A first kit for Christmas: JMA-1L

[Sonic Mountain]

Just start with the roughest/coarsest one first. Probably 180 (or close to that)

As much as possible sand in the same direction as the grain. It is difficult around the ends of the guitar.

Once you start you will notice marks from the factory tools. Try and remove these as much as possible with the 180. Avoid sanding in one spot too long. You should aim to evenly sand the whole body. (I haven't done a natural finish as yet, but I think you would be safe to putty after the 180 - somebody may correct me)

Once it feels smooth move onto 240 - as you work with that sandpaper, you will see the scratches you made with the 180. Use the 240 until you can't see or feel the 180 and then move onto the next grade of paper and so on.

This can be a bit boring and its hard work, but the better job you do of it, the better the finish will be in the end.

[Volgar]

Ok, thanks,
I do a mistake by buying the filler (who was not one), I think this is better : Wood filler ?
No ?


What grade of sandpaper should I go to before applying the filler?
And after ?

[Volgar]

That filler looks correct Volgar.
Use the grades of sand paper that Sonic Mountain posted both before and after using the filler.

Thanks, Can you say me the higher grade I need to use ?

[Volgar]

I will paint it

[Sonic Mountain]

Ok, so if you are painting, sand the body with 180. You don't need to be quite as picky with the marks. Then you can probably do the grain fill and sand it back with 180 as well.

My experience is with automotive spraying. I will share what I do, other people may have advice and suggestions.

In Australia we have a couple of different DIY automotive stores that stock a range of spray paint in cans. I am not sure how well this will translate, hopefully it makes sense.

After you have filled the body and sanded back you would spray with an 'Etch Primer' - this bonds to the guitar and also allows paint to stick to it. Do a couple of coats of this. You can sand this with 240 - 320 (or whatever grade you have available close to that)

Next I like to use 'Hi-Fill' or 'Spray putty' This is ideal for removing small marks and scratches. You can spray this in several light coats, leaving about 5-10 minutes in between to build a really thick layer.

Let this dry for as long as possible. I think a week in warm dry weather minimum. Now you can sand this back with 400-600. You should use a firm block with the paper wrapped around it to get a nice flat even surface.

When you are sanding, let the paper do the work. Don't press too hard and change the paper regularly. It will get clogged and wear down.

At this stage you should have a nice flat smooth feeling guitar. It is ok if you sand through to the primer a bit, but not the wood. If you do that you need to prime it again.

Now you need a product called 'Primer surface' or 'Undercoat'. Give it a good coat with that, let it really dry out again and sand with 800-1200

Now you can spray your 'Top Coats' (this is the fun bit). You should make sure all your paint is from the same product range so that it is compatible. If you are doing a solid colour you can just spray multiple coats of that. Leave 48- 72 hours between coats and give it a lift sand with 1200-1500 between. After a few coats give it another really good chance to dry out. A week minimum, but the longer the better for it to get really hard.

If you are doing a metallic. Do the same as above, but do a randomised spray pattern for the metallic coat. Let it get hard and then spray a clear gloss over it. You do not need to worry about sanding the metallic. Build up a good coat of clear and then, the same as above, let it get really hard.

Once the paint is very dry you can cut and polish it. Use 1500 -2000 'Wet and Dry' sandpaper to get the surface really flat. I would use a soft sanding block for this. It will look milky and dull, but should be very smooth. Be careful around any drill holes or openings. Don't let the water get into the wood or it will swell up and ruin the paint job.

Next, use some 'Cutting Compound' to polish up the surface. You can do this by hand, but it is a lot easier with a buffing machine. This is available at automotive do it yourself stores. You should be able to get all the polishes you need there as well.

After you have a uniform finish move to the next grade of polish. I use a 'Cut & Polish' followed by plain 'Polish'.

After that you can use a 'Swirl Remover' and 'Wax' to really make it shiny, but I don't bother as they all get marked up fairly quickly when playing.

[jarrod]

After the grain fill you need to seal the wood before you apply any paint or in a couple of months
You will find your paint will sink into the grain.
Second : you are applying far to much paint process to your guitar.
Seal / etch / very thin white primer ( not filler primer )
Only clear coat over metallic or stain as your base colour does not need clear it to can be polished with out clear.
Sanding paint coats to 600 to 800 gritt.
Too many coats of paint just kills your tone and is un necessary.
Also metallic has what is called a flip in the paint, keep in one direction and over lap each line by 50%, only two thin coats should be needed.
Keep you coats super thin ( they cure quicker and more effectively, and if it’s Acrylic or Nitro leave it two to three weeks before you polish it.
Sorry to butt in bro but I had to correct a few things.

[Sonic Mountain]

All good man. I'm not a trained professional, I've just done it as a hobby for a long time- although it's usually painting bodywork. I expected corrections. I'm very wary of sink back, but have not had any problems with it so far, so long as you give each coat a really good chance to harden before the next it seems fine.

[jarrod]

Basswood and tight grain timbers you can get away with it.
Ash etc... pain in the arse

[Sonic Mountain]

Yeah I learnt that the hard way.

My method is pretty wasteful as I end up sanding off a lot of the paint I apply. But at the same time it makes any goofs easier to fix. I also find that the pressure pack cans don't lay down anywhere near as well as the gun. So I end up doing more coats as insurance. I keep threatening to setup a booth and get my gear out but I still haven't got around to it. Anyway, all good, the best thing about this forum is the cross section of advice available.

[FrankenWashie]

Yeah I learnt that the hard way.

My method is pretty wasteful as I end up sanding off a lot of the paint I apply. But at the same time it makes any goofs easier to fix. I also find that the pressure pack cans don't lay down anywhere near as well as the gun. So I end up doing more coats as insurance. I keep threatening to setup a booth and get my gear out but I still haven't got around to it. Anyway, all good, the best thing about this forum is the cross section of advice available.

Yep, that sounds familiar.