wet sanding and reclearing.

[corolla619]

so i have a spare carbon fiber hood and i am going to wet sand it and want to reclear it, all myself. seen it done before but have a few questions.

so i will wet sand with either 1500 or 2000 grit paper.

once i finish wet sanding, do i need to polish out the hood before reclearing?

if so, once i'm done polishing, do i need to do a ipa wipedown before spraying my clear?

just don't see how after wet sanding and going straight to the clear coat will make it to where you don't see the sand marks/scuffs?

thanks in advance.

 

[Rsurfer]

so i have a spare carbon fiber hood and i am going to wet sand it and want to reclear it, all myself. seen it done before but have a few questions.

so i will wet sand with either 1500 or 2000 grit paper.

once i finish wet sanding, do i need to polish out the hood before reclearing?

if so, once i'm done polishing, do i need to do a ipa wipedown before spraying my clear?

just don't see how after wet sanding and going straight to the clear coat will make it to where you don't see the sand marks/scuffs?

thanks in advance.

Start with 1500 and finish with 2000 or better yet 3000. The finer the grit the less polishing you will need to do. Yes do a IPA wipe down. After clear coating let it cure for a day and polish and then wax. Are you using a paint sprayer or a rattle can?

 

[Jumpingbean]

I've read a lot of forum posts about repainting cars as I just had it done to my Accord. The body guys recommend going to between 400 and 600 grit to get proper adhesion. I was the one to actually wet sand my car and I did it with 600. I'm not sure if it's the same with Carbon Fibre but that seems way too fine for proper adhesion....

 

[corolla619]

rsurfer,
so go 1500,2000, then 3000.

okay, but once done wetsanding, do i need to polish the hood before reclearing?

that's the part i don't get? i mean if i didn't polish it out before reclearing, wouldn't the sanding marks show up after reclearing?

rattle can. seem phenomenal results. figured i'd do it since i have a spare carbon fiber hood with a couple tiny cracks. just want to reclear for the sealing factor.

 

[Rsurfer]

rsurfer,
so go 1500,2000, then 3000.

okay, but once done wetsanding, do i need to polish the hood before reclearing?

that's the part i don't get? i mean if i didn't polish it out before reclearing, wouldn't the sanding marks show up after reclearing?

rattle can. seem phenomenal results. figured i'd do it since i have a spare carbon fiber hood with a couple tiny cracks. just want to reclear for the sealing factor.

Yes, the sanding marks will show up if you don't polish it out. All you are doing is shooting clear over clear.

 

[Jumpingbean]

If you polish it out before spraying the new clear will flake right off. I'm telling you 3000 is way too fine as is. Paint needs a rough surface to adhere to. The layer of paint will fill in all the rough surface and become some what level on the new surface.

Please if you don't believe me, this is the first google result...

What grit of sand paper should i use on my car? - Yahoo! Answers

And if you don't wait at least a few weeks before you wax it (that's wax it, not polish it) you won't give the paint enough time to cure and it'll bubble. The wax/sealant will seal the paint and won't allow the solvents to cure.

 

[corolla619]

Yes, the sanding marks will show up if you don't polish it out. All you are doing is shooting clear over clear.

okay, so steps taken are:

1) wet sand 1500,2000,3000
2) polishout the sanding marks before reclearing
3) ipa wipedown
4) reclear
5) wait a day or two, then polish and wax/seal

thanks ron.

 

[Jumpingbean]

Here's a thread I found for you that talks exactly about what you're trying to do.

Re-clear carbon fiber hood? - beyond.ca car forums community for automotive enthusiasts

I wish you luck. I definitely want to see the pics a week after you wax it

 

[Rsurfer]

If you polish it out before spraying the new clear will flake right off. I'm telling you 3000 is way too fine as is. Paint needs a rough surface to adhere to. The layer of paint will fill in all the rough surface and become some what level on the new surface.

Please if you don't believe me, this is the first google result...

What grit of sand paper should i use on my car? - Yahoo! Answers

And if you don't wait at least a few weeks before you wax it (that's wax it, not polish it) you won't give the paint enough time to cure and it'll bubble. The wax/sealant will seal the paint and won't allow the solvents to cure.

He is not repainting with a base coat just re-shooting a coat of clear.

 

[Jumpingbean]

Ya, I get that. Have a look at the second link I posted as well....

 

[corolla619]

Here's a thread I found for you that talks exactly about what you're trying to do.

Re-clear carbon fiber hood? - beyond.ca car forums community for automotive enthusiasts

I wish you luck. I definitely want to see the pics a week after you wax it

trust me, no wax will be applied for 2-4 weeks. i know it takes time(wether it's base or clear)for the chemicals to fully cure. i understand that.


i appreciate your information but not the hidden hostility.

everyone i seen reclear a c/f hood wetsands just as rsurfer applied.

my main concern is wether to polish after wetsanding or go straight to clearing after wetsanding.

nonetheless, thank you for taking the time to link me.

 

[Jumpingbean]

No problem man. I just want to see you happy with the results. There's nothing worse than spending all kinds of time on a project only to have the results disappoint you.

 

[rohnramirez]

he body guys recommend going to between 400 and 600 grit to get proper adhesion. I was the one to actually wet sand my car and I did it with 600. I'm not sure if it's the same with Carbon Fibre but that seems way too fine for proper adhesion....

That is too abrasive. 600 if you are going bb/cc, but for just cc 1000 is just right.

okay, but once done wetsanding, do i need to polish the hood before reclearing?

No. If you polish the sanding marks out, the cc will not stick. But i would dry sand it instead.

wouldn't the sanding marks show up after reclearing?

It won't. The cc will fill the sandmarks. after sanding you would want to clean the hood with some soap and water, then completely drying prior to spraying the cc.

I'm telling you 3000 is way too fine as is. Paint needs a rough surface to adhere to. The layer of paint will fill in all the rough surface and become some what level on the new surface.

I agree.

 

[Lasthope05]

okay, so steps taken are:

1) wet sand 1500,2000,3000
2) polishout the sanding marks before reclearing
3) ipa wipedown
4) reclear
5) wait a day or two, then polish and wax/seal

thanks ron.

If you are re-clearing the hood you should not be polishing it before hand or sanding with fine paper. I did a lot of prepping for repaints for resprays and learn how to paint also.

1) Wet sand with 800 grit (600grit for primer)
2) Prep sol wipe down(Very important. Several times to prevent fish eyes.)
3) Apply clearcoat
4) Cut and Polish (Look at the technical sheets of the clear. It will tell you how many hours before you can do this.)

You should not wet-sand(light grits) and polish before you re-clear it. The paint needs a ruff surface for it to adhere to. Also don't worry about the 800 grit wet sand scratches. The clear coat is going to fill them in when you do your "wet coat."

 

[rohnramirez]

If you are re-clearing the hood you should not be polishing it before hand or sanding with fine paper. I did a lot of prepping for repaints for resprays and learn how to paint also.

1) Wet sand with 800 grit (600grit for primer)
2) Prep sol wipe down(Very important. Several times to prevent fish eyes.)
3) Apply clearcoat
4) Cut and Polish (Look at the technical sheets of the clear. It will tell you how many hours before you can do this.)

You should not wet-sand(light grits) and polish before you re-clear it. The paint needs a ruff surface for it to adhere to. Also don't worry about the 800 grit wet sand scratches. The clear coat is going to fill them in when you do your "wet coat."

That is perfect, Alan. I didn't know what you guys use to remove grease on the surface before washing with soap...Prep sol it is then.

 

[Lasthope05]

That is perfect, Alan. I didn't know what you guys use to remove grease on the surface before washing with soap...Prep sol it is then.

You can use any type of "wax and grease remover" that is readily available to you as they all work effectively. I just use prep sol because I get it locally.

Oh, I also forgot to add. Remember to use a tack cloth right before you spray to remove any surface dust.

 

[rohnramirez]

i use a grease remover too before i wash with soap. usually petroleum based.

 

[corolla619]

If you are re-clearing the hood you should not be polishing it before hand or sanding with fine paper. I did a lot of prepping for repaints for resprays and learn how to paint also.

1) Wet sand with 800 grit (600grit for primer)
2) Prep sol wipe down(Very important. Several times to prevent fish eyes.)
3) Apply clearcoat
4) Cut and Polish (Look at the technical sheets of the clear. It will tell you how many hours before you can do this.)

You should not wet-sand(light grits) and polish before you re-clear it. The paint needs a ruff surface for it to adhere to. Also don't worry about the 800 grit wet sand scratches. The clear coat is going to fill them in when you do your "wet coat."

thank you very much. i will follow this procedure.

you don't think 800 grit is too rough for the clear? i'm a little worried 800 might be too rough. maybe wetsanding makes all the difference i suppose? maybe i'll hit it with 1000 grit, just don't want to eat deep through the clear all the way to the carbon fiber.

 

[Lasthope05]

No, 800 grit is actually on the light side for prepping. You are wetsand to to get a smoother and more uniform finish. There is a difference in wetsand for painting and wetsanding for paint correction. Wet sanding in painting uses 600-800 grit to roughen and prep the surface. Wet sanding in paint correction uses 1000-4000.

Using too fine of a grit will not allow the new respray to properly bond. You also dont have to worry too much about sanding through as carbon fiber hoods are gel coated are pretty hard and much thicker than standard clear. Just be smart about it and dont sand the same spot over and over again. All you want to do is rough up the surface. Unlike in detailing your are not trying to remove defects so you're not continuously sanding one spot.

What is the current condition of the hood? IF the gel coat is not compromised/oxidized you could use a scuff pad in lieu of sand paper if you are scared of sanding through to the weave.

3M™ Paint and Body Scuff Pad, 03193, 6 in x 9 in, 20 per case

 

[Apokiliptik1]

No, 800 grit is actually on the light side for prepping. You are wetsand to to get a smoother and more uniform finish. There is a difference in wetsand for painting and wetsanding for paint correction. Wet sanding in painting uses 600-800 grit to roughen and prep the surface. Wet sanding in paint correction uses 1000-4000.

Using too fine of a grit will not allow the new respray to properly bond. You also dont have to worry too much about sanding through as carbon fiber hoods are gel coated are pretty hard and much thicker than standard clear. Just be smart about it and dont sand the same spot over and over again. All you want to do is rough up the surface. Unlike in detailing your are not trying to remove defects so you're not continuously sanding one spot.

What is the current condition of the hood? IF the gel coat is not compromised/oxidized you could use a scuff pad in lieu of sand paper if you are scared of sanding through to the weave.

3M™ Paint and Body Scuff Pad, 03193, 6 in x 9 in, 20 per case

agree also would not hurt to spray an adhesive promoter before laying down clear.do not polish before clearing as to like the other posts nothing will adhere.if the hood is in good shape you might be able to just scuff it real good with grey scotch pads and wipe it down then clear. just my take