[FONT=Arial, sans-serif]When looking for safety hubs for my Model T Ford dirt track racer I was generally disappointed in the manner in which various manufacturers used to hold the large bearing to the machined spooled. I recalled a method of threading the end of the later style ford rear axle housings and using a threaded nut to keep bearing in place and adapted it to this style safety hub.[/FONT] [FONT=Arial, sans-serif]Figure 1, shows a common rear safety hub with the exception that the end if threaded. One of the two grooves is for an O ring and the other a retainer bolt and nut. The safety hub has a hole of sufficient diameter to clear the axle by 1/8. The outer diameter of the hub has very close tolerance to the inside diameter of the steel tubing to eliminate transfer of bending strains to the axle.[/FONT] [FONT=Arial, sans-serif]Figure 2, shows the hub from the rear. I used a double oil/grease seal.[/FONT] [FONT=Arial, sans-serif]Figure 3, is the assembly from the front. The nut and lock washer are often called Whittet-Higgins, but are simply precision locknuts and washers.[/FONT] [FONT=Arial, sans-serif]Figure 4, is the stock Model T Ford wire wheel hub re-drilled for the 5 by 5 ½ bolt pattern and 5/8 diameter studs.[/FONT] [FONT=Arial, sans-serif]Figure 5 is the modification to the Model T rear axle housing. Cut off the stub end of the housing at the junction of the cast hub and tube (approx. 1). If your axle is completely assembled a trick is to slide a piece of PVC pipe over the axle shaft to protect it.[/FONT] [FONT=Arial, sans-serif]After hacksawing grind or file the end of the housing to smooth.[/FONT] [FONT=Arial, sans-serif]Chamfer the inside of the axle tube to allow the O ring to compress during installation.[/FONT] [FONT=Arial, sans-serif]Figure 6 is the hub loosely installed in the axle tube.[/FONT] [FONT=Arial, sans-serif]Figure 7 shows the entire assembly installed.[/FONT] [FONT=Arial, sans-serif]Figure 8 shows the aluminum spacer needed for the Model A Brake drums.[/FONT] [FONT=Arial, sans-serif]Figure 9 shows the Model A drums installed. The drums have reinforcing bands installed.[/FONT] [FONT=Arial, sans-serif]Figure 10, complete![/FONT] [FONT=Arial, sans-serif]Figures 11 shows how the safety hub is retained in the housing. One is installed in place of the original grease cup an additional hole is drilled and tapped approx. 150 degrees from the original. The dog point of the set screw must fit in the groove of the hub, but not jammed against the hub. This allows for a small amount of end play. Tighten lock nut securely.[/FONT]
WHy would you have to redrill the wire wheel hubs when the bolt pattern for the 26-27 wire wheels IS 5 on 5.5" circle?
Where the stud goes through the axle housing (figure 11) and comes in contact with the new carrier. Usually machine a flat spot perpendicular to the grove that is cut in the carrier. This keeps the new carrier from potentially rotating in the axle housing.
as a possible research project, should look into adapting a more modern set of brake shoes and drums into a 26/27 rear end. On my last speedster I set up the rear internal brakes as a cutting brake, worked really good.
On an earlier version I did not use a groove. I transfered the location of the grease fitting on the axle housing to the new bearing carrier with a center punch, pulled the carrier out and then drilled a pilot hole in the carrier for the dog point set screw. This would prevent the carrier from spinning and in retrospect sounds like a better idea. Thanks
Ah, I missed that you had drilled a centering hole, saves alot of time. That is a slick set up using the stock grease hole...since I think it is no longer usable. Now just make a grease cup that threads over the top and no one is the wiser.
You're right on the Model T part hole pattern. I'm running later style wheels on the racer, figure 10