JowettTalk

I've uploaded a photo of the Jowett drawing of the Jupiter wheel.

It is in my folders under Jowett Drawings. I'm sure Keith will find a more suitable home for it.

Thanks John!

I will use the official dimensions to correct my drawing.

So what other Jowett drawings do you have?

Philip

So, I have posted my CAD drawing of the Jupiter Road Wheel in my Gallery here: https://jowettnet/forum/download/file.p ... &mode=view

I regret to say I have cracked over a dozen wheels, so here is my view.

There are two stress risers at each hubcap tang. This is where Dunlop stamped their logo, Made in England and the patent number, as well as mounting the tang. They pressed the rounded sheet metal flat, leaving sharp creases at the outside of those stampings. Looking at the inside of the wheel, this stamping can easily be seen as ridges across the surface.

The cracks begin at or in those sharp creases and radiate OUTWARD to the CLOSEST lightening hole. Each wheel has one tang which is equidistant from the two closest holes and the other two tangs have quite unequal distances to their closest holes. In my experience, I have never had a crack on the equal tang and it's always the closest hole that is at the end of the crack.

The cracks will also propagate inward towards the wheel center, running down the curvature of the stamping and heading towards the nearest wheel stud hole by running around the circumference of the flat area of the wheel center, then taking the shortest route to the hole.

The other thing that cracks is the flat area itself where the surface of the brake drum fits against the flat mounting area of the wheel. The radius of the drum surface is less than the mounting area of the wheel, allowing side loads of the wheel to flex the flat area of the wheel over the edge of the brake drum. These appear as small arcs which might be mistaken for normal wear pattern or witness marks.

I will try to post photos over the weekend.

Scott

Hello all.

During the restoration of JJ-1951 all those years ago, I discovered during preparation for painting that there were cracks in a couple of the wheels. The cracks were partially around the raised wheel stud pressings where the raised metal left the flat area (as shown in the image). There were also some radial cracks from the area just described (from memory!). Those wheels were repaired by gas welding and normalised in a furnace, but were evidently "scrapped", as I can no longer find them in what was the kids playhouse and which is now a storage facility! If I could locate them I'd photograph the actual repairs . . .

Back then, I was lucky enough to buy a set of 5 brand new Jowett Javelin wheels for the princely sum of $NZ25 (about 13 UK pounds in today's UK money ) Granted, I did need to make the ring of holes to make them into Jupiter wheels

So, I write this to show that my experience seems to be different to what others are reporting. My recollections are from my memory as I can't "prove" it with images (at this time), but my advice, for what it's worth, is for owners to have any good wheels normalised BEFORE they need repairs. My bet is that they were never treated this way when manufactured . . . . and most wheels have lasted pretty well. Normalised they might last forever!
After clicking on the "Overall image", so as to enlarge it, please feel free to download the resultant image to aid in your own descriptions and comments on this subject, (right click and "save image").

Keep well.
Leo.

Hello, Keith.

I wondered if a good place for this image to be copied to would be onto the Gallery in Philip Dingle's space (with his permission, of course). If put "alongside' his terrific CAD drawing of the Jupiter Wheel (and the wheel for the Javelin too, if the ring of holes were not included?) it could be of help to those studying the drawing to have a picture too . . .

What do you and Philip think about that idea? Would you be able to do this?
Just a thought.
Cheers.
Leo.

Good idea, Leo. That would work for me, unless Keith has a better idea.

Philip

Please post in Gallery and then I can move it.Or post in Legacy space and then Legacy moderators can move it I moved some of Philip's old CAds to there anyway.

Keith.
The upload to the Gallery has been done . . it's presently the Legacy bin.
Cheers.
Leo.

http://jowett.org/jowettnet/dt/tech/mod ... wheels.htm

Was some early work done on dimensions