Ash's acoustic rabbit hole

[Bizman62]

41 minutes ago, ADFinlayson said:

it was a traditional method for grainfilling and that the oils from the rosewood dyes that pumice powder brown to work as a coloured grainfiller.

Traditional indeed, nothing against that. I just thought that you might easily get wood dust of different species more than you'd ever need.

8 minutes ago, ADFinlayson said:

The lacquer doesn't have a filling properties,

Agreed, not as such. But it builds up faster than plain BLO.

43 minutes ago, henrim said:

Must have been too good or seriously poisonous

Most likely the latter. I'm allergic to "chemical solvents" and at the 4th grade I was freed from woodworking since the painting room spread its fumes all over the basement. Ventilation through the window, an open wide sliding door to the workbench room which was a few steps lower so any heavy gases would sink there. I remember having been in a funny mood when visiting the painting space...

[Prostheta]

A bit of an aside, but "Crimson Finishing Oil" is an grossly overpriced product (or variants of the same product now, it seems) that are simply an analog of Tru-Oil or otherwise cheap BLO cut with a varying fraction of solvent. Get a tin of naphtha (light fluid) and cut your own oil. It's way cheaper, and you can control the flow of the oil throughout your finishing process whether it's for a penetrating flood, bodying or flashing final coats. Work smarter. I buy Tru-Oil 960ml at a time for our Sapele furniture and house fittings and divide it up into jars of 8:1 cut and 4:1 cut.

[Bizman62]

2 hours ago, Prostheta said:

that are simply an analog of Tru-Oil

Exactly that. As a side effect of urbanization people not only lost their country roots, they also lost the know-how of mixing basic elements like BLO and turpentine and a suitable amount of lacquer/poly/varnish/resin for a hard wearing thin finishing product.

As seen above, the resin can have various names depending on what the raw material is and/or where you live.

Which brings me to this question: What is the

2 hours ago, Prostheta said:

naphtha (light fluid)

you talk about? Not the Zippo filling stuff, I guess? Even in the Finnish language there's several names for common solvents and if their labels are multi-language, the mix is even more confusing.

[10pizza]

Following this one for sure as I have a few acoustic bodies that need to be finished by me.

Hat off to you AD, seen a lot of great builds coming by on Instagram.

 

 

[Prostheta]

2 hours ago, Bizman62 said:

Which brings me to this question: What is the naphtha you talk about? Not the Zippo filling stuff, I guess? Even in the Finnish language there's several names for common solvents and if their labels are multi-language, the mix is even more confusing.

Yep. Pretty much just lighter fluid, but check your tin of course. I've seen it called kerosene or lamp fluid. I used some basic "Mustang" junk from Tokmanni last time and it works fine. Behlen also sell VM&P Naphtha ("Varnish Makers & Painters") which gives you more than a clue about its end use in this respect, and you know what you're getting if it's labelled VM&P. We call it nafta, same as a lot of central and eastern European states, however its meaning can be less specific place to place.

The only thing one can say with any level of certainty is that it's terrible for your health. I'm fairly sure that @ADFinlayson will allow me this indulgence mid-thread

 

[Bizman62]

2 hours ago, Prostheta said:

Pretty much just lighter fluid, but check your tin of course. I've seen it called kerosene or lamp fluid. I used some basic "Mustang" junk from Tokmanni last time and it works fine

So really just Zippo stuff, 'sytkäribensaa' (lighter gasoline) which being naphta is different to lamp oil which in turns is purified kerosene, In a lighter there's a difference, as solvent apparently not so much if I understand you correctly.

I've been using pine turpentine for the most part for diluting BLO but during the summer I've used mineral turps as well because I ran out of the coniferous distillate. Somewhere I read that the main reason for not using the mineral based stuff is the lower ignition point which doesn't matter that much in outdoor use.

[Prostheta]

There's a number of different solvents you can use. Tru-Oil uses one called "Stoddard solvent" which is just another name for white/mineral spirits, or Turpentine substitute. The difficulty when choosing the right thing to cut BLO is finding a good solvent, but once you'd done that the product becomes stupidly cheap to mix to specific applications. Tru-Oil is nice because of the consistency, and the fact that BLO is not too cheap "because Finland".

[ADFinlayson]

10 hours ago, 10pizza said:

Following this one for sure as I have a few acoustic bodies that need to be finished by me.

Hat off to you AD, seen a lot of great builds coming by on Instagram.

 

 

Thank you mate

[ADFinlayson]

Well I got a couple of coats of lacquer down on the mahogany build, but I got fed up with the mess and decided to down tools until I could sort out the workshop revamp. 

This is murder corner, full of trip hazards and suffering, and where most of my acoustic related tools and jigs usually live.

Starting with the spray booth. I've got a cupboard in there now where all my dyes, finishes etc live and a bench above so I can do all my paint prep in there with extraction (I used to do it on the table saw with the whiff of thinners lingering for hours)

But the spray booth now looks like a hoarders paradise while I move the rest of the shop around. 

That kitchen cupboard used to be the base for my drill press and pattern-makers vice the other cupboard was one of the wall hanging cupboards from murder corner. This new bench is going to be my assembly/setup/soldering area. With a bit of rejigging, I should be able to get 5 guitars on the wall there with a little bit of tool wall and some under bench storage. My guitar amp will (small head + 1x12) will fit under the tapered corner.

It passed the strength test while I moved the contents of wood rack, I didn't enjoy that bit much, but I did find a couple of nice pieces I'd forgotten about.

And murder corner is looking a lot better (middle aisle by the table saw is still a catastrophe)

Behold, the acoustic workstation. Annoyingly the bending machine doesn't quite fit underneath - I didn't want to make the bench any taller given that I am vertically challenged. But I might get a 9" press screw for it as it's longer than it needs to be.

The workshop looks and feels so much bigger now, can't believe how badly I was using the space before.

Now I just need to sort out the last remaining bench which will be home to the drill press and the bobbin sander here

[Prostheta]

Looks like one could go crazy over a weekend in there and end up with a bunch of unfinished projects

Any problems from those pesky neighbours of yours, still?

[ADFinlayson]

23 minutes ago, Prostheta said:

Looks like one could go crazy over a weekend in there and end up with a bunch of unfinished projects

Any problems from those pesky neighbours of yours, still?

No mate, I moved house in Feb 2021. There are more than a few unfinished projects.

[ADFinlayson]

3rd and final workstation in place. A home for the drill press and a couple of sanders, the little belt sander has never had a permanent residence before but then I only really use it for nut shaping. A good tidy up then back to work.

[Bizman62]

I - want - a - workshop!

That said, despite having tickets to four lotteries weekly I've still paid more than the few wins I've got. But as long as there's a 50% chance to win the main prize there's hope. One day the coin may flip my way.

[ADFinlayson]

6 hours ago, Bizman62 said:

I - want - a - workshop!

That said, despite having tickets to four lotteries weekly I've still paid more than the few wins I've got. But as long as there's a 50% chance to win the main prize there's hope. One day the coin may flip my way.

I'm looking forward to pictures of your snowy workshop. Could you make it out of ice like in Die Another Day? I bet it would be cheaper

[ADFinlayson]

Managed to get the spray booth mack into a serviceable state today and got a couple more coats on. It's had 5 coats in total now. It's very warm in south-east England at the moment, 31º today, 26º in the workshop and very humid so I added a glug of anti bloom thinners in the lacquer, made a huge difference, I'm tempted to use it all the time. This is how it's currently looking, the tortoise shell has really popped.

Happy with how the neck is looking too, although I filled the grain in the rosewood, it clearly needs more lacquer to get the stinger perfectly smooth.

And having fully caught the acoustic bug again, and wanting to play on the my new workbench, I found my next cheapest bit of spruce (German spruce I think) and got it together. Tried out a new technique of clamping, I've always doubted this method, but it clearly does work if the joint is good. 

I'm trying out the method on the Stewmac video for cutting the rosette & channel - In short it's cutting both the rosette and channel at once with a router cutter the same width as the purfling. I cut a couple of slithers off one of my carve top billets that was thicker than it needed to be so I thought I'd do a solid curly maple rosette with the BWB purfling around the edge. It seems to work, I've cut the outside of the rosette and the outer channel so far and test fitted some purfling. It was getting a bit late for dremel so I will finish the cuts tomorrow.

I wiped some lacquer over the spruce before hand to prevent tearout, I tried oil on previous rosette which works too, although I think the lacquer worked better, I will 100% be doing that when it comes to binding too.

lastly one more experiment, I got myself some 8mm steel bar, cut it in half to make heavy duty locator pins that go through the mould. They're offset so it will only work one way which will hopefully prevent me running the risk of putting anything on backwards. Jury is still out on that one!

[ADFinlayson]

I've discovered the alchemy to a half decent looking cherry shader is about 98% brown and only a splash of red, and brown must be added first or it just looks weird.

I gave the whole thing a good scuff sand with 240 - 320 to get it all fairly level, then a coat of clear to cover up the spots I sanded through, then the shader, then another clear to protect the colour. I spent most of this evening scraping the red off the binding and fretboard edge with a razor. These pics are post scraping so it's ready for more clearcoat.

Really happy with how this has come out. 

In other news, I finished the rosette and cut the soundboard for No4, the flame maple came out quite nicely, it's got tight quarter sawn that lines up really well with the spruce. There is a slightly dark area in it too which comes out as a nice little gradient, not planned but I like it. 

The locator pins seem to be working too, it's bang on centre.

 

[komodo]

On 9/5/2023 at 8:02 AM, ADFinlayson said:

This is murder corner, full of trip hazards and suffering,

My whole shop currently.

[ScottR]

On 9/9/2023 at 2:49 PM, komodo said:

My whole shop currently.

I'd add to the LOL icons....but that describes mine as well.

SR

[ADFinlayson]

Haven't managed to get any more spraying done, too damn humid. When I sprayed a couple of coats on Saturday I got a bit of blushing around the heel transition which I managed to rectify yesterday with a combination of heat gun and misting a bit of thinners over it. I think the thinners works best - there is a very fine line between getting the lacquer hot enough and making it blister with a heat gun. 

I have done a bit more on OM No4 though. Rough carved the braces and glued in a bridge plate. It looks a bit lop-sided but it's touching 2 x-braces and the top tone bar so I figured that would be a good thing. The bridge plate is made from 3x 0.5mm thick rosewood veneer glued together with a cross grain laminate in the middle. I glued them together on the dish so it takes on the 28' radius, left it clamped for a good 24 hours to make sure it didn't warp, I think epoxy would be better for this job. 

Got the back cut out and works with my locator pins from the other side. I keep thinking it reminds me of Lord of the Rings, looks like an Ent

Got a back strip glued on, used an offcut from the back, I did that on the last one, I like the stealthy look of using the same wood, even though the grain is going the other way, it's not very visible when looking through the sound hole. The offcut wasn't quite long enough so I will just butt another bit up to it, no one will see it all the way down there anyway.

and I got the side I bent last night out of Bender. I kept it quite thick at 2.5mm (I think that's considered very thick for sides) but I thinned down the waste area to 2.1mm so it seamed to bend very easily (touch wood) I think Korina just bends nicely. But I don't want to jinx it because the other side is in Bender now.

I'm bending the sides at 120ºC (at least that is what the dial says), just a mist of water the wood before wrapping it in foil. Getting it up to temp before doing any bending, then leaving the blanket on for 10 mins after bend. Then an hour later when it's cold, turning the bender back on for 10 mines - the idea being that it will help remove any more moister that might still be in there. 

My springs are pitiful so helped it along with a load of elastic bands.

 

 

[ScottR]

14 hours ago, ADFinlayson said:

I keep thinking it reminds me of Lord of the Rings, looks like an Ent

It sooo does! One of the younger ones.

SR

[Prostheta]

So in principle you are saying that wood looks like a tree? 

[Bizman62]

1 hour ago, Prostheta said:

wood looks like a tree

That sounds funnier in Finnish: Puu näyttää puulta...

[ShatnersBassoon]

When you start building acoustics, it’s serious business! Will be following this one closely Ash!

[ScottR]

22 hours ago, Prostheta said:

So in principle you are saying that wood looks like a tree? 

It sounds so profound when you put it like that.

SR

[Prostheta]

1 hour ago, ScottR said:

It sounds so profound when you put it like that.

SR

 

Blessed are the cheesemakers!