Acacia dread build thread

[56nortondomy]

The epoxy has really made the b/wood pop Allan, should look awesome under the finish. Wayne

[demonx]

This morning is a day off, so I spent a bit of time 320 sanding the entire guitar, running the 320 around all the shard edges to create a minor fillet and just paying attention to anything I may have missed.

Problem areas I place a bit of tape to find them easily (less sanding work later involved than if I used pencil) and then I come back and do some touch up fill or whatever is needed.

In today’s case, there was a spot on the rear binding which needed a tiny bit of fill, as seen in this pic.

There was a pinhole in the Gidgee headstock cap which I filled and a couple of spots around the edge binding. Once these are dry and sanded, the guitar is then ready (I hope, unless I missed something) for spraying the sealer.

[demonx]

Spraying!

In the time I’ve been on this forum I see a lot of newcomers as well as those with a few builds under their belt asking about spraying, so I’ll break down the process with some hints and tips to help you experiment and learn your own way.


- I use Nitrile gloves. Latex gloves will just melt off your hand if using 2k. Make sure to at the absolute minimum wear a canister mask which you cannot smell anything through. If you rarely use it then it’s probably best to use a fresh canister each time. These should be kept inside an airtight container when it in use so air doesn’t flow through the canister.

- airhose away all dust a considerable amount of time before you spray, so that it has time to settle. A lot of dust comes from the floor, so be aware of this. Before your guitar is in there too!

- one tip from booth painters is to spray the booth with insect spray as to eliminate and flying pests which may want to land in your wet paint. Again, allow time for that to settle as well and do it before you hang your guitar.

- Make sure to always empty the air/oil traps on your compressor and to make sure you dump the water out of the tank.

- mix your clear coat and set it aside to start its process, then prepare your gun. I like a 1.8mm tip when spraying clear coat. I use the same tip for clear sealer and any solid primers. I use 1.4mm tip if I’m spraying base coats, but for this guitar the only tip used will be 1.8mm.

- set the air pressure AT THE GUN! I like no less than 40ish when spraying clear. Too many beginners use the gauge on their compressor. This is not going to give you an”at the gun” pressure. Too many beginners are scared of the air pressure and wind their guns screws in too far. I’ve never had mine in further than half way, even that is too much.

- It’s called spray painting, not splash painting, if you don’t have enough air pressure the paint will “fall” out of the gun into the guitar and not spray onto the guitar and atomise etc as the products are designed. So have that air pressure at the gun, if you don’t have a gauge on your gun, buy one! Also make sure you aren’t holding the gun too far away as this will cause another issue of the paint drying too much before it gets to flow on the surface. 10-15 cm is a rough comfort zone. Much further away than this is too far and the paint can’t work As it’s designed.

- The first coat you spray you will move a bit quicker so that you’re not laying on too much, you’re not looking for total coverage on the first coat, you’re looking for a base to work from. This is called tack coat. By get a quick, thin tack coat on you lessen your chances of creating a run as it’ll help the following coats adhere and stay.

- Crossover between coats is a personal choice, I’m a lazy sprayer and tend to do about 50%, somesprayeds will feel safer and more comfortable around 10%. The more crossover the more chance of a run, but you’ll get better product flow as well with a bit more crossover. So choose according to your skill level and comfort zone.

- Flash time (time between coats) is a variable according to environmental spray condistions, so let’s assume you’re spraying in a garage and not a professional booth, like I am spraying in a garage in these pics, I like to leave 10-15min after the tack coat. Then I’ll spray the second coat, wait around 20-30 min, then around 30 minutes before I spray the third, if I’m spraying a fourth I’ll leave it 30-45 minutes.

The reason for this is, if you spray too close together and not allow it to flash off, then you will trap gasses inside the finish, you’ll get solvent pops, fish eyes, more chance of runs and hangers. So it’s better to leave it that little bit longer when you’re not inside a booth.

- One tip that isn’t always done, when you’ve finished your spray session, let it tack off again for an extra extended time and then peel back the fingerboard tape. I don’t always do this, but sometimes paint can chip at the edge around this area and if you peel it back while the tape is just tacky, then you eliminate the chipping issue.

[demonx]

I’m hoping this links works, it’s an example of my lazy spraying, but it gets the job done.

https://www.instagram.com/p/BrjMkPQHRvv ... c3ytm987uy

[Mat]

Great explanation on the spraying, its an area I struggle with and my old man is a qualified french polisher and furniture sprayer pushing 67 years of age. Maybe I should just ask for a lesson.

and that timber looks great!

[kiwigeo]

What's that gun youre using?

[demonx]

What's that gun youre using?

It’s actually the cheapest piece of crap gun that I’ve got!
A $100 workquip !!!

It’s my primer gun, but since ive broken all the cups for my other guns and not putting money back into the business I’ve just been using this for everything lately.

[demonx]

This one has been put aside for quite a while, however with today being the perfect temperature for spraying I thought I’d take the chance to lay down some more sealer coats.

It had three coats last time and then I’d sanding it back to the timber, not planned that way, it’s just that I got some rub throughs and decided to do a full sand back. Today I’ve sprayed four more coats.

[WJ Guitars]

The timber grain is looking great. How many more coats will be applied for the final finish?

Wayne
https://wjguitars.wixsite.com/mysite-1

[demonx]

The timber grain is looking great. How many more coats will be applied for the final finish?

Wayne
https://wjguitars.wixsite.com/mysite-1

It depends if it sands smooth this time or not, if not then it’ll get a few more coats of sealer, if it stands flat then it’ll move to clear coats where I usually do three.

[demonx]

Block sanding the sealer wit 320 grit followed by a buzz over using 600 grit on a random orbital to remove the scratches.

Had a few killer hangs/runs in the sealer as I laid in on thick last time, good thing it stands out so easy! I’m not stressed about getting runs when a spray primer/sealer. If it happens it happens, but it’s not like I aim to get them either. It’s not like the top coats or colour coats where it’s more of a problem if you have runs.

This one is now ready for clear top coats, once the weather is a bit more suitable. 40+ degrees in the workshop today is not spraying conditions!

[demonx]

This morning I shot three coats of Mirotone 2k clear onto this one.

Now that I’m spraying clear and not just sealer, I’m more particular on my spraying as I have the build already in the sealer, now I’m looking for nice smooth glossy coats, not so much thick coats.

I’m moving faster now that I’m spraying top coats as I don’t want it thick, I want it smooth, so I want it only just thick enough to flow nicely but not run or hang, I’m more particular on my crossover for the same reason as I don’t want too much built and I’m careful on my flash time as I don’t want to be too fast that I get solvent pops and I don’t want to be too slow and have it too dry between layers, so my flash times were 10 mins, 20 min and 30 minutes. The temperature in the workshop today is low 20’s.

Hopefully these three are the only clear coats I have to spray and the next step will be cut and polish. But you never know with this type of work.

[demonx]

Polishing:

This link shows the speed that I polish at. Any faster is too fast. The guy I learned to polish from goes even slower than this, but his paint jobs are also better than anyone else I know.

The clear was cut first with 1000, then 2000, then 3000.

I’m using 3M Perfect it polish on a 3M blue waffle.

https://www.instagram.com/p/BtUb9vnHjuf ... fwb9ybqmt8

I only polished the top today as I didn’t have much time. The rest I’ll work on in stages next week in between other jobs.

[kiwigeo]

Thanks for the updates Allan..all looking good

[demonx]

First string up and a quick strum. I cut the nut to 0.5mm and pulled the relief back a bit so it was slightly playable.

https://www.instagram.com/p/Bte1KBjnZAe ... 50rckt1q6j

Now to let it sit for a few days under tension, maybe a week before it gets a proper setup.

[kiwigeo]

Nice big dreadie sound!!

[demonx]

Nice big dreadie sound!!

Until it’s set up I won’t be able to give it a fair evaluation as the strings are miles above the board at the moment, but from what I can tell id say it has a great sound, as expected it needs to be attacked a bit harder to get the top moving but that goes for any hardwood topped guitar.

I’ll know more in a few days once I do the saddle height and relief etc and make it more playable.

[vandenboom]

Hi Allan, only just read this thread for 1st time. I have never tried a hardwood top and have never explored it. I was struck by the 3.5mm target top thickness given in your nov 7 post. Most spruce tops are around 3.0mm. Why would a presumably q/sawn hardwood top be more than that? Curious.
Frank

[demonx]

Hi Allan, only just read this thread for 1st time. I have never tried a hardwood top and have never explored it. I was struck by the 3.5mm target top thickness given in your nov 7 post. Most spruce tops are around 3.0mm. Why would a presumably q/sawn hardwood top be more than that? Curious.
Frank

Simple answer, I don’t do 3mm tops in any timber. I have in the past and then later had to add thickness as it wasn’t good enough.

More complex answer, it also depends on everything else as there’s so many variables, so building the way I build will be different top thickness to the way the next person builds as the rest of the recipe will change as well. When I’ve gone down as low as 3mm, especially in Cedar it’s been too boomy for my tastes, that half a millimeter is the difference between near perfection and a boomy guitar. I only learned this after several builds, then going back and changing things on certain builds. For example one 3mm build had boominess that I was able to fix by making a heavier bridge and I also sprayed new layers of clear on top to try thicken it up that way also, then I rebuilt the same specs in the next guitar with a consecutive cut top, added thickness to the top and back to a lighter bridge and the boom is gone and the sound is golden.

[demonx]

I finally got around to taking finished photos:

BF0AB11A-7CBB-42BF-A804-AD01AEF8CCE2.jpeg (144.56 KiB) Viewed 861769 times

[WJ Guitars]

The guitar looks amazing Allen! Beautiful timber combination styling and wonderful character. Now that the guitar is more settled in with the new strings do you have any more recent sound samples available. It be great to hear a sample of this guitar.

Wayne
https://wjguitars.wixsite.com/mysite-1

[kiwigeo]

Nice work Allan.....a real eye candy job.

[demonx]

The guitar looks amazing Allen! Beautiful timber combination styling and wonderful character. Now that the guitar is more settled in with the new strings do you have any more recent sound samples available. It be great to hear a sample of this guitar.

Wayne
https://wjguitars.wixsite.com/mysite-1

Thanks Wayne

I’ll be honest, it sounds better than I expected, I took a risk using the Blackwood and I’m glad to say it didn’t bite me in the butt!

As far as sound samples, I only have a mobile phone to record with, so I may as well be playing a banjo

[demonx]

Nice work Allan.....a real eye candy job.

Thank you!

[56nortondomy]

Looks great Allan, they're two of the nicest looking timbers we're lucky enough to be able to use and you've done them justice. Is it a keeper?
Wayne