Lug bolt swaging?

T

TechNova

Member
I purchased a new pair of drums and lugs for a 48. When I bought them the vendor said that the lugs press in and do not need to be swaged. The lugs are smooth and are not knurled like a modern car. I do not think they will work correctly by just pressing them in.
They are the hub on the outside of the drum style.
Do you think they need to be swaged? How do I swage them?
 
TechNova said:
I purchased a new pair of drums and lugs for a 48. When I bought them the vendor said that the lugs press in and do not need to be swaged. The lugs are smooth and are not knurled like a modern car. I do not think they will work correctly by just pressing them in.
They are the hub on the outside of the drum style.
Do you think they need to be swaged? How do I swage them?
Click to expand...

You can buy from most vendors that also sell drums, a tool to swedge the studs. You also have to have the correct studs that are made with a sholder that gets swedged. It also takes a BIG Press. Most home type shop presses are not big enough. I would go back to the vendor and have him explain how just pressing in the smooth studs will work.

Chris
 
I have access to a large press.
What does the proper stud look like?
I can also try to find knurled studs, there are a few old service stations here that still have the old drawers full of studs.
 
Why do you not trust the knowledge and word of your supplier? Just because a surface is smooth and not corrugated does not mean the stud will not perform the same. In fact it may be the case you will acheive even greater holding power as there is more surface area in contact.
Then again...
 
Fe26 said:
Why do you not trust the knowledge and word of your supplier? Just because a surface is smooth and not corrugated does not mean the stud will not perform the same. In fact it may be the case you will acheive even greater holding power as there is more surface area in contact.
Then again...
Click to expand...

I don't believe it will hold better for a rotary motion when putting on and off the lug nuts. If you have ever put in knurled lugs you will see they cut grooves into the hub when pressed in making them next to impossible to rotate.
It wouldn't make any difference in strength driving down the road.
Every car I have replaced lugs on from the 60's until current models has had knurled studs. I have replaced hundreds of them that were knurled.
The Model A and early Ford are the only smooth ones I have seen, they were swaged from the factory. A vendor saying his smooth lugs need no swaging
goes against everything I have seen.
Doesn't mean it's impossible, just reason to double check.
 
It seems like you have the drums that mount UNDER the hub flange, so the flange is visible with the wheel removed? If so, this is what they call "problematic." The new drums for this application (made in South America?) are entirely of cast iron, incuding the centers, which are thicker than on the original drums. Accordingly, original studs will be too short to swage against the exposed hub as were the originals. The originals are in fact smooth and without any serrations and DO NOT have a "flat" on the head to bear against a ledge on the hub once installed. Apparently Ford relied on "extreme pressure" of the swaging process to keep them from rotating??? Anyway, I have seen cases where the heads of the too-short studs have been tack-welded to the drum itself to prevent rotation, but this does not secure the drum to the hub as did the original studs.

In this case, attempting to use serrated studs will not be satisfactory BECAUSE it is not acceptable to press the stud into the cast iron drum center, and the drum center is between the stud head and the hub flange, making it impossible? to press the stud into the hub flange without first passing through the drum center. Would have to relieve the drum holes to eliminate pressure on the drum center (which could lead to cracking) which would allow the drum to "work" on the studs.

At the risk of over-stating your problem, when faced with this situation myself
I have always come to the same conclusion - that I was (choose one) ...
Original "inny" hubs and drums are very nice parts when the original drum is usable, but are a major PITA when it comes to replacing the drums. Another
possible issue (used to be this way; not sure if it still is) is that many years ago, these foreign drums had EXTREMELY uneven thickness of the shoe surface, causing them to be WAY out of balance - the machined part was not
centered in the casting... Because of this I have never used or sold these drums. I am not sure if the condition still exists??? EZ enough to check...

Others may have a different solution that I am not aware of??? Good luck!
 
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Richard, thanks for a good explanation of the problems with the inside-mounted drums.

Now, for the OUTSIDE mounted drums, I thought the repro drums also have cast iron centers and have the "too short" stud problem. What is the solution for those?
 
John R said:
Richard, thanks for a good explanation of the problems with the inside-mounted drums.

Now, for the OUTSIDE mounted drums, I thought the repro drums also have cast iron centers and have the "too short" stud problem. What is the solution for those?
Click to expand...

On the outside-mounted drums, we re-size the holes in the original hubs (and also the drums on one end) and press longer serrated studs into the HUB FLANGE; then the drum slides over the studs without any stress on them. We also grind flats on the stud heads that bear against the original ridge or boss on the inside of the hub flange. The original studs that require swaging CANNOT be used, as it is not permitted to swage against the cast iron drum center. To do so will void the warranty and can stress the drum and result in cracks around the holes in the drums. Besides, the original studs ARE too short...

Regarding the inside-mounted drums; been thinking about it during lunch... Possibly could find some serrated studs with long enough serration to reach through the thickness in the drum + hub, BUT would have to enlarge the hole in the drum so no stress on the drum center. This by itself will result in the drum being able to rotate slightly against the studs. The fix for that would be to drill 3 or 5 new holes through the drum center (between the stud holes), then drill & tap the outside hub flange to match and secure the drum to the inside of the flange. Would have to go through a "stud" catalog and find something suitable... BUT if the foreign drums are not of acceptable quality, that would be an exercise in futility. Have you inspected yours???
 
Looking at the drums from two vehicles I have here, I see where several studs have been replaced and the new studs have a spot of weld on the rear or them to hold them and keep them from rotating. Seems to have worked. Is this a bad idea?
 
Gary in Mozarks said:
Looking at the drums from two vehicles I have here, I see where several studs have been replaced and the new studs have a spot of weld on the rear or them to hold them and keep them from rotating. Seems to have worked. Is this a bad idea?
Click to expand...

If the studs will remain in place and not be able to rotate, the lug nut
and wheel will hold them in place. Not the best arrangement, but
sometimes have to do what you have to do to get down the road...
 
Gary in Mozarks said:
Looking at the drums from two vehicles I have here, I see where several studs have been replaced and the new studs have a spot of weld on the rear or them to hold them and keep them from rotating. Seems to have worked. Is this a bad idea?
Click to expand...

With the NEW Cast Iron (inside style) Drums, you would be welding the head of the steel stud to the Cast Iron Drum. I am not in favor of this arrangement. The original Ford Drums had a stamped steel center and a cast iron outer ring for the braking surface. Welding the studs to the original stamped steel center is OK.

I would see if you can find some good (Drum on the Outside) hubs and get the new cast Iron Drums for them. Will the seller of your drums exchange them? Also, try to use AMERICAN MADE DRUMS if you can. Much Better!!!!

My Opinion.

Chris
 
forever4 said:
Are you using grey iron drums instead of ductile cast iron? Also, the hubs should be steel, not grey iron. I am not familiar with the construction and materials being used on replacement V8 hubs and drums now. Original ductile cast iron drums like 32-34 are swedged directly. You will not crack a proper ductile cast iron drum.
Click to expand...

The drums from M/T are ductile cast iron, not grey iron. Nonetheless, the mfgr discourages swaging the studs due to the risk of cracking. Also, to my knowledge, there are no "swagable" studs available that are long enough to pass far enough through the thicker cast drum center and expose enough material to swage.

The mfgr also believes, and I agree, that it is an advantage to have the drum slip on and off, as it makes servicing the brakes easier, especially the rears.

All things considered, I do not see any advantage to swaging, and if there is any risk of cracking, that is too much risk for me. I do not wish to have to fight that fight...

The new hubs are cast steel, and therefore it is acceptable to press
serrated studs into the holes. We also convert original hubs to press-in serrated studs. Because the originals have either a boss or a ring that keeps the original studs (which have a flat on the head) from rotating, we grind a flat on the new stud so that it will clear the boss or ring, and also we are not depending on the serrations alone to prevent rotation.
 
Richard (EV8G) said:
The drums from M/T are ductile cast iron, not grey iron. Nonetheless, the mfgr discourages swaging the studs due to the risk of cracking. Also, to my knowledge, there are no "swagable" studs available that are long enough to pass far enough through the thicker cast drum center and expose enough material to swage.

The mfgr also believes, and I agree, that it is an advantage to have the drum slip on and off, as it makes servicing the brakes easier, especially the rears.

All things considered, I do not see any advantage to swaging, and if there is any risk of cracking, that is too much risk for me. I do not wish to have to fight that fight...

The new hubs are cast steel, and therefore it is acceptable to press
serrated studs into the holes. We also convert original hubs to press-in serrated studs. Because the originals have either a boss or a ring that keeps the original studs (which have a flat on the head) from rotating, we grind a flat on the new stud so that it will clear the boss or ring, and also we are not depending on the serrations alone to prevent rotation.
Click to expand...


I just noticed your signature, I was told to buy from you but didn't listen.
I am going to check the runout and may have a lug solution, checking an a few things the next couple days.
 
TechNova said:
I just noticed your signature, I was told to buy from you but didn't listen.
I am going to check the runout and may have a lug solution, checking an a few things the next couple days.
Click to expand...

Another solution to your problem would be to make a ring with the lug bolt holes and some additional holes for fasteners. Install bolts through the ring, then through the drum and then thread them into the hub flange. Install the studs through the ring/drum/flange and then tack weld the stud heads to the ring to prevent them from turning or falling out. This eliminates trying to weld the stud head to the cast drum.
 
Richard (EV8G) said:
Another solution to your problem would be to make a ring with the lug bolt holes and some additional holes for fasteners. Install bolts through the ring, then through the drum and then thread them into the hub flange. Install the studs through the ring/drum/flange and then tack weld the stud heads to the ring to prevent them from turning or falling out. This eliminates trying to weld the stud head to the cast drum.
Click to expand...


VERY GOOD IDEA,

I do this very thing when I mount Buick Aluminum Drums onto Ford Hubs.

Chris
 
I checked the castings and they both look good. I was mfg. engineer in a brass foundry/ machine shop for about 5 years so I know a little about the concerns of core shift or poor machining. I checked the runout by mounting them in a brake lathe, locating off the 4" center and using a dial indicator on the braking surface. I had .044" runout. There is sufficient material there to clean this up more.
I showed the parts to a retired John Deere factory maintenance worker.
He is well known for his machine repair skills. His suggestion was to use the smooth studs but to sandblast the smooth portion. Ream the holes in the drums and hubs to about a .005" interference fit. This would eliminate the chance of cracking the cast iron. Use Loctite Press Fit Retaining compound when pressing in the studs.
He is knowledgable in cars and motorcycles as well as tools and equipment so I trust his opinion.

This is for the rear drums, am I correct that if there was a failure by any method and a lug nut could not be removed because the stud spun, that the drum, hub and wheel could be taken off as an assembly????
The owner is not likely to ever change a flat herself, a flat bed will be dispatched.
 
Did you leave a zero out of the .044"? That seems like ALOT - hopefully you meant .0044??? The oversize limit on those drums should be about .060" unless they say 12.090" on them??? (The USA drums do) By the way, we mount the new drums on the hub that they are going to live with and then machine the drums to be sure the shoe surface is not eccentric. We then put
registration marks on them so if removed to service the brakes, they can be
reinstalled on the hub in the same position.

The method of installing studs that you mention probably would be ok (yes, can remove the wheel/hub/drum together worst case) except that I myself
would prefer to have a margin so that problem could not occur - will not be very convenient no matter who has to deal with it... and they may not know that they have that option. I would fix it right, fix it once...

Question: Will the "smooth" studs that you have be long enough to provide enough threads for the lug nut so that 3 threads extend past the nut??? If they
were made for original drums, the new drum centers are thicker...
 
Richard (EV8G) said:
Did you leave a zero out of the .044"? That seems like ALOT - hopefully you meant .0044??? The oversize limit on those drums should be about .060" unless they say 12.090" on them??? (The USA drums do) By the way, we mount the new drums on the hub that they are going to live with and then machine the drums to be sure the shoe surface is not eccentric. We then put
registration marks on them so if removed to service the brakes, they can be
reinstalled on the hub in the same position.

The method of installing studs that you mention probably would be ok (yes, can remove the wheel/hub/drum together worst case) except that I myself
would prefer to have a margin so that problem could not occur - will not be very convenient no matter who has to deal with it... and they may not know that they have that option. I would fix it right, fix it once...

Question: Will the "smooth" studs that you have be long enough to provide enough threads for the lug nut so that 3 threads extend past the nut??? If they
were made for original drums, the new drum centers are thicker...
Click to expand...

Yes, I'd say that extra 4 makes a difference. If I remember correctly the runout is supposed to be .005" max for drums.
I was advised to mount a 16" rim on the hub/drum and torque the lug nuts if I plan to turn the drums. I find it hard to believe the rim would make a difference considering the thickness of the hub and the amount of torque.
I have found a local parts store that has a small arbor for the brake lathe to do the rear hub/drums, my buddy can only do the front.

I am not concerned about the method I'm using for the studs, I was merely asking after thinking about some of the other methods posted such as welding to cast iron. Any method does stand some chance of a failure, I have had to cut a few lugs off modern cars, next to impossible without ruining some aluminum rims.

There are sufficient threads. They will be Model A rims with closed lug nuts. Measuring shows AT LEAST one full thread beyond the diameter of the stud. I measured conservative so it is actually more.
I have noticed some lug nuts have a counterbore or lead at the beginning that has no threads. Being selective in buying the right nuts looks like it could make the difference of a couple extra fulll threads.
 
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