War Department 16” divided rim: British and Canadian manufacture

[Mike Cecil]

Are these 'split-rims' or 'two-piece rims' or 'divided rims'? I know we all refer to CMP wheels as split rims, but strictly speaking, is that correct? I thought that split-rims referred to the rim with an outer locking ring which had a gap, and CMPs had two-piece rims? I noticed the diagram a couple of posts back used the term 'divided rim' - had not seen that before.

What's the correct terminology?

Also, Tony's comment about the 25-pdr and Trailer No.27 Mk.1 having left and right hand thread studs/wheel nuts. That is so for early production but by 1943, only right hand thread studs and nuts were used throughout, and retrofit kits issued for guns and trailers already in service. (Stud, Wheel, Cone seating, No.3 and Nut, Cone Seating, wheel stud, No.4). Just how many were retrofitted is an unknown, of course.

Mike

[Hanno Spoelstra]

Originally Posted by Mike Cecil

Are these 'split-rims' or 'two-piece rims' or 'divided rims'? I know we all refer to CMP wheels as split rims, but strictly speaking, is that correct? I thought that split-rims referred to the rim with an outer locking ring which had a gap, and CMPs had two-piece rims? I noticed the diagram a couple of posts back used the term 'divided rim' - had not seen that before.

What's the correct terminology?

The "divided rim" shown above come from the article on US wheels & tires.

The 1942 Ford MB-F1 Maintenance Manual lists "Wheel Type: Split"

[Richard Farrant]

Just to clarify the designation of these rims, known generally as a WD Divided Rim, here are some scans from LV6/MT14 Vocab showing specification details.
Note, FB/R means Flat Base Rim

[Phil Waterman]

Hi Mike and Hanno

You have raised a very interesting distinction that it would do us all well to remember. Particularly when we are looking for a tire shop to mount or dismount or mount our CMP tires. We should all be using the term Divided Rim with explanation they are two halves that bolt together in the middle.

In searching these two terms on line found a letter from OSHA (US Health and Safety) saying they were different. That Divided Rims were OK to work on with normal safety precautions.

Just something to stick in the back of our minds.

Cheers Phil

[Mike Cecil]

Interesting distinctions. The War Office 1966 driver training manual distinguishes the two types as 'divided type wheel' and 'three piece wide base rim' in the diagrams, then has an each way bet in the text: 'such wheels split into two or three parts to allow for replacement of tyre or tube'.

Looking more closely at the CMP manuals and parts lists, the Ford MBF1 uses the term split rim with the drawing of the wheel, but not in the text, and in both the Chev and Ford parts lists, the wheels are described as 'split' for the various sizes.

But neither the Chev MBC1 or C2 maintenance manuals use the term. All these manuals (MBF1 and MBC1&2) describe the wheel rims in the text as two piece.

Clear as mud, eh?

Mike

[Lynn Eades]

For those that don't recognise it, the diagram in Hanno's post#13 is of a WC Dodge rim (3/4 and 1 1/2 ton)

[David Herbert]

It seems strange that in Richard's post LV6/MT14 description that the PCD of the wheel stud holes is given in mm (and doesn't represent a sensible inch size) when everything those wheels fit were designed in inches.

David

[Hanno Spoelstra]

Excellent Richard, so Divided Rim it is!

Originally Posted by Richard Farrant

Just to clarify the designation of these rims, known generally as a WD Divided Rim, here are some scans from LV6/MT14 Vocab showing specification details.
Note, FB/R means Flat Base Rim