66 Bumpers, original or repros?

[Jay G.]

Ok now that I know that these are rear bumpers, how can I tell if they are originals. Using a micrometer I get .102 to .109 for thickness.

[Michael G.]

Re: 66 Bumpers, original or repros?

Ok now that I know that these are rear bumpers, how can I tell if they are originals. Using a micrometer I get .102 to .109 for thickness.

Pic taken too far away to make any visual assessmemnt.

[Bruce B.]

Re: 66 Bumpers, original or repros?

Try and PM Ron Lovelace, he can verify the proper thickness of those bumpers.

[Ronald L.]

Re: 66 Bumpers, original or repros?

#1 as Mike says, too far away, need non flash close up of top surface

#2 Need to take more measurements, fast glance would be consistent to post 1988 stampings pre pargone

[Gary B.]

Re: 66 Bumpers, original or repros?

Ron,

If they were made by Paragon, shouldn't there be a PR stamped somewhere on the inside or on a bracket?

Gary

[Jay G.]

Re: 66 Bumpers, original or repros?

Ok , here are some more pictures, hard to take pictures of chrome. I measured in six different places and came up with the following, .90,.92,.98,.94,.98,.95bumperb.JPGbumpera.JPGbumperd.JPG

[Gene M.]

Re: 66 Bumpers, original or repros?

Jay
Off a decimal point?
Even if .090" - .098" a bit thin for a mid yr bumper ..........

[Jay G.]

Re: 66 Bumpers, original or repros?

senior moment on the decimal point. I'm beginning to believe that these are not originals. When I purchased the car these were extras, along with other parts that were replaced.

[Gary B.]

Re: 66 Bumpers, original or repros?

Jay,

If you suspect they are repros, then they are likely made by Paragon. If so, give Paragon and call and ask where to look for their PR stamping.

Gary

[Dick W.]

Re: 66 Bumpers, original or repros?

There have been more than one supplier than Paragon for the repro bumpers. I personally know of two more and think there are at least two-three more. Originally two different companies were sourcing them from the original GM tooling, one being of better quality because of the metal finishing work done after the cores were stamped. There have been at least one offshore manufacturer also. Thin bumpers make me think of offshore sourcing

[John H.]

Re: 66 Bumpers, original or repros?

There have been more than one supplier than Paragon for the repro bumpers. I personally know of two more and think there are at least two-three more. Originally two different companies were sourcing them from the original GM tooling, one being of better quality because of the metal finishing work done after the cores were stamped. There have been at least one offshore manufacturer also. Thin bumpers make me think of offshore sourcing

Dick -

Paragon still uses the original GM draw dies, but the GM trim dies have deteriorated long past the point of being economically rebuilt; the GM trim dies have been replaced with a robotic laser-t r i m m i n g operation.


MidYrTrimmed800.JPG

[Ronald L.]

Re: 66 Bumpers, original or repros?

.10 is consistent to when they went to run these mid 80's, before Paragon got a hold of the tooling.

Looks like John's been to Livonia. BTW that laser trim will be what is noticable as well, you won't have the sheared jagged back edge.

But then again, nothing looked like the original, starting with running this with the original steel.

[Dick W.]

Re: 66 Bumpers, original or repros?

Dick -

Paragon still uses the original GM draw dies, but the GM trim dies have deteriorated long past the point of being economically rebuilt; the GM trim dies have been replaced with a robotic laser-t r i m m i n g operation.


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The quote to rebuild the dies was well over $250k 20 years ago.

[John H.]

Re: 66 Bumpers, original or repros?

Looks like John's been to Livonia.

Yup -

I spent two days at QMC with Chet and Kerry back in 2008 photo-documenting every step of both the C1 and C2 bumper manufacturing, welding, metal-finishing, and plating processes for a feature article I wrote in "Corvette Enthusiast" magazine. With all the handwork involved, especially for the '58-'62's, it's amazing that they make a dime on those bumpers.

[Gene M.]

Re: 66 Bumpers, original or repros?

Measurement of 3/32" is too thin to be original. The drawing process yields thickness thinner at the deeper draws and less effect on the flat edges. Should be around .110" to .120" depending on where you mic it. Of course the plating adds thickness of around .006" give or take. Take more often. Replaters do a heavy finish compared to GM of the 60's. A plating on the inside surfaces will measure thicker.