Welded Wheel Studs onto Hub

[Chris Van]

Hi Boffins
Please see the attached pic. I please want confirmation that what I have done is okay. I have just fitted four new cast iron brake drums. We pressed out the old studs and the hubs got a bit distorted so we had them warmed up and straightened and then turned on a lathe so they were perfect and fitted 100% flush into the new cast iron hubs (which cast iron drums we had skimmed because they were not perfectly round). Then the fitter and turner advised me that if we swaged in the new studs we ran the risk of cracking the cast iron drums (which were expensive to import to South Africa). So, instead of swaging them, we cleaned up the countersunk holes on the hubs, and then put the new studs in and pulled them tight onto the cast iron drums with a brand new set of ordinary nuts and washers. Then we had the studs expertly argon welded to stop them falling out when you put the wheel on, or turning when you tightened the wheel nuts. This means that the wheel nuts effectively hold the drum on (just like in a modern car) and that the drum can now come off by itself, separate from the hub. Surely there can't be a problem with having welded the studs rather than swaged them in, because remember the steel hub locates onto the cast iron drum in the centre, not via the studs. So the welding has exactly nothing to do with anything structural, because the studs are were already tightly countersunk into the hubs BEFORE they were welded (by the high tensile nuts we used). Some people have subsequently told me that the studs should always be swaged in rather than welded, but I can't logically see why the way I have done it is not perfect, other than that it is not original (but cast iron drums are not original anyway, right?). I drove the car at 55 mph and it is 100% smooth. The brakes are nice and sharp but there is a judder at very low speeds, but I am hoping that will disappear as they get run in? I have been using my car as a daily driver for 15 years and have come across many old wives tails and I am suspecting that the maxim that the studs must under no circumstances be welded is also one of them. Looking forward to your comments? Many thanks for reading this long post.

[1955cj5]

bof·fin
ˈbäfən/Submit
nounBRITISHinformal
plural noun: boffins
a person engaged in scientific or technical research.
"a computer boffin"
a person with knowledge or a skill considered to be complex, arcane, and difficult.
"he had a reputation as a tax boffin, a learned lawyer"

[Synchro909]

I recently posted of how some guys here had done exactly what you have done. I was howled down by some and ignored by others. I think mostly by ignorant people who aren't able to think for themselves.
While what you have done is not as Henry did it, it is fine and you will drive as far as the car will take you on those with no trouble from them, just as my friends have although there is no real need for any more than a tack of weld. One of those welds on each stud would have been enough.
BTW, the guys here have put a countersunk set screw in through the drum and into the hub just to make sure the drum goes on in the same orientation each time. Doing what you have done also makes inspection of brake linings soooo simple.
Feed back on this will be interesting.

[Chris Van]

Hi Synchro.... thanks for your reply. Encouraging indeed. Let's see what other opinions transpire.

[Kevin in NJ]

Not really a recommended practice.

You would have been wise to ask the question here first. You will find hundreds of these cast drums are all being swaged onto the hubs with no issues.

[quickchange]

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We used to do that on our speedway cars , Now the question , if new studs which are designed to be swaged they have a longer shank, will your nuts bottom out before they pull up tight , best check that , not really recommended but ?? Derek in a hot summers day in NZ back from our 6500 mile cruise across USA, no place like home,

[Bob C]

The the studs are counter sunk into the hub and swaged for a reason. There is a good chance that the emergency brake linkage pins will hit the weld, you can see the line on your hub where they have been rubbing before.

Bob

[iverson]

nice improvement! Will save beating up your axles! as long as the drum fits snug to the studs and the hub is steel I would not try to weld steel studs to a cast iron hub

[Chris Van]

Hi iverson. Many thanks for the reply. I agree that swaging is first prize because it is original, but is there any valid technical reason that the way I have done it is inferior?

[Chris Van]

Hi Bob: Thanks, will check that out, although my welds do not stand proud.

[Chris Van]

Hi Kevin: Yes, it does seem that the swaging can be done into cast iron no problem and I should really have done that I suppose. But I still can't find a proper technical reason why the route I have gone compromises safety; it also allows the drum to be removed from the hub without removing the studs.

[BRENT in 10-uh-C]

Originally Posted by Chris Van

Hi Kevin: Yes, it does seem that the swaging can be done into cast iron no problem and I should really have done that I suppose. But I still can't find a proper technical reason why the route I have gone compromises safety; it also allows the drum to be removed from the hub without removing the studs.

The technical reason is rather simple by design. The hub on each axle is designed to be in a perpendicular and equal plane with the brake shoes. There is a machined surface on the hub that allows for the machined surface of the drum to be tightly matched to, and the drums are designed to have the bolt swaged to properly tension and locate the drum against the hub so-as to keep the proper alignment to avoid chatter and/or a pulsating brake pedal (...which most would consider a safety issue affecting the proper operation of the braking system!). If you feel this swaging step is un-necessary in the proper operation of the Brakes, then please explain why Ford spent the extra time & expense for the machining operations on both the hubs and the drums, and the same operation time on setting up and swaging each of the hub bolts.


(Please remember that the Ford Model-A was not an over-built vehicle, however it was a thoroughly built vehicle based on the engineering technology available at the time of manufacture. Therefore, if Ford took the time or added expense to perform an operation, there was a substantial reason why they felt the operation was needed. The operation of swaging drums was important enough they even discussed it in the Service Bulletins for his Service Agencies. )

[tinman080]

Drive it....In the popular and economic outlook of the times when these cars were built I believe the studs were made to be replaceable over the life if the vehicle. The ''throw-away mentality'' did not exist. Even today the studs are pressed in, who wants to throw an axle shaft or sealed bearing hub away if a welded stud is damaged? If a parade or light duty vehicle is modified in a responsible and professional manner I personally say Drive it. Over a 40 year career I saw several vehicles (not so old) with individual studs that had been welded. MY opinion- NOT posted for debate. Gary

[updraught]

>>Please remember that the Ford Model-A was not an over-built vehicle, however it was a thoroughly built vehicle based on the engineering technology available at the time of manufacture.

What did other manufacturers do at the time?

[Railcarmover]

Had a hub with welded studs on it, given the wear on the brake shoes behind the hub the weld held up for years, and did the job, which is to prevent the stud from turning.One thing I did notice was the weld itself did not have good integrity, when I knocked out the stud the weld broke at the point where the weld meets the parent(hub) metal, indicating the crystallization of the hub steel not penetrated by the weld.Thus, in my estimation welding the hub greatly reduces the integrity of the hub steel.In my case, the weld performed adequately but not structurally. Basically, if the lug nut works loose the weld can fracture..

You cite "expertly argon welded" the issue I found has nothing to do with the shielding of the weld, which is what argon does in a MIG procedure.Its the mismatch of the filler metal and the parent metal, in this case the parent metal not penetrated is degraded to the point of failure.

[DennisR]

I had cause to replace a couple of studs on my rear end and could not find a workshop to do the job without much sucking in of breath and disclaiming responsibility if it went wrong. A quick scan on Ebay got me a 30 ton press at a lot less than the quotes I had for a workshop to do the job, worked a treat and I still have a handy press for future use. As a matter of interest, reading thru the previous posts re. welding etc., would it not be better to tack the stud with a small braze instead of weld?

[jimalabam]

Remember this: " IF IT AIN'T BROKE, DON'T FIX IT". Henry Ford...

[Frank Miller]

Originally Posted by BRENT in 10-uh-C

The technical reason is rather simple by design. The hub on each axle is designed to be in a perpendicular and equal plane with the brake shoes. There is a machined surface on the hub that allows for the machined surface of the drum to be tightly matched to, and the drums are designed to have the bolt swaged to properly tension and locate the drum against the hub so-as to keep the proper alignment to avoid chatter and/or a pulsating brake pedal (...which most would consider a safety issue affecting the proper operation of the braking system!). If you feel this swaging step is un-necessary in the proper operation of the Brakes, then please explain why Ford spent the extra time & expense for the machining operations on both the hubs and the drums, and the same operation time on setting up and swaging each of the hub bolts.


(Please remember that the Ford Model-A was not an over-built vehicle, however it was a thoroughly built vehicle based on the engineering technology available at the time of manufacture. Therefore, if Ford took the time or added expense to perform an operation, there was a substantial reason why they felt the operation was needed. The operation of swaging drums was important enough they even discussed it in the Service Bulletins for his Service Agencies. )

Then why did Ford make the drums for my 49 so they slide on and off? Given clean surfaces I would think that the lug nut would serve the same purpose as long as the installer made sure the nuts could thread on all the way. Also the original drums were stamped steel so swedging would have been preferable to make it stronger.
The cast iron drum guy could really have made a fortune if he designed them to take the modern press in stud and made the studs as well.

[BRENT in 10-uh-C]

Originally Posted by Frank Miller

Then why did Ford make the drums for my 49 so they slide on and off? Given clean surfaces I would think that the lug nut would serve the same purpose as long as the installer made sure the nuts could thread on all the way. Also the original drums were stamped steel so swedging would have been preferable to make it stronger.
The cast iron drum guy could really have made a fortune if he designed them to take the modern press in stud and made the studs as well.

Frank, generally speaking, drums that slide on/off are 'piloted' in the center. A Model-A drum is located onto the hub by 5 bolts that have the shank swelled in a swaging process that permanently locates the drum to the hub. Since the 5 holes in a cast iron drum are not precision reamed, swaging the lug bolt compensates for this. Afterwards the drum is machined in a lathe so the shoe lining surface is in specification within the X and Y planes.

My final comment on this is; originally, new steel drums were installed onto hubs without the need to true the drum in a brake lathe afterwards. How many times do we find aftermarket cast iron drums that do not need to be trued in a lathe after being installed on a Model-A hub? If the drum is not correctly located and held into position, then how can the drum's brake lining surface be trued to the centerline of the hub??

[Dino's A]

Your problem started with your mechanic. If you want to remove studs so the new studs will fit tight, he should of drilled a hole in the old stud to relieve the swag pressure.

On WWII jeep drums we drill a 1/4" hole and then a 5/8" hole and it will be ready to come out.