Topic: Paint steps from bare metal **Clear finally sprayed September 16/14**

[PGF550F]

Got my 550 F tank stripped to bare metal and sanded with 100 grit, prepped for paint.


 I am hoping the paint experts can educate me if I am planning to do this right.
Etch Prime
body filler
sand
Etch prime any bare metal areas (taking care not to spray any etch on the filler)
filler/sandable primer
block smooth to desired finish
primer sealer
and then finally paint
clearcoat.

[flybox1]

your tank looks in good shape.   I went through this with my tank and it still looks really good.  prep is everything.
i'd forego the filler, and head right to etch primer and a high build sandable primer...2-3-4 good coats of high build and then dust with a cheap off color, like black.
block sand the black off with 400 and all the low areas will show. continue sanding just till the etching primer shows, then repeat the above process starting with high build again, light black coat, sand........and any tank imperfections might just be gone once sanded down for the second time. 
one nice final coat of primer,  and then you'll probably be ready for your color.

finish it all off with spraymax 2k clear.  its good stuff!

http://forums.sohc4.net/index.php?topic=105018.msg1194995#msg1194995

[Bru-tom]

great start to your tank.

I did basically the same steps as you mentioned. I however used a slightly different orientation of your list.

I did an etch prime on bare metal. (i used a 2 pack etch to create a better and more solid base)
I then sprayed a few coats of Medium solids primer onto it after a light flat (the sandable type, like going on thick). I left the etch cure for a week before i applied the MS primer. Reason i let the primer cure is that with most paints that require hardener actually shrinks when as it cures. Not letting it cure correctly may cause cracks and and in your paint later on.
After i primed with MS, i applied any filler required to get rid on small impurities.

I deliberately sprayed MS primer on the etch primer because i didnt want any chance of sanding through to bare metal.

Remember, no water while working with filler, it will absorb moisture and cause problems with paint later on too. After getting her nice and smooth, another MS primer coat and let it cure properly. Sprayed a guide coat to show any imperfections with any rattle can paint i had on hand, wet sanded until all guide coat was removed leaving nothing behind. If any guide is left, its probably in spots that you missed with filler or pin holes. If you reapplied filler or spot filler,m you need to prime once more, if you feel good about your fix, then you wont have to apply the guide coat again before wet sanding. I stop at 600-800 grit.

then youre good to go, add your colour and feast your eyes on how awesome your prep has helped get the finish you wanted. You sound like you know what youre doing and know that what you put in is what you get out..

a few pics of my tank:









it looks like a lot of filler, but i sanded it all down to almost nothing:





final prime:



guide coat:



base:



clear:



polished:

[PGF550F]

Wow, I hope my tank comes out half as good as yours. I am going with Blue as well. Trying to get as close as possible to the original Candy Sword Blue. I like the idea of using the medium solids primer over the etch to avoid sanding through to bare metal. I think that will be my approach.

I showed you the good side... Clearly. lots of imperfections to fill here



what I started with:


I have done lost of research and want to do this right, but is going to be my first time using filler so I hope it goes ok. I will dry sand only until the final stages. I am fine doing a couple applications and guide coats to get it right. In fact I fully expect that's what it will take.

[Bru-tom]

hahahaha, there are always good sides with everything

i tried to get most of my metal smoothed out from inside before hand, 8 and 10mm round bar, with a bend in the end to help persuade the metal back to original position, but its helluva tough to do being a noob. Yours will be quite tough to remove as its on the main curve and its a compound curve too. so filler is what i would settle for. remember when you sand, never go lengthwise or vertical (front to rear or top to bottom). you want to go in an X (diagonal) motion or / and \. if you know what i mean? otherwise you will get flat spots from your sanding block. Oh, and always use a sanding block, even on final sanding. your fingers apply pressure in places that you dont want and can lead to "groves" where your pads on your fingertips have gone over....

but yeah, im sure you will do great and researched it a bit. Dont hate, but check this guys stuff out, learnt a lot from this oke, he is a bit irritating to watcha t times, but he is old school and know his sh!t, i mean, it worked for me: http://www.youtube.com/user/diyautoschool

check out his techniques on the basic stuff, sanding, wet sanding, when to do what, how to do other stuff, filler etc etc...
like i said, he may irritate you, but just bear with him, you wont regret it.

The main thing is, dont rush. wait for the best conditions to spray, check precipitation and humidity. I have three weather sites open to forecast the weather before i even think of spraying  hehehe..

oh, and temp is a huge factor, i have several weather forecast sites open days before monitoring the weather and humidity(55-63% is best). i like spraying at 24-26 deg Celsius. I do this because they spray Mercedes Benz's at work under these conditions. Except they have huge dehumidifiers and and and to control their temps and humidity.

[greenjeans]

Expanding on what Bru-tom said - letting the primer and body filler cure as long as your patience will let you is a great idea.   The hardened primer and the hardened body filler will shrink ever so slightly.   And while it doesn't alwasy crack the paint, it enlarges the tiny gouges that sanding leaves behind.  Those are what could possibly show over time.  Get a good quality filler - bondo has been around for ever, but there are better choices.

Painting it youself is alwasy the most rewarding thing.  Good luck, it's going to look great.

[LesterPiglet]

With those deeper dents in your tank I would score it a bit with a craft knife to provide a good key.

My tank has had this damage since I've owned it and you can't tell once it's painted.

[calj737]

A few different opinions or suggestions:

Prime
Filler
Sand with 180-240 grit BEFORE it fully cures
Filler
Sand (until perfect. Look for small air bubbles after bondo shrinks)
Filler must be FULLY cured before paint
400 grit rough sand before paint
Base coat tack cloth wipe down
Base color (2-3 coats)
Base clear (2 coats max, 1 if metallic/pearl)
Clear coat (2-3 coats)
Wet sand 1000, 2000
Buff out fine scratches

[fendersrule]

All major bodywork should be done before priming. If you have dings/dents that are more than 1/4" deep you should tackle those with a stud welder and pull those out properly. It's not acceptable to slather Bondo on anything that's more than that. It's a personal quality thing, although many people in this thread will probably slather bondo on huge dents because I haven't heard anyone say anything about metal work. Before going down that route, you should understand the concept of a dent. A dent is always a low spot and a high spot (the ridge). You can't just fill these large imperfections with filler. If you do, look at Lester's post about how much it really takes for it to work. That's shoddy quality. Take the time and do it right.

Once the major work has been completed, THEN you do either epoxy or etch. I prefer epoxy, but many people use etch. The reason you don't want to prime before major body work is that stud welding brings about heat and will impact the adhesion of any material that is on there.

So, then give it a couple coats of epoxy or etch.

Then I move into the skim-coat stage because I'm a perfectionist. I skim coat the tank using high quality conventional filler, then I block the crap out of it moving from 80 to 180 grit using a block.

Likely, you'll need to etch/epoxy again because a lot of bare metal will be showing. So give it another coat or two of etch, and then follow it up with 2 coats of high build after flashing.

Block it again with 180 using guide coat, and then give it 2 more coats of high build.

Then wetsand using 400 or 600, seal it, and paint it.

I've used the above method to five paint cars and three bikes, all which can be shown. They are imperfection free. I feel good with people getting down on their knees and eyeing it out because I know all they will see is flat glass. A LOT of paint shops, even high quality ones, don't care about perfect flatness but I do.

The basic concept is that you want the primer material to be the thinest possible. You don't want to count on building up high build primer really thick. That leads to the concept of shrinkage. It's not meant to be thick either....I already tried that once and found cracking. It's a good thing I caught it before taking it into the paint shop.

I can show images showing this work in order, but it's doubtful the mods will make a sticky out of it.

[PGF550F]

All much appreciated help and advice. I wanted to use epoxy but it is cost prohibitive at the moment. I actually already pushed out most of that dent from inside using a bar. Got it all within about 1/4" of true, a stud welder would be ideal but just like the epoxy I can't justify it, plus I'm nervous about getting holes in an otherwise leak free tank.
As for a proper block, what do you recommend? I used a small rectangle block when I did my side covers but I am pretty sure I need something that is not as hard and maybe a little longer?

[calj737]

Given the nature of the shapes of the tank, a block is very challenging to use. I've used thick ScotchBrite pads wrapped with sand paper so they are firm enough, but flexible enough to take the convex curves.

Whatever you do or use, take your time. Professionally results REQUIRE diligent preparation and finishing. If it's not right before color goes on, it will not be right afterwards.

[Bru-tom]

I haven't heard anyone say anything about metal work.

i tried to get most of my metal smoothed out from inside before hand, 8 and 10mm round bar, with a bend in the end
(rounded and smoothed) to help persuade the metal back to original position, but its helluva tough to do being a noob. Yours will be quite tough to remove as its on the main curve and its a compound curve too.

thanks

if you look at the dent closest to the from on the tank, i is very deep and small. that metal has stretched very badly, o trying to get that puppy out might end up causing you way more headaches than necessary.

400 grit rough sand before paint

isnt 400 grit too rough before colour? especially base coat as its the most unforgiving when it comes to showing imperfections?

[fendersrule]

Sorry about that Bru-tom. Missed it.

A metal bar will work. I've sometimes used anything I could find with success. It's all about the patience and ability when it comes to that.

The Harbor Freight stud welder is actually a pretty nice tool. I don't ever see it going out soon and it's served me well. The included slide hammer is merely "fair", but works. Very awesome price.

400 grit is fine for non-metallics. 600 is what you should use for metallics. 600 is what my shop requires of me. They also shoot a sealer (usually reduced epoxy) before the base coat.

Epoxy shouldn't be that expensive. Is etch that much cheaper? Definitely use a two-part system for whatever you do.

Some tanks I get away with using a long board on the sides. Most of the time I find using a regular block is suitable enough in most places on the tank. There's going to be some tight spaces to where a small foam block is great.

[Bru-tom]

No probs mate.

Wish we had harbour freight here. I'd be spending all my cash there for sure! We are limited in SA for availability of diy tools.

Have you heard of sigma epoxy primer? Here; they use it in shipyards right after sandblasting. It's brilliant stuff, and I like that it's 2 pack. On my bike during assembly, you know you always get those chips that happen that you have no idea got there? On mine; the 2k chipped off and the sigma etch was still left behind. Which in my opinion is absolutely bloody sweet!

Iv heard guys using epoxy a lot. What is it exactly? Just another name for 2 pack paints? I have heard overhaulin mention that they use epoxy too.

[calj737]

Hey Tom - to Fender's point, 400 is fine. It's more the effort used than the grit. Put 1,000 grit in a gorillas hand and you get...

I think Fender would agree, it's all about adhesion! Most paint fails due to improper bonding of the base layers. Use too fine a grit, and you don't get enough "tooth" to bond multiple paint layers up.

The other thing I'd offer, a motorcycle paint job needs a slightly different consideration. They are often VERY exposed to rider-side damage. Meaning, pants, zippers, etc. you can out a gorgeous paint job on, then scratch the ever-living hell out of it with something innocuous on the first ride. So I approach them a bit differently than I would a car. Deeper bond, a tad more paint, more clear for "repair" buffing.

Posts like these always prove two important points: cats can be skinned in many ways, AND there is a global community of experience out there to help. Both very good things from my chair.

Cheers!

[LesterPiglet]

A little tip. If you run out of 800 or whatever, fold some 400 in half and rub it together.

[PGF550F]

ok, all great advice. I looked into Epoxy primer, I think things are just more expensive here in Canada Smallest quantity I can get it is in quarts and its 80-100$ for primer and activator... Just for primer!! I have to still keep the fridge stocked at home and the heat on, So I am going with etch that I found at the local body shop for half that price.

I have lots of time, so I am not in a rush on the bodywork. I hope to get it blocked out well, and yes, I will be using the 45 degrees in either direction when blocking. Its -41degrees C here today with 2 feet of snow on the ground, So I wont be riding anytime soon...

Here is a look at that big dent before I pushed it out.


How much filler was sitting in that dent:

You are right Bru-tom, its not easy to push those dents out. Got it the best I could but there really isn't much to get leverage off of inside the tank. I tried with the bar inside the tank and tapping with a hammer on the outside but whatever remains isn't coming out with my current skill level.



This forum is great, I know research cant replace experience, but knowing where I might go wrong BEFORE I get there is going to help immensely! Thanks guys!

[Bru-tom]

@ calj737 : makes sense the way you put it with regards to the stronger bond needed on tanks. im glad i went down to metal not knowing how the PO prepared the tank though. Aaaaan knowing that these shiny beauts scratch easily, its kinda the first thing on my mind when dressing hehehe i want my paint to last as long as i can put up with thinking ahead

@ PGF550F: wow, thats like 2.5 x colder than my freezer! i feel for you, but at least it gives you time to work on your bike, i hope! well, except the painting part of course.

now to stir the pot even more, I have an earlier cb550 tank... it had a very rusty patina on the top side...the clear on the decals were also coming off. So i decided to help preserve the tank for a few more years/months or whatever, that i slap some clear over the whole thing after a good sanding and cleaning. came out sweet if you ask me.

before:



after:





there was a dent on the right side by the badge, the metal is so thick, there was absolutely no way to remove it. I was scared to do more damage than good. so i left it, adds to the age and character

anyway, enough thread jacking, im sure you have learnt a lot from this thread, as i have. Get cracking brother

[PGF550F]

I do have an indoor heated area to work on the bike. Hopefully pick up the last few items I need to get started this weekend.

Bru-tom, Any recommendations for a better block? The one I have isn't going to cut it.

[calj737]

Hey Tom - stirring some more; there's no "clear" from the factory on these tanks. The black side panels are single stage. The color is base color, then base clear (had a small metallic in it).

Next time, take some 2000 grit and "gently" hit the surface. Tack cloth, then shoot clear. It will look great, bond well, and give you a protective layer. The existing rust, well, it will still rust, but a lot more slowly.

[greenjeans]

Given the nature of the shapes of the tank, a block is very challenging to use. I've used thick ScotchBrite pads wrapped with sand paper so they are firm enough, but flexible enough to take the convex curves.

Whatever you do or use, take your time. Professionally results REQUIRE diligent preparation and finishing. If it's not right before color goes on, it will not be right afterwards.

3M has several different shapes and sizes of rubber sanding blocks.    Give those a shot.   Any auto paint supply will have them.

[Bru-tom]

I do have an indoor heated area to work on the bike. Hopefully pick up the last few items I need to get started this weekend.

Bru-tom, Any recommendations for a better block? The one I have isn't going to cut it.

well, i used a solid rubber sanding block on some surfaces other than that some high density foam. Its sort of like rubber, but not as hard. Its what we call it here. i even used some thin pieces of wood in some places.

rubber one:

high density foam, similar to this:



 i read somewhere that your auto paint suppliers even have dual density blocks, soft on one side and harder on the other. Phone around, im sure you will come right

[Bru-tom]

Hey Tom - stirring some more; there's no "clear" from the factory on these tanks. The black side panels are single stage. The color is base color, then base clear (had a small metallic in it).

Next time, take some 2000 grit and "gently" hit the surface. Tack cloth, then shoot clear. It will look great, bond well, and give you a protective layer. The existing rust, well, it will still rust, but a lot more slowly.

wow, id swear there was some over the gold section of the decal that i could pick off with my nail? im not with you wehn you say: "The color is base color, then base clear"?

hahaha, well, i had to first take off the rough rust, which i did with 180 grit, after which i went with old 400 then put some max meyer clear over it with some matting agent.came out ok and like you said, will still rust, but not as fast

[calj737]

What I meant is: where you might have a candy blue, it's base blue, then a base clear with metallic. No topcoat.

The black side panels were only a single layer of black. This makes wet sanding precarious if you get too aggressive. Also, why the tanks scratched easily and rusted on the surfaces. The good thing is the metal of the tank is quite thick. Takes a rhino to push dents out.

[Bru-tom]

what is base clear? Thats the part im not understanding. I know that base coat here, is only thinned  (with thinners) before sprayed, no hardener is applied. The clear coat, is actually 2k clear mixed with hardener and is what protects the base colour.

here here, its a beast of a piece of metal alright