Do any members of the group have details/dimensions for a double petticoat pipe? I have seen photos of one and the claim is that they provide better draughting along with a more realistic exhaust beat from the chimney. I'm currently building a 5" gauge Britannia and would like to try a double petticoat pipe out. Cheers Jim
there was a couple of articles in ME vol 163 by Harold Barton in which he gives some ideas on improving draughting. He gives various simple formulas for designing the complete system based based on the results of his own experiments. He goes on to give details of a double chimney system for a 3½" Patriot but it should be possible to design a similar system for any loco using the formula he gives. If you think the articles may be of use I can scan them and email them to you (assuming you don't have them yourself). I think the main advantage of the double chimney is that you can increase the total area of the blast nozzles and so reduce back pressure in the cylinders. A similar effect can be obtained by using multiple nozzles into a single chimney.
Baggo could you e-mail them to me as I am trying to improve the steaming of my RUSSELL, I was using the information in EIM from the other month, but it seams to be lacking a bit, and so mostly trial and error would have to be used...
****** at ********-***** dot org dot uk Obviously replace the dot and the at with . and @ (The deed has been done)
Thank you John for that information regarding the petticoat pipes. I don't have the article you mention but I can access it here locally. I much appreciate your offer to get me a copy. Thank you John. An article in the latest edition of Australian Model Engineering features photos of a double petticoat pipe but sadly the author didn't include the technical details to design one, hence my query. I'll keep you posted on my success or other wise with this project. Thanks again, Jim
There is an article with details in AME issue 132 for May/June/2007 on page 57 . It is a copy wright . If you can't find the magazine let me know I will email the page .
Thanks for the kind offer Shawki but I have that issue of AME. Unfortunately the author while full of praise for the effectiveness of the double petticoat pipe, didn't supply any dimensions or details for designing your own. Jim
Have you had any luck with obtaining the article ?
Was quite interested when I read this article in the AME, our club have a full cataloged set of the ME mag from those early years.. You will need edition October 1970 Pg 972 & 973
it has reference to a loco that had to run with the blower on continuous to build pressure, since trying the double petti coat idea, the same loco, keeps the blower shut and the smoke box door open at times to stop the constant blowing off