: Holland
Posts: 8,350
Default

http://www.euronet.nl/users/tooms/timings/timings.htm

Direct link to my page about engine timings and on that there is a link to first racing.
Roelof is offline  
Old 01-22-2015, 06:14 AM
  #11  
Tech Master
Thread Starter
iTrader: (4)
 
Jaymancd's Avatar
 
Join Date: Jul 2013
Location: in my house
Posts: 1,368
Trader Rating: 4 (100%+)
Default

Thanks.
Jaymancd is offline  

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.