Grand Angus Project, Part 6: Update on some issues

Well I wasn't going to make another post until the guitar was fully cured and I'd started the final sanding and finishing, which (if on schedule) would have only been about a week away. But it's not on schedule, and I wanted to post an update now as to why rather than wait until it's done and do it all retrospectively. Because I'm good like that.

When I last posted I was finishing off the clear coats of lacquer. Or so I thought. I'd done about 7 coats of clear lacquer and went to give it a good old rub down so it would be nice and smooth for the last coat or 2.

I ran some sand paper over the body for 3 or 4 strokes, then looked at the paper, and the dust in the paper was red - the same red as the finish that should be under about 7 coats of clear lacquer. This was me, yeah, "what the f*ck?!" After that many coats, the lacquer definitely should have started to build and the grit coming off the guitar should have been white.

Obviously the lacquer wasn't building as quickly as I expected it to. This meant one of two things; either my expectations were off, or there was something wrong with what I was doing. So I did what any sane person would do; go on the internet and ask strangers for advice.

I hit up the Official Luthiers Forum and asked the question. Advice was fairly unanimous that my 2:1 ratio of lacquer t water was overkill, my lacquer was over thinned and as a result was either all but evaporating or completely soaking in to the wood.

I had to take it back to the beginning for the clear coats. All the coats I had done so far were basically useless. I tried shooting straight lacquer, as someone at OLF suggested, but it wouldn't shoot. Even with the air pressure cranked right up and the spray pattern as narrow and strong as it could be, it barely came out of the gun. Not surprising really, it's winter here and the temperature is not ideal for spraying.

I mixed a new batch, this time at 8:1, a much thicker ratio than before. This time, with a little playing with the settings on my compressor and gun I was able to get a nice spray pattern. My passes had to be a bit slower than before, but no biggie!

I also changed my spray schedule, as per advice at OLF. Instead of spraying 1 coat a day, I sprayed 3-4 coats a day with 1 hour intervals, over a few days. After 7 coats, I took it down and gave it a rough sand. Finally, white residue! That meant the lacquer was finally building. I sprayed another couple of coats, left it a day to dry, and then started sanding. I sanded at 400, 600 and 800 grit. I didn't get it back to perfectly smooth, even after hours of sanding, but it was a lot closer than before I started.

Now I've sprayed 2 more coats, and left them to dry. And that's it! I could probably have given it a couple more coats, but I think it will be fine. I'll give it at least 3 weeks from today before I start wet sanding. I'm hopeful I can go straight to 1000 or 1200 grit with wet sanding, but I think that might end up being ambitious. But we'll see!

That's it for now. See you in about a month!

Grand Angus Project, Part 5: Progress, progress, progress

Well, quite a bit has been happening since my last post! After posting it, I did a recheck of my lacquer levels and realised I had overestimated my stock. Bugger. It meant I had to reassess me next steps, because I didn't have enough to do a full coat; only enough to do some touch ups.

I did what I could, and if I'm honest I think it was a mistake to add any more colour. It was looking pretty good, and the extra coat darkened it (obviously) and I think I overdid a few spots that I think will show up at the end as overcooked.

Still, it was done! The last thing I needed to do before doing the clear lacquer was to paint the front of the headstock black. I taped up the edges of the headstock with masking tape. Made a bit of a boo-boo here, when I didn't tape up the back of the peg holes. I didn't think ahead that paint might run through the peg head to the back of the headstock! I know, idiot... I realised soon enough and taped over the back of the peg holes.

I initially planned to use my old hobby spray gun to paint the face, but it was still playing up. I felt the big gun was overkill, and would end up wasting a bit too much of my limited black paint, so I decided to go old school and went with a brush.

It came out reasonably well. I tried to do it thick enough that I could get away with only applying the 1 coat. Once it was dry I set about sanding it back to smooth.

By the time it was close to smooth I'd opened up a few spots where I had sanded right through the coat. Whoops! Still, not surprising after only 1 coat. Again, I went the shortcut route of trying to patch the spots rather than apply a whole new coat. That ended up being a waste of time, because when I went to sand the touch ups back I opened up some new spots! So I added a whole new coat, then.

That did the trick. I made a bit more of a conscious effort to make that coat as smooth as I could, to simplify the sanding process after and minimise runs or bulges. I also wet sanded this time, rather than dry sand like the last couple of coats. It came out fairly smooth. Smooth enough!

That was it! That was the last piece of colour to go on this guitar! That was a pretty exciting moment. First thing I had to do after that was remove the masking tape from around the headstock.

Faarrrrk... The tape hadn't entirely done it's job. A bit of paint had seeped under the edges of the tape almost the whole way around, and at 1 point the tape had actually removed a tiny bit of the red finish. In hindsight, and if I had the patience, I probably should have let the red coats cure before taping over them. But that would mean adding 3 week to the schedule. Wasn't very keen on that idea!

I used a fingernail to scrape off the paint that had run under the masking tape. Worked alright, but I scratched a bit in to the red in some points. Unfortunate, but the imperfections are tiny... in this are, anyway!

Still, I had to move on. I'd taken delivery of a huge tub of lacquer. The same as the stuff I used for the coloured coats, but about 5 times as much! Although it was the same product, it seemed quite a bit thicker, and I didn't think it would spray very well as it was. So I used an empty jar to mix a 2-to-1 ratio of lacquer and water, respectively, to thin it.

I needed to spend some time with my spray gun to get the jet right. Until this point, the jet was too strong and the coats were spotting. This is evident in the colour coats, unfortunately, but for the clear that wasn't an option. I opened the jet right up, and sprayed a bit on some scrap wood. It was looking much better.

After that, I was able to spray from about 8-12 inches away, which is how you should be able to spray! I did the front of the guitar and the face/sides of the headstock while holding the guitar in my hand, then hung it up on the rig to do the back.

The photos make it look better than it does, if I'm honest, but I still think it's looking alright! Above you can see where the colour is a bit thin - namely, the middle of the neck - and where it's a bit thick - around the horns. The photos above and to the right show the guitar after the first coat of clear lacquer. Until it dries I won't have a fair idea of how the coat has settled. When it first went on it looked a bit orange peel-ish, but my test piece had that as well and came up - if anything - a bit thin.

Come tomorrow morning I should have a reasonable idea of how it's coming along! Then I'll get another coat of clear on it before running away for the weekend. I'll be back on Monday to do 1 more coat, and then hopefully that will be it!

Once the clear lacquer coats are finished, I'll have to leave it for 3 weeks to cure. That means there won't be many (if any) blog posts for a while. I'll be back when it's cured for final sanding and polishing. Til then, though, thanks for stopping by!

Grand Angus Project, Part 4: It's all about the depth, man...

I've been a bit busy since my last post, painting away. I had a finite amount of lacquer, and I was desperately hoping that I could complete the colour coats with what I had.

You might recall I was having some issues with my little spray gun? Well, I wasn't about to let that get in my way, so I went out and did about the manliest thing that it's possible to do and bought an air compressor and a gravity fed spray gun!

It. Was. Awesome.

I was spraying away furiously, like some sort of spraying machine, adding layers of lacquer in a desperate bid to get the guitar to take on the desired colour. But, as you can see from the image on the right, even after 3 coats the colour just wasn't deepening.

It was obvious that there wasn't enough of the ColorTone stuff in the lacquer. You could see the red/brown of the combined cherry and mahogany reds, but it was way too faint and just not good enough.

It was time to rethink. I'd used between 2/3 and 3/4 of the lacquer, I'd estimated, which meant I would be looking at a maximum of 2 more coats before I ran out. If I wanted to get the colour I was looking for with the lacquer I had left, I was going to have to increase the concentration of the ColorTone. By a lot.

So that's what I did, dammit! You may recall there were about 40 drops of colour in the lacquer before I started? Well, I added about a million. A relatively even spread between the cherry and mahogany reds, maybe a little bias to the mahogany as the original ratio went that way. I added colour until the mix was almost black in the jar. To the left are the before and after shots.

With a better mix of colour I set about getting the first of what would (hopefully) be 2 coats of a better, deeper colour.

Then I hit an issue. The new spray gun, with the fancy compressor, wasn't spraying properly. The spray was sporadic and thin. Clearly there was a blockage somewhere, and my cleaning job after each usage had been inadequate (to say the least).

It took a while, and in testing used quite a bit more lacquer than I would have liked, but after disassembling the whole spray gun I found and cleared the blockage. Obviously, is was some dried lacquer that was deep inside the gun. I did get a coat on to the front of the guitar, though, while I was struggling with it. The results can be seen below.

The coat I got on the front was a tad heavier than I intended, so rather than spin it around and do the back straight away I decided to lay the guitar down on a workbench with the wet side up to minimise the chance of any runs. I think that was a good move, because the coat on the front ended up looking really nice and quite rich.

Whilst the colour that came out wasn't quite as dark a red as I was shooting for, I'm actually quite happy with the shade. The red is a bit deeper than it looks in the picture, but comparing it to the picture above you can tell how much richer it is than before. I think the flame top is showing up quite nicely. I still have no idea if it's actual maple or not...

On the lacquer front, after doing the first side of the guitar I was still going OK; it's starting to look like I might get 2 full coats. I had done the front a couple of days ago, and tonight hung up the guitar to do the back, the sides, and the headstock.

The back is always a bigger job, at least with a set neck, because you have to do the back of the neck as well. At this stage I had cleaned the gun completely, and as a result the lacquer was flowing much stronger and heavier. This wasn't actually very helpful, and the coat ended up being quite heavy, and began to spot as soon as it hit the wood. It was very tricky, because I felt if I stood ay further back the lacquer would dry before hitting the guitar, and even then it was too heavy.

After every few passes of spray I could see spots forming and excess build up, so I used a rag to lightly pat down the lacquer to try and get rid of it. I dabbed lightly, being careful not to actually wipe, and cleaned up what I could. It seemed to work OK. After I had done the whole back, the sides and the headstock, I took the guitar off the painting rig and laid it dry-side-down on the work bench, and used a rag to tidy up the excessively thick bits that were quite spotty.

This presents me with something of a problem. I have enough lacquer left for 1 more coat of colour, but if it goes on as spotty and heavy as this coat I find it unlikely that I could get a very smooth consistent coat. Ideally I would spend some time figuring out the right settings on the gun and the compressor to get a perfect spray, but I don't have the lacquer to spare.

So that's an issue. If you have any suggestions, feel free to leave a comment.

But as you can see, the colour is looking heaps deeper, and is starting to look more like a proper guitar. I'm pretty happy with the depth, and how it's showing through, and if I can get 1 more clean coat before adding the clear I think it's going to look pretty rad.

'Til next time..