• 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Cracks developing around hood fasteners
#1
Hi,

The paint on my '71 Mach 1 is perfect except one thing: on the NACA hood, cracks are developing around the twist lock hood fasteners. The cracks are mostly radial and 1/2-1 inch long.

I have made sure the fastener inserts are not binding in the hood cutout/opening and that the fasteners only fix the hood but do not force it up- or downwards.

Is this a common problem or can it be traced back to some kind of mistake made by the painter (the car has been professionaly painted)?
If it is caused by the painter, what arguments can I best use to have him correct the problem (he claims that this is a weak spot and that it always will develop cracks)?
Do you have any tips or tricks how to avoid the cracks during a repaint?

Thank you, Manfred
  Reply
#2
ManniB;20303 Wrote:Hi,

The paint on my '71 Mach 1 is perfect except one thing: on the NACA hood, cracks are developing around the twist lock hood fasteners. The cracks are mostly radial and 1/2-1 inch long.

I have made sure the fastener inserts are not binding in the hood cutout/opening and that the fasteners only fix the hood but do not force it up- or downwards.

Is this a common problem or can it be traced back to some kind of mistake made by the painter (the car has been professionaly painted)?
If it is caused by the painter, what arguments can I best use to have him correct the problem (he claims that this is a weak spot and that it always will develop cracks)?
Do you have any tips or tricks how to avoid the cracks during a repaint?

Thank you, Manfred
Thats a load of B.S. Post up a pic & i will tell you exactly whats going on.. (did they make the cut out for the twist locks?) & that's not the painters fault it's who ever did the body work prep


LOVE OF BEAUTY IS TASTE..THE CREATION OF BEAUTY IS ART
  Reply
#3
IMO: More likely the hood lock engagement was set too tight causing the sheet metal to "dimple" which over time will result in cracking. When I push down to engage the pins, the metal flexes just a little bit as they engage, but then it comes back to it's original profile - no dimple.
  Reply
#4
Bill73Ragtop;20330 Wrote:IMO: More likely the hood lock engagement was set too tight causing the sheet metal to "dimple" which over time will result in cracking. When I push down to engage the pins, the metal flexes just a little bit as they engage, but then it comes back to it's original profile - no dimple.
Bill...That' in it self won't cause crack's I can take a piece of metal that's prepped properly & sprayed properly & bend it back & forth without the paint cracking..His problem is too much filler applied in the area..poor quality primer...Incorrect reducers...mismatched materials....incorrect application of the top coat clear coat..with out a picture it's hard to say


LOVE OF BEAUTY IS TASTE..THE CREATION OF BEAUTY IS ART
  Reply
#5
QCode & Bill,

thank you for your replies. Although it was not that easy to take a picture that properly shows the cracks, I hope the one below is suffucient.
The painter has tried to "repair" the cracks by "flowing in" some paint with a brush which obviously didn't work.
Regarding the body work, I did the paint removal myself down to bare metal. I then sprayed it in primer to prevent it from rust. The body work has been handled by the same painter who did the top coat.
As I wrote in my initial post, I adjusted the twist locks such that they do not put any downward force on the hood. So they should not "dimple" the metal.

   
  Reply
#6
Although this is not related to the prep work or how to resolve the problem, I just wanted to give my two cents on the subject about fastening the lock too tight.
Even if you adjust them so that they don't put any pressure on the hood, it will dimple as soon as you go fast on the freeway as the wind will try to push the hood open thus pushing it up against the locks or pins.
I had that problem with mine.
Usually the metal is flexible enough absorb this and will go back to it's original shape once you go slower.
On mine, the dimples stayed, so I reinstalled the original hood lock and just keep the hood pins for looks.


Anyway, as Q said, this should not cause cracks in the finish!

[Image: 1z21rv4.png]

Mike

"If I were you...... I´d rather be me."  Tongue

Check out my video:
http://www.7173mustangs.com/thread-my-mustang-in-action

  Reply
#7
ManniB;20363 Wrote:QCode & Bill,

thank you for your replies. Although it was not that easy to take a picture that properly shows the cracks, I hope the one below is suffucient.
The painter has tried to "repair" the cracks by "flowing in" some paint with a brush which obviously didn't work.
Regarding the body work, I did the paint removal myself down to bare metal. I then sprayed it in primer to prevent it from rust. The body work has been handled by the same painter who did the top coat.
As I wrote in my initial post, I adjusted the twist locks such that they do not put any downward force on the hood. So they should not "dimple" the metal.
Looking at the picture it's a failure of the substrate or top coat...Did you use a 2k primer when you primed the car ? or lacquer ? did the painter remove your primer & re-prime ? How was the car stripped ? If it was chemical did you neutralize after stripping & then use a metal conditioner ? Also was the car painted in urethane ? & did you do a single stage job or base coat ..clear coat & what type of paint did you use..


LOVE OF BEAUTY IS TASTE..THE CREATION OF BEAUTY IS ART
  Reply
#8
[quote=luxstang;20382]
Although this is not related to the prep work or how to resolve the problem, I just wanted to give my two cents on the subject about fastening the lock too tight.
Even if you adjust them so that they don't put any pressure on the hood, it will dimple as soon as you go fast on the freeway as the wind will try to push the hood open thus pushing it up against the locks or pins.
I had that problem with mine.
Usually the metal is flexible enough absorb this and will go back to it's original shape once you go slower.
On mine, the dimples stayed, so I reinstalled the original hood lock and just keep the hood pins for looks.


CAUTION, after reading this post.
The twist locks are for looks only you MUST have a regular hood latch / catch system.
  Reply
#9
OMS;20404 Wrote:[quote=luxstang;20382]
Although this is not related to the prep work or how to resolve the problem, I just wanted to give my two cents on the subject about fastening the lock too tight.
Even if you adjust them so that they don't put any pressure on the hood, it will dimple as soon as you go fast on the freeway as the wind will try to push the hood open thus pushing it up against the locks or pins.
I had that problem with mine.
Usually the metal is flexible enough absorb this and will go back to it's original shape once you go slower.
On mine, the dimples stayed, so I reinstalled the original hood lock and just keep the hood pins for looks.


CAUTION, after reading this post.
The twist locks are for looks only you MUST have a regular hood latch / catch system.


I remembered after I posted this that I don't have the original style hood locks. I added the 60something Shelby style hood pins that are perfectly able to hold down the hood. Maybe that's why mine had dimples, as the base of these is much smaller so the pressure is not as widely spread as with the twist locks.
I have never seen twist locks in real life, so I don't know if they are only for looks. Blush
Anyway, better to have the hood latch in place, I guess.

[Image: 1z21rv4.png]

Mike

"If I were you...... I´d rather be me."  Tongue

Check out my video:
http://www.7173mustangs.com/thread-my-mustang-in-action

  Reply
#10
OMS;20404 Wrote:[quote=luxstang;20382]
Although this is not related to the prep work or how to resolve the problem, I just wanted to give my two cents on the subject about fastening the lock too tight.
Even if you adjust them so that they don't put any pressure on the hood, it will dimple as soon as you go fast on the freeway as the wind will try to push the hood open thus pushing it up against the locks or pins.
I had that problem with mine.
Usually the metal is flexible enough absorb this and will go back to it's original shape once you go slower.
On mine, the dimples stayed, so I reinstalled the original hood lock and just keep the hood pins for looks.


CAUTION, after reading this post.
The twist locks are for looks only you MUST have a regular hood latch / catch system.

Hi OSM,

I have a regular hood latch / catch in place
  Reply
Share Thread:  


Possibly Related Threads...
Thread Author Replies Views Last Post
runninpony Carpenter Hood to Cowl Seal NOT A T5 6 308 05-27-2018, 08:03 AM
Last Post: NOT A T5
  Hood lock install Jeff73Mach1 37 8,004 04-25-2018, 03:22 PM
Last Post: Jeff73Mach1
  Hood Options? 71_resurrection 28 2,010 03-23-2018, 09:34 PM
Last Post: keiths71
  Another Hood Lock Question Copestang 2 424 01-11-2018, 09:01 AM
Last Post: timachone
  Cleaning product for black portion of hood Mike1972Mustang 9 1,002 12-02-2017, 06:33 PM
Last Post: red351
  What color to paint hood Copestang 4 600 10-29-2017, 11:51 AM
Last Post: Copestang
  Honeycomb grille between windshield and hood Pegleg 13 986 07-12-2017, 02:33 AM
Last Post: Pegleg
  the hunt for fasteners 87fox72mach 6 458 02-19-2017, 05:21 PM
Last Post: sdstang



Users browsing this thread: 1 Guest(s)