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Rear radius rod question

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  • Rear radius rod question

    I have discovered something I haven't seen before. I was going through the 3 or 4 pairs of rear radius rods to pick the ones to use on my phaeton's rearend and noticed something I haven't noticed before. The brackets for the brake rod springs are different for some of them. The most common ones are the ones in the third picture - maybe 29 radius rods?? The brackets that are sandblasted are from a 28 set I believe, but I can't be sure. I bought them with a 28 rearend. Have you guys seen the 3 kind of brackets welded to the radius rods and know what is what? I see nothing in the JS's other than the early style rods, the later 28 and 29 style rods and 30/31 rods.
    Rusty Nelson
    Last edited by wrndln; 11-10-2018, 08:09 AM.

  • #2
    Rusty, I think that the distinction on those radius rods was the rear end shape and size. I'm not sure there is any other way to distinguish them properly. How about pictures of the axle housing mounts to go with the tab pictures.

    You also mentioned about getting a '28 rear end, is that rear end the one with the 3:70 gears? The reason I ask is because after about June '28 all the rest were pretty much the same except some small casting changes.
    You wana look waaay far up da road and plan yer route because the brakes are far more of a suggestion than a command!


    • #3
      All general statements are false. Which is a general statement.

      Generally the sequence of parts is: forged, stamped, reinforced stamping.

      Without a trip to the Benson???


      • #4
        As I see it,...without seeing the back side, this correct Jim?
        Photo #3 is (1)..
        Photo #1 is (2)..
        Photo #2 is (3)


        • Jim Mason
          Jim Mason commented
          Editing a comment
          That would be my guess. But without the drawings from Benson it is just a guess.

      • #5
        This is part of the Rear Radius Rod Assembly (A-4750). If you were to look up the part number on the MAFFI site, it would list about 44 different changes that were made to the assembly itself over the Model A years. The part in question MAY be refered to as the Brake Rod Spring Bracket---Rear but not sure. It would have a specific part number attached to it but I did a search and could not find it.

        If you knew the part number, more than likely you could find out the change in design. I found all parts related to the assembly but this one!

        You have A-4750-A with 7 changes; A-4750-B with 11 changes; and A-4750-B2 with 7 changes. However not all "changes" are "construction" related. These assembly changes would relate to specific parts on each style whenever there was a change of some sort. Jim the Benson.

        Interesting Rusty...Thanks for the "heads-up"! What kind of "ends" are related to each of the three photos above????

        Last edited by Steve Plucker; 11-10-2018, 08:30 AM.


        • #6
          I don't believe any of the brackets were forged after looking at them closely. They all look like they were stamped from heavy gauge metal. I can't see Ford forging or buying a bracket so simple, as they were very cost conscious and forgings were more costly than stampings. Maybe there were multiple suppliers for 28 and 29 and they took poetic license in make the anti-rattler brackets. Like I mentioned in the initial post, these radius rods are not 30/31 parts.
          Rusty Nelson


          • #7
            There were 2 'ends' in 28.


            • #8
              Originally posted by wrndln View Post
              I don't believe any of the brackets were forged after looking at them closely. They all look like they were stamped from heavy gauge metal. I can't see Ford forging or buying a bracket so simple, as they were very cost conscious and forgings were more costly than stampings. Maybe there were multiple suppliers for 28 and 29 and they took poetic license in make the anti-rattler brackets. Like I mentioned in the initial post, these radius rods are not 30/31 parts.
              Rusty Nelson

              There were a few "small" brackets that were forged.

              No real sence in the Benson!



              • #9
                Jim Mason and Steve Plucker,
                All the brackets in the pictures I posted have the brackets welded to the radius rods June 28 through May 30 in the picture from the JS's you posted. I didn't notice the later 28 and 29 radius rods were used until May 1930.
                Rusty Nelson.
                Last edited by wrndln; 11-10-2018, 11:42 AM.


                • #10
                  FWIW, both of my early '29's have the brackets in your second picture.


                  • #11
                    Here are the brackets on the unknown month, first style radius rods. also found on my May 28.

                    Here is a dec27 to mid 28 (based on brake rod return springs) picture from this site. same as above.

                    Here's is the brackets found on my 29 rear end 2nd style, and on my 3rd style unknown date rods.

                    Last edited by Jim Mason; 11-10-2018, 12:29 PM.


                    • #12
                      So far the sequence is

                      no return spring bracket

                      That leaves this one.


                      Anybody have it, with month & Year known?

                      Benson is still the best answer.


                      • #13
                        Unfortunately all of the four model A's I have were pretty abused and messed with over the years, so I can't really be sure the rear ends and radius rods that came originally on the cars are ones originally installed at the factory. Gary Karr's post about his early 29's that have the second style in the pictures I originally posted is a good marker, as I believe the radius rods were the same as when his cars were manufactured, unlike my vehicles. I only have one radius rod that has the bracket like Gary's cars (second picture) and unfortunately I can't remember where I got it or which vehicle it came on. Until recently, like a week or two ago, I never noticed the different styles of brackets.

                        I have never seen the forged brackets (early 28) like Jim Mason posted on a couple post back. They are quite different from the ones I have. I will check on cars I see in the future for which brackets they have and the date the vehicle was manufactured.
                        Rusty Nelson


                        • #14
                          I got under Dave Lopes' June '28 Phaeton this afternoon and the brackets on it's radius rods are the forged type, displayed in Rusty's third picture.
                          Last edited by Gary Karr; 11-11-2018, 12:50 AM.


                          • #15
                            Anyone know what the specific part number is for this peice?

                            FOUND IT...It is A-2505 Brake Rod Spring Bracket-Rear. There were about 11 changes to this part BUT that does not mean there were 11 different types. One will have to review the Part Releases to see what each EI has to say about them. A-2505 has 3 and A-2505-B has 8 which would be associated with the three types of Rear Radius Rods.


                            As it is...It looks like we have at least 4 types??????

                            Last edited by Steve Plucker; 11-11-2018, 05:59 AM.


                            • #16
                              Well I'm 10 hours from the Benson, so here's my guess at the sequence.

                              no bracket

                              1st bracket. (this could be slid down existing radius rods and spot welded) based on my unknown month and may 28 1st style radius rods.

                              2nd (lighter forging, this would be attached at production of the radius rod. Used end of 1st style radius rod and also used on the beginning of the second style radius rod) based on Davie lopes June style radius rods and Rusty's June to May 30 radius rods.


                              3rd (heavy reinforced stamping. used on the 2nd style ) based on Rusty's unknown 2nd style radius rods.


                              4th (dropped reinforcement. used end of second style radius rod, to EOP) based on Rusty's 2nd style and my 3rd style)


                              Just a wild ass guess on the data we have. n=11 is not a large enough population to be more than a guess.


                              Whose near the Benson with time to go?
                              Last edited by Jim Mason; 11-11-2018, 09:42 AM.


                              • #17
                                Thanks to all that posted to this string. Some interesting information was discussed.
                                Rusty Nelson


                                • #18
                                  FWIW Jan 28 Open Pickup ... appears to be 1st style


                                  • #19
                                    Speaking of Benson ...
                                    Im not able to visit but would be interested if there is anyone in the its vicinity that routinely visits? Have a few early 28 items I’d appreciate him/her digging into a bit deeper than current JS/RG information.


                                    • #20
                                      Won’t Benson help you over the phone, instead of going?
                                      3 ~ Tudor's
                                      Henry Ford said
                                      "It's all nuts and bolts"

                                      Mitch's Auto Service ctr


                                      • #21


                                        • Mitch
                                          Mitch commented
                                          Editing a comment
                                          I met Lee Watson at Branson who works or volunteers in there doing just that. Everyone was mentioning about having to go there which is not necessary

                                        • Jim Mason
                                          Jim Mason commented
                                          Editing a comment
                                          I'm cheap...grin

                                        • Mitch
                                          Mitch commented
                                          Editing a comment
                                          Naaah Model A'ers aren't cheap

                                      • #22
                                        Found this in area 4


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