bondo, the crap you just can,t avoid using at times

grumpyvette

grumpyvette

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Ok if you own a car long enough youll eventually get a few minor dents or scratches and most guys will prefer to do minor repairs yourself if it saves a good deal of cash.
read the linked instructions below for detailed info
I had my first fast car, a 1965 Pontiac tempest with a BIG BLOCK Chevy and a MUNCIE 4 speed when I was about 18 if I remember correctly, the car was almost new but the previous owner had blown the pontiac v8 engine running it without coolant so I got it very reasonably,I temporarily repaired it, until I had time, then, I promptly installed and modified several different engines, in the car over the next several years.
anyway, the car came with minor dents I wanted repaired, I ask around and one of my mentors showed me how to do the repair, the short version, is you use a dolly and hammer to smooth out what is excessiable from both sides and a slide hammer on panels that can,t be accessed from the inside, the idea is to get the metal surface back to as close as you can to its original location, once everything's within 1/16-1/8" or so from its intended location you sand the surface with something like 80 grit sand paper wrapped around a sanding block until you've removed old paint and basically smoothed the surface but left it covered with micro scratches, you clean and dry the surface several times, then use a flexible applicator to try to smooth the peanut butter like bondo over the minor surface blemishes after mixing the two components that form the bondo,( per instructions) you need to be fast, because temp and the amount of hardener used effect the bondo consistency. after about 3-6 minutes it starts to get stiffer (QUIT ! WAIT! for it to harden, that can take 30 more minutes until its easily sanded, once it is, you sand and repeat the bondo application until and as often as necessary to get the surface correct, each time use a bit finner sand paper (WET DRY) and a running water hose is good once you get things really close and reach about a 300 grit, you try to get about a 600 grit finish before even thinking about primer paint, but once your almost perfect and glass smooth the primer paint gets used as it helps spot imperfections. it needs to look perfect with a lightly sanded primer over the bondo , and with no more than about a 1/10th inch thick bondo for the job to work out correctly

thats the basics, but read the links for far more exact info

theres quality bondo type fillers like this
http://www.autobodytoolmart.com/marson- ... 10295.aspx

and theres the cheap crap you get at chain stores and walmart


http://www.ehow.com/how_2149826_body-fi ... epair.html

http://autorepair.about.com/b/2008/02/1 ... ad-out.htm

http://autorepair.about.com/od/fixityou ... /bondo.htm

http://www.wonderhowto.com/how-to/video ... ir-267153/

http://www.youtube.com/watch?v=db3PQQvm7cQ

http://www.ehow.com/how_112958_repair-minor-dents.html
 
the SMC (SHEET MOLD COMPOUND) on corvettes makes the use of the correct adhesive filler a big plus over use of bondo, but as always proper surface prep and READING THRU AND following the directions helps a great deal
generally having a scratch ground down and a rough surface texture helps
http://books.google.com/books?id=pQAAAA ... q=&f=false

http://www.lordfulfillment.com/upload/UI3003.pdf

http://www.azautobodysupply.com/10fuezplbore.html

http://www.tcpglobal.com/autobodydepot/fusor.aspx

http://www.sjdiscounttools.com/fib880.html
 
Last edited by a moderator:
BTW NEVER EVER USE STANDARD BONDO ON A CORVETTE!
I was over at one of JACKS friends shops today where he was about to try and make a repair on a rather nasty crack in the rear of a 1968 corvette that he had acquired by backing up into a sign post he failed to see in a parking lot.
I told him the product he had on hand was never meant to be used on a corvette and would result over time in a problem with the repair or paint,
(experience is a strict teacher) so I was trying to prevent him from making mistakes ID made decades ago!
theres special products designed to BOND and FLEX slightly for use on a corvette, many corvettes are NOT FIBERGLASS
but a slightly different product The Corvette began production in 1953. The body panels are made from fiberglass at that time but changes in manufacturing and improvements caused changes and resin using two basic components injected thru glass mat and production methods and continuously have improved to make production faster ,less messy and less expensive over the years. These current methods are referred to as Press Molded Panels and Sheet Molded Composites or SMC.

THIS STUFFS GREAT FOR FIXING MINOR PAINT CHIPS, or similar cosmetic damage that goes deeper than the paint alone but its not good for structural repairs in the body panels
http://www.uschem.com/products/docs/TDS_Icing2.pdf
CHECK WITH A GOOD COMMERCIAL BODY SHOP SUPPLY STORE ON WHATS REQUIRED FOR YOUR YEAR CORVETTE, and CHECK WITH A LOCAL PAINT SUPPLY FOR PAINT, as the vast MAJORITY of the SUB STANDARD PRODUCTS sold cheaply at auto parts stores are NOT DESIGNED to be used on a CORVETTE

http://www.marinetex.com/

http://www.glassmandan.com/tutorials/002.html
Corvette Fiberglass Body Repairs:

There are different generations of fiberglass used on the Corvettes throughout the years. The 1953 Corvette, being the first, had the most unusual fiberglass. This was hand laid fiberglass using fiberglass cloth. Fiberglass cloth has the uniform weave, looking much like a screen door. If it is used today you will have what is called telegraphing. This basically means the checker appearance will be visible is the final paint. This is the reason why it is necessary to use fiberglass mat. It is not uniform, but is disorganized, with the strands running at random. This type of glass will not telegraph through the paint.

For the previous statement to be true there must be enough primer covering the fiberglass. It is best to gel coat the finished fiberglass repairs. Usually this would include the entire body. The body parts, doors, hood, deck lid, and trunk lid would be optional as deemed necessary. 1953 - 1957 Corvettes are the most likely candidates for gel coating. 1953 and 1954 we can call first generation fiberglass.

Sometime around the middle of 1954 gel coating ceased. The hood, deck lid, trunk lid and sometimes the doors would be in the 2nd generation fiberglass. These parts were press molded (smooth both sides). In 1955, the entire Corvette was done in press mold type fiberglass. We will call this the 2nd generation fiberglass.

1958 Corvettes through the 1962 Corvettes would be the third generation fiberglass. This is a better type of fiberglass. The methods were better. Around the hood opening there would be even hundreds of cracks in the 1957 Corvette, likewise all the openings for the doors, trunk, etc. The 1958 Corvettes through the 1962 Corvettes didn't have this problem. This makes the repairs easier and less costly. Other higher qualities would show up as you work on the 1958 to the 1962 Corvette. The 1963 to 1967 Corvettes are even better yet. Other than repairing a wreck, there are usually only a few cracks at the corner openings of the windows, hood, headlights, etc.

I do a resurfacing to the 1953 - 1957 Corvettes. I call this method, "reskin", which is to cover the body with a layer of fiberglass. After all the repairs have been completed, I use a 3" rubber pad with a 24 grit sanding disc and an electric drill. I slowly rough the area to be reskinned. 1953 and 1954 Corvettes usually need the entire body done. 1955-1957 Corvettes, maybe just the body only, not the body parts.

Reskinning a Corvette is a long slow process. Grind the entire body with 24 grit to really scuff the surface. Use fiberglass mat, not cloth. Apply one layer of 1 1/2 oz fiberglass. This type of fiberglass is the general thickness you will buy from most stores. Use a roller designed to roll fiberglass. This will roll out the bubbles and bring the resin to the surface. The strength is in the fiberglass. The resin is the bonding material. The resin does not have the strength. It is necessary to have total saturation of the fiberglass. You will know you have total saturation when the fiberglass turns totally clear. The type of resin to use is laminating resin. Do not use casting resin. Casting resin has wax in it. Resin too thick will be hard to saturate the fiberglass. Resin too thin will run off onto the floor. If the resin drains out of the fiberglass, the glass must be removed and the process done again. Allow the reskinned areas to cure at least 24 hours.

Now that the fiberglass work has had time to cure, you must grind the glaze off top of it. Grinding the glaze insures adhesion. Now spread a thin layer of bondo over the areas of work. Sand the areas until a good contour is accomplished. Never use bondo too thick--1/8" at the very most in a bad area, or else you must use fiberglass to repair it. Use 80 grit sand paper or coarser when sanding the bondo. Eckler makes the best bondo for the job. The final step is to gel coat the Corvette. 1953 to 1957 usually needs the entire body gel coated. 1958 to 1962 Corvettes may be gel coated where necessary. Again, Eckler makes the best gel coat for the job. During the restoration of the Corvette body, the more sun the better. As much curing in the sun as possible is best. Let's say your Corvette has been painted, assembled and ready for show, if it never leaves the garage this is okay. On your first three-day car show in the hot sun, you will see if your efforts survive.

The main key to making sure your paint job survives is to always work clean. Clean hands and clean rags all the time. I cannot stress this enough. I never have bubbles appear in my paint jobs because of my constant efforts to remain clean.


LINKS YOU SHOULD READ THRU
viewtopic.php?f=61&t=6966&p=24194&hilit=paint+corvette#p24194

viewtopic.php?f=61&t=7075&p=23525&hilit=paint+corvette#p23525

http://www.corvette-restoration.com/res ... _Paper.pdf

http://www.corvettefever.com/techarticl ... ewall.html

http://www.ehow.com/how_5898776_repair- ... glass.html

http://www.bodyshopbusiness.com/Article ... ettes.aspx

http://www.vetteweb.com/tech/vemp_0811_ ... ewall.html
 
what brand and type of bondo do you guys find produces the best results , and what brands always seem to fail to adhere well ,long term, collect moisture and smooth or fail to smooth evenly, sand well, and generally produce the best results in your opinion?
yes I.m all too well aware that the ratio of base to hardener the condition of the surface its being used on, and how well its mixed,before its used, how thick its applied, and the temperature and humidity effect the results and all types have a limited "WORKING TIME"
but after using several brands I do see marked differences and would like YOUR feed back?
 
I've been using Evercoat Z grip for a few years. Trying a gallon of 3M Platinum now.
 
They are all good high quality fillers evercoat brand in general makes a good product I always order online but sure a autobody supply company might carry it local.
 
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