Register now to get rid of these ads!

Technical Banjo Building Blues . . . Sing Along Boys, Sing Purdy . . .

Discussion in 'Traditional Hot Rods' started by Bored&Stroked, Jul 17, 2019.

  1. Well, trying to get the 32 FlatCab ready for the Colorado Hill Climb in September. I ruined the stock rear end (early 32 - like a Model A) last year on Ida's dyno. I expected it to not take the abuse and it proved me right. Oh well . . . was still fun.

    Anyway - have acquired two late 32 - 34 complete rear ends, with my initial plan to tear them apart, take all the best pieces and build one good late style 32 rear.

    Early Versus Late 32 Rears: The early (and most common) 32 rear is really a Model A left over . . . you can identify it by it having a round torque tube mount on the center banjo carrier. It is also the weakest of the rears used in 32 - as it has no pinion support, has the goofy tapered driveshaft-to-pinion mount, etc.. The late 32 rear is pretty much the same as the 33 - 34 rears - other than the radius rod mounts are straight (on the housing) - versus angled like they are in 33-34. You can easily identify it by the "scalloped" flange on the torque tube mounting flange - just like 33-34 and later.

    Plan A - Build a Late 32-34 Rear - Stock Setup: The idea was to NOT really increase the strength of the rear (still use tapered axles), just get a good set of parts in to one rear end, put some "axle breakage retainers" on the drums and go to Colorado. How hard could it be???

    Well, you know how it goes . . . all well made plans go to crap about the time you start into them.

    Using an Engine Stand: I did one smart thing before I started, I made an adapter plate to mount a banjo (or later quick change rear) to one of my engine stands. This REALLY helps the whole disassembly, rework and assembly process. I've done more dang rear-end work on jack stands - just one big pain in the ass - time to fix that issue.

    Here the plate is - mounted to a Jones Big QC style center section (note: same bolt pattern as the Early Ford carrier - been that way for years):

    IMG_7500.jpg


    So I proceeded to take both rears apart . . . guess what . . . not enough damn good parts to build ONE good rear end . . .

    IMG_7503.jpg
    a) Two worn out axles - differential drive gears are really worn.
    b) One axle with stripped threads . . .
    c) Exploded pinion support bearing . . . pieces in the bottom of the housing
    d) One broken/chipped ring gear and worn out pinion (due to the above bearing failure)
    e) Worn out spiders and cross shafts
    f) One housing with worn out outer hub bearing surfaces.

    IMG_7519.jpg

    One big pile of rear end crap on my floor . . . and along with all my "spare parts" in various cabinets, not enough to solve the problem.

    So - this is chapter one of the saga . . . stay tuned as I get into my 'Plan B' . . . I will be building at least TWO different rear ends. Will get into the key differences in 32-34 versus later carriers, ring gears, housing bell clocking, bearings, etc..

    1) Based on a modern "Banjo" variant - with 32 housing ends, modern locking differential, Hotrod Works bearing adapters, 8" 28 spline axles, Bass Custom brakes, special torque tube and driveshaft setup and other such fun . . .

    2) A stock style 32 (after I find all the damn parts I need!). With a repop 3.54 gear set, new internals, stock axles, etc..

    More fun to come . . .

    B&S
     
    Jet96, brad2v, greener200 and 4 others like this.
  2. I already know this will be a future sticky for me, to revisit. You post tech' ... and therefore always mean business. Bookmarked, to level up !!
     
    bct likes this.
  3. 47streetrodder
    Joined: Oct 27, 2007
    Posts: 104

    47streetrodder
    Member

    Looking forward to following this. Always interested in the "mysteries" of the Ford Banjo.
     
  4. shivasdad
    Joined: May 27, 2007
    Posts: 584

    shivasdad
    ALLIANCE MEMBER
    from Texas

    I'm in. I can only play the radio though, no one wants to hear me sing.
     

  5. Here is the pile o' crap I ended up with . . . we will soon make something valuable out of it and a few additions.

    IMG_7520.jpg
     
  6. TBone69
    Joined: Aug 21, 2007
    Posts: 833

    TBone69
    Member
    from NJ

    I feel you pain, took 3 model A Banjo's to put a good one together. Looking forward to this thread to learn some new tips. Love the banjo engine stand mount. If and when I rebuild another one I'll be making one up
     
  7. dumprat
    Joined: Dec 27, 2006
    Posts: 3,479

    dumprat
    Member
    from b.c.

    Having built a one piece axle swap from scratch for my old T modified and fixed one someone else built with 8" parts I am sure if I do it again I am going to throw the side gears in the bush and use a lock rite or similar locker.

    The differential action isn't very smooth anyway and spinning both tires would be nice.
     
  8. dumprat
    Joined: Dec 27, 2006
    Posts: 3,479

    dumprat
    Member
    from b.c.

    And a lock rite is a rebrand of a Chrysler "All trac" which has been around since the 1940's so it's pretty damned traditional
     
  9. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,681

    Bruce Lancaster
    Member Emeritus

    I suspect you know this stuff inside and out, but for the next generation...tour the banjo section of a '28-48 catalog. The actual differential case (the one inside, not the actual banjo!) is the same up through '48, so case and gears there can be located. Use of the later axles (note---there are two tooth counts for axles and side gears, but both sets of parts are common) would be possible if '35-40 type axles are right length. R&P are close relatives, early type is just a slightly trimmed late. This would seem to allow use of late pinion with a later driveshaft shortened to suit, if there's any help in that.
    It's unfortunate that all the side bolt holes are on different rotations so you can't just swap in a complete late banjo center redrilled, because (see picture above!) as only the bolt hole locations are thick enough to accept a bolt hole!
    Another general banjo point...distance from centerline of banjo to torque tube flange differs, killing the idea someone gets every few minutes of bolting an early '32 tube and driveshaft onto a later style rear.
     
    Moriarity, Jet96, brad2v and 2 others like this.
  10. hotcoupe
    Joined: Oct 3, 2007
    Posts: 588

    hotcoupe
    Member

    IMG_20190719_122712.jpg IMG_20190719_122712.jpg IMG_20190719_122737.jpg Dale, you asked for suggestions on improving the late '32 rear axle, here's my take on it. I added a ring gear support (bevel gear set tends to force the ring gear away from the pinion gear),simple steel housing with a threaded brass stud that rides in close proximity (.0005 - .001 ?) to the outer perifery of a ground surface of the ring gear. Groove is for "See images
     

    Attached Files:

  11. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,681

    Bruce Lancaster
    Member Emeritus

    Ford itself put those brass supports on the truck rears, I think without research starting when the full floating axles were introduced, and I think other trucks use them as well, so you could work around an available part with bearing type brass ready to use.
    Another line of thought...torsion-bar sort of axle or driveshaft. I have heard of such tech, as on a '55-7 Chevy smallblock racer. The car involved kept breaking oil pump driveshafts allegedly because of too rapid acceleration of engine speed.
    A real red-blooded American would simply have made up a 2 inch thick drive out of surplus parts from a tank recovery vehicle, but this guy was more subtle, perhaps a Ninja or something.
    He turned down a driveshaft a bit and defeated the problem, as the new part could twist more to eat up surplus violence. Hard to really say what actually happened before and after the mod without high zoot laboratory observation, but any way he did something and the problem went away.
     
    brad2v and Jet96 like this.
  12. That should work! This concept has been used by just about all of the full-size Quick Change manufacturers. Almost all of the side-bells have an adjustable "ring gear rub block" - or a cast bung right into the side-bell itself. Obviously these quick changes are being used a lot for various dirt track and other race cars where the typical engine HP is pushing past 800 HP these days - they have to take some abuse!
     
  13. dumprat
    Joined: Dec 27, 2006
    Posts: 3,479

    dumprat
    Member
    from b.c.

    Load bolts are pretty easy to make.
    A threaded boss welded to axle housing.
    An aluminum bronze rubbing block
    And a fine bread bolt with jam nut.
     

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.