YC,I used both the 3M Rubberized undercoating and a similar product made by Duplicolor ( 3m stuff out of stock) and the results were great for both products.
Paul

 

Ditto. Very easy to touch up too.

 

What do you guys recommend to put in the tire/wheel wells / onto the AL panels to stop the annoying stone dinging while driving?

Ihave seen lizard skin, etc., but that's all pretty expensive.

What about the "out of the can" 3M Rubberized Undercoating?

Any other recommended products?

Maybe something that could also be used on the underside of the body?
Thanks.

"Herculiner" used by many many people here on the forum. Can be purchased at your local AutoZone. I used it and I'm very happy with it. The large box includes enough to coat the entire underneath side twice, plus three or four coats for the wheel wells.. Less than $100 and it includes the rollers and paint tray.

Joe - -

 

I used the dupilcolor spray on stuff works great. I have also used herculiner and it was good also.

 

I used the Herculiner kit I got from Wally World. $45.00 and I had almost 1/2 gallon left. The kit came with a brush,roller and tray. That stuff is nasty to get off places you don't want it when it dries.

 

I have been using the left over Duplicolor truck bed linner.
Tim

 

I'm with Big E on this. I didi mine a couple of weeks ago ant ti really quieted the car down. Very happy witht he results. Messy job, though. Do what you can before body install. Would make life much easier later.

Steve

 

howbout wheel well liners from alex,nice product!!

 

They cover very well and do a great job protecting from rocks. I used the Herculiner product and got two coats on the entire car and 4-coats in the wheel wells. It sealed the raw fibreglass and will help against star cracks.

Do this before paint, just in case you have a thin spot and stay an inch or so away from any edges (wheel well, nose, vents etc.)

Ray

 

I used the Dupli Color undercoat. Sprayed about 4 coats, letting it dry for about 30 minutes between coats. It's on pretty thick and does a good job of quieting road noise. I was thinking about the wheel well liners, but from what I could see, they don't cover the underside of the fiberglass, and won't protect against star cracks in the finish from rocks being thrown up by the tires. Be sure and mask off anything that you don't want undercoat on, and wear old clothes

 

Do you do this before the body work?

 

Steven,
It is best to, that way if you get any on the outside you can still get it off without damaging any finished surfaces.

 

Is it OK to use the 3M or Herculiner on the underside of the wheel wells after the car has been painted ? Someone told me it may bleed through the fiberglass and affect the paint job.

 

I coated the wheel wells after paint. The painter applied some to the inside of the body,I think he did it prior to paint, but I wanted more in the wheel wells. Mask off what you don't want undercoated and go for it.

 

Good Info

Sounds like I might have Jeff (Whitby) put the coating in on the body (because it is there already) and I will go with some ruibberized coating for the AL panels.

Just trying to figure out what brand?!

 

To protect the paint from star patterns, rubberized undercoating will work but you will need about 4 cans (no joke) per wheel well.
Here is what we did to protect the wheel wells in my buddys roadster:

Here is a shot with Damplifier Pro getting applied:

Here is a full layer of Damplifier Pro in the wheel well:

 

We did this to all 4 wheel wells. In total we use up about 3 or 4 sq feet each.

Next was the Spectrum.
First, we had to protect the car from the coating. For this we use the few garbage bags around the brakes, and a roll of sell adhesive carpet plastic.
This stuff is awesome for masking off areas of the car you want to protect from overspray.

 

Once we masked everything off, it was time to spray the Spectrum vibration coating in the wheel wells on top of the Damplifier Pro:

This is a shot of Spectrum after a single coat.

Spectrum is a very thick vibration paint and is set to a specific viscosity, so that it can be applied at 20 mils (20/1000th inch) in each coat. Apply it any thicker than 20 mils (about 1/2 mm) and it will either start to run or drip.

So after we did a nice solid layer on each wheel well, we would simply move on to the next one. By the time we finished our first coat on the 4th wheel well, the first one had already begun to skin over, which means we can add a second layer.

The product starts out dark blue/grey in color, but once it dries it becomes black. SImilar to a 2 part polyurea bed liner. But unlike a bed liner, this product weighs a lot less and will provide noise damping results that can only be attained with 8 layers of bedliner.
Bed liners are great for protection, but terrible for vibration damping. If you need proof of that, tap on the bed of a truck with a hammer and see how much vibration and resonance is still there. On the flip side, I would never suggest using Spectrum in place of a bed liner in a truck bed. This stuff is not nearly as strong as a bed liner for heavy duty abuse. It will stand up to the elements under a car however and will kill a ton of noise while doing it!

Spectrum will start to darken after about 20 - 30 minutes depending on the temperature which is when additional layers can get applied.

Many people will use Spectrum as an interior coating and exterior coating. If we were going to do this, the roadster would need about 5 gallons:
2 gallon as an undercoating
2 gallons in the cockpit
1 gallon in the trunk


We only used Spectrum in the wheel wells however and ended up applying just a little more than 1 Liter (1/4 gallon) per wheel well.


Another shot of a wheel well coated:

This is a shot of Spectrum after it has had about 15 minutes to skin over.
You can see how it is turning black already. Another 15 minutes and it will be good!

In 24 hours, the Spectrum will be pretty firm to the touch.
In 72 hours it will be 80% cured.
It takes 30 full days to cure, at which point you will notice 100% of the sound deadening results.

 

Take note they covered the floor too. Don't ask how I know you need to cover the floor as well.

 

so herculiner or bed liner for under body and 3m type rubberized coating for under alum panels. Is this right or are they the same thing and can be used in either area????????

 

Could this be used instead?

http://acroadsterinteriors.com/Fenderliners.html

 

Those look nice, too bad don't make a product to cover the whole bottom exterior/ giant skidpad....

 

Truck liner

I am using truck liner in the wheel wells and on the underbody.
If it is good for a truck bed that gets torn up by engine blocks etc. then it should be good for the underside of the Roadster I thought.

 

I used the 3M spray can product in my wheel wheels and after less than 1000 miles it is almost entirely removed from the aluminum areas. This summer I plan to try something else.
Doug

 

A little help here clarifying. For the fiberglass body use a bed liner like herculiner etc?? ANy for under car alum (footbox, floor) Use rubberized?? sound like 3m might not be good??? Or do you the same product on both fiberglass and alum panels etc.

 

when spraying on the aluminum surface....it must be roughed up and cleaned or the undercoat will not stick.(long term)
Dave

 

Truck Liner

Is is ok to use the herculiner on the under side of the hood?

 

Is is ok to use the herculiner on the under side of the hood?

It wouldn't hurt anything to use it under the hood but it might not be too nice to look at.