195 replies to this topic

[swodem]

Why?

[MSwiss]

I think Tony meant the USRA one, not the NZ one.

 

Of course, not an issue if it's not intended to run at the USRA Nat's.

[tonyp]

Exactly.

[MarkH]

Depending on the number to be stamped, it will be a ton cheaper on the tooling to have the blanks laser cut and then form the bends with the punch press die. The forming section of a multi stage punch press die will last longer than the cutting sections. There must be draft below the cut line to allow the slugs to drop out to the scrap bin. Each time the die is sharpened the distance between the cutting edge of the punch and the die grows. Generally it is 10% of the thickness being stamped or .004" here. At some point the gap becomes big enough to cause the edge to roll and break off instead of cutting. Some where around 15-20%, or .006 to .008" problems could start to show themselves requiring more investment to correct the issue.

Keep in mind it will take several regrinds to get there but it will happen.

 

With the laser cut blanks the tooling to form the final product will last a LONG time.

IMHO, if the chassis is stamped to form the final product it should be good to the regs. I am sure opinions will vary.

[MSwiss]

"Stamped and formed" sounds like 2 different processes.

 

JMO

[MSwiss]

For kicks, I Googled "stamping die".

 

The first answer that wasn't an ad, was;

 

Die Basics 101: Part I

 

and said;

 

What Is a Stamping Die?

 

A stamping die is a special, one-of-a-kind precision tool that cuts and forms sheet metal into a desired shape or profile.

[Samiam]

Stamping (also known as pressing) is the process of placing flat sheet metal in either blank or coil form into a stamping press where a tool and die surface forms the metal into a net shape. Stamping includes a variety of sheet-metal forming manufacturing processes, such as punching using a machine press or stamping press, blanking, embossing, bending, flanging, and coining.^[1] This could be a single stage operation where every stroke of the press produces the desired form on the sheet metal part, or could occur through a series of stages.

 

Key words being: "placing flat sheet metal in either blank or coil form into a stamping press". The blanks are laser cut then "stamped and formed" into the final shape. So IMHO....this chassis conforms to USRA rules.   

[Phil Hackett]

I'm sure that USRA rule was created to keep EDM chassis from being legal. EDM is still an expensive process. Laser/water cutting is a fraction of the cost of EDM and allows far more flexibility in production over hard tooling (punch and forming dies) and the direct costs are much lower than hard tooling too….

 

I'm glad someone looked it up: punching a piece of metal to desired dimensions, whether it's a "blank" or continueously punched from a roll of material is *forming*.

[MSwiss]

Stamping (also known as pressing) is the process of placing flat sheet metal in either blank or coil form into a stamping press where a tool and die surface forms the metal into a net shape. Stamping includes a variety of sheet-metal forming manufacturing processes, such as punching using a machine press or stamping press, blanking, embossing, bending, flanging, and coining.^[1] This could be a single stage operation where every stroke of the press produces the desired form on the sheet metal part, or could occur through a series of stages.
 
Key words being: "placing flat sheet metal in either blank or coil form into a stamping press". The blanks are laser cut then stamped and formed into the final shape. So IMHO....this chassis conforms to USRA rules.

 

Sam,

You extensively edited your post since I last read it.

You seem to keep ignoring it says "stamped and formed".

It doesn't say "stamped and formed. (Chose any one or both of the above)".

Regardless, if it is submitted, it's up to an USRA official to interpret the rules.

If it is determined to be OK, it will be just that much easier for JK to counter with something better.

With not being restricted to the piece having to be punched, the Czech All-Star Chassis Design Team will have an X26, X27, X28, X29 and X30 for JK to sell to the racers, and let them decide which of the five or more new versions most suits them.

I've been immersed in this for the last 30 years, and the result is always the same.

Grey area guy always gets trumped by bigger resources, better designers guy.

When I came out with the below pictured, laser-cut, and formed, hot rod chassis, I considered for about two minutes to do a similar chassis, for the flexi market.

I quickly realized it would never fly.

With lasered blanks being allowed, and the resulting unlimited fine cuts being possible, as in my hot rod design, just think what the Czechs, or any other good chassis designer, could come up with.

[kvanpelt]

Sure hope Matt doesn't let the horse out of the barn. It won't be pretty, unless you like buying the latest greatest chassis of the week.😠

[Samiam]

For kicks, I Googled "stamping die".

 

The first answer that wasn't an ad, was;

 

Die Basics 101: Part I

 

and said;

 

What Is a Stamping Die?

 

A stamping die is a special, one-of-a-kind precision tool that cuts and forms sheet metal into a desired shape or profile.

 

It says "stamped and formed" not "stamping die".

[Samiam]

But what do I know. All I did was stay at a Holiday Inn Express last night.

[swodem]

Ok so we spent a day at our flat track with two of these chassis. Can get them quick but not quite as quick as X25. It's a little stiff, which is a benefit and a fault in different areas of the track. I'm assuming that it was designed with fast banked King tracks as the primary usage?

[Koford fan]

We have used X-25 for some time now, in addition we have worked with it, straighten things out... the more you work with it, the better it gets

[mrslotcar.ca]

Hi All
 
The USRA rules states that it must be a stamped steel chassis in order to be legal.
If we are to trust Wikipedia as our source for definitions, it also says that under the umbrella of "stamping" there are included 12 different possible operations.
 
What I think is important here is to limit the cost of these chassis. As ISRA has done this year when the governing delegates approved the Patriot Striker into use for 2016. The USRA rulebook does not appear to address this issue
 
After all, we should be focusing on the primary limiting factor that governs an individual racer's choice, cost; not discussing ad infinitum the nomenclature surrounding the manufacturing processes in such nauseating detail.
 
If we're all proponents of making this hobby grow, we should all look to the beginner racer. Probably most of us in this thread have been racing longer than we can remember, so we might tend to lose sight of what's really important
 
Ernie Mossetti
Mossetti Racing
Designer of World Championship and National Championship winning chassis since 1992

[Samiam]

Any plans for a 4.5" or a F1 version?

[MarkH]

Ernie, to your point, using the term "Stamping" is about the same as saying "Racing", Partying, Vacation etc., can be described with a single descriptor set. They are general terms categorizing a subject. This is not much different than saying "Car".  To some this might be an Automobile, Train Car or Roller Coaster section.

 

I have been in the Machine shop world since 1978. A lot of it building punch press dies or repairing them. Worked my way through job shops, manufacturing plants and specialty products type of companies. After 11 years finally earning the title of "Toolmaker". However, as most know, the title means nothing more than referencing a relative level of skill sets. In no way I am declaring to be an expert of all Machining or Manufacturing techniques. Those who do make that claim should be held to task before accepting their "Expertise". If one talks to 3 machinist/toolmakers about the correct process to use to make a part, while some of the core principles will be followed, you will most likely get three different answers. This is only because the terms Machinist / Toolmaker cover a huge spectrum of disciplines that make up the whole. Much like the term "Stamping"

 

In my experience, punch press dies, regardless of type or number of stages, were referred to as "Dies". This again may vary depending on the discipline and geographical location of those making the reference.

 

It seems that the descriptors used for the Flexi car in the rules have their origins based upon the understanding of the technology available at the time pen was put to paper or a continuation of tradition. If these rules were designed to keep cost down then I would submit they need to be updated to reflect current affordable technology. Should it be deemed using laser cutting and forming dies technology is legal and adopted as a universally accepted rule, the flexi world would benefit greatly. Sure you will have some new designs that will outperform current designs but that is merely moving us forward. The "Chassis of the Week" argument would quickly run its course by the manufacturers themselves. It would make little sense to release a product that obsoletes this years release.

 

Just thinking out loud. Opinions will vary……………...

[Tom Thumb Hobbies]

"If we're all proponents of making this hobby grow, we should all look to the beginner racer- Probably most of us in this thread have been racing longer than we can remember - So we might tend to lose sight of what's really important. "

Ernie, I couldn't agree more. Perfectly worded.

[Rob Voska]

If you put a piece of steel into a press and it performs "work" is it not a die?  Does it matter the shape of the steel "blank" that is used before it is formed?  All a progressive die does is cut away the scrap in the early stations (making a blank) and forming rarely starts before all the cutting is finished.  Do dies make parts from blanks one at a time, coil strips, precut pieces of material or all the above?  I have seen dies that are both progressive in the first few stations and change to transfer (individual parts) at the later stages.  I have seen multiple presses set up to cut blanks then another press forms and a third punches holes & trims the edges and the material is hand transfered from one press to the next.   

 

Take a chassis to a fabrication shop & have a die quoted.  Whoever quotes it will ask how many do you need.  That answer is what determines the manufacturing process.  Tolerances, delivery, cost determines manufacturing process. 

All these things need balanced to determine the way forward along with a thousand other questions that need answered before the first move is made.  Even the design often changes to aid the manufacturing process.

 

What I see is now is there needs to be dimensions on a chassis because the program could be changed to alter the "blank" design slightly with no tooling cost involved.  Matt Bruce is a great guy & well versed in manufacturing so I think the USRA will get this one right.

[Greg VanPeenen]

Sure hope Matt doesn't let the horse out of the barn. It won't be pretty, unless you like buying the latest greatest chassis of the week.

 

Right, Flexi racing will become just like Retro. LOL.

[swodem]

I think the important difference between a stamped or formed chassis and a straight laser cut chassis is there is no assembly required

 

All uprights (pin tube and axle) are bent, guide tongue formed etc

 

As against a flat laser cut chassis that comes in 20-odd pieces...

[MarkH]

Any more testing results?

[swodem]

From me? May get more testing done tomorrow...starts to get secret from here...

[MarkH]

Ahhhh, secrets just mean to me there is potential. Sounds like it is pretty good anyway. I would be happy just knowing the relative performance to the X25.

Thanks

[swodem]

About 1/10th slower on our flat track with a lap speed of low 4.4's and LMP body