OK, back from vacation and finished and installed second hinge . . . glass works beautifully and Mama's happy now!

I took a good look at the original hinges and there are several signs that they are actually sand castings. If I'm right about that, it would explain the lack of an original die (mold) which is what is normally used to make reproduction parts.

The sand mold would have had three inserts, one for the large hole at the pivot, one for the recess with flats that recieves the glass mount button, and one for the part number . . . . . which explains the recess there.

The thru hole and counter bore for the glass mount bolt were machined in a secondary operation.

Also, it is possibe that the end (where the glass mounts) was bent over after the part was cast in another secondary operation.

The bend is around 4 degrees, while the angle of the face is 2.25 degrees . . . odd.

The mold parting line on the back side was cleaned up by hand probably on a belt sander in yet another secondary operation.

Making an exact reproduction would be . . . . interesting . . . to say the least.

I am going to make a second set of prototypes with some design changes that should reduce the machining time and improve the fit at the slots in the interior.

This part is much more complicated that it looks at first glance. After getting into it, I can see why nobody has reproduced it. CNC for this part is correspondingly complicated. It will require either several setups or jigs (expensive) or a sophisticated mill and an extensive program (also expensive) to produce.

So far, I don't see the volume to justify CNC, but we'll see.

Without getting to technical what is CNC?I'll still be happy with what you are making now.At this point I don't care about cosmetics.I just want to open my window

Copter;

CNC is an acronym for Computer Numerical Control. It basically means a machine that is controlled by a computer instead of a human operator.

Parts made by these machine tools are less expensive because the machines turn out parts 24/7 and each part is precise.

But unfortunately, you can't just show the part to the machine and have it start spitting parts out of a slot . . a fairly complex program must be created to tell the machine what to do. The really big machines are 5 or more axis and can change their own tools and to some degree make changes to the part setup, but the more capable the tool, the more complex (read expensive) the program becomes, to there is a trade off.

If you're only making a few dozen parts, it would take longer to get the CNC program written, debugged and tested . . than to just make the parts manually. Also, somebody has to pay for that program, which will cost the same for 2 parts as for 10,000 parts.

If you designed the part using solid modeling software, most if not all of the CNC code can be generated automatically, but only after you've spend a ton of money on engineering to design the part in the first place.

Die casting is the fastest production method, but there again you need the die (mold) . . which cost many thousands of dollars to make.

I think the original hinges may well be sand castings . . . . i.e. almost no tooling cost, but fairly costly to produce. GM certainly could have made dies or created CNC code . . . . that tells you something.

The first hinge took about 8 hours to make and the second took 4. And I have a LOT of design hours in this. I would have made a set of hinges for my wife in any case, so I'm not looking to recover engineering time for the prototypes.

I've made some design changes based on the first prototypes which should shave time off and produce a better looking and fitting part.

If I can get the time down to around three hours per hinge, I can make sets for $300 for whoever wants them, but there will be a wait. You can be first in line if you like, since you've been following along and giving feedback.

I doubt I will produce any latches as the machine time would be excessive. The latch (not the pin on the window) is an assembly of several parts, a spring, etc. The pot metal part of it (the part that you bolt down) on my wife's car has a lot of wear in the oblong hole where the misaligned pin just chewed away at it.

The latch works fine, just looks bad. It would be simpler and faster to repair it than to make a new piece.

Steve, first off, this is the 5th topic you have started about the hinges, would you mind using this one from now on, instead of starting a new one every-time. Some people subscribe to these threads,and don't check back her that often, instead they rely on an email when it gets a new reply, when you start a new one, no one gets the email....Plus it's just bad forum etiquette to start more than one thread about the same subject...

Your hinges are now in the $300 range, is this going to be permanent, or will the price drop as you get farther into the production?
I really want a pair of hinges, but will have to save up some more for the new price....

Oh, and welcome back from vacation, I hope you had a good one!!!

_________________
Arizona Corvette Enthusiasts
Gone, but not forgotten

Hmmmm...... That's as max as my budget will let me get any now. Any higher I will have to decline on getting any.

DAWG is right about keeping to one thread onn this.

Please keep us posted and thanks for the work.

_________________
C3VR Lifetime Member # 51
NCM Lifetime Member #1353
Iron82

Sorry about multiple threads. I don't know much about how forums work.

Remenber that the $150 price was for a local machinist with a CNC setup to make at least 50 sets from steel. At the time, neither of us had seen a hinge off the car and therefor did not know about the special machinng needed in the face to accept the glass button.

I said I would make the hinges and I did that. But there is not enough interest to justify production. I think there were about 8 definates and 10 'interested' so there isn't much I can do at this point.

I still want a pair!!!.My latch is fine but was just starting to look bad because of the pins.The previous owner noticed this and didn't use it much.But yeah just let me know when and where to send the money.I do have some questions about mounting the hinges.It looks like they can be installed one side at a time?Also what problems did you have with the defog wireing?I might even need an instruction sheet.I'll have to look in my assembly manual or my shop manual and see if they break it down. The CNC thing,I've seen them before just didn't know that was what you were talking about.I can see where it would be $$$ for the progam.I've seen the at work and they are fast and everyone looks the same. Doesn't Foose use one when he makes his rims?

No prob Steve, everyone is a newbie at least once....


I will still want a set, just put me on the bottom of the list, need time to recover from getting the second kid in college this summer...

Copter;

OK, you'll get the first set available, that's a promise.

As to installation, I did one side at a time. Unhook the gas strut from the glass and lay it aside. Then close and latch the glass. The hinge then can be taken off and the new hinge installed. There are 4 bolts on the bracket side and a single allen button head screw up in a recess that screws into the glass button. You reuse the bracket, but I provide a new bolt. I'll provide more details later.

The rear window defroster is not conected on our car, so I don't have any info on that for you. It would be good if you posted back your installation experience.

Dawg;

Would a post in the 'big' hatch thread be a good idea? So that people who are waiting on an e-mail from that thread will know to check back?

Thanks,I will report back on the install.Do those hinge covers just pop off or do I even need to take them off?

Steve, I posted a link to this thread in it for you...

BTW, if you go through the other thread, theres at least 20 people that replied about wanting a set.

Did you put any thought into contacting Ecklers, Corvette Central, or Mid America about these? if it's like the original hubcaps, one of them might want to stock some of the hinges....

Copter,

Hinges are complete!

You and my wife will have the only two sets made from 1" thick stock. Only yours will be both 1" thick and have the new sleeker design.

Any future sets will be new design, but only from 3/4" thick stock.

I need to know if you want your hinges painted, your shipping address, etc. I will provide you with payment info via e-mail and I will post some pics tomorrow.

remove panties befor using this address:

steve@thecubestudiopanties.com

Thanks!! Just leave them plain.I'm not sure yet on what color I want.I might even send them out through work and have them plated.Anything I want.We build the Glufstream Jets and we plate what ever the customer wants,You name it polished or satin gold.Brushed nickel ect.E-mail at zgator@comcast.net and let me know what to do and how much.Thanks a bunch!!!Can't wait to see pics!!

I will post here what is of general interest and e-mail specifics.


You will receive new fasteners to use at the glass end and I'm also going to include new thin cork/rubber composit gaskets to cushion the hard metal end. Even though there is a plastic washer which you'll re-use, I want an extra measure of safety.

Re-use the bolt and bracket from the pivot end. I'll provide thin nylon washers to put between the bracket and the hinge to prevent rattles or wear . . . . after all, you will be using your hatch a lot now, right?

Check your e-mail for the rest of the information.

http://www.thecubestudio.com/pictures/Proto2a.jpg
http://www.thecubestudio.com/pictures/Proto2b.jpg

Dang Steve, they look good....