Pics, ideas of convertin 38" wheels for a WC

Was wondering if anyone has any pictures they would like to share of their rims that they converted to work on the 6 bolt rear WC hub.   I bought a set of wheels/tires that didn't come with any centers.   I am debating of doing a couple things with them.   I could just make a flat round plate and weld it to the rim and have the bolt pattern made in the middle to fit the WC pattern.  If I did that which I think many other people have done, what thickness should I make my center out of?  Is 1/4" plate sufficient?   My other idea that I thought of driving home with them today is making four mounting points and putting a set of WD/WD45 eight bolt wheel centers in the middle and the mounts would pick up the four locations of the eccentrics.    Then if I wanted to switch them for the WC, I was going to take another set of WD centers and cut out the center section and replace it with a new center that had the WC bolt pattern on it.   That way these tires could be used both ways.   My only concern is if making a bracket in four different locations that would pick up the eccentric locations would be strong enough when they are offset further out for a 38" rim.   Any ideas are welcome.   Really getting geared up to go to 38" rubber to have a better footprint like most of the competition. 

To put 42" rims on my 4020, I found rims with tabs inside. 8 tabs. The wheel centers made for wedge mounted rims have 12 holes equally spaced. I made four plates per wheel out of half inch plate with the outside beveled to fit in the rim and to span two tabs, then each plate spanned three bolts on the original wheel center. So far it has worked fine and the narrow rims run truer than the originals did with the wedge mounts.


This is the best picture of them that I have. The key was that the outer face of the wheel center was machined flat at the bolt holes, so the plates fit well.

Other step up rims had a deep drop in the middle for the wedges or a circular flange welded inside the rim to do what my 4 plates do, but those were mostly for going to 38" rims on 34" rim centers, and going to 42 was a pricey custom rim. And I was able to do most of the machining of the plates.

The conical shapes of factor wheel centers give better lateral stability and a great range of tire spacings by allowing the tires to be closer than the ends of the axles and the drop boxes. Or wider by reversing the rims. A flat wheel center would bend sideways easier.

Gerald J.

I'd advise against the 38" flat discs only with only 1/4" thickness. There's a reason why most wheel centers aren't flat......they would bend too easily if flat, so to keep them from bending they need to be very thick, which adds weight and expense of material. At a minimum you'd need to add some gussets from the rim inwards to strengthen and keep the 1/4" flat discs from bending.

I was told that the factory press steel centers 24" in about 38 or 39 could be cut out and welded to a 38" press steel rim.

Larry, that would be great.   Thanks.  

Here are a couple sets I've built using the standard WC cast center, I cut the centers to reduce weight and welded spider adaptors in the lower set and bolted spiders with loop rims in the upper set, these are 36" wheels, but I have built 38's the same way. Upper rim weighs about the same as a pressed steel 38" wheel.

 Ah, the infamous "doily" wheels.  Remember when Gramma would crochet doilies for the tables and chair backs?  I think Ken crochets those from steel wool. Ha Ha Ha

  you can also buy 36" wheel fom a f-20 or 30 and it will bolt to the hub  they done ok too  when we were pulling

Larry, is that a dished rim center in a 9 bolt 38" center?   I think I found a set of 38" centers I can use as well, and that idea may work for getting me rolling.   Thanks for posting. 

A word of caution:  Do not weld rims with  the tires on them!!  Welding centers may or may not be OK, but welding rims with the tire one, even with the bead broken can kill you!  Google it and watch the videos.  The tires can explode quickly from a chemical reaction triggered by the heat.   You may already know this, but it bears repeating just in case.


Edited by Rawleigh - 23 Mar 2011 at 10:59am

Chuck,  Here is another approach that was used on a WD.