Greg's First Build - LP-1MQ #151

[GregLane]

StewMac has responded

Thank you for contacting us. You can absolutely add the ColorTone Liquid Stains to Tru-oil to color it. These stains work with virtually any finish and this should reduce the bubbling you are experiencing.


So now I have some experimentation, testing and decision making to do

[vh2580]

Well thats interesting

[wazkelly]

That is great news and really opens up a lot of options for anyone contemplating using full strength Color Tone sourced from the US.

[GregLane]

How many of these can I have. Here goes
AaaaaaAaaaaaaaaaaaaaaaaaaH. ( Just a little one)

Nobody told me a 1500 microfibre pad is not 1500 sandpaper equiv. And I didn't stumble across the fact in all my guitar finishing research. IT IS 600 - SCRATCHY SCRATCH all over my very satisfactory Tru-Oiled mahogany base.

After 10 days of Tru-oiling I was embarking on my final few coats and went to "1500". Well I now have scratches under the last coat so off it comes tomorrow. It has been a slow process because I have been rubbing off each coat. I only found out a couple of days ago you only rub off after the grain has filled. Oh well what's another week. Thank goodness for the forum and internet.

[wazkelly]

Lucky it was on the back and not front. May not need to sand it all off, just smooth out as much as you can with finer grit paper and start getting some more layers down.

If feeling brave take & leaf out of Ponch's book and apply TO with 2000 grit in wet sanding motion as that is supposed to grain fill and would certainly help to flatten out any scratches lurking lust below the surface.

[Simon Barden]

I did post on the differing grit size issue a few days ago, but it wasn't until I then when I found the grit equivalence table that I realised that the Micromesh grits were also a different standard. I'd previously only realised that the US ANSI and European grit sizes varied after reading the StewMac Guitar Finishing Step-by-Step book, otherwise I wouldn't have known any different.

http://www.buildyourownguitar.com.au...ead.php?t=6500

[GregLane]

Not deep just fine and numerous. Grain is 99% full and the light sand to fill the scratches will probably allow the last few coats to finish them as off. I am impressed with Tru-oil.

[Simon Barden]

Micromesh is really designed for final polishing, so if you start on a coarse grit, you really need to continue to work your way up through the grits until you end up at 12000. that way any scratches caused by the coarser-end grits will be removed by the finer grits (or rather, replaced by finer scratches which in turn get replaced by even finer scratches etc.) .

But you also need to choose the grit size with a purpose in mind. If you still need to flatten the finish because its got bumps and dips in, then you are going to need something fairly coarse to take off enough material to do that. You only really want to do this before a) applying a colour finish and b) after the colour finish has been applied but with enough clear finish on top so that you don't sand through into the colour, and risk removing a layer or even scratching though, back to the wood. But if it's already flat, then start on a finer grit, and work up from there. If you've got the odd lump of something sticking out, then you can very lightly run some fine paper over once or twice, which should drag it off - but even then, the finish should be hard/dry enough (especially with lacquers and paints) so that the lump doesn't pull several layers of solvent-softened finish with it.

[GregLane]

Yeah! That was the problem. The surface was perfect and this was to be the first finishing coat. But 1500 microfiber is not finishing grade.
Oh well now I know. I guess this is all to do with "first build" and "learner". Well back a couple of layers and forward again.

[GregLane]

Finally finished Tru-Oiling the mahogany base. Pleased with the result and very happy with the finish. I have oil finished furniture in the past and Tru-Oil is the most forgiving I have used. Might be a bit expensive for a whole dining room suit though.

I learnt a lot:
1. Should have done two fills of Timbermate.
2. Finish filling the grain with Tru-Oil before wiping off future layers.
3. I used the Norton equivalent of 3M scotchbrite ( equivalent of 1000-1200 grit). Rubbed the shine off every application before the next.
4. Did two extensive sand offs with 1200 wet and dry(dry - too frightened to put water anywhere near the guitar) at about 10 and 15 applications. These were forced by one bad application that went a bit bubbly on the grain for some reason. The second was required after I use the wrong microfibre grade (see above).
5. Finished off with a pre sand of 1500 microfiber, the a 2400 before the 50% turps finish this morning.

Now back to the quilted maple top.