Packard Forum Index » General

Quote:


Kev, My 51 does have the padding between the cross brace and the hood skin.

The name of the "plastic" die material was Kirksite OR some reasonable phonetic speeling of the name.

But Kirkcite was strictly for short runs. It would not hold up to hi production of say over 1000 units and stamping was very slow compared to steel dies..

Kirksite did not come into exisitence until about 1965 or thereabouts. Usual, Kirksite was used to make a 'mold' from and original part and not hand crafted to some new design.

Maybe someone can google Kirkcite or some close spelling to that name and find out more.

When I worked in the foundry (early 60s) we used Kirksite in place of wooden patterns because the pattern would last longer. It did not have the shrinkage that normal metals experience when cooling from a molten state. I inquired as to its origins and was told it was invented by a fellow named Kirk during WWII. I made a pair of loco sideframes out of it and still have them.
If Packard was using Kirksite for a die material and it wasn't invented till 1965 then they were probably using it on that V12 they were making.

Thanks to Brian's Service index, and a nudge from him in the right direction I present to you this STB on the subject of Hood Flutter and Hood Buckling:

https://www.packardinfo.com/xoops/html/downloads/STB/50T-43.pdf

This was found by going into the 51-54 Service Index, and clicking on "Fenders and Sheetmetal". This listed the various topics on that subject. So much better than blindly looking from multiple years of STBs and SC's. Plus I am not sure I would have ever thought to look in the 1950 STB set, where this one was found.

Brian, do you think the above STB is also applicable to 55-56 Service Index as the hood is similar? Just curious?

Kev -

You bring up an interesting point that deserves a little background.

First and foremost, the index merely echoes the (vehicle) Application information as published in the article, where provided. When the application wasn't obvious, I inferred it from the time frame of the bulletin and working backward from any part numbers referenced or any other tell-tale information. Out of over 600 topics for the 51-54, there were some four dozen gray areas that took a lot of extra effort to resolve, but there are still a couple of entries that remain unresolved.

Yet, I digress...

Now, there were some cases where I took it upon myself (and based on personal experience) to extend application of a topic into the 55-56 Index, but it's hard to say where to stop doing that - at the risk of overextending yourself and being wrong. Mind you, though the 55-56 cars are a derivative, I'm not anywhere near as familiar with the 51-54 cars and have no examples at my disposal for inspection.

So, I took the route of generally recommending (via the introductory text) that the user take a look at bulletins listed for similar models from earlier Series and weigh the applicability.

Getting back to STB 50T-43, I don't think you could interchange hoods between the 55-56 cars and 51-54 cars with a perfect fit, the are probably close enough (especially WRT to the rear panel support) that the bulletin may be applicable. However, I've not encountered such problem on any of my V8s. IIRC, everyone of my cars (that wasn't mouse-chewed) had some felt installed there.

Though the 24th Series hood carried over into the 54th Seies, this information was never cited or reiterated in subsequent years. Could this have simply been a "new model" issue - for the sake of transition from the 48-50 style? I didn't check to see if the topic was covered in the 51-54 shop manual (my bad).

If enough people think the topic needs to be in the 55-56 Index, I can easily add it (thanks again to your programming).

Kirksite is a low melting temperature metal alloy used for making dies. It has the advantage that it is easily molded into a die, but it has the disadvantage that it wears out quickly. A Kirksite die might be good for 100 parts where a tool steel die will make many thousands.

Kirksite comes into its own for making prototype parts quickly or when you wish to make a small run of parts without the expense of a permanent die.

In the case of the hood scoops they probably made a small die of just the scoops and used it to press the scoops into a standard hood stamping.

I don't know when Kirksite was invented but it was definitely being used in the auto industry in the late 1940s.

Today there are high strength plastics that will do the same job.

the hoods will not interchange due to the difference in the radius used on the top of the grille. the entire front clip however WILL.

Well I was not saying that the hood interchange, just that the STB could apply to the 55/56 models also since the hood hinges and the rear structure of the hood is similar.

oops! duh, my bad!

A followup to the Kirksite and "plastic tooling" comment. A snippet of info from Collectible Automobile, Aug 1998 in an article about the early Corvette.
"At the time of the Waldorf show we were actually concentrating on a steel body utilizing Kirksite tooling for the projected production of 10,000 units for the 1954 model year. Kirksite dies are faster and cheaper to make than conventional ones but have a shorter working life..."
A steel-bodied Corvette???
That explains why Packard could tool a new hood die for the 1956 Caribbean which was only supposed to have 500 units, 250 of each convertible and hardtop.