PierreOlivier

What is the secret to getting straight front fender peaks? I am having to literally rebuild them using VPA.

DUB

SECRET: Proper prep BEFORE applying of the VPA, time, patience, proper sanding techniques, a 'sharp eye' to see them...and a very good sense of 'feel'.

I build them all the time and sharpen them up to give the Corvette a cleaner look.

You definitely need to use a rigid sanding board...and then it is literally sculpting them. It is hard to tell someone how to sand them...much like me trying to tell you how to sing.


You have two geometric planes that come together and make a point....thus you have to stay on each geometric plane and get it right them do the other geometric plane...and where they come together will be a line so sharp...if done correctly...it can cut paper with very little effort.

DUB

929nitro

I have to rebuild mine as well and understand what you are saying. Once you finish sanding the two surfaces how sharp do you leave the resulting corner and any tips for how to relieve it if they are not to be left sharp?

DUB

I like the lines really sharp....because I am often times applying gelcoat on NON-SMC Corvettes,,,so that in itself will round off the edge a bit....then when I block sand eh gelcoat...I can either sharpen them back up or leave them and when i apply my other primer and paint...the edge is rounded off and just gives it a more defined look. I am not worried about anything original...because my paint work is clearly NOT factory...so why stop there.

You can take some 180 grit and place a piece in the palm of your hand and cup over the line and pull the sandpaper across it and keep doing it to where you feel you are happy with the 'crispness' of the line has been toned down. Even pressure and travel speed when pulling the paper across the sharp line.

AS if have written numerous times....do yourself a favor. Spread out some VPA and make a sharp line like the tops of your fenders and quarters...JUST LIKE the way they are. They do not have to be big test parts...just something that will allow you to see what happens. THEN...take your primer and prime it and see what it looks like. There is no way to know when to stop rounding off the top of the lines if you do not know what the end result will actually be. So...stop and do a test or a few tests with VPA parts with different top line radii to get it the way you want it. Sand the prime when you feel you got it the way you want it and then paint and clear it. I have done this back in the 'day' so I know what I get when completed.

This is also depending on if the feature line is that big of a deal to you or not.

DUB

929nitro

I am not worried about original I just don't want it to the point where the paint has a problem. If it can stay dead sharp and not have a paint issue I have no problem, just not experienced enough to know what will work. Thanks for your advice.

DUB

The paint does not know if it is going on a sharp corner or a rounded corner. It has everything to do with the PREP so the primer/paint will adhere.

Like I wrote...do a test and see for yourself. I know many times I write this and advise people to stop and do a test....and then I will get a PM from a member who did not test it first...and want to know what they did wrong or what they need to do to fix it. Seems to be always enough time to do it twice but some people can never find the time to stop a do a test first.

DUB

929nitro

Understood, Thanks for the advice.

DUB

For whatever it is worth....it will work and come out great....even if you keep them sharp. It is all about time, patience and paying attention to what you are doing and not changing the procedure when you know a procedure worked and has given the desired result.

DUB

929nitro

I never put time constraints on my work. When I am happy then I am done if I have to do something 3 times to be happy so be it. Thanks for all your help.

DUB

Great minds think alike. gettign ti doen RIGHT takes time....and i mam not afraid to put imte into making it RIGHT.


DUB

Dale002

Like DUB said It is all about time, patience and paying attention to what you are doing.
Also keeping them straight is an art. I have been working on my line for a few weeks.
I use some tape to establish one side of the line and go from there. Good thing I don't do this for a living or I would have starve by now. You seem to have the right attitude, stay on it and don't give up.
Also remember that VPA should not be used more than 1/4 inch think.

DUB

This post is NOT directed to anyone specifically.

****WARNING----LONG REPLY********
ONE TIP: I know that when looking at the line when it is the VPA colored gray/blue color.....sometimes it is hard to see the line. WELL....I take the 3M dry guide coat powder and apply it to the VPA so I can see it better....and the dry guide coat powder easily sands off. BECAUSE you plan on applying something on the VPA....so it is not like you destroy all your hard work by getting the dry guide coat powder off.

ALSO...Some words to all those who are struggling in doing body work.

If you are one of those 'type' of people who HAVE TO GET IT PERFECT...you are wasting your time. PERFECT comes later in the process. I have trained enough guys in the past who were trying to get it perfect...and after showing them the process from beginning to end....they realized on where they could stop and NOT effect the outcome of the paint job. SO...if a person NEW to doing bodywork and NOT preformed tests in applying the PRIMER they plan on using and actually see what the primer PROVIDES in filling in areas....how can a person KNOW when to STOP. I am NOT writing that you do your bodywork with overly excessive coats of primer...but there are some primers out on the market that fill like CRAZY and can be applied thick. And if your car is a NON-SMC Corvette and you plan on using a gelcoat....that stuff goes thick and you would be surprised on what it can do. And YES....I COMPLETELY UNDERSTAND that you guys who may be struggling would LOVE for a guy like me to stop buy and give advice and show how to do some things easier. But...in a way....I am doing that now. Do not get frustrated....do not throw in the 'towel'. Give yourself a BREAK and slow down and familiarize yourself with what you are using and going to use so you KNOW what it will do for you. NOTHING is WORSE than me getting PM from someone...or someone who stops by my shop who had worked for months on their Corvette....and when they shot 'something' on it...it failed. And I asked then if they TESTED it out first...ESPECIALLY if this is the FIRST time they have ever done this type of work. When you preform tests and get a result that satisfies you...then the process of using that material....as LOGIC would command....you use it the SAME as you tested it.

I will also write that it is WISE to not go past 1/4" of thickness when using VPA....BUT.....that also depends on WHERE you are applying it.....because it can go much thicker than 1/4". You would be shocked on how thick it can be used and hold up.

DUB

alexandervdr

My panel lines were all rounded too after the numerous repaints done by previous owners. For the rebuilding the fender peaks I used a mixture of laying up some fibre (there were damaged and badly repaired areas that needed to be redone) and applying gelcoat (with a brush..) on top of undamaged but rounded areas. Then used a block/sandpaper 80grid for the first cut. Then I applied a second coat of gelcoat, and once dry I taped the rough peak line end to end with masking tape with a curve as smooth as possible on one side of the peak. That became my 'edge guide' for blocking the other side of the peak, I believe I used 120 grid. Once that done and cleaned off, I applied a second strip of masking tape on the just blocked side, exactly edge to edge to the first strip. Then the first strip goes off, and the blocking can start on the now exposed side of the peak. I did not get there in one run. It took me several passes. The last stage I applied some hard body filler, but after sanding only very little of that is left. I learned that it is beter not to insist first time, and let it (my brain..) 'cool' a day or so in between blocking sessions. In my experience, slow and long strokes with the block worked better and more precise. I used guide coat too for the final passes. For proper and consistent rounding the peaks, I used a wide tip black marker (guide coat may do too). I put the peak in the center of the wide tip, and this way pulled a black line on both sides. With some sandpaper glued to a wooden stick (hard block material makes more accurate sanding possible), I rubbed carefully over the peak, holding the blocking stick at equal angle to each side of the peak. Where you cut through the black, a line appears. Keeping the width of the line consistent will lead to perfect results. I did a second pass each side at half the angle, and finally finished it with going softly over it with some 120 grid sandpaper held in my hands. Before spraying on the epoxy sealer, the wole body was blocked with 240 grid.

Note that this is not the end of it. After spraying on the 3 layers of epoxy sealer, the whole car is blocked again, including all the panel lines....Then comes the primer, and again...But as I experienced: the better the work done in the preparation phase, the less work later. Mine needed only very minor fixes.