Finished prototype Mustang disc brake spindles

[63_Fairlane]

Jimminy Crickets you guys, he just got the first prototype cast and machined. Do you honestly think he's going straight to selling them without putting them on a car? What criteria do you need for road testing? A 30 minute drive thru town and on an interstate at normal highway speeds? Destructive testing, putting it into a hydraulic press with a gage on it to see how much strain is needed before it deforms or breaks? Or is that destructive road testing where he drives a car so hard until it breaks. Geez, give the man some time and opportunity to get to the point it's market ready first, then ask him what he's done and been thru. I for one, know how "rewarding" it is to have someone criticize what your doing before your even done. Now some on here are asking valid questions, but he did say this wasn't a racing piece, to use it as such you'd be doing so at your own risk. That said, I believe this piece will perform up to par or exceed the design(s) it's based off of, I mean we are talking about at least 20 years of metalurgy, process equipment, and testing advances.

It sounds like he is on the right track with the lab testing, but I would suggest finding the criteria currently used by Ford, GM, etc... Magnaflux, impact, bending load, Izod, Xray etc.... are just initial starting points. The part must be conditioned, subjected to high and low temperatures, salt spray, dust contamination, wheel loads, etc... and then re-tested in the lab to make sure that its properties have not been degraded.

As for racing versus the street, a pot hole or curve can produce a hell of an impact load compared to most billiard smooth raceways. The steady state forces in a race car will of course be higher, but the street is very tough on suspension parts. In addition, most street cars do not typically receive the level of maintenance that a race car will have between sessions.

Just an engineer's perspective.

By the way, good luck with the project.

 

[65mistress]

Just an observation, the majority of your consumers if you take these to market will be the ones who will feel warm and fuzzy from the use testing. The lucky few who know all about the xray testing and the metallurgy testing and the acoustic testing won't need it, but the masses will more then likely not know what any of these tests are for or how they are performed or how all that translates to a superior product that they should buy. John Q Public is going to be the touchy feely how-does-this-perform crowd. If you tell them, well I ran tests X,Y, and Z on it, that's not going to tell them how it reacts on the road. It's not going to tell them how it handles a fist sized rock hitting it at 80 mph and drives away with a minor scratch.

I'm not saying that these tests aren't good, heck I don't even know how 2 of the tests procedures go. I'm just saying that if these tests would be good, then adding road testing would be better.

Just out of curiousity, how many sets have you produced so far? It would probably be nothing at all to just put some on a car and drive it around for a month or so.

 

[1320stang]

I kinda went off before, I'm not going to be a patsy and edit it though. But some of the tests some of you are asking about are going to shoot the costs thru the roof and it's not going to be cost feasible. Marshall spoke of some welded lowered spindles he got from Fatman. Fatman has been in business at least 20 years and is pretty well known. I'm pretty sure most people that buy a product from them assume it's been tested and verified and go on without a thought. Others, like Marshall, see the product once they get it and say, no way is that POS going on my car. If I took a stock knuckle, made a mold and cast it using the same materials, the same methods, and the same criteria as the factory does, wouldn't it be reasonable to think it would stand up to the same testing and have the same fail rates as the factory piece? Maybe I'm not understanding it fully, but it seems that he is taking a knuckle and modifying it a little bit. He did say that the Granada knuckle was a modified version of the '70 Mustang knuckle, it's not like he's making something up from scratch. But it seems if someone makes a cast aluminum wheel spacer in the kiln in their backyard, by golly, let's slap her on and go road racing and it's all okay. I think he's posting it to guage interest. Maybe, hindsight being what it is, he shouldn't have posted it at all until he was done and ready to go to market with it. He's laying all his cards out on the table for you to see, he's not hiding anything.

 

[1320stang]

Just out of curiousity, how many sets have you produced so far? It would probably be nothing at all to just put some on a car and drive it around for a month or so.

I will be receiving these machined 65-73 prototypes this week! If specs are met production will start this month. Then on to the 65-66 specific model.

First post, sounds like he doesn't have any yet.

 

[degins]

I kinda went off before, I'm not going to be a patsy and edit it though. But some of the tests some of you are asking about are going to shoot the costs thru the roof and it's not going to be cost feasible. Marshall spoke of some welded lowered spindles he got from Fatman. Fatman has been in business at least 20 years and is pretty well known. I'm pretty sure most people that buy a product from them assume it's been tested and verified and go on without a thought. Others, like Marshall, see the product once they get it and say, no way is that POS going on my car. If I took a stock knuckle, made a mold and cast it using the same materials, the same methods, and the same criteria as the factory does, wouldn't it be reasonable to think it would stand up to the same testing and have the same fail rates as the factory piece? Maybe I'm not understanding it fully, but it seems that he is taking a knuckle and modifying it a little bit. He did say that the Granada knuckle was a modified version of the '70 Mustang knuckle, it's not like he's making something up from scratch. But it seems if someone makes a cast aluminum wheel spacer in the kiln in their backyard, by golly, let's slap her on and go road racing and it's all okay. I think he's posting it to guage interest. Maybe, hindsight being what it is, he shouldn't have posted it at all until he was done and ready to go to market with it. He's laying all his cards out on the table for you to see, he's not hiding anything.

Larry,

Exacty!

It may be a mistake to "lay my cards on the table" so early, but I had anticipated the issues that are being discussed and wanted to air my views and hear market concerns before the parts are made available. I will give due consideration to these concerns, but I will also keep in mind that the parts being offered are reproductions or iderations of current designs and don't need proof of concept testing. It is clear to me that some of the contributors to this discussion are, for the most part, showing off their learned opinions. These suggestions are impractical. These people would not be willing to pay for the cost of their suggestions. On the otherhand, I vow to withstand the considerable pressure to make a cheap part. Please note, I am only at the prototype stage, so production is a few months away. Sales will probably be direct only at first.

 

[1320stang]

Degins, what do you think about the trend to put giant diameter, wide rims on the fronts of these old cars that were designed for a 14x6 wheel? My dad always warned me about too wide a wheel/tire combo on the front end as it tended to wear bearings out and loaded the knuckle in a way it wasn't designed for.

My thought is, if a guy could design a knuckle for many different cars that used the same spindle (large) and therefore, the same bearings (large), and was beefier in the pickup points on the control arms, he might have something there. Of course, he'd have to design a rotor for it as well, but it'd be the same rotor no matter what make it was. And make that rotor so it could be cast in several diameters. The knuckle would have either common attachment points for a caliper bracket, or multiple attachment points for multiple common calipers. This is very general in principle idea.

 

[degins]

Degins, what do you think about the trend to put giant diameter, wide rims on the fronts of these old cars that were designed for a 14x6 wheel? My dad always warned me about too wide a wheel/tire combo on the front end as it tended to wear bearings out and loaded the knuckle in a way it wasn't designed for.

My thought is, if a guy could design a knuckle for many different cars that used the same spindle (large) and therefore, the same bearings (large), and was beefier in the pickup points on the control arms, he might have something there. Of course, he'd have to design a rotor for it as well, but it'd be the same rotor no matter what make it was. And make that rotor so it could be cast in several diameters. The knuckle would have either common attachment points for a caliper bracket, or multiple attachment points for multiple common calipers. This is very general in principle idea.

Larry,
Your dad was correct. I've discussed this issue before. The early mustang drum spindles were not only NOT designed to withstand the loads of 8" wheels, but were also not designed for disc brake applications. The Kelsey Hayes and all of the modern disc brake systems offered today for use on the 65-67 Mustang uses a bracket that bolts onto the drum steering knuckle (spindle). This knuckle was designed for a 10" drum brake. The 10" part is what is important here. The spindle pin, bearings and the underlaying stucture were engineered to withstand the rotational force from a 10" drum (5" lever). The bracket systems being offered today use rotors that are 11-13" diameter. A 13" rotor applies more twisting force on the pin and as does the 10" drum. Note that Ford greatly increased the bulk of the pin and structure starting with the newly designed disc brake spindle for 1970. They obviously realised the need for a purpose built bracket and a larger pin to support the loads of the 11" rotors being used.

 

[TT670]

1320, people arent putting on tires that are any wider or taller than theyve been using for the previous 40 years, sure the wheels might be a larger diameter, but the OVERALL diameter and width of the wheel/ combos being used today isnt much different than running a 14" 60 or even some 70 series tires in 1967. I truly think its not so much the wheel width thats the problem, but the backspace used by some and how they load the bearings. Brakes are a different situation altogether.

 

[skywalker]

My engineering background is pretty different (computer-engineering) but the principals are still the same and it sounds like his testing procedures are pretty damned thorough. He's reproducing (albeit with some very minor changes), using a superior preduction method, an already tested to death design. I'd say the test issues here are pretty much nil.

 

[69 Capecod]

Wow this is two pages of he said she said bull. Hes not inventing the wheel here hes just making a old part better. If you want to distruct test some thing then maybe it shouldnt go on a clasic mustang at all.

 

[HistoricMustang]

Kind of an interesting post just 4 months ago.

http://members.boardhost.com/MustangSteve/msg/archive/125408.html

Seems "degins" feels the way to go is forged !

"The webs we weave..............."

HistoricMustang
www.historicmustang.com

 

[Jester67]

Larry,
Your dad was correct. I've discussed this issue before. The early mustang drum spindles were not only NOT designed to withstand the loads of 8" wheels, but were also not designed for disc brake applications. The Kelsey Hayes and all of the modern disc brake systems offered today for use on the 65-67 Mustang uses a bracket that bolts onto the drum steering knuckle (spindle). This knuckle was designed for a 10" drum brake. The 10" part is what is important here. The spindle pin, bearings and the underlaying stucture were engineered to withstand the rotational force from a 10" drum (5" lever). The bracket systems being offered today use rotors that are 11-13" diameter. A 13" rotor applies more twisting force on the pin and as does the 10" drum. Note that Ford greatly increased the bulk of the pin and structure starting with the newly designed disc brake spindle for 1970. They obviously realised the need for a purpose built bracket and a larger pin to support the loads of the 11" rotors being used.

Not to nitpick but Ford offered 65-67 with Kelsey Hayes disk brakes and 11” rotors. That is what mine came from the factory with.

 

[TT670]

Kind of an interesting post just 4 months ago.

http://members.boardhost.com/MustangSteve/msg/archive/125408.html

Seems "degins" feels the way to go is forged !

"The webs we weave..............."

HistoricMustang
www.historicmustang.com

What a way to twist someones words, good thing its in print for the world to see. I dont see any indication in that thread of him feeling forged is the way to go.

 

[skywalker]

Kind of an interesting post just 4 months ago.

http://members.boardhost.com/MustangSteve/msg/archive/125408.html

Seems "degins" feels the way to go is forged !

"The webs we weave..............."

HistoricMustang
www.historicmustang.com

Only thing I see there is him saying most modern styles are forged. Umm okay...

I don't think many people will argue that forged parts are generally better. But there are cases when strength vs cost effectiveness leans towards cost effectiveness.

 

[degins]

Only thing I see there is him saying most modern styles are forged. Umm okay...

I don't think many people will argue that forged parts are generally better. But there are cases when strength vs cost effectiveness leans towards cost effectiveness.

I stand by what I said. I don't know historic, so I don't know what his problem is with me. Isn't it interesting how passionate and rude some people will get concerning things they have no real real interest in. Then again, perhaps they do!

skywalker,
The knuckles in question are designed in a way that would make forging very difficult, in that the shape is complicated. The forging would require many steps with multiple dies. Forging is not necessarily better. Forging inproves the crystalline structure of ferrous parts, which inproves the operative physical properties of the part. That said, there are other ways of inproving those properties, like using better grades of metal. Modern manufacturers use forgings because it allows them to make lighter stronger pieces. In 1966, the inexpensive product of mass production ruled. Big and heavy were a plus with customers. Today, quality engineering and refinement rule.

 

[1320stang]

Kind of an interesting post just 4 months ago.

http://members.boardhost.com/MustangSteve/msg/archive/125408.html

Seems "degins" feels the way to go is forged !

"The webs we weave..............."

HistoricMustang
www.historicmustang.com

I don't see him saying that forged is the way to go, unless your construing that since he says modern spindles are forged and he's doing his in 2005....

That's a long road to get to that though.

 

[jikelly]

This might be a bit off track considering the current testing issue you guys got stuck on. I have a 73 mustang which already has 11" disc brakes, but if a spindle was made that allowed me to upgrade to 13 inch rotors I'd buy it if I could afford it.

 

[Edbert]

Not to nitpick but Ford offered 65-67 with Kelsey Hayes disk brakes and 11” rotors. That is what mine came from the factory with.

Are you 100% sure of that? I thought the upgraded power-disc-brakes avalable on 65-67 GT/GTA models were 10-inch rotors, even with 15-inch wheels as in the Shelbys.

 

[Jester67]

Are you 100% sure of that? I thought the upgraded power-disc-brakes avalable on 65-67 GT/GTA models were 10-inch rotors, even with 15-inch wheels as in the Shelbys.

I’m never 100% sure of anything but the last time I put a tape on them I thought it was about 11” I will check again tonight if I get the chance.

 

[meanroy]

Cast vs forged

Kind of an interesting post just 4 months ago.

http://members.boardhost.com/MustangSteve/msg/archive/125408.html

Seems "degins" feels the way to go is forged !

"The webs we weave..............."

HistoricMustang
www.historicmustang.com

Ha Ha.
Historic, there is actually considerable question whether cast is superior to forged, even though the 2005 Mustang does use forged steering knuckles (spindles)
After degins corrected my faux paux regarding the factories process I dug around a bit.
There is a very good presentation on the advantages of each which reaches the following conclusions here:

Castings will tend to have a definite advantage over forgings when any one of three conditions is met:

* a unique metal composition is required;
* the part is relatively large or complex;
* stresses may be multi-axial.

This paper was presented at the Steel Founders Society of America. SFSA is a trade association representing steel foundries.

The Forging Industry Association agrees with this but adds:

Forging offers significant advantages over castings in applications where high reliability, high tensile strength or fatigue strength are required, frequently in combination with high ductility, impact toughness and fracture toughness. Forgings are free from porosity, which is difficult to eliminate in castings. This is particularly true in areas where geometric transitions occur, which are also areas of stress concentration.

So, to sum up, forging supplies improved fatigue strength with the disadvantage of anisotropic characteristics. In addition differential cooling of the forging due to variable cross sections forces additional heat treating to obtain uniform strength and brittleness which negates some of the advantages of the process.
So it seems casting may be superior to forging in this case if the correct heat treatment is applied because of the ease of obtaining equal strength in all axis. Forging still gains the best ultimate fatigue strength, but not in all axis.

Interestingly, both casting and forging sources state evaluating by test should be part of the design process.