fgd pump design

Centrifugal Pump and Engine

Centrifugal Pump and Engine

I know some here like the occasional challenge. No prizes but I thought the attached might make an interesting piece of work.

The description and drawings are from a 1920 publication: 'Machine Drawings for the use of Engineering Students in Science and Technical Schools and Colleges' by Thomas Jones and T Gilbert Jones.

The attached pages are just a small sample from Book 3. I'm not sure if there were more in the series but I have copies of Books1-4.

If wanted, I can scan and upload more

3D Print

Would make for an interesting print! The real challenge is modelling the pump housing. I made a stab at it but abandoned the first attempt. I will try again - maybe model the spaces and use boolean subtraction - not sure yet..

2D Drawing

My approach is to create a 2D drawing of each view mainly outlining the hard edges. Internals will be made in 3D CAD, the first step is roughing out the hard edges. After you have a clean 2D sketch position and align them where they will live. The 2D geometry is used as a guide for the 3D development.

Agree - a 2D sketch can be helpful - I might try that with the pump body.

Never had much luck with a 2d sketch derived from an imported image. Line thickness, intersections, and corners always give me pause when tracing, especially on parts that need to fit closely together.

I've always relied on a careful study of the drawing views and dimensions. Then created the individual parts feature-by-feature while reconfirming the "fit" according to the dimensions on the original drawing.

That said, I thought I'd give the impeller a try...

2D drawing (ACAD, Rhino) or parametric sketches are only used as guides for the 3D development it doesn't need to be perfect. With simpler parts eyeballing will work. For more complex assemblies especially if drawings span multiple sheets and details that approach helps me get started. Cylindrical and rectangular geometry is simple to make and everything can be adjusted later. Fillets, holes, cuts, bosses are added after the main bodies are developed. Dimensions are not important to match right away, they can get in the way. Parameters and constraints are the last step in my workflow. There are raster and PDF to CAD features and plugins that would save a lot of time.

Alibre's update to sketcher to allow geometry to scale together (autoscale sketch) really improves this style of sketch development.

Other Drawings

The other books are similar.

Book 1 is a little more basic but has details of some interesting machines. ~ 90 pages

Book 2 gets into more detail covering mostly industrial machines - ~ 90 pages

Book 3 - see for yourself..

Book 4 is aimed at DC electrical machines and is a much shorter volume ~ 30 pages

It seems to books were awarded to a young William Bowe Dobie for English and Drawing, session 1933-34 - form 1aT Workington County Technical & Secondary School

I bought the books from a nearby second hand bookstore a couple of years ago.

Having scanned book 3, I will scan and upload the others - but will have to wait a week or two!

I'll probably upload the full set to the Internet Archive once all are scanned.

We have a slightly younger version of this at work. Doesn't have pulley drive though, but is definitely WW2 vintage. It has been fitted with digital readouts and still does a decent job.

Excellent! I think these are earlier versions of the copies I have. I will complete the scanning of books 1,2,4 when I get back from holiday.

This is similar to the series of books by Timoteo-Carreras Soto. I've modeled most of the designs in his series of books. It is interesting that all these designs were drawn in 2D and their results are, as stated, pieces of art. Where the Soto drawings are piece-part drawing exercises the books you have appear to be complete machines in some cases. Very interesting.

Interesting to note some dates.. The 'original' Book 2 publication is dated 1898 and was priced at 2s(shillings). There is no date on my copy but it is second edition was priced at 5s. The preface notes the inclusion of 23 new plates. Adverts at the back of the book include one for Cardboard Working Models made of thick cardboard and printed in colours! Maybe some 3D prints are in order?

I do know that the original owner Willian Dobie wrote his name inside the front cover with the date 1934. If other searches I've done are correct, he would have been 18 at the time and went on to become Dr. William Bowe MSC PHD FRSA - clearly an accomplished chap.

Yeah - great deal better than I can do on my brother printer scanner thing!

Something is wrong with the pdf for Book3, it won't download and if it does it won't open.

I suspect it's an antivirus issue. I did test after uploading - no problems. I do intend to submit all the books to the Internet Archive in due course.