Hey guys. I have read as much as I can on this in the search, so I decided to tackel this myself. I took a set of 15 by 8 chevy pickup rallys and cut the center out. Then I cut the center out of an old set of 15 inch stock steels chevy car wheels (I wanted the ones with the little humps between each lug nut hole). I measured the best i could before I took everything apart, (about 13 1/4 centers). After I got everything apart, I had my big 8" hoops with my cool old centers. But...... The car centers are 1/16th of an inch too small, I was hopping they would fit tight!!!! Sooo, what would be the best way to make this work? Sould I try to make a ficture to center the "center" to the hoop and fill in the little gap with weld? If I can center it it would only be 1/ 32 on all 4 sides. Any ideas????
there is an art to making widened wheels. i have been doing it for better than 25 yrs. the first thing is to not take the centers out of one and expect them to fit in another rim. if you want to more contact me and we will chat. www.bernieswelding.net
Tweak the flanges outward on your centers slightly with a large adjustable wrench. I build wheels all the time, and I run into this problem occasionally.
This should be too obvious but you need to true up the rim before you start welding. You don't have to make a jig, the front hub of the car will do. Make some kind of pointer so you can observe the runout as you turn the wheel. It should be within 1/16" both lateral and up and down. Also be careful to get the offset the same. Make a chalk mark on the floor to line up your pointer.
I worked in a wheel factory for 20 years. Those discs need to be press fit for max strength. Did you notice after you ground off the welds that the factory centers didn't fall out? You could bend the flanges with an adjustable then turn the centers in a lathe to true them up as suggested above, but make it a press fit. Mock it all up in your shop press for the back space required, using blocks and shims to attain the back space you need, but do not weld yet! Do both or all 4 of the press fitting using the same set up on the press for repeat-ability - you shouldn't 'eyeball this. Same goes for the radial and lateral runout. Use an old axle to make a jig with two dial indicators - one on the beadseat (radial) and one on the exterior "ear"/flange (lateral) Check both sides of the rim for true before welding. These checks can be done on the car too, but it's just not as easy. Hey, if it were easy, everybody would be doing it!
Ya, my plan was to use an old rear end I have and weld on brackets for my dial indacator. And yes the old centers were a tight fit to get them out. I was hoping for the same when i put them together, figured it would be alot easier to set the back space if they fit tight, just tap them. Maybe I will bend the center's edges slightly and try to get them trued up.
I think it is best to put the center back into the proper hoop, weld it and them cut the hoop apart and widen it. There was an excellant thread on how to do that by the rod builder in texas, don't recall his name but he does some great work and has a model 'a' pickup on his avatar.
I'm with OJ....although I haven't done it, I've seen it done this way. a jig was made with a spindle, hub and bearings. A torch was clamped in place to make the cut, perfectly. A hoop of the width to be widened was rolled at a local company that can do that sort of thing. The wheel was then assembled, trued and tigged back together. The center of the wheel wasn't messed with.
I would start over with one of your narrow wheels and leave the center in the wheel and have the rest of it machined off so all your left is the center and the band around it. Than machine the outside down so it's a press fit than cut the remaining band off thats not on the 4 mounting points off the center. One of the local guys that does wheels starts with 4 wheels to make 2. He cut's the rims off where it's flat in the middle of the wheel. He cuts the backside of the rim off with the center intact , than cuts the front side off the other wheel intact again, removes centers , welds rims together than reinstalls the center . If you just wanted to add to the backside of course the center wouldn't need removed. I tried a similar operation with old centers in some 4" spare shells. Trying to use sheetmetal shims and checking runout, it kept wanting to walk and couldn't get my runout set. I wouldn't rely on welding alone with an airgap between the shell and center. .045 max on runout.