Author Topic: under hood finish  (Read 2452 times)

janobyte

  • Hero Member
  • *****
  • Posts: 907
  • 1968 z/28
    • View Profile
under hood finish
« on: March 01, 2014, 09:42:41 PM »
I was questioned today about the proper finish under the hood, I'm sure I read the hoods were dipped in black primer than shot from the top covering the edges with paint. Now is 30% gloss an acceptable finish for under the hood sheen wise ? Or too much? Firewalls getting shot at that.

lakeholme

  • Hero Member
  • *****
  • Posts: 2241
  • *68-12D L30/M35*
    • View Profile
Re: under hood finish
« Reply #1 on: March 02, 2014, 01:10:18 AM »
I was questioned today about the proper finish under the hood, I'm sure I read the hoods were dipped in black primer than shot from the top covering the edges with paint. Now is 30% gloss an acceptable finish for under the hood sheen wise ? Or too much? Firewalls getting shot at that.

Nope... 60% gloss black underside of hood. 
Phillip
HNR-AACA, Senior Master
Charlotte Autofair, Sept 24-27, 2015
Southeastern Division Spring Meet Chair, April 9, 2016
Planning Sentimental Tour, June 12-17, 2016

janobyte

  • Hero Member
  • *****
  • Posts: 907
  • 1968 z/28
    • View Profile
Re: under hood finish
« Reply #2 on: March 02, 2014, 01:40:10 AM »
Thanks ,I'll let my body man know. I have both sources (laminated) for chassis and "engine compartment" finish per CHP and Skip Cain's article as well as the Camaro National's Seminar--could not find something as simple as under the hood--I know every finish down to every fastener but not that! It's getting re-assembled for the spray booth this week and he needed my decision  asap. thanks again.

lakeholme

  • Hero Member
  • *****
  • Posts: 2241
  • *68-12D L30/M35*
    • View Profile
Re: under hood finish
« Reply #3 on: March 02, 2014, 01:45:29 AM »
Thanks ,I'll let my body man know. I have both sources (laminated) for chassis and "engine compartment" finish per CHP and Skip Cain's article as well as the Camaro National's Seminar--could not find something as simple as under the hood--I know every finish down to every fastener but not that! It's getting re-assembled for the spray booth this week and he needed my decision  asap. thanks again.

I hear you! Sometimes, reading the index to a P&A is like reading another language...  ;D

JohnZ

  • CRG Member
  • *****
  • Posts: 4253
    • View Profile
Re: under hood finish
« Reply #4 on: March 02, 2014, 06:39:56 PM »
I was questioned today about the proper finish under the hood, I'm sure I read the hoods were dipped in black primer than shot from the top covering the edges with paint. Now is 30% gloss an acceptable finish for under the hood sheen wise ? Or too much? Firewalls getting shot at that.

ALL of the Chevrolet-furnished front sheet metal got the same basic primer application - from the "Assembly Process" paper..

<<"Sheet Metal Painting: All raw parts (wheels, brackets, etc.) and the front end sheet metal (hoods, fenders, lower fender extensions, header panels, front valances, radiator supports, inner fenders, etc.) went through a cleaning, degreasing, and hot phosphate system, then through a flow-coat booth where it was deluged with black primer from all directions and then baked.">>
'69 Z/28
Fathom Green
CRG

janobyte

  • Hero Member
  • *****
  • Posts: 907
  • 1968 z/28
    • View Profile
Re: under hood finish
« Reply #5 on: March 02, 2014, 07:32:40 PM »
So..when everyone talks % gloss is it an interpretation of GM's black primer ? With subtle variations for detail ? Probably asking a question I already know the answer to ( hate when people do that!)  just want to verify. Glad for the reply John ,you were there in April 68 when the Ash Gold Z was rolling down the line. Probably stuck out like a sore thumb.

Mike S

  • Hero Member
  • *****
  • Posts: 1272
    • View Profile
Re: under hood finish
« Reply #6 on: March 02, 2014, 07:44:38 PM »
 I would think that whatever the gloss % is of GM's reconditioning black paint it, that would be close enough.
That is what I am using. I have yet to see anyone use a gloss meter to determine the gloss % finish at a car show.
Without one then it's simply individual interpretation. I doubt GM cared much what the gloss % was for underhood mass production parts.

Mike
67 LOS SS/RS L35 Hardtop - Original w/UOIT
67 NOR SS/RS L35 Convertible - Restored

janobyte

  • Hero Member
  • *****
  • Posts: 907
  • 1968 z/28
    • View Profile
Re: under hood finish
« Reply #7 on: March 02, 2014, 08:33:17 PM »
Oh ,I agree. Before it got the Black Lacquer and chrome treatment in the engine compartment a few years back ,I seem to remember it all being uniform. Low sheen black and undercoating ! I was asked yesterday what I wanted purchased and replied same under the hood as firewall etc... then I wasn't sure. Chassis is getting done at home anyway ,he just needed verification before he starts spraying sheet metal.

69Z28-RS

  • Hero Member
  • *****
  • Posts: 2924
  • owner since 4-Apr-1976
    • View Profile
Re: under hood finish
« Reply #8 on: March 02, 2014, 08:55:05 PM »
I would think that whatever the gloss % is of GM's reconditioning black paint it, that would be close enough.
That is what I am using. I have yet to see anyone use a gloss meter to determine the gloss % finish at a car show.
Without one then it's simply individual interpretation. I doubt GM cared much what the gloss % was for underhood mass production parts.

Mike

I'm with you Mike; that's been my opinion and approach for over 30 yrs now..
Gary W / 09C 69Z28-RS, 72 B 720 cowl console rosewood tint
69 Corvette convertible, silver/black 350 hp,
60 Corvette white/red, 72 Corvette coupe, '70 Mach I 
90 ZR1 red/red #246, 90 ZR1 white/gray #2466
72 El Camino, '55-'56-'57 Nomads, '55-'57 B/A Sedan

janobyte

  • Hero Member
  • *****
  • Posts: 907
  • 1968 z/28
    • View Profile
Re: under hood finish
« Reply #9 on: March 02, 2014, 09:03:18 PM »
BTY , I appreciate the replies.

JohnZ

  • CRG Member
  • *****
  • Posts: 4253
    • View Profile
Re: under hood finish
« Reply #10 on: March 03, 2014, 03:40:34 PM »
So..when everyone talks % gloss is it an interpretation of GM's black primer ? With subtle variations for detail ?

That semi-gloss sheen may have varied a bit from day to day, but the key issue (in terms of restoration accuracy) is that all of the black-primered Chevrolet front sheet metal components should exhibit the same gloss; they all went through the same prime paint system.

janobyte

  • Hero Member
  • *****
  • Posts: 907
  • 1968 z/28
    • View Profile
Re: under hood finish
« Reply #11 on: March 03, 2014, 04:01:02 PM »
  That's what I passed on Saturday ,but wanted to double check. Don't want to be a conduit for misinformation. Going full circle I usually have to look no further than my own car for answers. Flat hood is upstairs in my shop and has been untouched since 69 when it was replaced with the "cowl inducted" Anybody want to guess what the color is on the back of the 68 hood :) Not you Jonn, you already know.

janobyte

  • Hero Member
  • *****
  • Posts: 907
  • 1968 z/28
    • View Profile
Re: under hood finish
« Reply #12 on: March 03, 2014, 04:33:56 PM »
And, just got off the phone with the paint shop...Mike ,Gary want to guess what he suggested?     Already had this conversation with him....he's been shooting them for almost 40 years ,I like assembly ,just do it like it's yours. That's why it's in there. Got a little "hmph" on the varying %'s of gloss anyway.

69Z28-RS

  • Hero Member
  • *****
  • Posts: 2924
  • owner since 4-Apr-1976
    • View Profile
Re: under hood finish
« Reply #13 on: March 03, 2014, 05:58:33 PM »
If he didn't tell you 'GM Reconditioning black', I'd be disappointed.  :)
I've used some other paints, regular black urethane (with flattener) even flattened IMRON, but I've never gotten or seen the 'exact' perfect sheen with anything as well as the GM Reconditioning black.

janobyte

  • Hero Member
  • *****
  • Posts: 907
  • 1968 z/28
    • View Profile
Re: under hood finish
« Reply #14 on: March 03, 2014, 06:45:28 PM »
Saw some pics of cars shot with it when searched--that's what I want. Clean-straight and uniform.