Top plate sanding

[PS2500]

Hello all,

I'm about to start what I expect to be a protracted build, due to time constraints, of an Eros tape amp. I've been looking for threads on preparation of the top plate for Bottlehead kits. I'll be spray painting mine with a few coats from an aerosol can.

From the several threads I found about painting, I couldn't get a clear idea of what people are doing about the brushed pattern on the top plate. Does this need to be completely sanded off? And if so, are several grades of sandpaper recommended?

[Doc B.]

What will you be painting the panel with? If you are using a thicker coating like Hammerite just wipe the panel with acetone or lacquer thinner before spraying. The brushing creates a very good "tooth" for the paint to adhere to and the paint levels over it just fine. If you are using gloss black or something equally tricky to make look good you will probably want to use a primer first and sand that up to 600 grit before laying on the top coat.

[caffeinator]

The brushed finish provides a great base for most spray paints - I've never had a problem applying Hammerite type finishes with respect to the plate itself.

You mentioned multiple coats, so I wanted to caution about the recoat time issue that I have experienced.  Many spray paints can be reapplied within a relatively short time with good results, but be careful about recoating after more than a short time.  For example, I"ve had good results painting top panels in warm conditions recoating in about 15 minutes.  However, when I recoated after a few days, even in warm conditions, the recoats tended to fisheye badly.  I researched a bit and found this is a common problem - when the recoat times are given as 'within 15 minutes or after 10 days' - believe them.  Had I followed label instructions more closely I probably wouldn't have had this problem.

Different paints may vary, of course, but this has been the sole source of top plate painting issues I've had with numerous BH kits.

[Paul Birkeland]

You mentioned multiple coats, so I wanted to caution about the recoat time issue that I have experienced.

You're always welcome to come over and lay down some powder.

-PB

[Doc B.]

Yes, very good advice. I have also tried as much as possible to adhere to the program of only shooting paint when the humidity is down around 50% or lower and the temp is above 65F. Not easy to find those conditions in the Pacific Northwet. I also warm the rattle can in hot water before spraying, and shake it every minute or so as I lay on the paint.

With Hammerite the trick I have found is to lay on one medium-light and then two medium coats just a couple minutes apart. If the one coat fully sets up before the next is laid on the hammered pattern won't form as well. Luckily with the panel sitting flat one does not have to worry much about sags or runs, so one can err on the heavy side.

Though the common opinion is "rattlecans suck", one can do a decent job with some practice. This tank was done with rattlecans.

[PS2500]

I'm likely to use a thinner coating, so probably need to sand it from what I'm reading here.

When I did the bell, I didn't pay much attention to time between coats, mostly did about a week after the last one, and went up to four coats or so with no primer. Basically I was experimenting. Hand painting was disastrously bad - that sure as hell isn't one of my skills - so sanded back to bare metal and started again with spray paint. The results are good, to my eye. Not silky smooth, but an even coating with a very fine "graininess" to it - I don't know the exact word that would be used. Better result than I had expected. That's what got me thinking about going for the top plate as well. I was going to leave it unpainted like my previous build.

I have two spray types, acrylic and lacquer. The only one I've tried out so far is the acrylic. This is the first time I've had anything to do with spray painting, and done very little painting in my life anyway. Urban apartment dweller for the most part.

[4krow]

  I have to say though I am not great at any type of painting, there is NO doubt of the value that the instructions provide on the can. And, for what it's worth, the quality of paint seems to vary quite a bit, unfortunately. Soo many paints simply do  not  stick! Yes, preparation is vital, yet I have steered towards truck bed liner sprays these days. In that event, the surface is rough and not so easy to clean. Guess you have to pick your battles. If I had a way to do it, I would only use powder coat finishes and be done with it.

[Deluk]

Just a comment. Don't try and sand Hammerite or any other hammered finish. Things won't go well and you'll regret it.

[PS2500]

Just a comment. Don't try and sand Hammerite or any other hammered finish. Things won't go well and you'll regret it.

Thanks. Though I've never found Hammerite or any equivalent in this country so far.

[Deluk]

What country? Hammerite is a trade name the same as Hammertone(?). I think this type of paint is available world wide. Hammerite certainly has had some chemical changes due to the nanny state and IMO has never been as good as some of its fans make out. I do use Smoothrite, I find that better but it doesn't have that characteristic hammered finish.

[PS2500]

What country? Hammerite is a trade name the same as Hammertone(?). I think this type of paint is available world wide.

Japan.

In my experience, Coca Cola is "available worldwide".

[Paul Birkeland]

There is a distributor for Rustoleum in Japan:

https://www.rustoleum.com/pages/about-rust-oleum/Global/asia/

[PS2500]

There is a distributor for Rustoleum in Japan:

https://www.rustoleum.com/pages/about-rust-oleum/Global/asia/

You're right. Though after a quick search, I still don't really see any of the hammered finish paints here. To be honest, I'm not really hunting for it for my build, I was interested in the past when reading about it, but I've never seen it on a store shelf here, and I wonder if it's just not popular. Usually though, if the product of an overseas company isn't available, there's some kind of equally high quality Japanese equivalent. For hobbies such as audio, when I read English language sites, I often have to find what the local (Japan) equivalent of a particular recommended product is, or decide if it's worth getting it from overseas. Applies to cleaning fluids and the like...