Ebony dust (Full Version)

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mango -> Ebony dust (Feb. 26 2021 19:26:11)

During my second built I decided to work more clean because last time all the dust from adjusting the fretboard went into the fibers of my soundboard... so this time I made a fancy cover out of very thin mdf and gave the soundboard a coat of shellack to protect it from the dust. But now it seems to be even worse because the black powder goes through all little gaps underneath the mdf plate and now has been rubbed into the soundboard by the cover :-/ now I think next time I make the soundboard 0,5mm thicker and just sand everything off after the black dust is gone... how are you guys handling this problem?




RobF -> RE: Ebony dust (Feb. 26 2021 21:32:29)

It never hurts to leave a bit of wiggle room for cleanup, but half a mm thicker to allow for sanding is HUGE, lol. Maybe leaving 0.1mm extra is prudent, 0.2mm tops, and there’s many who would say that’s way too much.* It’s also probably better to save the wiggle room for addressing unforeseen catastrophes, rather than for general clean-up tasks.

The only real mis-step you made was to handle the area being protected by the cover, because it was giving you a false sense of security. Everything else was on the right track.

Giving the top a spit coat is good. A reusable slip cover can be made from semi-stiff plastic with a felt backing (better than thin MDF, which is likely too stiff). Lots of makers just tape on poster paper cut to the shape of the upper bout with a cutout for the fingerboard that can slip into the soundhole and then underneath it.

Main thing is don’t touch the covered area of the guitar while working. Brace the tail end of the guitar against something that has a non abrasive covering with the covered head braced into your stomach and work the neck that way, or clamp the guitar in a cradle and then to the bench, whatever works; just don’t hold the guitar at or push down on any area that has a protective covering over it as any detritus that has found its way underneath can then be ground into the (supposedly protected) surface.

I keep a couple of high quality soft bristle paint brushes at the bench and use them to brush off dust (they’re good ones normally used for house painting, I think one is 3 1/2” wide and the other is a pointed blunt end one with bristles bunched into a bundle about an inch in diameter). Brushing off with your hand can push dust/detritus into the top and should be avoided. I also use a vacuum, but only to suck dust off the protective covering over the sound hole and off the fingerboard itself. I grasp the nozzle firmly in my hand and brace it a short distance from the surface with my fingertips to keep the nozzle from being sucked down and hitting anything.

Blowing with compressed air isn’t a good idea as you’ll get ebony dust over absolutely everything. If you use your mouth it’ll just blow back into your face.

Saving some of the ebony dust in a jar for future use is always a good idea, as it can be used to fill tear out.

I think I might start a thread asking makers to show off their work spaces, as a huge amount can be learned from those pictures. Whenever someone posts a picture of a new guitar I’m always looking past it to see what’s going on with their bench and in the room behind, lol. There’s always something to learn.


* For a point of reference, measure the thickness of a cutoff before and after removing the scratches made by an 80 grit paper by sanding down to a fine finish. The difference is probably plenty to leave as wiggle room.




ernandez R -> RE: Ebony dust (Feb. 27 2021 1:02:25)

I always look behind the guitAr to the workbench or whatever ;)

It’s all about dust control. I have two larg shop vacs outside the shop in a shed , was one but I had a productive minion so we added one, the hose and power cord com through the wall and I’ve got a switchable power strip there to turn them off and on. I’ve got enough hose to get to the shop shop.
Couple things: shop vacs throw dust everywhere and the dust they bypass even with the best filter is the kind that does the most damage. Also having them outside makes for a piecful shop.

Now my main bench has a little down draft section that I plug the hose in, nice when fitting saddles and bridges, sucks up CA or other fumes, It’s just handy. And nothing more handy then a little battery hand vac although the air bypassed can blow dust around, super handy for chips and what not or clearing sandpaper from bridge and saddle bone; I reach for mine ten or twenty times a day.

Another thing about the shop vac outside, when I need max performance, I resawwd a bunch of Camphor wood last year, I just pull the filters and let her run commando!





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Andy Culpepper -> RE: Ebony dust (Feb. 27 2021 3:18:02)

I mask off the upper bout of the top with "delicate surface" painter's tape when I'm working on the fingerboard.




Stephen Eden -> RE: Ebony dust (Feb. 27 2021 9:21:53)

I don't get ebony dust stuck on the sound board and don't use anything to protect it either.

I sand the top to 240grit before gluing the fingerboard. After planing I sand with 120 to 320 and use a vacuum cleaner to remove dust inbetween each grit. including all dust in the sound hole. Good advice about not touching it though.

Once ready to finish the sound board in that area, use a fresh sheet of paper on a block and sand in one direction only. Start in the middle and sand straight towards the rosette and then towards the head, making sure to clean the paper of all dark dust inbetween each pass. This also helps prevent dust from the bindings and rosette to get impregnated into the sound board too.




estebanana -> RE: Ebony dust (Feb. 27 2021 14:30:44)

Eden had the system down, vacuum up ebony dust and shavings as you work. A few passes with plane, scraper or sandpaper and then fly the vacuum over the work. Then learn to sand from the center to the edges so you are not dragging and pushing dark dust and driving it into the top. Think at a smaller level, Imagine yourself living right down on the top surface like you are 3mm tall and you are looking at this like a geologist.

But do it without drugs.




RobF -> RE: Ebony dust (Feb. 27 2021 16:17:12)

I’ll sometimes polish the top before gluing on the fretboard so the method used by the two Stephen’s wouldn’t always fit for me, but I think this thread shows there’s always more than one way to skin the proverbial cat. Also shows you never really were very far off to start with, and all your ideas have merit. It’s just down to care in execution and you’re good.

Don’t forget to keep posting updates as you continue with your project. It‘s fun to follow these.




mango -> RE: Ebony dust (Mar. 6 2021 10:06:25)

Thank you guys! That helps a lot...
Looks like I will be able to sand it out. Nearly finished this second built. A negra with a couple of changes to the first one... Thinner sides, a third harmonic bar like my old Yairi Blanca, heel followes the fretboard until the upper harmonic bar... slightly different bracing (2nd and 6th brace not straight anymore). Having fun to try out things :-)



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mango -> RE: Ebony dust (Mar. 18 2021 9:15:22)

Hey Guys!
I was able to clean the soundboard were well... so all good.
I am currently in the process of French polishing. I made some basic coats during three days... then after 24hrs of drying I started the grain filling with pumice powder. Worked good, but of course the shellac shrinks and now the grain is visible again... one question:

- Do I have to repeat the grain filling step until everything is totally flat and blank or is that just about building up and sanding a bit in between?

Another question... I see some dark spots in the wood. Is that just the structure of the wood? Or maybe some oil that went into the wood? After the grain filling I started to use a bit of oil... or just the shellack which has some high spots?





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RobF -> RE: Ebony dust (Mar. 18 2021 16:37:32)

Hi Mango,

I think you’re doing great work! If that’s your second guitar you should be very proud.

Pore filling is my least favorite job and whenever I hear someone say they get it all done perfectly in four hours or the like, man, do I ever get jealous, because I’ve never been able to pull that one off.

What I can see in the pictures is the pores aren’t filled. I suspect one reason is because there’s way too much shellac laid down. The dark spots are quite likely oil darkened pumice patches. These can be sanded out or removed by attacking the area with an alcohol soaked fad. I have to stress here, and this is important, pumice is an abrasive. Any area you clean up by rubbing aggressively is being sanded and will divot. So probably better to sand it out using a block, but you’ll have to sand the whole back, just sanding the dark spots will end up with an uneven surface. It sounds like starting over, but it isn’t, really.

I’ve started using a hard felt pad for pore filling. I started doing this because a fad can act like sanding by using your fingers over paper, while the pad acts like a sanding block and is less inclined to divot. Using a felt pad is also muy tradicional, if you read old furniture making tomes.

Pumice should be cleared with alcohol only, then applied. At the early stages, even if it’s being applied over an existing shellac finish, the clearing should be done with alcohol. I will use oil to clear, but only if I think pumice is needed during the later stages of polishing, then I don’t use alcohol.

But you’re not there yet. I think you should give a light sanding just until you reached bare wood, give it a couple of wash coats of thinned shellac, then pore fill with alcohol and pumice. Rub with the grain, not against. That last point is counter-intuitive, but my experience has shown it does seem to work better.

As far as letting the shellac pore fill, I’ve done this and it works. Six months later the shellac will shrink and the pores will again be exposed. But this is not necessarily a bad thing as the pores will have a protective layer of shellac on them, it’s not unprotected wood. It can also be very attractive and shouldn’t be thought of as an error or faux pas. But for the glassy smooth finish, the better the pore filling at the beginning of the job, the easier the rest of the job will go.

This is a complicated subject and there are many opinions on the right and wrong ways to do things. What might work well for one person is disasterous for another, so hopefully others will weigh in. I’ve been polishing for quite some time now and I do achieve professional results, but I’m constantly revising my methods, because when it comes to pore filling....aarrrrrrghhhh!

Best,




ernandez R -> RE: Ebony dust (Mar. 19 2021 1:14:31)

She is looking so nice!

I’ve not played with the dark wood with big pores to fill but I’ve just tackled five backs at once and was able to take my polish to the next level. On the backs.

First I found I had to take scrupulous care to not introduce any scratches with foreign objects. Once I had a piece of beard trimming from the morning fall and get under my manuca and cause some heartache.

I’ve got a small block, long edges rounded, ends left sharp and square for getting next to bridges and fretboards, about 1.75” x .75” with three layers of paper towel taped to it nicely. I use 400 & 600 wet dry with this to get down and dirty with some early leveling. Naphtha for lube.

Real important thing I figured out, only and I mean ¡ONLY! sand with the grain in perfectly straight lines. You’ll thank me later.

Once I get to the point I don’t need the 400 and 600 usually day 3 or 4, I use 1000 & 2000 but the kind on those sponge pads only I slice them down the middle, then into quarters, then I debure the edges of the pad with a belt sander until the paper has a feathered edge. I feel a little of my ugly scratched came from the raw edges of the paper.

I start each session/day by carefully cleaning any oil and debris with naphtha and again only straight lines with the grain. Once it is clean and dry I level with the paper using naphtha as a lubricant, I’m not looking for perfect, just knocking the high spots and and red also taking most of the tops of any ridges from the manuca sessions the day before.

I put the thin capalary whip tips from my CA kit onto my alcohol and shellac bottles cause I find keeping strict count of how I charge my manuca critical. Mine is small, less then an inch square four layers of thick wool, double covered with Cotten y shirt.

I lay on three layers then it starts to feels soft and sticky, this is that zen thing... one pass too many and the manuca digs in; ouch. Straight Lines Only!

I put her away for about 30-45 min then I do one pass vary dry with oil. I tamp my manuca on a paper towel until it is dry and doesn’t transfer liquid, then three drops shellac, one alcohol, then one fat drop oil on a board to mix it in first then I pull the manuca flattening any ridges doing a 50% over coat. JUST ONE TIME.! It will drag so don’t stop...

Now, I’ve gone over the backs about an hour later with my hand, rubbing until my hand feels warm and been able to flatten/level of some more. Super zen!

I put her away for the next day.

I make a chart with check boxes and all the steps, how many drops of what, which sand paper and when, timing, any step in the process, actuality all steps.

I’m still battling the tops... but compleatef two of them the other night. I still get a little wonky around the bridge but I’m doing two of the parlors without the bridge, one taped off and one without. I found the tape causing issues early on so I pulled one off to see. I used a couple layers of tape and that was a bad idea as the variing thickness caused issues on the edge of the tape.

Had to get medivle with some outside chores and plumbing so now I’m on the couch foot up trying to make it happy and thumb typing in a iDevice. Fun times!

Remember, I am vary new to this so take what I’m writing with a grain or two of salt.

Rob, what’s your take on using Naphtha as a sanding lube?

HR




RobF -> RE: Ebony dust (Mar. 19 2021 1:31:26)

quote:

Rob, what’s your take on using Naphtha as a sanding lube?

I’ve never actually tried that. I use Naphtha for wipe downs, but I try to be judicious because it’s pretty toxic.

For the longest time I was using Micromesh, most often dry, but also with slightly soapy water as lube. That stuff is quite spendy, so I switched to this Japanese automotive stuff called Super Assilex ( I might have to come back and change this if I see I got the name wrong, I’ve not been in the shop yet this year, but I think next week I’ll get back at it). It’s also pricey but I think it’s a little cheaper. I bought boxes covering the full range of grits and I suspect it’s going to last me a long time, maybe 25-30 guitars, before I’ll need to buy more. Some guys on here, that’s not necessarily that long a time, lol.

I use it dry. I prefer it because it cuts very fast and evenly. I think it was estebanana that introduced it to the Foro quite a few years ago. It’s good stuff.




mango -> RE: Ebony dust (Mar. 19 2021 23:09:33)

Thank you guys! It's very interesting to read your different approaches to this topic. It seems that french polishing is something where everyone finds their own skills and ideas how to reach the glossy goal... yes this is my second build, but my first experience with rosewood pore filling... finally I scratched the shellack off the back again and gave it a second try. Looks much better now. I guess I used too much pressure before... when I rubbed around with the pumice. Rob, what do you mean by clearing the Pumice with alcohol before applying? I just put some dry powder on the surface as I saw it in Pablo Requenas video...





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RobF -> RE: Ebony dust (Mar. 20 2021 0:15:21)

quote:

Rob, what do you mean by clearing the Pumice with alcohol before applying? I just put some dry powder on the surface as I saw it in Pablo Requenas video...

Applying the pumice directly to the surface with a pounce or salt shaker is done, but I’ve never used that method, in part because of how I was taught.

By clearing I mean the pumice is added to the pore-filling fad and then dampened with either alcohol or oil and gently rubbed into the fad with a fingertip until it becomes “clear” by being saturated with the liquid. I was taught never to add dry powder to the surface, but clearly the technique works for some and is valid.

Couple of words about the pumice. I use a mix of 2F and 4F, except if I’m doing a spot fill on an already bodied surface. Then I’ll use 4F, generally cleared with oil, sometimes alcohol - it’s a judgement call. Also, depending on the wood, I often will use pigment to color the pumice. The theory is that this should be unnecessary, and in many cases I’m pretty sure it can be, as the alcohol also pulls the colour from the Rosewood and thus tints the pumice naturally. The problem with this is it only will happen on the first applications as eventually the tint is either all pulled from the wood or sealed into the wood and subsequent applications of pumice will not take on the color. Also, some woods just don’t have the level of stain/tint/pigment/whatever-it-is as rosewood, so there isn’t a lot there to tint the pumice, to start with.

But, as I said, I’m constantly revising. I take longer to French Polish than I’d like. When I started out I could do a passable job on a guitar in a couple of days to a week. I don’t know what happened, but I’ve devolved over the years and now I can easily complete the woodworking portion of the guitar in way less time than it will take me to French Polish it. It takes me close to a month now for polish, granted it’s only an hour or so’s worth of work a day, but it really should take half that time. I wish I lived in Spain, where guitars can be handed off to pros for the finish work. Some of the guys in Madrid are pretty near untouchable with respect to guitar finishing, they come from generations of specialists.

P.S. Just an aside, and I know I’ve already said this, but you’re doing really nice work. Olé!




ernandez R -> RE: Ebony dust (Mar. 20 2021 4:57:55)

Mango,
That is looking really good!

Ya, seems everyone has their way with shellac, or building in general. I like the challenge and conquering but I don’t like the setbacks and frustration. The two Flamenco I just finished polishing were ready to polish this time last year... I’ll give them a couple weeks to really harden then I’ll give them a couple coats of wax and get some strings on them!

Digging your green purfling on this one, couple closeups would be cool if you have a chance.


HR




mango -> RE: Ebony dust (Mar. 20 2021 22:20:52)

Thank you for your kind words! Overall I am pretty happy with this second guitar so far. I also played it a bit before finishing and it is very promising... loud, clear trebles and a strong bass without any boomyness... Unfortunately during these very cold days in February two cracks appeared in the top just when I was about to close the box. The humidity just dropped under 40% very quickly. I fixed them but there are still visible... well, its ok because I don't want to sell the guitar and it actually performs great, but I still don't know how to manage the humidity in my workshop really good. It's in the cellar. I have a heater and fans... Between 05-15° C outside it is perfecty balanced between 40-60%. But in the summer when it's above 20°C the humidity goes up to 60-70% and in the winder it can become very dry when it's cold outside... any ideas?

Well for now the plan is to give it a few more coats of shellack, then let it dry for three days so that I can sand it lightly with 1000 grid. And finally some last coats with thin shellack... sounds good?





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ernandez R -> RE: Ebony dust (Mar. 21 2021 4:01:40)

Photo of my shop water feature.
Just an old stock pot with a water pump, didn’t cost much via Amazon.

I keep it in front of the heater. I’ve got a wood grain hydrometer to keep a general idea about the humidity in the shop, you don’t need decimal points just something to glance at that says, hay it’s getting dry in here! Shop floor is concrest so I’ll toss a few liters of water on it if it’s bad. Drugs out quick if I’m not out there for a day.

HR





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constructordeguitarras -> RE: Ebony dust (Mar. 21 2021 21:45:14)

I use a good shop vacuum cleaner with a brush on the end of the hose and clean up ebony dust on and around the guitar between each grit of sandpaper that I use. It works.




constructordeguitarras -> RE: Ebony dust (Mar. 21 2021 21:49:34)

quote:

Couple things: shop vacs throw dust everywhere

My ShopVacs have cylindrical filters around the motors, but they also accept filter bags to accept all the debris that are sucked up. I find that with both in place, they don't throw any dust around. I only use a ShopVac without the bag when I'm vacuuming up water, as sometimes happens after heavy rains.




RobF -> RE: Ebony dust (Mar. 22 2021 0:20:26)

quote:

My ShopVacs have cylindrical filters around the motors, but they also accept filter bags to accept all the debris that are sucked up.

I bolted one of those bucket/mini-cyclone rigs to my shop vac and put a hepa filter into the shop vac. The only thing that makes it past the cyclone is the very fine dust, which is caught by the hepa filter.

I have two hepa filters and swap them when I empty the bucket. I clean the dirty one first by banging it against a post outside, then running it under the tap or hosing it clean, and put it aside for the next bucket emptying. Works well, no noticeable dust gets blown out the vac’s exhaust.




ernandez R -> RE: Ebony dust (Mar. 23 2021 8:06:14)

That’s funny cause I’ve seen one of those bucket cyclone things collecting dust in one of our outbuildings and wondered if they worked? Thinking I could use one that fits on a 55 gallon barrel, roll it out in the yard and burn it, not uncommon up here in AK.


I resaw from logs and make a lot of chips and dust, both my table and chop saw need new blades so they are making more dust but stretching them out u tip I get paid for my next guitar.

Another reason I keep the shop vacs outside is the blowing they do on the discharge side always seemed to find a pile of sawdust whilst ones back was turned and just spread it around the shop, could be I’m just messy ;) I sure like the quiet though...

HR




RobF -> RE: Ebony dust (Mar. 23 2021 16:43:03)

quote:

That’s funny cause I’ve seen one of those bucket cyclone things collecting dust in one of our outbuildings and wondered if they worked? Thinking I could use one that fits on a 55 gallon barrel, roll it out in the yard and burn it, not uncommon up here in AK.

They definitely work.

In keeping with our philosophy of a picture being worth 1000 words, here you go...Note that the level of dust in the Vac canister won’t get much more than that, even as the bucket fills (matter of fact, that’s probably multiple bucket’s worth). The nice thing about it is the Hepa filter doesn’t clog, generally it’s due for a cleaning right about the same time as the bucket needs emptying, but it’s never really heavily loaded. This allows the vac to also spin freely and suction doesn’t get reduced as the bucket fills.

All in all, it’s a great system for the small shop.





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JasonM -> RE: Ebony dust (Mar. 24 2021 14:47:35)

Wow Mango, it looks really nice! Your work looks so clean for only a number two. Congratulations sir!

Thanks for the suggestion on the cyclone and Hepa filter. My basement where I work is sealed off with no windows. So I put in a 4 inch vent ductf that vents to the outside and hooked it to an exhaust fan. Blows all the fine stuff outside and makes a huge wind rushing noise heard from the outside. My neighbor heard it one day and said, what the heck is that?. I said “No need for alarm, miss...just normal sounds from a meth lab!”




Andy Culpepper -> RE: Ebony dust (Mar. 26 2021 3:12:50)

Looks fantastic, mango. I also love the jumbo-ish frets! (unless my eyes are deceiving me) Far too many people are intimidated by taller fretwire, which is just strictly better in my book.




JasonM -> RE: Ebony dust (Mar. 26 2021 19:03:02)

What do you like about jumbo wire? I don’t think I’ve ever tried it but I’d really like to!




mango -> RE: Ebony dust (Mar. 26 2021 20:12:46)

Thank you! For me taller frets work better if I want to play more lyrical. Things like vibrato are just more easy when there is less contact of the finger with the fretboard. I think many flamenco players like small frets because percussive playing feels a bit more safe... no sliding of the strings on the frets. The string is more fixed on the fingerboard because the finger has more pressure on the wood. I guess it's a matter of taste. On the other hand bigger frets leave also more room for adjustments if the neck is bent after some time for example.




Andy Culpepper -> RE: Ebony dust (Mar. 27 2021 3:36:56)

Same reasons for me, I like the left hand feel better and the room for future adjustment. Building a flamenco guitar with a scalloped fingerboard taught me a lot about the possibilities of more room under the strings.




ernandez R -> RE: Ebony dust (Mar. 27 2021 6:22:28)

I too am a fan of the fatty frets!

Easy on my old hands to fret

Super easy to install, get the straight lengths of course.

I don’t have the exact numbers handy but I use tha Jascar EVO Good and SS accordingly.

Was thinking I need to do a couple standard sized frets just to be sure as my playing has improved the last couple years, now I’m only bad instead of terribly bad ;)

And of course Andy for the win noticing this, I was too distracted by how good the green looked in the perfling and the rosette overall.

HR




mango -> RE: Ebony dust (Jun. 3 2021 12:19:01)

Finished this one...

How do you like the sound?





JasonM -> RE: Ebony dust (Jun. 3 2021 14:33:28)

Ollllleeeeee Mango!!!

Guitar sounds muy flamenco to me! Looks great, nice playing, You are a true renaissance man!

The trebles sound nice and bright. How does it compare to your first one?




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