WTB Cromodora CD32 Center Cap Backing Plates

[MurphinDC]

Yes, I know this may be a long shot, but I need four center cap backing plates for a set of Cromodora CD32 wheels I picked up.  I have searched in Europe and found the center caps but not the backing plates.  Found one guy in Italy, but he won't ship to the US....go figure.  Any good sources out there before I resort to making some myself using brass?  Image below. 

 

Thanks
Murph

[tangent]

Ever have any luck finding these or getting dimensions so you could fab them?

[MurphinDC]

Tangent, I did end up fabricating them out of brass.  I measured the inside of of the center hole using a caliper and my measurement was 1 3/4 in diameter.  You'll note in the photo I drilled a round hole in a block of wood using a center hole bit, going down about 1/4 inch and chiseled out the center.  Then I cut a round piece of brass with about 3/8 of an inch left on the outside.  I then punched a hole into the center of the brass and screwed it to the block of wood and started hammering away with a punch to flatten it out  Then I trimmed the outside some and that finished the plate.  I purchased screws that fit the hole and used a lock washer as well to secure them.  No issues with them staying on.

 

Hope that helps.

Murph

[tangent]

Thanks Murph!

 

Really appreciate your response and laying out your method for fabricating the CD32 center cap backing plates.  One more question, what thickness was the brass? 

 

Don

[MurphinDC]

I bought it on Amazon....it was Red Brass 22 Gauge Sheet - 6" x 6".  

• Red Brass - CDA #230 (85% Copper, 15% Zinc)
• 6 Inch by 6 Inch Sheet
• Thickness: 22 Gauge / 0.025" / 0.65 mm
• Unpolished

Good luck

Murph

[tangent]

Hey Murph,

 

Back again with another round of questions.  Wondering about outside dimension of center hole bit and how far out from center you started the slope.

 

Thanks, Don

 

 

[MurphinDC]

Not sure I'm understanding your question, but let me offer this.

• I used a 1 3/4" diameter center hole bit to cut the hole in my hard maple (old piece of butcher block)
• The depth of my cut with 3/8".  
• I used a piece of tape around the bit to get my depth uniform.
• I chiseled out the center using a wood chisel to match the 3/8" depth.  
• My floor of the hole wasn't completely flat across it's width as maple is a hard wood and tough to chisel, but it's pretty darn close.
• The slope you may see in the photo was not planned and was just from both my chiseling and pounding of the brass plate.
• The edge on the right of the picture got a slope in it from my pounding of the chisel.
• Make sure you use a hardwood and not a softwood, otherwise you'll lose our circle edge 

Did I answer you questions?  Tomorrow if I get a chance, I'll take off one of my wheels and see if I can show you the finished product.  It's not pretty but it works.

 

Murph

[tangent]

Now I get it!  I was looking at it backwards; not realizing you chiseled out the center!  Having made the center lower than the surrounding wood, you next screwed the center of the oversized (3/8"+1 3/4"+3/8") red brass plate to the maple, and then pounded the edges of the circular red brass plate to create an outer, sloped lip.  Sound about right?

 

So, a 1 3/4" wheel center hole and a 1 3/4" center hole bit.  Unlikely that all the pounding in the World would produce a  backing plate with a full 1 3/4" flat portion between the outer lips.  Does a small portion of the backing plate extend into the wheel center?

 

  

[MurphinDC]

Yes, sounds like you have got it!  Yes, you are correct in the second to last sentence. The 3/8" depth of the hole in the wood produces the depth needed for the plate to extend into the wheel.  I need to head out for a couple of hours, but as I said I will take a picture of what I produced.

[MurphinDC]

Here you go.  

[tangent]

Fantastic.  Really appreciate all the extra effort to get me on track.

[MurphinDC]

Glad to help!