Go Back  RCU Forums > RC Boats > Speed - RC Nitro Boats
Reload this Page >

Spinning a tuned pipe.

Notices
Speed - RC Nitro Boats For all your rc nitro fuel burning boating needs.

Spinning a tuned pipe.

Old 08-16-2007, 12:20 AM
  #1  
youdirtyfox
Senior Member
Thread Starter
 
youdirtyfox's Avatar
 
Join Date: Jul 2007
Location: , UNITED KINGDOM
Posts: 143
Likes: 0
Received 0 Likes on 0 Posts
Default Spinning a tuned pipe.

Hi All,

As I work as a metal spinner, thought I may have a go at spinning my own tuned pipe for my aqua jet!
Anyone have any breif dimensions for me to work too. Obviously I think some racers will be keeping their
cards close to their chest's wich is fair enough if you've spent time out in the field researching pipe size's etc.
and spend money on different pipes etc!

Just wondering if thin or thick wallled ali is best an how the pipe should lay in the boat. Does it need to go cross ways to
give good weight distribution?

Cheers
Sam.
Old 08-16-2007, 02:48 PM
  #2  
4X4FABGUY
 
Join Date: Feb 2006
Location: KENNEWICK, WA
Posts: 44
Received 0 Likes on 0 Posts
Default RE: Spinning a tuned pipe.

Hi Sam, whats a metal spinner do? do you mean lathe work? just wondering. what size engine is in your aqua jet.
Old 08-16-2007, 03:37 PM
  #3  
youdirtyfox
Senior Member
Thread Starter
 
youdirtyfox's Avatar
 
Join Date: Jul 2007
Location: , UNITED KINGDOM
Posts: 143
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Spinning a tuned pipe.

Hi, yes it's mostly lathe work, by hand and by pneumatic (PNC lathe) PNC for heavy gauge stainless steel(10mm +!) and hand spinning for 1-2mm aluminiuim
and mild steel

Some of our work below
http://i23.photobucket.com/albums/b3...ABCD0006-1.jpg
http://i23.photobucket.com/albums/b3...m/DSC00155.jpg - brake vent I made for my car
http://i23.photobucket.com/albums/b3...m/DSC00128.jpg - My polishing [8D]


In the aqua jet is a cen .16 .


Cheers
Sam.
Old 08-17-2007, 02:26 PM
  #4  
Pete48
Member
 
Join Date: Aug 2007
Location: PresqueIsle, MI
Posts: 73
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Spinning a tuned pipe.

WOW! Nice work there. Very cool! I assume the pipe will need to be 2 pieces?

We used to tune pipes specifically for the RPM application. If you want low speed power, the pipe needed to be long and vice versa for high speed. If I understand it correctly, the shock wave leaving the exhaust port hits the end of the pipe and bounces back towards the engine and stuffs more fuel mixture into the chamber just before it compresses and fires. If you are running real high piston speed, the wave needs to get back in a hurry (short pipe). If you are running low piston speeds, the wave needs to kill some time, so the pipe is longer. Not too sure aout exact dimensions though! Would be interesting to calculate if we new the top end RPM's of the motor during full speed.
Old 08-17-2007, 07:16 PM
  #5  
youdirtyfox
Senior Member
Thread Starter
 
youdirtyfox's Avatar
 
Join Date: Jul 2007
Location: , UNITED KINGDOM
Posts: 143
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Spinning a tuned pipe.

Big thanks to Fabguy for the PM and Pete for the info and appreciation of my work

Yeah there are a few ways it could be tackled, two piece would be alot easier, but one piece is acheivable with the right tooling, wich could be quite expensive
However there are a few little tricks I've learnt over the years

Thanks again
Sam.
Old 09-06-2007, 06:04 PM
  #6  
Will Sgarlat
 
Join Date: Nov 2002
Location: Centerville, MA
Posts: 217
Received 0 Likes on 0 Posts
Default RE: Spinning a tuned pipe.

Hi mr. spinner,
By all means go for it! I use to work pewter and spun my share of traditional pewter ware and thought of spinning an aluminum pipe, too! I am really old school in this and used progressive forms to transform the flat disc to the finished product and this required a lot of lathe work to make the forms...are you spinning in the air??
OK so you spin the two cones then would you turn them so you have a uniform thickness, then weld them?
Definitely give us pics of your progress!
Will
Old 09-07-2007, 03:56 PM
  #7  
moparbarn
 
Join Date: May 2007
Location: winchester, va. VA
Posts: 176
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Spinning a tuned pipe.

sam-check out intlwaters.com. in the general boating forum is a good thread on tuned pipe volumes. a lot of good links to pipe design programs. plus, some VERY knowledgable people. they might be interested in your work/services. some have been making pipes with threaded center sections, to allow different lengths/frequincies for tuning. just add or subtract threaded 'spacers', instead of cutting the pipe. hope this helps, very nice looking work in the pics,btw.
Old 09-07-2007, 05:34 PM
  #8  
youdirtyfox
Senior Member
Thread Starter
 
youdirtyfox's Avatar
 
Join Date: Jul 2007
Location: , UNITED KINGDOM
Posts: 143
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Spinning a tuned pipe.

Hi Wil, yep old school spinning is still very much practiced at our shop. As you say starting of with circle cut blanks, then spinning up onto a drafting tool.
Then further down and down and till she's locked on

We spin to tooling mostly, have done some 'air' work though . I think the most impressive stuff we have worked is inconel jet engine cowls for Rolls-royce (namedropping,lol)
The chucks weigh in at a ton and half each !! bloody scary when that's spinning a 300rpm about a foot away from you ..

I think i would be able to spin sections to keep wall thickness consistent, have a found a tool that looks suitable, but a complete section tool could be made (cant afford it though)
Where you would be able to spin the pipe in one go, then remove sections of the tool , so spinning could be removed. or use a tapered center wood on the the tail stock?

Thanks for the interest people, soon as I get a quiet period at work i'll have a little play

Regards
Sam.



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


Thread Tools
Search this Thread

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

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.