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Re: Newbie post - Marketwatch, paint and filler thickness

Posted: Sun Dec 04, 2016 4:08 pm
by C J Murray
Welcome Brad. Give us some details about your 356, how much filler, where, background history of the car, your personal philosophy when you chose your car? There is no wrong answer but since you used the meter to evaluate your purchase it would be interesting to hear what you found.

Re: Newbie post - Marketwatch, paint and filler thickness

Posted: Wed Dec 07, 2016 1:07 am
by Dave Erickson
Greg Bryan wrote:Here are pictures I took at Wilhoits at last March's open house. Certainly there are other doing this level restoration, but i have these pics ...
Greg, thanks for sharing those. To my uneducated eye, it looks like a lot of that coupe has lead on it. Is that typical of a bare metal restoration? I kind of like the look.

Re: Newbie post - Marketwatch, paint and filler thickness

Posted: Wed Dec 07, 2016 11:13 am
by Greg Bryan
Dave - I think this is very indicative of a new car - Porsche achieved those fabulous gaps by building the edges with lead and hand filing to get the perfect fit. If you haven't seen the "Made by Hand" film from the early 1960s, look it up on YouTube - it's fascinating ...

Re: Newbie post - Marketwatch, paint and filler thickness

Posted: Wed Dec 07, 2016 4:05 pm
by Hugo Sheers
David Green wrote:Hi Steven,
I borrow a friend's Delfesko paint meter that cost him about $500. it comes with calibration strips and its accuracy appears consistent when tested on new car paint. Their website, link below, contains much information but there are at least two types: those for ferrous metals and others for nonferrous, aluminum and plastic that I believe use ultrasound. With it I was able to confirm that there was no original paint under my incorrect color repainted, but otherwise very original, 1953 coupe.
Regards,
David

http://www.defelsko.com/products/coatin ... -gages.htm
David,

Interesting, how were you able to determine that there was no original paint under the re-spray using a paint meter?

Many thanks
Hugo

Re: Newbie post - Marketwatch, paint and filler thickness

Posted: Fri Dec 09, 2016 8:05 pm
by John Willhoit
40 mils is .040" which is about the thickness of a dime (not very thick). Most original 356s had a good coat of primer that was block sanded before the synthetic enamel was applied and baked on. They will measure around 7-10 mils depending on how much they've been polished.

A typical modern base coat (water base) and acrylic urethane clear coat finish will measure from 12-15 mils, and that's the minimum.

Blocking primer is typically 10 to 20 mil thick once it's been blocked down properly over a straight metal panel like a door. Other areas can be slightly thinner or slightly thicker depending on the painter and/or the condition of the metal. Small imperfections and low areas can be built up using a fill putty and this is rarely more than 10-20 mils.

The cars we do are block sanded to be perfectly straight when you look down the side of the car (like a mirror). Most of our cars will measure between 20 and 35 mils on all panels, and we use zero bondo. Keep in mind that paint meters only read to 35-40 mils.

In my opinion, paint meters are good for determining the thickness of original paint, or to identify a repainted panel on a newer car. They are generally worthless on a vintage Porsche that has been repainted. A solid magnet can sometimes be used on a 356 to identify a thick application of bondo (1/4") but this would only be for someone who has no idea about bodywork or painting. A good bodyman or painter can spot poor quality work without the use of measuring tools.

I have seen cars that were deemed to be excellent with "little bondo" by car purchasing consultants that had serious body issues relating to replaced panels, accident damage, and bad body lines. If you're going to look at a car, take a real body/paint expert with you to evaluate the car. You wouldn't have your "purchasing consultant" check the engine if he wasn't a mechanic, don't have him check the body if he isn't qualified.

Re: Newbie post - Marketwatch, paint and filler thickness

Posted: Fri Dec 09, 2016 10:31 pm
by Mike Wilson
Thanks, John. Great info.

Re: Newbie post - Marketwatch, paint and filler thickness

Posted: Fri Dec 09, 2016 10:59 pm
by Dan Epperly
Mike Wilson wrote:Thanks, John. Great info.

He may have just put Prescott K out of business. :D

Re: Newbie post - Marketwatch, paint and filler thickness

Posted: Sat Dec 10, 2016 8:27 am
by C J Murray
Dan Epperly wrote:
Mike Wilson wrote:Thanks, John. Great info.

He may have just put Preston K out of business. :D
I'm not surprised to hear that the meters aren't accurate since I have heard this before but Prescott is correct to point out the cars that were slapped together vs the ones that were skillfully restored. He is doing us a great service by differentiating between the quality of the cars he reports about. It may not interest some but it has a large bearing on value. He is not out of business.

Re: Newbie post - Marketwatch, paint and filler thickness

Posted: Sun Jan 08, 2017 12:17 pm
by Doug McDonnell
Thank you John for your detailed answer on how your shop restores our Beauties. And for including the paint thickness values you end up with.

Re: Newbie post - Marketwatch, paint and filler thickness

Posted: Sat Apr 01, 2017 12:09 pm
by Steven Murray
Four month's later and I did just pick up the ETG mini Iron/Ferrous for reasonable $240 ish and will start playing with it. Some it the documents say the mini is only good up to 10 mils so 40 mils of the ETG-A would be better since mr. kelly finds cars with 80 mil of bondo. Once it stops raining i'll try it out on my 7 cars.

Does seem to do 40 mils after all

Posted: Mon Apr 03, 2017 2:15 pm
by Steven Murray
I was trying the ETG mini on my 7 cars and did get readings in the 30s at times. It does seem to do up to 40mils. Super!

Re: Newbie post - Marketwatch, paint and filler thickness

Posted: Mon Apr 03, 2017 2:21 pm
by Doug McDonnell
From John Willhoits values above that sounds very good.

Re: Newbie post - Marketwatch, paint and filler thickness

Posted: Tue Aug 08, 2017 1:49 pm
by Alex Finigan
If you don't have access to a meter, or don't have it with you at all times, it's pretty easy to spot a bondo bucket once you've looked at a lot of these cars.
As mentioned here, fat door edges, and the trailing seam of the front fender are a dead giveaway, they should be very thin.
You should be able to tap on any panel with your fingernail, and it should sound like tapping on an empty coffee can.
My '59 Coupe is like that, and it's very distinctive.
A car with a lot of bondo has a very dead sound, and the weight of the doors, and hood are dramatically different.

Re: Newbie post - Marketwatch, paint and filler thickness

Posted: Tue Feb 06, 2018 7:44 pm
by David Aronson
I am looking for a paint/body shop, as my guy, after having my car for 2 years, had a stroke. He was an anti-lead type who was planning to use plastics. All the shops that I have visited in N. Cal. fill with polyester fillers. They are deathly afraid of the lead "degassing" and ruining their paint.
I am wondering, is this a problem. They melt out the lead and fill the contours with filler. Didn't the lead degas enough during the 50-60 years that it sat. I am not an anti-lead fanatic and I do not have an anti-plastic filler mentality either. I would just like a scientific reason why lead is out for so many shops. One has suggested that the filler takes less technique. An artistic medium gone the way of Venetian plaster. Oh wait, I just paid a fellow to "venetian plaster" my walls at home. Not a good parallel. Aside from this being California, with an overprotective policy towards anything that requires heat, gives off a vapor or could in some way be harmful if swallowed. And, does it matter to the judge, if the lead is gone and a polyester takes it's place.....

Re: Newbie post - Marketwatch, paint and filler thickness

Posted: Tue Feb 06, 2018 8:33 pm
by Dan Epperly
David Aronson wrote:I am looking for a paint/body shop, as my guy, after having my car for 2 years, had a stroke. He was an anti-lead type who was planning to use plastics. All the shops that I have visited in N. Cal. fill with polyester fillers. They are deathly afraid of the lead "degassing" and ruining their paint.
I am wondering, is this a problem. They melt out the lead and fill the contours with filler. Didn't the lead degas enough during the 50-60 years that it sat. I am not an anti-lead fanatic and I do not have an anti-plastic filler mentality either. I would just like a scientific reason why lead is out for so many shops. One has suggested that the filler takes less technique. An artistic medium gone the way of Venetian plaster. Oh wait, I just paid a fellow to "venetian plaster" my walls at home. Not a good parallel. Aside from this being California, with an overprotective policy towards anything that requires heat, gives off a vapor or could in some way be harmful if swallowed. And, does it matter to the judge, if the lead is gone and a polyester takes it's place.....

Lead is insanely poisonous, you don't have to eat it like a preschooler. Anymore it's dealt with by guys wearing full hazmat suits.