BUICK DRUMS-Better Method (?)...Solved MY Issues!

Well, girls and boys, it's finally time to sit down and put this info and pictures into a technical thread of sorts, in the hope that the info MIGHT help some of you address some particular issues I wanted to address on MY '40 Ford coupe. First, a little background. I've owned and built quite a few old Fords and also restored several old Corvettes over the past 47 years. Since 1964, I've wanted a '40 coupe but that just never happened until 1997 when I bought a street rodded coupe with a beautiful body. I knew that the underpinnings and details weren't what I wanted, and I've spent the past 13 years collecting parts and changing things to make this coupe into MY car, something like the coupe I wished I could have built around the '63-'65 timeframe. Anyway, one of the major things I wanted to change was the front brakes this car had on it. The previous owner had put Chassis Engineering disc brakes on the '40 spindles, which included the '70-'77 Camaro discs which had been adapted to the '40 spindles. Frankly, they never stopped like they should have because of a mis-match of parts to go along with the disc installation. One of my criteria was to end-up with 12" Bendix-type, self-energizing drum brakes that could have been used on a hot rod back then. Another of my criteria was to end-up with a 5 x 4 3/4" bolt pattern, as I wanted to run Chevy chrome steelies which I already had. In addition, I wanted to run a brake that was easily adaptable to the '40 spindles. SO......after not too much thought, the 45 fin Buick drums became a fairly obvious choice, not because of the "COOL" factor but because they are still available, they are 12" by wide, they ARE traditional hot rod material, and because they are obviously adaptable to the Ford spindles by at least two or three well-known methods. I thought about the "new" Lincoln backing plates. Also knew a little about the old mid '50s F-250-12" backing plates, specifically that they bolt-up to the spindles, and that they had been "adapted" to work w/Buick drums. So, I actually found two pairs of '55 Ford F-250 plates in short order. Sure enough, they bolt right up to the spindles, look good, all the parts are easily obtainable from NAPA, and they're actually authentic, old parts. Most, if not all, of the adaptations of these backing plates to use with the Buick drums that I had seen usually involved some type of interference between the plates and the lip at the rear of the Buick drum which required some surgery on the Buick lip to solve the interference. One well-known guy's "new" adaptive hubs didn't seem to solve that problem because his hubs mount the drum INSIDE the hub flange, moving the drum too far inboard, resulting in the drum lip hitting the F-250 backing plate. In addition, I wanted REAL studs, pressed into the flange...not spot-welded bolts. Also, I wanted the look of the drum mounted on the outside of the hub's flange, without all those other unnecessary bolt pattern holes showing. Plus, those hubs ain't exactly cheap, especially when ya don't end-up with exactly what ya wanted it to look like in the first place. On top of all this, the adaptations of the Buick drums to OLD FORD HUBS have their own problems, especially when changing the bolt pattern to anything other than 5 x 5 1/2". RIGHT NOW might be the time to tell all of you that IF you are not going after a 5 x 4 3/4" bolt circle, this EXACT process won't work for you, as you'll see a little later based on the EXACT HUBS we ended-up using. Keep in mind, I kept fighting with this "look", and the spacing problem with the Buick lip being too close to the backing plate. Still scratching my ass, I started measuring the "in-out" spacing, with regard to the wheel-mounting surface, of the originally adapted Camaro rotor disc. Hmmm, maybe we're on to something here. That surface actually sits farther OUT on the spindle than the same flat surface of an old Ford hub when mounted on the same spindle. Did some more quick n' dirty measuring on the Buick drum with the F-250 backing plate mounted and DAMN...this is gonna work. You say: What the hell is this idiot talking about? Picture a disc brake rotor in its entirety. It's nothing more than a disc which is glued onto the rear side of a hub, a pretty substantial hub, to boot. So I'm thinking, if we can cut the disc off of the hub, we can glue the Buick drum on the outside face of the new, disc-less hub. The Buick drum is now spaced-out properly to clear the backing plate, AND I also have the Chevy (5 x 4 3/4") bolt pattern I want already manufactured into the hub, with press-in studs...no welded bolts or such. Of course, there are some minor details that we haven't discussed YET with regard to properly mounting/adapting the Buick drum, but if you'll follow this thing through to the end, there will be mucho-plenty of pictures and explanatory BS to get the point across to y'all.

My biggest problem now is that there is SOME machine work involved, both on the Camaro disc rotor AND on the Buick drum, and I ain't no machinest and I certainly don't have the equipment. I DO have a good grasp of the machine work necessary and how to approach this project. I live in the Houston area and one would think, correctly, that there must be a gazillion machine shops around here. So, I ended-up contacting three different shops. One didn't want to screw with this "hair-brained" idea. The other two didn't impress me with their ideas on how "simple" this little project would be to "throw-together". So, in the back of my mind I remember a friend in Salt Lake has a son I had met on a trip to Bonneville a couple of years back. The son is none other than Brian Thomas, aka HOT ROD PACKARD here on the HAMB. I knew that Brian was an accomplished machinest, and I knew that Brian understands "hot rod". So, I e-mailed Brian with a precise explanation of what I wanted to do, and why. He e-mailed me back and said only: "Send the shit. I know what you want". Brian is sometimes a man of few words, but believe me, HE knows his shit. I sent him a pair of new Camaro rotors, a pair of pretty nice (not worn-out...only .025" oversize) Buick drums and a handful of new studs. Brian put his heart into this project. Everything he did entailed precision, straight and beauty. Every step of the way, he was thinking nine steps ahead. In fact, these things ALMOST turned-out too pretty to hide behind a wheel. Follow along on this thread (I've never posted something like this before...bear with me) and hopefully, some of you can put some of this to good use. Please understand that HOT ROD PACKARD gets ALL the credit for this beautiful end product.

Pictures: #1 These are the '55 Ford F-250 backing plates.
#2, #3, #4, #5 This is the Camaro rotor in the lathe, parting the rotor
from the hub. #5 shows him chamfering the rear side
of the "new" hub flange.

 

Front, rear or either backing plates?
I took a break from roofing the milk house and wow, this is timely and interesting.

 

OK, the outer bearing snout on the hub where it meets the flange has a straight, machined surface which is slightly larger in OD than the snout itself. Brian was going to make two (two drums and two hubs) indexing rings to center the drum on the hub. The ID of the center hole in the Buick drum is larger than the OD of the machined surface on the center snout on the hub. He machined these two rings out of a piece of raw stock. He ended-up sizing the ID of the ring a very few thousandths smaller than the machined surface of the hub snout for an interference fit. He cut the OD of the indexing rings a couple of thousandths TOO LARGE for an interference fit in the ID of the center hole in the Buick drum. Once he had sized the ring stock he made a chamfer cut on one inside edge of each ring. This chamfer is to clear the small radius at the transition between the flange and the machined, mounting surface on the snout so that the ring will fit flat against the flange when pressed-on. The next five pics will show Brian machining these two rings.

 

I'm using front backing plates. Some confusion as to whether rears are usable or not. Fronts CAN be found. Have patience. And, many more pics to come! DD

 

Here is one of the finished rings being heated slightly before being pressed onto the machined surface of the snout. Note the chamfer, which goes to the inside and against the flange. Both rings installed on the two hubs. The surface of the aluminum DRUM with the large hole in it where the drum will eventually mate with the hub flange is quite thick, something over 1/4" as I remember...much thicker than the same area of a comparable STEEL drum. Here you'll see Brian heating the vertical face of the drum at the center hole to slightly expand the hole for the interference fit over the indexing ring. When he does slide the drum on the hub, he's careful to index the drum on the hub with the five original Buick lug holes "clocked" half way between the CHEVY 5 x 4 3/4" holes in the hub. This is important for the "new" bolt pattern which still remains to be drilled in the drums. It's also important for the permanent attachment method of the drum to hub which is still to come. Final pic in this batch shows the drum pressed onto the hub via the indexing ring, from the back side. Look closely and you'll see the chamfer on the rear side of the hub flange which he did in the first batch of photos.

 

Putting this together is slow-going for a HAMB neophyte like me. Hope you all can bear with me. There's still more good stuff to come. Anyway, the next few shots show Brian making a fixture so that he can clamp each assembly to the table on his mill to finish the rest of the machine work, which essentially includes drilling and tapping the hub through the original Buick bolt pattern stud holes. You'll note three bolts which are temporarily clamping the drum to the hub to make them "as one" for the next machining operation. The THREE holes he used for this are the ORIGINAL holes that were used to rivet the Buick drum to the BUICK hub. The bolts are kind of skewed through the three rivet holes and into three of the five holes in the hub that will eventually become the CHEVY 5 x 4 3/4" bolt pattern that we're going for. The final shot in this batch of pics shows him countersinking that thick aluminum for the countersunk machine screws that will bolt the drum securely to the hub. More to come...

 

The first pic in this batch shows the five countersunk machine screws installed and tightened which effectively make the drum and hub one piece. Next, he mounts the drum assembly in the lathe to FACE the wheel-mounting surface so that the wheel runs straight with the world, in other words, no chance of wobble. Next, you'll see him drilling through the CHEVY bolt pattern hub holes THROUGH to the aluminum drum wheel-mounting surface, so that he can now install the new studs. Next, he TURNS the drums to make sure the shoe surface is true to the world. In this shot, it's not hard to notice HOT ROD PACKARD's beautiful, famous ol' Hot Rod Magazine cover car in the background. Many of you who have seen this car in the flesh know what a craftsman/genius Brian really is.

 

In this last batch of photos, we see the finished product, both front and back...beautiful! Next, we see one of the drums mounted with the backing plate...and it turns WITHOUT rubbing on the backing plate. Finally, we see what this looks like, ready to bolt a wheel in place. Just want everyone to know that I put a little thought into the WHATS and especially the WHYS of doing these this way. Brian put the expertise, knowledge and precision care into making it happen so well. You'll note that the end product turned-out with NO extra holes like you see so many times when a drum has a new bolt pattern drilled into it. Brian's forethought made this happen the way it did. He DOES have his shit together. Many thanks, Brian.

I hope that this might help someone that might have a special situation that just hasn't quite figured out A particular way to do it, yet. DD

 

Excellent presentation and clearly documented.

Frank

 

Very, very nicely done..........both the engineering and execution!

Ray

 

I had to read it several times while looking at the pictures but it all made sense. Nice contribution to the Hamb. Looks cool to boot!

 

Frank, Ray and Kevin...Sincere thanks for the kind words above. Sorry this piece started out so long-winded, BUT...I thought it most important to explain the WHYs of this project for it to have any real merit. DD

 

Very well done tech piece! Thank you very much.

 

Nice tech. I've done this a couple times using the hubs from riley auto.

 

Nice tech piece. The finished product looks awesome. Very well thought out and executed. Super impressive.

 

Great idea DD, that's a neat innovative way of doing it! I did a similar set up on my '32 pickup using early 50's F-1 pickup hubs inside the drum but I did have to redrill the hubs to the 4 1/2" bolt pattern I was using. I would think your idea would work equally well with 4 1/2" Ford/Mopar discs too. This is a great way make do without searching for those hard to find early Ford hubs. Thanks for teaching us it never hurts to use your head and take a different path! That's what Hot Rods are all about!

 

Are the steelies you're going to use hub centric too? Do they fit the hubs now, or will you need some sort of centering ring for those too?

Nicely done solution - a lot of work but at least you found the right guy to do it. Looks like the reults will be well worth it - and maybe the brakes will work too!

 

Cudos to Brian for fantastic work!

And, DD, don't worry about your thread being too long. Every tech thread should be writen this way! Not only do I want to see what people do, but I also want to know why. Excellent!

 

very innovative, great tech article. I only had to read it once; made perfect sense. and oh yea, they look awesome!!

 

Excellent article!! Easily read and good pics. I need to get my Buick drums done...

 

Awesome tech piece, thanks for taking the time to put it together for us.
Your final product looks awesome also!

 

Dick, glad you got to this and wrote it up. Was my intentions but you kow how people get busy with shit, so it never happend.
I do believe its better said by you any way!

Nice to see them on the car finally.

I still have all the pictures and maybe even more. Very good job!!!

 

I read it all . My eyes hurt now , but it all made perfect sense ! Plus this is the kind of craftsmanship we see comming out of the "Asshole Garage,Machine Shop " on a regular basis. Well Done all around !

 

Really nice work. I understand your motives but I've done over 50 Buick drum conversions using stock 46/48 hubs, Wilsons hubs and Waldens hubs and have no issues doing them that way, plus I'm lazy and they require much less machine work. The Wilson and Walden hubs have multiple bolt patterns and are already machined to fit the drum. Just a little cleanup on the rim of the Buick drum + truing and your set.

 

First of all, ladies and gentlemen, I'd like to take this opportunity to once again say a gi-hugic THANK YOU for ALL the kind words that have been written about this collective effort between Brian and myself.

It needs to be mentioned here that the BUICK DRUM topic can cover a huge number of DIFFERENT ways to incorporate them into a "hot rod" build. There must be something near a hundred different combinations of available parts and combinations of said parts that have been done over the years. Each and every one of those combinations, all the way from the simplest Buick drum used with stock '48 backing plates mounted on an old Ford spindle with 5 x 5" bolt pattern, right on up to Buick drums mounted on F-1 hubs with a 5 x 4 1/2 bolt pattern with Buick backing plates, including all the other known combinations and possibilities in between...you have to realize that there is virtually an endless number of possible combinations out there to put Buick drums on an old Ford spindle. Believe me folks, I have perused the HAMB archives on this subject for over three years now. Believe me again when I say that I've read them over and over. There IS a wealth of information on SOME of the ways to do this, BUT some of this info leaves more questions than answers. I also find that some of the threads are started with a question by someone that indicates that the person asking the question probably has no idea of ALL the important questions and engineering considerations he or she HAS NOT asked. Hey, we all got into this hobby not knowing squat...ME included. Point I'm tryin' to make here is that when considering using a piece of automotive stuff, like a Buick drum on some other application than the front of a '65 Buick, a huge number of parameters, options and considerations MUST come into play. WHAT type of backing plate would I like to use? WHAT type of hub will I use? IF not OLD FORD, how will I adapt it to the spindle? WHAT type of bolt pattern do I want? WILL that bolt pattern work SAFELY with the HUB I think I want to use. I am a firm believer in doing NO MACHINE WORK on inner or outer hub snouts that may weaken their integrity with the flange. I've seen guys machine these back toward the center of the hub to facilitate using a smaller diameter bolt pattern, and that's just scary. DO I want to use factory engineered wheel studs or GRADE 8 bolts threaded into a hub then tack-welded to hold my wheels on? Lastly, WHAT do I want the finished product to look like...LOTS of extra, empty, threaded holes in between those tack-welded bolts on my hub, OR clean and finished, no extra holes, and with the flange on the inside? Keep in mind that virtually every one of the most commonly-used backing plates mounts with differing degrees of inboard OR outboard offset, ALONG WITH regard to the differing degrees of DRUM offset, inboard or outboard, depending on HOW you mount the drums.

In the end, I know down deep that this technical piece will only be of any possible use to a significant few. For the rest of ya, hopefully some entertaining reading. I'm sure that hundreds of ya never got past the first, boring paragraphs before the pics started. By looking at the counts, THOUSANDS of folks never even clicked on this thread...NO interest=NO clicky. That's all understandable. I only put this together to try to show ANYONE with some interest in the subject, that there are a multitude of considerations that need to be taken into account, and that we had come-up with only ONE method of doing this swap using MOSTLY traditional parts, all the while implementing the 5 x 4 3/4" pattern. DD

 

Really well done I have been looking at doing something similar with Ford hubs. Now I just might do it.

 

Hey Fairlane...Just jot down all the reasons you have for doing the project. Then jot down all the optional details, like bolt pattern, backing plate choice, etc. Take your time and measure, measure and measure. Try to borrow parts to mock-up or take dimensions. Always keep an open mind and look at the possibility of PLAN "B", or even PLAN "C"......whatever necessary. DON'T cut corners, and be patient. You can do it, but try to think your plan completely through before getting started. Go for it! DD

 

Hi everyone..I just got my buick brake drums today..first of all thank you dd Coopman for posting this info. This is exactly what I needed. I am building a 1933 Chevy 5 window and would like the chevy bolt pattern to mount my artillery wheels... However, my question is what year front camaro disc brakes were used in the process? Any info would be appreciated.

 

They were '70-'77 Camaro rotors. Got 'em brand new from O'Reilley's next day. Seems like they were either $33 or $36 a pop. DD