Hood separation

[Scottjeffrey]

Has anyone encountered their hood separating from the bars that run front to back? Ever bonded them back together with some 3M product or the likes?

Thank you for you r help,

Scott

Edited March 21, 2019 by Scottjeffrey

[harold]

I used this stuff: 3M Automix Flexible Foam - 08463.  It is designed for this application.  Unfortunately it requires a special applicator gun, kind of a caulking gun.   You mask off both sides of the gaps, inject the foam, and after cure, carefully trim the foam that expanded out. 

 

Oh- but first make sure that you hood isn't bowed down in the center due to things like people sitting on it, or being piled high with boxes while stored in a corner of your garage.  Work out the deflection first before foaming.  Mine was amazingly off.  I was able to get it back to its original shape. 

 

H

[Scottjeffrey]

4 minutes ago, harold said:

I used this stuff: 3M Automix Flexible Foam - 08463.  It is designed for this application.  Unfortunately it requires a special applicator gun, kind of a caulking gun.   You mask off both sides of the gaps, inject the foam, and after cure, carefully trim the foam that expanded out. 

 

Oh- but first make sure that you hood isn't bowed down in the center due to things like people sitting on it, or being piled high with boxes while stored in a corner of your garage.  Work out the deflection first before foaming.  Mine was amazingly off.  I was able to get it back to its original shape. 

 

H

Thank you so much, Harold!

[Scottjeffrey]

48 minutes ago, harold said:

I used this stuff: 3M Automix Flexible Foam - 08463.  It is designed for this application.  Unfortunately it requires a special applicator gun, kind of a caulking gun.   You mask off both sides of the gaps, inject the foam, and after cure, carefully trim the foam that expanded out. 

 

Oh- but first make sure that you hood isn't bowed down in the center due to things like people sitting on it, or being piled high with boxes while stored in a corner of your garage.  Work out the deflection first before foaming.  Mine was amazingly off.  I was able to get it back to its original shape. 

 

H

Harold; Am I correct that the hood sits a distance off the 'bars' and that the foam maintains the separation? Do you inject it through the hole in the 'support bar' or from the sides?

[JAS]

The driver's side on mine has separated. Spoke with an autobody pro about it. Not sure about the 3M Automix Flexible Foam Harold mentioned, but the autobody guy warned me that applying an adhesive might "suck" the skin down too far if the hood's frame wasn't perfect. As my hood's frame is slightly out of wack, I chose to leave it as is. I can see it vibrate a bit as I drive but I can live with it.

 

Will have to read up on that 3M stuff though...perhaps it doesn't shrink when cured.

 

J

[Scottjeffrey]

8 minutes ago, JAS said:

The driver's side on mine has separated. Spoke with an autobody pro about it. Not sure about the 3M Automix Flexible Foam Harold mentioned, but the autobody guy warned me that applying an adhesive might "suck" the skin down too far if the hood's frame wasn't perfect. As my hood's frame is slightly out of wack, I chose to leave it as is. I can see it vibrate a bit as I drive but I can live with it.

 

Will have to read up on that 3M stuff though...perhaps it doesn't shrink when cured.

 

J

Hi Jay, Its says it does not shrink.   

 

[JAS]

That sounds encouraging! Would be nice to lose the vibrating hood :-) 

[harold]

I injected it along the gaps, so it looks like the original stuff that was in there.    There was a post about 2-3 years ago where someone showed in great detail, with lots of pictures, how he did it for his trunk lid.  I found that very helpful.    Let me see if I can find that with search...

[harold]

Found it;  a diffierent brand product, but the same idea.  
Hood Sheet Metal Separated From Support

[Scottjeffrey]

 

5 minutes ago, harold said:

Found it;  a diffierent brand product, but the same idea.  
Hood Sheet Metal Separated From Support

Thank you Hal!

 

[tedwardcairns]

After doing some reading from a combo of a bunch of different threads I just need clarification on a few things regarding the hood support.

For this par that runs across should I be using the panel bond from 3M (08115) or the expanding flexible urethane foam from SEM?

 

For this section same question, expanding foam or the panel bonding?

Final question about the main supports down the center, should they be flush against the sheet metal or have a gap between for the foam to go into?

The hood was dipped so there isn't any of the original stuff left for reference.

 

Thanks in advance 

[Scottjeffrey]

1 hour ago, tedwardcairns said:

After doing some reading from a combo of a bunch of different threads I just need clarification on a few things regarding the hood support.

For this par that runs across should I be using the panel bond from 3M (08115) or the expanding flexible urethane foam from SEM?

 

For this section same question, expanding foam or the panel bonding?

Final question about the main supports down the center, should they be flush against the sheet metal or have a gap between for the foam to go into?

The hood was dipped so there isn't any of the original stuff left for reference.

 

Thanks in advance 

I went with the SEM product. I was impressed with it.  SEM 39357 Flexible Urethane Foam - 7 oz.

As to the hood being flush to the supports, I suggest the answer to be no.

Good Luck,

Scott

[TobyB]

flexible foam-

anything rigid runs the risk of marking through the skin

and showing up in the paintwork later, especially

if the hood gets pushed on.

 

t

 

[tedwardcairns]

On 10/13/2023 at 4:21 PM, Scottjeffrey said:

I went with the SEM product. I was impressed with it.  SEM 39357 Flexible Urethane Foam - 7 oz.

As to the hood being flush to the supports, I suggest the answer to be no.

Good Luck,

Scott

 

I've used the SEM 39357 on the trunk supports already as laid out in the "Restoration one panel at a time" thread. Worked out great.

 

10 hours ago, TobyB said:

flexible foam-

anything rigid runs the risk of marking through the skin

and showing up in the paintwork later, especially

if the hood gets pushed on.

 

t

 

 

I'll be sure to only use that SEM product then! I'd hate for the paint to have defects later on down the road from the use of the wrong stuff.

Thanks again for the advice! 

[Lucky 7]

Mine were separated and the support ribs both had stress fractures on either side of that big hole. I welded the fractures and ran seam sealer on both sides of the ribs to stiffen up the hood skin. It’s a relatively rigid connection, which goes against above advice, but it’s worked well for me. Paint is fine and I’ve noticed a large reduction in the flex of the hood when I open it. The whole enterprise feels much more solid.