War Department 16” divided rim: British and Canadian manufacture

[Hanno Spoelstra]

Canadian made rims have the valve stem opening to the left of the bolt. Two of the eight bolts are longer than the other six.

This example has no maker or date stamp, only "6.00 / 16".

IMG_E5925_resized.jpg IMG_E5926_resized.jpg IMG_E5927_resized.jpg IMG_5936_resized.jpg IMG_E5928_resized.jpg

[Hanno Spoelstra]

As per the thread new 9.00-16 tyres for WD split rim wheels, Mike Kelly measured up some tyres and found out that the wheel diameter of the British/Canadian 16" tyres and rims are ¼" larger than those of US 16" tires and rims. That is why standard 9.00-16 tyres which are not marked "for British rim" can be hard to fit to this type of rim.

I measured the circumference at the bead at 129 cm which converts to a wheel diameter of 16,2 inch. The circumference of the British and Canadian made rims is the same.

Wheel rim dimensions.gif

[Owen Evans]

My Canadian rims have the attached instruction plate welded to them. Not present on my British rims (but they could have corroded away, of course).

Owen.

[Hanno Spoelstra]

Originally Posted by Owen Evans

My Canadian rims have the attached instruction plate welded to them. Not present on my British rims (but they could have corroded away, of course).

Thanks for the addition, Owen. I have a British rim for sale which still has the instruction plate attached.

IMG_5931_resized.jpg

[Jacques Reed]

Hi Hanno,

Another difference I have noticed between Ford Kelsey and GM Canada rims is the GM rims have an embossed pattern around the outer rim just noticeable in the photo. Ford rims are smooth at that position.

Cheers,

[Hanno Spoelstra]

Originally Posted by Jacques Reed

Another difference I have noticed between Ford Kelsey and GM Canada rims is the GM rims have an embossed pattern around the outer rim just noticeable in the photo. Ford rims are smooth at that position.

Thanks Jacques, I have never noticed that before (or did not recall Tony mentioning this back in 2006...). Nice detail!

[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 Owen Evans

My Canadian rims have the attached instruction plate welded to them. Not present on my British rims (but they could have corroded away, of course).

Here's another variation of the instruction plate, have not seen this before.

This is a British rim, as it has the valve stem opening to the right of the bolt.

British 16 inch rim instruction plate.jpg

[Tony Smith]

Originally Posted by Hanno Spoelstra

This example has .....

Attachment 114791

..... Angle grinder cuts where the wheel nuts were cut off!

Not meaning to divert this thread, those cuts can be repaired to present a better finished rim before final painting.

While naturally a bead of weld will fill the grooves, the weld itself will require further grinding to clean it up flush and present a smooth lug nut seat. Some people might also have qualms about heat damage from the weld affecting the temper of the rim, and therefore it's structural soundness.

I have had great success with a metal filling epoxy called JB Weld. It can be shaped, sanded, or ground easily and binds securely to metal, so won't fall off in a slab years later. Readily painted with any automotive primer and paint system (ie Enamel or Acrylic). It doesn't just work on repairing grind marks, it also does a fantastic job on sandblasted rims that have hollows from rust pitting or gouges from kerb strikes. You'll have that rim looking like new again.

[Mike K]

Found this , haven't read it yet.

http://www.usarmymodels.com/ARTICLES/Tires/tires.html

[Hanno Spoelstra]

Originally Posted by Mike Kelly

Found this , haven't read it yet.

http://www.usarmymodels.com/ARTICLES/Tires/tires.html

Lynn posted this link also, upon actually reading Kurt Laughlin's article I found an interesting drawing.

The US 16" rim was 15.965" in diameter and had 5 deg. bead angle.

US Combat Rim.jpg

[Hanno Spoelstra]

Originally Posted by Hanno Spoelstra

Lynn posted this link also, upon actually reading Kurt Laughlin's article I found an interesting drawing.

The US 16" rim was 15.965" in diameter and had 5 deg. bead angle.

Worth a read if you want to turn down your rims to fit new tyres currently available.

The 16” divided rim has plenty of thickness to allow machining 0.125” off:

9E8C1018-D13A-428F-9C3F-4ABF2BA7A16D.jpeg

[David Herbert]

In the article Jim describes his modification as not attempting to machine the 5 degree taper used on the Dodge rim but instead to machine the new seating area parallel and about the same diameter as the mid point of the bead contact area of the Dodge rim. I would have thought that any lathe capable of this machining could have just as easily reproduced the 5 degree taper and exact start and outside diameters of the American standard. This would provide a better seat for the bead and make dismounting easier if needed. It really is not hard to change the angle of the compound slide and turn the handwheel manually on any lathe !

David

[Grant Bowker]

One thing that would concern me about turning a taper would be to minimize the loss to the rim near the join line. In other words: if turning a taper, just put it in the area nearest the flange, then turn a parallel section further inward to maintain thickness/strength.

[Hanno Spoelstra]

Thanks for the tip, will use it when I need to restore the rim.

Originally Posted by Tony Smith

..... Angle grinder cuts where the wheel nuts were cut off!

Not meaning to divert this thread, those cuts can be repaired to present a better finished rim before final painting.

While naturally a bead of weld will fill the grooves, the weld itself will require further grinding to clean it up flush and present a smooth lug nut seat. Some people might also have qualms about heat damage from the weld affecting the temper of the rim, and therefore it's structural soundness.

I have had great success with a metal filling epoxy called JB Weld. It can be shaped, sanded, or ground easily and binds securely to metal, so won't fall off in a slab years later. Readily painted with any automotive primer and paint system (ie Enamel or Acrylic). It doesn't just work on repairing grind marks, it also does a fantastic job on sandblasted rims that have hollows from rust pitting or gouges from kerb strikes. You'll have that rim looking like new again.

[lynx42]

Originally Posted by Tony Smith

..... Angle grinder cuts where the wheel nuts were cut off!

I have had great success with a metal filling epoxy called JB Weld. It can be shaped, sanded, or ground easily and binds securely to metal, so won't fall off in a slab years later. Readily painted with any automotive primer and paint system (ie Enamel or Acrylic). It doesn't just work on repairing grind marks, it also does a fantastic job on sandblasted rims that have hollows from rust pitting or gouges from kerb strikes. You'll have that rim looking like new again.

I purchased J B Weld yesterday. A$18.20 from Autobarn Bairnsdale. The only place in town who had some.

Cheers Rick.

[Hanno Spoelstra]

Originally Posted by Hanno Spoelstra

Canadian made rims have the valve stem opening to the left of the bolt. Two of the eight bolts are longer than the other six.

This example has no maker or date stamp, only "6.00 / 16".

Triggered by Jacques’ photo and on closer scrutiny of this Canadian made rim, it does have a vaguely visible maker's stamp "General Motors Canada 1941".

3EB68C6C-2D54-45EE-889F-20862B43BC5B.jpeg