Vehicle Outer Door Panel Vibration!

Stck a suitable sheet of damping material on the inside.
Increase it's curvature, or add a crease/style line along the panel.
Next!
Del

There is a styling line present but it gradually diminishes,which reduces the sections modulus.Also a curvature is present. i cant play with all these possibilities-except applying damping material!

can u suggest some damping material?

A quick Google came up with this ...

http://www.crutchfield.com/p_1541015536/Original-Dynamat-10155.html?tp=2277&tab=detailed_info

Regards Woody.

I've used similar stuff to Woody's suggestion - Anti Vibe sound deadening material - also available from Halfords in the UK.

It's very effective for quietening lab machinery, when applied on the inside faces of sheet metal panels. Probably works for cars as well .

Lead sheet, but don't lick it ...
Dunno really there must be special materials manufactured for this purpose...high desity rubber foam..fill the door with expanded polyuratane foam? Oh you want to open the windows!
Del

Is this on a 'tin lizzie' - wood frame door- or a modern vehicle?

Modern vehicles sometimes have a damping strut from the window channel/guide out to the outer skin to achieve damping. Has this rusted off? Maybe an idea to install one, with some suitable material over the edge of the strut where it meets the skin, like a piano string damper.

Notwithstanding, all the other replies are good/excellent.

Cheers,

Stu.

door panel vibrations while closing the door. That would put the resonant freq of the panel at about 1 Hz.

This sounds like the car is at rest, not moving. In which case, adding mass to the panel won't help.

I need clarification.

Yes the car is at rest!

when i close my door,the outer door panel vibrates/deflects!

the deflection/vibration is observed in the middle of the door panel.

this is basically due to a smaller section modulus of the panel sheet metal.

the thing is i cant modify the sheet panel thickness(0.8mm). to reduce the deflection in panel i need to add some reinforcement or antidrumming material!

I'm assuming that you are going to dismount the interior trim panel to access the outer door panel.

Select a location in the middle of the area of deflection, then make a template of the profile of the area from top to bottom. Duplicate this profile with a piece of flat, thin metal stock 5x the door panel thickness, 50% of the height of the area and 15% of the width of the area. Modify these dimensions as your intuition dictates. Or, you could probably get the profile close enough by using the outside of the panel as a gauge, and bending by hand. Bond in place with a flexible adhesive, on the inside, of course.

This should stiffen it up nicely.

And, don't slam it.

In the old days (1950's) the answer to this problem was to spray the inside of the door panel with undercoating (adds mass and dampening). We often saw cars with this coating obviously applied at the factory since there would be overspray body paint on it. You can still buy undercoting in spray cans. Might be a big job getting the insice upholstery panels off what with special tools needed and keeping all the electrical connections in order.

Ed Weldon

can u tell me on which cars did you see such kind of undercoat? just for referance purpose

Underseal was common on many if not most cars sold in the UK during the '50s & '60s (can't speak for other parts of the world).

Mig Weld four 3' sections of 2" channel to the door from hinge to striker plate and wrap a minimum of 10 layers of Tyvek on the exterior of the newly supported door and follow up with a drum of Bondo mixed with MEK. Re-paint the car coral pink and turtle tan, then park it somewhere you never have to look at it again

Or, If this is your car...

Coat the inside of the door with a thick undercoating or adhesive and glue to it maybe three strips of 1/8" x 1" x 18" strips of fairly stiff 1/2" aluminum angle or stiff plastic, spaced evenly apart. [Make certain the aluminum and/or plastic clears the window before you glue it in!]

If the door continues to vibrate, check the striker plate and rubber seal... Or maybe do that first then go after the project (above) requiring you to remove the door panel and manipulate the thick adhesive and such.

JL Mealer
Mealer Companies LLC
America's Next Major Automaker
http://mealercompanies.com

Close door slowly and carefully.

What is causing the door skin to vibrate?

Is the hinges binding, and need lubrication to swing smoothly, there must be something that is causing the skin to make a noise.

You could try painting the inside of the skin with sound deadening paint/material, same as whats sprayed on the underside of car floor pans... or inside speaker enclosures.

Try http://www.quietsolution.com/html/quietcar.html I used three coats on my fiber glass Lotus coupe in the interior, doors and in the trunk and reduce the sound by 20DB. Hope that helped

Use a pall pein hammer to dimple the door surface, that should stop the vibration and may even iprove the aerodynamics...start a new trend...dimpledoors we call 'em.
Available from KrisDel^TM enterprizes
Del

Why didn't I think of that? Works on golf balls. Eh?

Stu.

Hmmmm ...

Well i tried reinforcing my door with the help of reinforcement pads by "Paracot".

they have to under go heattreatment @ 160deg. they didnt work out. i think i will have to strengthen my panel during forming process!

thanks a lot for your guidance!