Help on prepping a stainless steel motorcycle tank.

[brushit]

Hi everyone out there. I am not a beginner, but have been airbrushing helmets for many years. My friend has sent me brand new Harley Davidson tank and fenders to paint for him. Silly me, i thought they would come undercoated or something. No way, they are raw stainless steel with many machining grooves , scratches etc. Can anyone please help me out here with the correct method to prepare for painting. See pics. These grooves would be half a millimetre deep and can`t sand stainless . Should i fill them or what. Would be grateful for any replies. Thanks.

 

[michael13]

I don't understand when you say you can't sand stainless, yes it's a hard metal anyway - If the grooves are to deep to fill with a high fill primer then I would:
1.sand with 40- 80p sand paper on a da sander to provide tooth on the metal for a skim coat of body filler. I would then sand and shape the filler finishing with 100- 180p sandpaper.
2. Then spray with either a etch primer or epoxy primer followed by a primer filler and sand finishing with 800- 1000p wet/ dry. Alternatively you could use a hybrid epoxy like HOUSE OF KOLOR KD 3000 then you only need one primer. (Follow tech sheets)
3. Base, airbrush, clear

Hope that works for you

 

[markjthomson]

Yup, check out high build primers... sounds like truck loads of prep work...

 

[brushit]

Hi everyone out there. I am not a beginner, but have been airbrushing helmets for many years. My friend has sent me brand new Harley Davidson tank and fenders to paint for him. Silly me, i thought they would come undercoated or something. No way, they are raw stainless steel with many machining grooves , scratches etc. Can anyone please help me out here with the correct method to prepare for painting. See pics. These grooves would be half a millimetre deep and can`t sand stainless . Should i fill them or what. Would be grateful for any replies. Thanks.

Thank

I don't understand when you say you can't sand stainless, yes it's a hard metal anyway - If the grooves are to deep to fill with a high fill primer then I would:
1.sand with 40- 80p sand paper on a da sander to provide tooth on the metal for a skim coat of body filler. I would then sand and shape the filler finishing with 100- 180p sandpaper.
2. Then spray with either a etch primer or epoxy primer followed by a primer filler and sand finishing with 800- 1000p wet/ dry. Alternatively you could use a hybrid epoxy like HOUSE OF KOLOR KD 3000 then you only need one primer. (Follow tech sheets)
3. Base, airbrush, clear

Hope that works for you

Thanks for the tips. Sounds like good advice. I just panicked a bit as have been used to just doing helmets , bonnet scoops etc. and just filling small scratches or chips. Anyhow will be good experience as never done a Harley tank before. The only experience i`ve had with stainless steel is that it`s a mongrel to drill. Thanks mate.

 

[haasje dutchairbrush]

-That first needs to be filled out and made smooth with a filler (loads of sanding) but all of that has been described above. This isn't the easiest to do right though and it being not one of the cheapest bikes you are working on you might consider outsourcing this part to make sure its done correctly.

-What hasn't been mentioned but is verry important is that that tank also needs to be sealed on the inside! If you don't do this fumes will work their way through and in a couple of years the paint will start to "bubble up". I have no clue how the sealing works (ask a body shop) I did see the result when it hadn't been done though (came in for repair and had to be completely redone)

 

[brushit]

-That first needs to be filled out and made smooth with a filler (loads of sanding) but all of that has been described above. This isn't the easiest to do right though and it being not one of the cheapest bikes you are working on you might consider outsourcing this part to make sure its done correctly.

-What hasn't been mentioned but is verry important is that that tank also needs to be sealed on the inside! If you don't do this fumes will work their way through and in a couple of years the paint will start to "bubble up". I have no clue how the sealing works (ask a body shop) I did see the result when it hadn't been done though (came in for repair and had to be completely redone)

Thank you so much for the tip on sealing tanks. Am having them professionally done at the moment. ( Split tanks in 2 parts ). Also tanks and fenders are not stainless, just some sort of alloy. Have bought all the etch primer and high build primers for the job, and body filler for some small dents here and there. Now the hard work starts before i get to the fun bit, the artwork. Thanks to all for constructive tips.

 

[MeeshellMP]

Yep...all answers are correct..happy sanding !

 

[Squishy]

Ugh brand new Harley tanks are the worst! You think that they would at least be smooth and straight, but no, a lot of filling and then levelling out and shaping, sanding re doing etc before you even get them to the point they are ready to be primed. And yes to the sealer for sure!

 

[MeeshellMP]

Yep...gonna be a long journey for ya my friend

 

[brushit]

Ugh brand new Harley tanks are the worst! You think that they would at least be smooth and straight, but no, a lot of filling and then levelling out and shaping, sanding re doing etc before you even get them to the point they are ready to be primed. And yes to the sealer for sure!

I`m prepared for the journey and so is my customer who is also a good friend. Have done work for him before and he pays me well. He is paying for the tank sealing, etch primers, high build primers , and is having the tanks bead blasted, which should make my job a little easier. ( i hope )

 

[brushit]

Preparing new metal motorcycle tanks. Am part of the way through preparing tanks for airbrushing. Have put in many hours body filling and sanding. Have sprayed etch primer and high build primer. As weather is really hot here at the moment, surface is rough , with dry overspray which couldn`t be avoided. Need advice on either to dry sand or wet sand before base coat. Also the grit of the paper. Thanks.

 

[MeeshellMP]

Dry sand. @Squishy what grit? (Too tired to think)

 

[Hardlec]

Suggest options to the customer and let him/her choose; the customer is always right.

Harbor Freight sells an amazing tool called an air eraser. It is a grit blaster that looks like an airbrush. At pretty low pressure for a grit blaster; 40 psi, it can clean delicate items without taking off much metal.

I use baking soda as a grit to remove old paint from tin soldiers. It leaves a very fine satin finish great for primer.

Sent from my NS-P10A6100 using Tapatalk

 

[michael13]

I always wetsand uro primers. I would recommend 800p - 1000p

 

[Squishy]

Sorry, missed this. I wetsand too, no dust, and water keeps the surface clear so you can feel that its flat and smooth.

Depends how rough the finish is, I would start with something higher, and if that wasn't aggressive enough, go down until its effective. I'd rather do that than go too hard as you can make much more work getting those scratches out.