Quality control can be a big factor. When molding nylon, you have to account for shrinkage of the material as it cools. Cutting manufacturing cost by reducing cooling time in the mold to shorten cycle times can yield parts with out of tolerance dimensions. It wouldn't take much to increase the friction on the axles and armature if the hole are only a tiny amount smaller. Significant performance hit with a nearly imperceptible difference to the factory worker.

 

I know with model kits. when you get a kit that is an old design. Allot of times there will be a ton of flashing were the molds leaked. Ive had kits with flashing so bad it was bigger than the part itself on the parts tree. Thats what makes me think it wasnt a tooling problem, but a "bang um out" to make quota problem.
Anyways its probably a question noone can answer but wonder what heppened to the original molds. Would be nice to see a company get ahold of them and fix um up and start popping out Tjets in the original recipe.

 

A lot of times I "deduce" what I think the truth is (ie I make stuff up).

A lot of times it turns out to be closer to the actual truth than what folks that were there first hand are presenting as the truth.

In this case I am thinking you are probably pretty close, TJetter.

Still, pancake fans have it pretty good with all the selections available. The Dash chassis looks to be better than the oem tjets.

 

IF the original molds are still in existence. They are likely very badly corroded, or damaged by now. People care for tools that make money. No one cares for outdated stuff that isn't profitable. By the time the HO market recovered and they became valuable again. It was too late to use the dilapitated tooling.

Between Dash, Wizzard, TFX, and the Fray. Pancakes are alive and well. AW and MEV still make nice bodies.

 

The last piece of the puzzle as to why the old molds can't be used anymore. Machinery gets updated, better, and faster every year. You'll probably need the equivelent of a 1959 Edsel injection molding machine that is slow and labour intensive to make use of the old molds. I bet the old molds can't put out any reasonable quantity in a profitable time frame. The new injection molding systems have new and improved coolant systems and channels running through them that speed up the process.

 

Nah, you should be able to clamp up old molds just fine. Newer machines have better computerized controls, but the process has not changed much. For most materials, you are actually heating the mold with water flowing through internal passages. For Nylon 66, you would have at least 150°F mold temperature.
When products are discontinued, it is not uncommon for molds to be destroyed to prevent unauthorized parts from being produced. I would be vey surprised if the original Aurora molds still exist.

 

Aurora Barn Find!

 

Sweet!

 

The earliest T-Jet cars were assembled and tested in the US before they were packaged up and shipped out. Later the rolling chassis were assembled in Asia and case loads of them were sent to the US where bodies and guide pins were installed before the cars were sold. I recall that Ed Bianchi wrote a story about the search for lost Aurora tooling called Raiders of the Lost Slots. Since the chassis were made in Asia the tooling was probably scrapped there. The tooling for the bodies would have been in the US and was likely scrapped after Aurora folded up.
REH, a major distributor ended up with most of the unsold rolling chassis, I expect that great care was not taken of them. The last of the T-Jet stuff was sold to Slot Car Central fairly recently.

 

Hum Im only an hour from slot car central and surprisingly Ive never gotten there.

 

[QUOTE="Tjetter, post:
sounds like a place i would like to visit

 

[QUOTE="Tjetter, post:
sounds like a place i would like to visit

Me Too.........unfortunetly it hasnt happened yet.

 

I doesn't seem to me that the original molds are really that special. Given how many chassis they made, and how many different cavity marks that appear on T-Jet chassis, it seems like they probably made and used up many different molds.

It strikes me that the overall attention to detail and quality control, along with the quality of rest of the parts that go into a car, matter much more than just using the original molds.

And with modern 3D scanning and CAD tools, you can pick your favorite chassis and use it make a very nice brand new mold. The molds that Dash and Wizzard are using seem to be working pretty well.

And I'm guessing that the molds that Auto World is using are probably just fine, even if the overall quality of the product is terrible.

Another detail is the plastic. None of the current T-jet reproductions use the same plastic as the original. But it seems like that's by choice. I have to assume that one can still buy the same type of plastic that Aurora used, but they have chosen to use something else.

Maybe @Steve-E-D has some thoughts about why the reproductions don't use the old plastic formula. Is it just more convenient/easier/cheaper to use a more "typical" plastic that the mold shop is familiar with? Or maybe there are some additional complexities associated with the original formula? Or maybe the newer types of plastics have some better properties that just make the chassis better?

 

The hitch with making reproduction chassis is that they will tend to shrink when they are ejected from the tooling. Dash had a major problem with that when the original T-Dash car was introduced. The shrinkage was not taken into account and a different plastic had to be used to get chassis that could be sold. Newer Dash cars use redesigned tooling and seem to use the common type of plastic.

 

HDK: "Is it just more convenient/easier/cheaper to use a more "typical" plastic that the mold shop is familiar with? Or maybe there are some additional complexities associated with the original formula? Or maybe the newer types of plastics have some better properties that just make the chassis better?"


Yes. All of that, no doubt.

Then there's what I call the idiot, or obvious factor. Almost two decades of good success using nylatron, across multiple designs. Hmmmmmmm

Then some rocket scientist comes along and fixes it to shave some nickels, cuz they know it all.

The "WHY" isnt always conveniently illuminated.

 

If you look at even original Aurora chassis. the plastic seems to differ between some. Some look like they have a grain to them, almost like a fiberglass hair look, then some are more uniform grey plastic looking.

 

If I had to venture a guess, I might think that better dimensional stability would be the biggest reason that I might try something other then the traditional Nylatron. I know I would feel more confident sending a tight tolerance molding job out to a budget off-shore molding shop.
This would really be a question for Dan at Dash to weigh in on.

Tyco obviously ran down another material path with the TYCO PRO.
AW chassis appear to be a glass filled nylon variety.