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Topic Review (Newest First)
02-13-2013 10:00 AM
69 widetrack And isn't it always the job that has to go by 5 o'clock, or the one that you take all the special care in cleaning, blowing down, tacking and making sure your booth could be on the cover of Good Housekeeping and what happens, for some unknown reason you get everything from dirt and fly's to small barnyard animals in your paint, (bit of an exaggeration....I'm pretty sure the baby goat stuck to the roof was planted there by one of the guys in the shop...LOL...no hoof prints on the hood or deck lid).

Ray
02-13-2013 09:48 AM
painted jester Did a Model 'A' Riddler car years ago on my last Coat of clear a Crane fly landed right in the center of the cowl vent spread eagle just perfect The owner liked it and stopped me from picking it out!!!! so I cleared it for posterity LOL It really looks cool (like we planed it) It didn't win Riddler though it came in about 5th probably because of the "FLY" LOL

Jester
02-13-2013 09:44 AM
MARTINSR
Quote:
Originally Posted by 69 widetrack View Post
Everything you just said is so true...even when you do your best to do everything the way it's supposed to be done. That's why I always get a kick out of guys that say "I've done it X amount of times and never had a problem"....I wish I was that lucky....anybody that says they've never had a problem either hasn't been in the trade long enough or is outright lying.

Ray
Very true. And just how screwed up can you do something that won't get out the door? I mean, "It didn't explode when I did it so it works".

Brian
02-13-2013 09:35 AM
69 widetrack I love your comment about the moth in the booth...one time I remember hunting down that same moth, it was a beautiful colored creature...so I cornered it, stepped on it and went back to clearing the vehicle and be damned if not 5 minutes after I was done I looked at the car and that SOB was doing the backstroke on the hood...LOL

Ray
02-13-2013 09:18 AM
painted jester Ray:

Jester
02-13-2013 09:13 AM
69 widetrack Everything you just said is so true...even when you do your best to do everything the way it's supposed to be done. That's why I always get a kick out of guys that say "I've done it X amount of times and never had a problem"....I wish I was that lucky....anybody that says they've never had a problem either hasn't been in the trade long enough or is outright lying.

Ray
02-13-2013 09:01 AM
painted jester Murphy's Law ("If anything can go wrong, it will")

I really believe in it!!!, If there is a moth in my booth and I lose it and don't kill it, When I run my last pass and shut the lights! It will be right in the center of the hood in the morning LOL! If I have a doubt I don't do it! As I get older I've seen Murphy come into play through out my life! If I Use a new product that isn't supposed to shrink there's Murphy LOL it shrinks! Pick up my coffee cup and Murphy makes the handle come off and it spills into my freshly mixed paint cup! Primed a car then used Sikkens white sealer and the
filler color bleeds through the primer and the sealer! Sikkens says it cant happen Barry said its rare but then I get on here and guys that use Sikkens exclusively (all the time) say " Everyone knows you have to shoot a good sealer before shooting Sikkens sealer" In all my years Ive never heard of having to shoot sealer before shooting sealer But then there's Murphy ! I yelled at my son when he was about 5 "Get out of that tree before you break your neck" Murphy pushed him out of the tree and broke his arm

Now I'm old and look for Murphy every where! If I see anything that might happen I alleviate the situation because I know it will happen!


I think all of us have met Murphy at one time or another LOL

It just seams like if your working Glass He's Right there watching for his chance!!!!!! You mix a cup of resin cold your in the middle of applying a layer and the temp goes up 20* in in 3 min. and your brush comes out of the cup and your resin is jelled Your glass is layed out smooth and well coated and rolled (no bubbles) You come back and lo and behold there's a wrinkle with air under it LOL

Jester
02-13-2013 08:07 AM
69 widetrack At this stage of the game your best bet is to not worry about it and enjoy your truck. Perhaps, looking on the bright side, if it does crack in the future, you can repair it then and you will know what not to do. I realize that it's a small consolation.

Currently I'm turning a Model A Ford 4 door into a 1/4 truck. The back section of the 4 door car was turned into the back of the cab. It was a lot of shrinking, stretching, hammer and dolly work but when it was done, a minimal amount of filler was used. All I'm really trying to say is that the extra work put into getting the sheet metal in the shape it needs to be pays off dividends when it comes to the longevity of the vehicle, not to mention the peace of mind knowing what's underneath that shiny paint.

I asked you who gave you the advice on how to straighten out the roof of your truck. The reason I asked was because quite often advice is given and sometimes it's incorrect. There's nothing wrong with questioning any ones advice or getting a second opinion. A rule of thumb if you question someones advice and you have any concerns and they say "don't worry, I've done it hundreds of times and never had a problem", get a second opinion, it's difficult enough to get through 20 jobs, doing things correctly with the same procedure and products and not have problems.

In the auto body world, there are painters and there are applicators, the painter is the person that cares about every job they do and takes pride in workmanship and if a problem arises, often has the knowledge and the ingenuity to fix the problem in the paint booth. There are body guys and then there are technicians, the technician understands how metal reacts with respect to impact (collision), heat (welding), fabrication (putting metal into the shape required for a repair or custom application) and has an understanding of current products and how they should be used. A body guy gets it close and carves the shape of the vehicle with the filler of choice. Just so you understand, there is nothing wrong with filler when used properly within the tolerances set out by the manufacturer.

I wish you only the best with your vehicle.

Ray
02-13-2013 06:44 AM
M5StudeGuy
Quote:
Originally Posted by NEW INTERIORS View Post
You say you added more resin on top of it to flow it out... Resin is brittle without the chop mat... The mat is what holds it all together.. Resin by it's self will crack very easy....
I guess I should of been clearer.
The resin they put on top was just to make sure all the matting was saturated, and no air bubbles.

Someone asked who put it on: It was a body shop guy with several years experience
I guess after investing $25,000 in this project I'll just have to sit and hope
Thanks
02-12-2013 11:53 PM
NEW INTERIORS
Quote:
Originally Posted by 69 widetrack View Post
QUOTE
People can make it stick to metal.. BUT... Like I said,, On a fool.. I'm 240 and if you step on that floor just right... It will pop off the metal... Plus for some reason.. I have seen where people covered rust holes and it rust even more... Maybe the resin does something to the metal...Don't know...


"I played with glass a little.. Building this car with no mold...Here's some fenders I hand made as well..made a buck,then made a mold.then made the fenders,,,More on that in my journal.."END QUOTE


Fabulous work Randy...pure talent, and proper use of fiberglass in the true definition of use of fiberglass. That has to be some of the best work I think I've seen. For anyone following this thread take note, this is what and how fiberglass should be used.

And M5StudeGuy, I would very much like to say that you don't have anything to worry about but as New Interiors said...I wouldn't have done it like that either, it's not the proper repair or use of the product. You may be fortunate and not have a problem for quite some time (and I sincerely hope that is the case). A lot depends on how thick and (as mentioned) how much resin you used...is it a daily driver? Where you live and temperature changes will effect the life of the repair as well. If you live in a climate where you have drastic changes in temperature the expansion and contraction differences between the metal and the fiberglass will eventually cause the fiberglass to let go. The fact that you put a coat of Epoxy primer on prior to the fiberglass will help, it'll act like a cushion for the inevitable differences in expansion and contraction. This, although different, is similar to cars that came from the factory with lacquer paint...in cold then warm climates, the lacquer paint was prone to cracking more readily than in a more stable climate.

I do have a question, where did you hear that this was a proper way of repairing your roof? The reason I ask is because I'm very cautious when I give advice on this forum for reasons just like this.

I wish you only the best.

Ray
Thanks for the kind words..
02-12-2013 11:37 PM
69 widetrack QUOTE
People can make it stick to metal.. BUT... Like I said,, On a fool.. I'm 240 and if you step on that floor just right... It will pop off the metal... Plus for some reason.. I have seen where people covered rust holes and it rust even more... Maybe the resin does something to the metal...Don't know...


"I played with glass a little.. Building this car with no mold...Here's some fenders I hand made as well..made a buck,then made a mold.then made the fenders,,,More on that in my journal.."END QUOTE


Fabulous work Randy...pure talent, and proper use of fiberglass in the true definition of use of fiberglass. That has to be some of the best work I think I've seen. For anyone following this thread take note, this is what and how fiberglass should be used.

And M5StudeGuy, I would very much like to say that you don't have anything to worry about but as New Interiors said...I wouldn't have done it like that either, it's not the proper repair or use of the product. You may be fortunate and not have a problem for quite some time (and I sincerely hope that is the case). A lot depends on how thick and (as mentioned) how much resin you used...is it a daily driver? Where you live and temperature changes will effect the life of the repair as well. If you live in a climate where you have drastic changes in temperature the expansion and contraction differences between the metal and the fiberglass will eventually cause the fiberglass to let go. The fact that you put a coat of Epoxy primer on prior to the fiberglass will help, it'll act like a cushion for the inevitable differences in expansion and contraction. This, although different, is similar to cars that came from the factory with lacquer paint...in cold then warm climates, the lacquer paint was prone to cracking more readily than in a more stable climate.

I do have a question, where did you hear that this was a proper way of repairing your roof? The reason I ask is because I'm very cautious when I give advice on this forum for reasons just like this.

I wish you only the best.

Ray
02-12-2013 10:08 PM
NEW INTERIORS
Quote:
Originally Posted by M5StudeGuy View Post
OK.. I'm reading this thread and you folks are getting me worried...
I applied fiberglass to the roof of my truck. I was told it was fine..
SO let me detail what I did and give me your thoughts.

I stretched the cab of the truck and it wasn't quite level,.. so we added fiberglass to fill the low spot. We did this:
Sanded the metal with 40 grit paper.
Put on epoxy primer.. sanded again with 80 grit.
Then we put on a layer of resin, a layer of fiberglass mat, resin, mat and then resin (all at once). Stuff is hard as a rock.
Then we put fiberglass out of a can on top of that to help with the small low spots (some on top of the fiberglass/resin mix, and some on bare metal), and finally bondo to make final adjustment to make it perfectly smooth.
We sanded with 40 grit between each application.

SO please tell me I'm not going to have any problems...

I wouldn't have done it like that...I seen where it popped off the metal over time... You might get lucky,, Then again you might not... I would say you can be ready for it to pop off one day...I hate to be the one to tell you.. And I wish I had a crystal ball to say for sure,, I would have used short strand body filler instead of fiberglass..

Another thing is.. Resin is not any good by it's self... You say you added more resin on top of it to flow it out... Resin is brittle without the chop mat... The mat is what holds it all together.. Resin by it's self will crack very easy.... When your doing fiberglass work... You want just enough resin to wet out your chop mat.. The less resin you use,, The stronger the part will be... Using more resin then you need is a big nono... Ever seen where they make custom fiberglass parts in they suck out as much resin as they can once everything is good and wet... There's a good reason behind that..Good luck with your truck..May last a while,, But it's hard to say just how long it will last..
02-12-2013 09:52 PM
painted jester
Quote:
Originally Posted by speedydeedy View Post
You seem to know a lot about the different resins. How about explaining Isothalic resin,I think I spelled it right.I was always taught that this was the best for making new car parts because it remains more flexible.Set me straight if I am wrong or explain it better if I am right.I have made and repaired a lot of race and street car glass parts but I am better at doing than writing.


Isophthalic resin I think your talking about? Its just a different product then the usually used Vinyl Ester resin when repairing boats in the top end shops!

Its like comparing the old Bondo Brand from 50 yrs. ago To the new fillers of today!

Jester





I found this so I'll copy and past! I type too slow to explain what you need LOL I"m not a Chemist LOL

"There is a big difference between isophthalic polyesters and vinylesters, worth every penny of extra cost. In any polyester, ortho- or iso-, the monomer is styrene (45% to 48% by volume usually). The polyester molecule is dissolved in the styrene. A peroxide compound, usually methyl ethyl ketone peroxide (MEKP) is used to catalyze the resin, which cross-links with some of the styrene, but not all of it. What styrene is not used in the chemical reaction flashes off, giving that fiberglassy smell, leaving microscopic holes in the laminate. It is through these holes that water passes during osmotic blistering.

Vinylester resin also uses styrene as a monomer in about the same proportions. And it also uses peroxides like MEKP as a catalyst. What is different though is that practically all of the styrene is used in the chemical reaction. Most of the styrene catalyzes with the vinylester, and the remainder crosslinks with itself, which makes polystyrene molecules within the resin. This closes off the vast majority of the microscopic holes in the resin, and this is why vinylester is so impervious to osmotic blistering. This is why chemical storage tanks, such as underground gasoline tanks, are always made with vinylester resin.

I always specify vinylester resin for blister protection and repair if the client does not want to use epoxy resin. Epoxy, by the way, is 100% solid, and therefore is the best blister barrier material."

As told by 2 big resin manufacturer tech's
"that the Iso. resins have also excellent resistance to blister. Without getting into specific manufacturers - They sell this particular Iso. as a 'matched performance system' for use with their marine gelcoat for use in 'marine' and other similar industries. This particular iso. costs as much as my gelcoat, but the V/E is about 75% more expensive, it's a DCPD modified V/E specifically for skincoats. They describe the iso. resin that if used with their gelcoat it offers a 'superior blister resistance'."
02-12-2013 09:43 PM
painted jester
Quote:
Originally Posted by M5StudeGuy View Post
OK.. I'm reading this thread and you folks are getting me worried...
I applied fiberglass to the roof of my truck. I was told it was fine..
SO let me detail what I did and give me your thoughts.

I stretched the cab of the truck and it wasn't quite level,.. so we added fiberglass to fill the low spot. We did this:
Sanded the metal with 40 grit paper.
Put on epoxy primer.. sanded again with 80 grit.
Then we put on a layer of resin, a layer of fiberglass mat, resin, mat and then resin (all at once). Stuff is hard as a rock.
Then we put fiberglass out of a can on top of that to help with the small low spots (some on top of the fiberglass/resin mix, and some on bare metal), and finally bondo to make final adjustment to make it perfectly smooth.
We sanded with 40 grit between each application.

SO please tell me I'm not going to have any problems...
Stud guy:
I would have to be there when you applied the layers! I couldn't tell you what could have gone wrong with your process! I could only guess? I could advise you to paint it white and keep it in the shade! Or pad and vinyl the top, like they do with bad chop jobs! Sorry man I didn't even want to comment on your post If the guy that did it is a good glass man and he said it would work trust him! He must have done it before.

Jester
02-12-2013 09:33 PM
speedydeedy
Quote:
Originally Posted by painted jester View Post
Vinylester resin, Formaldehyde Resin ETC cant forget those! There is also a different coating on the glass fiber for the different types of resin your using so the resin can bond to the glass or other fibers!

No difference in the non waxing and waxing resins, There's a big difference LOL, Or there would only be one formula! Like the cheep general purpose economy resin cut rate shops use! And if your doing overhead or vertical work your large areas of woven cloth or mat would fall or slide off!

Laminating resin dries tacky! You don't sand laminating resin, Its tacky to hold your next layer in place and to aid adhesion when applying more layers and helps the Finnish coat adhere to it and the product or repair dries hard and can be sanded or prepped or jell coated!

A lot of custom parts are built using epoxy resin. The issue is efficiency and cost. Epoxy, though a superior technology, costs 2 to 3 times as much as polyester resin and it must be washed between layers,polyester laminating resin needs no prep between layers! Both Epo. and Poly. resins can be used to mold fiberglass, but polyester is more controllable by the amount of catalyst added so production time is reduced- get the finished part out of the mold and get another one started. Epoxy resin is used to make the molds that polyester resin fiberglass parts are made in though!

Epoxy molded fiberglass must also have a surface finish applied! So Polyester resins are used for this! First gel coat the mold and then the laminated layers added and out pops a shiny new part.

249 polyester resin, it drys clear as water, other polyester resins have a blue or green tint

vinyl ester resin is stronger/tougher but is not as clear so not used much with color tinting or carbon fiber.

epoxy resin is the strongest and bonds better with automotive plastics. When using it with carbon fiber it must be U.V. protected in sunlight with a good non yellowing clear. Epoxy is no good for any kind of heat and it will become rubbery at a low temp. It does resist spider cracks but isn't as flexible as polyester resin.

I can apply heat to a Corvette top, rear, front fender corner and apply pressure to get it back in position apply cold and it will stay there! you cant do that with epoxy resin parts!

Jester
You seem to know a lot about the different resins. How about explaining Isothalic resin,I think I spelled it right.I was always taught that this was the best for making new car parts because it remains more flexible.Set me straight if I am wrong or explain it better if I am right.I have made and repaired a lot of race and street car glass parts but I am better at doing than writing.
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