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sequoia
10-08-2016, 07:52 PM
Picture below of a ziricote back that is going to be an extreme pore fill challenge. Sanded out to 320. These are not so much pores as crevasses. I've tried to fill these things in ziricote before and it took forever and was a lot of work using a clear filler and many, many subsequent coats of shellac. It worked. Sort of.

I came across a Robbie O'Brian video of pore filling using saw dust and shellac and thought this might be a good time to try it. Anyway, these sorts of "pores" are beyond my usual methods. Has anybody tried this method? Picture below of wood in question and link to O'Brian's Tips du Jour video.

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https://www.youtube.com/watch?v=EcRc1cJrgtU

tparse
10-08-2016, 10:32 PM
Spray on a sealer. Mix some black water based dye into some sheetrock mud. Apply with a credit card.... sand back... another coat of sealer reapply until filled. Don't sand back through the sealer or the black dye will stain your wood. Top off with sealer and then do your top coats.
I do this all the time with Padauk , it also has canyons in it.

Michael N.
10-09-2016, 12:07 AM
I've tried that saw dust method with mixed results. It took a lot more applications than I was expecting, to really fill the pores that is. One aspect of pore filling that is often overlooked is how it blends with the actual wood and whether it gives a natural look. I find the clear fillers often give the better looking results. If you look closely at your picture you will find that the deeper pores look darker in colour than the shallow pores. Many fillers end up making all the pores the exact same colour. I'm not saying it looks bad, just that it doesn't look as natural as using a water clear filler. Shellac looks the part but takes a long time to fill pores. I've never used CA or Epoxy but I can see those working well, at least in terms of colour. Recently I've been using just clear oil varnish, applied very liberally. I've also tried this with Tru oil but you really need to forget about the usual method of application. Tru oil is a bit on the thin side, you really have to be very excessive with it. It also takes 4 or 5 applications, although each application is easy and quick enough to put on. I just use my fingers to work it into the pores. Oil can really darken the timber so it's best to do a test piece. If you don't like the result you can apply a couple of quick coats of shellac first.

Yankulele
10-09-2016, 05:47 AM
What I've noticed about Tru-oil and shellac is that they both continue to shrink for a very long time. I did one uke with the Tru-oil pore filler and then Tru-oil. It was perfectly flat when I finished it. Months later, the material has shrunk back into the pores. I guess I should pin that on the pore filler more than the Tru-oil itself, but it does make me wonder how long it takes for the finish itself to stabilize. I know you have done a lot of work with shellac, Sequoia; don't you find it takes a long time to finish shrinking and hardening? Seems like you would need a very long finishing schedule to be sure your pores wouldn't reappear over time. I haven't tried epoxy, but Allen certainly uses it to great effect. I find the Starbond CA works really well on deep pores, though it is pretty fumey to work with.

Nelson

lauburu
10-09-2016, 10:31 AM
I have had some success with shellac and pumice powder (rottenstone). Sprinkle pumice on the surface, dip a cloth in shellac and using a circular motion, rub the pumice and shellac into the wood so that it forms a slurry. You can add a bit of sawdust to bulk it up. Wipe off across the grain. Let dry. Repeat. Let dry. Repeat until satisfied. It does shrink back a bit but it's pretty low tech and the fumes are not unpleasant
Miguel

Michael Smith
10-09-2016, 11:28 AM
I seem to get the best results with zpoxy. I have tried the clear water based fillers and had no luck especially with pores that size. You can always lay the epoxy over those areas a little thick and srape it back.

Allen
10-09-2016, 05:07 PM
Ones that deep are going to benefit from an epoxy fill. Even then it'd going to take at least 3 sessions.

If you go with something like a shellac / dust or pumice fill, the potential for sink back or movement over time is probably going to leave you dissapointed.

sequoia
10-09-2016, 05:49 PM
Some before and after pictures of the attempted fill. Three sessions with sand-outs in between. Silver bullet? No. But this is a pretty extreme case. Only partial fills. I'm going to continue with a waterbased clear filler and then finish out with shellac... Yes, in this case zpoxy is probably the way to go and is shinkage going to be an issue down the line. Quite possibly... Onward! Into the fog!

Before

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After

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dwh
10-09-2016, 10:00 PM
Eye see progress! Perhaps pernicious patience and application of the same will succeed!

Dan Gleibitz
10-09-2016, 10:37 PM
Good progress. Looks like a pretty piece of wood. I've never been a fan of the way ziricote looks, but this might change my mind.

Beau Hannam Ukuleles
10-11-2016, 06:01 AM
Ones that deep are going to benefit from an epoxy fill. Even then it'd going to take at least 3 sessions.

If you go with something like a shellac / dust or pumice fill, the potential for sink back or movement over time is probably going to leave you dissapointed.

Yes, and yes.
No grain filler is ever a one application deal. Its min 2 applications but 3 or 4 are totally normal....so we should all just get used to the norm :)

Rrgramps
10-12-2016, 06:29 AM
Zpoxy or something thick would be needed for those bigger crevices. I've used Tru-Oil in the past, but would like to use water base finish with maybe Aqua Coat for general filling.

https://images-na.ssl-images-amazon.com/images/I/51674HKeJZL.jpg

I've heard good reports on Aqua Coat Clear Wood Grain Filler, and have it in my saved cart to try. Any negative experiences?

saltytri
10-12-2016, 07:23 AM
I've only done test panels with Aqua Coat. When applied to wood that has been thinned down to what we would use for ukulele bodies, the water content curls the panels quite a bit. This happens even if the wood is first coated with shellac. They do mostly flatten out when it dries but usually not entirely. This has deterred me from using it on an instrument. It does dry quickly and is easily scraped and sanded. I'd be very interested in hearing about experiences that others have had.

Michael N.
10-12-2016, 07:52 AM
Zpoxy or something thick would be needed for those bigger crevices. I've used Tru-Oil in the past, but would like to use water base finish with maybe Aqua Coat for general filling.

https://images-na.ssl-images-amazon.com/images/I/51674HKeJZL.jpg

I've heard good reports on Aqua Coat Clear Wood Grain Filler, and have it in my saved cart to try. Any negative experiences?

Complete waste of money for me. I didn't like the smell, optically it isn't that great, it takes 3 or 4 applications. Like many things, it will fill pores, just nothing to write home about. At least Tru Oil will pop the grain.

saltytri
10-12-2016, 03:53 PM
At least Tru Oil will pop the grain.

True enough! This claro tenor was done with nothing but Tru-Oil. It hasn't yet been buffed but is looking pretty good anyway. Tru-Oil can be used to pore fill by diluting it with mineral spirits and wet sanding to produce a slurry that fills the pores. Claro has big pores but it works out fine. Start with maybe 220 and work up to about 800. The number of coats and the grits used depends upon the hardness and porosity of the wood. Once the surface is smooth, subsequent coats can be laid down without sanding to build thickness. Wet sand with fine paper and water as necessary to keep it decently smooth during the build coats. Yes, I know that it will shrink back over time but most finishes do. Look at a fine instrument that has been sprayed with nitro and has had a couple of years to age gracefully.

There is something to be said for using a single product for the entire process. No need to worry about incompatibility of different products or to use shellac or something else as a tie coat.

https://c4.staticflickr.com/6/5825/30290083435_95a5701385_h.jpg

https://c4.staticflickr.com/6/5542/30290084515_2519aa4b63_h.jpg

sequoia
10-12-2016, 07:07 PM
It hasn't yet been buffed but is looking pretty good anyway.

Looking pretty good? It looks great! Lovely finish. (nice miters too)... How many coats did you do?

saltytri
10-12-2016, 07:42 PM
Thanks! I wouldn't want to keep track of how many applications this takes. That might ruin it for me. :) Suffice it to say many. This really shouldn't deter anyone, though, because the actual amount of time that is devoted to a finish like this isn't too terrible. It comes in reasonably small segments of time spread out over a long period. If you have to get the finish done quickly, try something else. I usually do all of my finishing early in the morning and it gets to be an enjoyable routine. Drink coffee, read the mail, push each finish along, wake up tomorrow and do it again. Kind of like "Groundhog Day" without Andie MacDowell and Bill Murray.

sequoia
10-12-2016, 08:04 PM
Kind of like "Groundhog Day" without Andie MacDowell and Bill Murray.

Ha! Well put. I can relate. At least "Groundhog Day" finally ended. Sometimes with shellac I wonder if it is the movie with no end. But like you, I actually enjoy the process. Some Japanese Zen master once said that patience is the greatest of all virtues. He must have done instrument finishing. Patience is a very powerful thing.

Rrgramps
10-12-2016, 11:47 PM
Salty, sequoia said it; that does look great. Your effort and experience really show.

Michael N.
10-13-2016, 05:42 AM
Looking pretty good? It looks great! Lovely finish. (nice miters too)... How many coats did you do?

I have only done a couple of full gloss finishes with Tru oil. I think you would be looking at around 20 minimum. I've heard of folk doing as many as 30. Somewhere between the two might be about right. It really is hard to say because much depends on the actual finish of the raw wood. Putting on that many bores me. With a brushed oil varnish I only have to do 4 or 5 coats, done.

saltytri
10-13-2016, 11:27 AM
No, not THAT many. This is not the "wipe it on and then wipe almost all of it off" approach that some use and that Mya-Moe illustrates in its videos. I do use that method when a non-filled finish is the goal. When a glossy and smooth (which are not the same thing at all) finish is the goal, Tru-Oil can be wiped on more heavily, not wiped off, and left to level as it dries. This can't be done well with the product right out if the bottle. I has to be thinned in an amount that I can't specify in numbers but that one can learn with experience. There is a point at which the balance of thinning and careful application enables it to go on with some thickness without running and to level pretty well.

I've never used oil varnish of the particular variety that is used on violins, which I assume is what Michael is referring to, but I'd wager that he is pretty good at it!

fungusgeek
10-13-2016, 11:35 AM
A note about wet-sanding TruOil. I used to do this and it was kind of a pain, and hard to see how things were going 'under water'. I recently found a paper that is set up so you can sand things dry. It is a bit expensive, but it does a wonderful job of fine sanding TruOil dry. The paper does not load up much, and a little paper goes a long way. I divide the sheets and the backer pad into quarters to give me a small sanding block. See http://www.eagleabrasives.com/buflex.html "Buflex Super-Tack Sheets - DRY". They will even send you a free sample to try out.

Michael N.
10-13-2016, 11:51 AM
Brushing on oil varnish is pretty easy (unlike spirit varnish). With oil varnish it's dust that is the problem, dust from the air, dust from your clothes, dust on the instrument, even tiny bits of old varnish from the brush. These can all be dealt with but you do need a methodical approach. It's more about hygiene. With the wiping varnishes it all becomes much less of a problem because the stuff is going on much thinner, you don't get the accumulated finish around dust nibs. It's also impossible to get varnish runs or 'curtains' as they sometimes call them. For some reason I prefer the brushed on varnish. Probably because I have a huge collection of brushes and somehow I have to justify having them.

saltytri
10-13-2016, 11:54 AM
Thanks for the reminder about Buflex. I've got some and haven't tried it yet but will soon. LMII has it:

http://www.lmii.com/products/finishing/abrasives/buflex

sequoia
10-13-2016, 06:19 PM
I love the Buflex stuff. Unfortunately I've been using my free two sheets for about 5 ukes and the stuff is getting a bit tattered. I might actually have to buy some. It is worth it. This stuff is great. I use it as the final sand before I go to buffing compounds. What I love about it is it dry although you do have to work up to with some wet sanding. I think this stuff makes the higher grit sandpapers obsolete.

Wildestcat
10-13-2016, 11:48 PM
A note about wet-sanding TruOil. I used to do this and it was kind of a pain, and hard to see how things were going 'under water'. I recently found a paper that is set up so you can sand things dry. It is a bit expensive, but it does a wonderful job of fine sanding TruOil dry. The paper does not load up much, and a little paper goes a long way. I divide the sheets and the backer pad into quarters to give me a small sanding block. See http://www.eagleabrasives.com/buflex.html "Buflex Super-Tack Sheets - DRY". They will even send you a free sample to try out.

In the UK, I use the Mirka Abralon 4000 grit foam backed pads for final "dry" buffing out of a Tru-oil finish. http://www.decoratingdirect.co.uk/viewprod/m/MIRABRA/.

I also use the Mirka Mirlon total finishing pads in 1500 & 2500 grit for between coats de-nibbing, again used dry and backed up with a rubber block cut from one of those novelty giant erasers. http://www.decoratingdirect.co.uk/viewprod/m/MIRKA_MIRLON_TOTAL_FINISHING_PADS_115_X_230MM/