Disc brakes for 1917 model T speedster being built by Powerwagonmaniac1

For anyone interested here is the information about how I built them for my '17 T speedster:

Enjoy,
Chris Becker

The wheels you guys see in the photos are Houck #4 knock off racing wheels. I don’t have enough funds to purchase the original hubs so we went ahead and built our own. While I was at it I decided to adapt disc brakes to the front and rear. We needed to use the old wood wheel hubs to mount the Houck hubs to the spindle so an adapter plate was cut out and drilled to accept the rotor from a 1983 Nissan Pick up. This narrative covers the building of the hubs and adaptation of our setup.

I went ahead barrowed a single hub from a friend of mine up in Grass Valley, OR, to copy. I needed some help with the measurement and layout and a fellow by the name of Vic Nelson who was (recently passed away) a retired machinist helped with the measurements and in getting me started. Vic showed me how to set up the lathe and to cut the centering cones, external threads, and internal threads. After laying the measurements down on paper, I went down to Pacific Machinery and Tool Steel in Portland, OR, and purchased the right size steel round stock for the centering cones for the hub and caps. I want to say they are 4.25" in dia. but I would have to go measure the outside dia. of the cones.

We chucked the steel into our lathe, turned the cones into the base of the hub. Then we whittled the steel down to where we could machine the threads into the hub end. We machined external fine threads into the end of the hub for the cap.

The caps where done the same way except with internal thread. I needed an adapter plate to attach the hub itself and provide a place for the pins to be press fitted into. We burned a circular plate out of 1" steel plate. Then bored out the center hole so the Model T wood wheel hub would fit flush inside. We then welded the adapter plate and the hub base together to make one piece.
Finally I went to our large drill press and drilled the six holes in the adapter plate for the pins and turned the pins from some more roundstock, we had at the shop, and pressed them into the plate like the original. These steps were repeated four times to make a complete hub set.

I still have to make the locking mechanism in the cap. I’ll have to slot the cap about an 1/8 “, and then build an l-shaped piece that can be pressed down with a spanner wrench while unscrewing the cap to remove the wheel.

The disc brakes are off a 1983 Nissan Pickup. The rotors are mounted with six holes the same spacing as the model T wood wheel hubs. The only modification the rotor needed was to drill out the threads that were tapped into 6 mounting holes that mounted the rotor to the stock hub on the pickup. To get the rotors to turn true on the Model T wood wheel hub, we had to machine the inside face of the flange and the outside edges. The Model T hub fits into a recess on the backside of the rotor. This recess was raw casting so it had to be machined too. The Model T hub is press fit into this recess and bolted up to the rotor and the hub assembly we built.

I tried to use the matching calipers on the front, but when we put it on the rotor and installed the wheel there was a clearance issue. I ended up with calipers off a 1997 Mercury Mountaineer to gain almost ¾” between the wheel center and the casting of the caliper.

To mount the caliper to the spindles I made circular plates that cradle the cylinder with 2 threaded holes for the spring-loaded mounts. The mounting plate was then welded to spindle; you will have to pre-heat the spindle to about 400 to 500 degrees (I used a small toaster oven) to keep the heat affected zone form becoming brittle. When done welding bury the hot spindle and the plates you welded in dry sand. This will cool slowly and the parts will keep their integrity in the welded area.

I am still working out the rear disc calipers. I still have the same clearance issue as the front. I also want cable-actuated emergency brake so we ended up using 1992 Chevy Lumina rear calipers. I have large backing plates on the back axle that I can use as a mount; all I’ll need to do is cut a ½ circular notch to hold the caliper.

I just purchased the Master cylinder which came out of either a Ford Galaxy or Falcon, I don’t remember which but I do have the part numbers at the shop. There will be custom built mount that goes on the frame rail. I also need to modify the brake pedal by disconnecting it from tranny brake and then add a lever to the bottom of the pedal to push on the master cylinder.

All in all it took us just a little over 8 months to build my hubs from scratch. This was the first big project on our Martin lathe. I needed to learn how to use the lathe, so what better way then build the parts I needed for my speedster. I also spent many hours over at our local parts store driving the part counter guys nuts. When I decided to weld the hubs to the spindles I ended up talking to the head metallurgist at Stack Metallurgical (a heat treating company here in Portland, OR) and gave me the idea of pre-heating the parts and slowly cooling them. I have been working on this setup for over 2 years now and there will be many adjustments to make it work, but it will be worth it in the long run.

Resources:

Tim Knapp (NWVS member)

Don Shreve (NWVS member)

Nick Nichlos (RCMTC club member)

The book: Model T Speed Secrets: the Fast Ford Handbook (By Murray Fahnstock SAE1921) Lincoln Publishing, Lockport New York copyright 1996

Vic Nelson

Stack Metallurgical

Beaverton Auto Parts

Brian Walters and my dad Bill Becker

 

With only 58 views and no replies, I think a lot of us missed this post the first time around. Thanks for sharing this with us. I'm going to save this all as a word processing file for myself.

-Dave

 

thanks for bringing this back up. i missed it the first time.

 

Neato!!!!

One thing does sorta jump out at me though - most calipers I see place the caliper against a shoulder so that upon applying the brakes the mtg. bolts do not see any shear loads.

Not sure if you have enough tire to make this a concern or not, but I figured it couldn't hurt to mention.

Looks like a really fun and challenging project - this is true Hot Rodding!!!

 

Didn't Henry offer disc brakes as an option on the Model T?

HaHa just kidding.......incredible work!

 

Any drawings?

 

Looks good, thanks for sharing.

 

I'm bringing this back up to ask how they've worked out, if there are any changes, and so more people might see it.

Thanks,
Kurt

 

I would like to see more pics on this im building a t with a chevy 90 v6 and running a t axle and need frunt brakes. what about a drum break set up?

 

Very cool,keep it coming.....

 

I agree; I'd much rather see more traditional drums than disks.

 

If I remember correctly, Chris' chassis was torn down and used by him and Clayton to build the T "Becker Special" speedster for his dad, but the disk brakes were NOT used.

 

Nash Metropolitan drums were used by some guys. They are apparently a good match to the original "small drum" rear brakes.

-Dave

 

fantastic work, can u add a picture of the centre cap only if easy, I have houk wheels and drive hubs but no caps, what measurements did u use for your 24 drive pins if u don't mind me asking, just width and length did u get them made with cnc lathe, thank u and regards mark Australia.

 

It's been a while. You should probably send a PM.

 

sorry I am new at this, I have houk wheels and the 6 pin drive hubs ( the 24'pins all need replacing) I am missing the locking centre caps. I found the above disc brake work very impressive, thank you mark Canberra Australia. And mr. maniac do u remember the o.d. Width you machined the pins to? and did u just press them in, I was thinking I might also bolt mine from the inside rather than pein them over. Just to make them serviceable.

 

Please show how the 'backing plates' attach to the spindles, (it says welded)
Theres a guy in Texas using old VW drum brakes

 

Since this old thread has been brought up, and no one else has commented on the caliper mounting, I'll have to agree with Hemi. The caliper has to be mounted to it's factory-designed bracket, which locates and positions the caliper and pads. (Those "ears" on the pads are not there for looks; the pads are what do the braking) This bracket is then mounted to the spindle, directly or through another bracket. The caliper mount bolts are not designed to, or should handle any brake torque. They only secure the caliper to it's bracket.
Although nice work has been done, some is just plain wrong. Sorry to rain on your parade.