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neksmerj
7th November 2007, 11:00 PM
Dear members,

Just mucking around, I turned up a couple of small jewellery boxes, with lift off lids, out of solid Jarrah. Struth, the timber was as hard as a rock. They are approximately 62mm in dia x 20mm high, with the centres machined out leaving a 5mm thick base.

When it came time for the final finish, I had a problem.:C

Sanding with wet and dry, 800 through to 1200, I just couldn't get a mirror finish where the tool had cut across the grain. With the grain, no worries.

Question, do I keep persevering with sanding, or is it better to fill the end grain, say with Timbermate filler, then try sanding again.

I'm trying to get the sort of finish found on an old piano. Smooth and shiny with a lovely patina.

Can post some pics if you want a squize. In the top of one of the lids, is an inlay of three concentric rings, aluminium, brass and copper.
Has a nice "Art Deco" look about it.

Any clues?

Regards,

Ken

Cliff Rogers
7th November 2007, 11:26 PM
Post some pics if you can.

2 points... (make that 3)

Point one. The shine on a piano is not from sanding alone, it has a 'build' of finish on it, a shiny coating.

Point two. Some/most timber looks better on the side grain when compared to the end grain.

Point three. End grain can look bad/dull if it is torn.

You have to be very careful to get rid of all the torn grain before you progress through the grades of sanding or it will show up.

I find that shear-scraping can help.
I also posted some details of how I dealt with torn grain in the critique thread (http://www.woodworkforums.com/showthread.php?t=57523). Look at posts 60 & 61.

Once you have removed all the torn grain, then & only then can you progress through the grits & you have to remove all the scratches from the previous grit before you move to the next.
IE: if you are going 120 180 240 etc, while you are on 180, you have to remove any scratches made by the 120 before you move to 240.

I actually go 120 150 180 220 240 320 400 EEE (http://www.ubeaut.com.au/eee.htm) & then apply a finish.

I sometimes use a courser grit than 120 for timber that tears out.
I have some 80 grit that I with a power sander for torn end grain if nothing else will work.
I have also found that 100 grit disks on an angle grinder on large work can save a lot of time fiddling with torn end grain on Rain Tree.

Skew ChiDAMN!!
7th November 2007, 11:27 PM
What, exactly, would you be filling with the Timbermate?

If it's tear-out from the tool, then you'd be best off by sanding with, say, 120 grit until all signs of the tear-out are removed. Then work down through the grits until you have the finish you want. 150, 180, 220, 240, 320, 400, 480... don't skip any 'cos that's false economy. You'd need to work twice as hard with the next grit to remove all scratches from the previous grit. (And when hand sanding, don't sand in one direction all the time - 'tis better to sand in small circular motions so you're not leaving heavy, parallel grooves.)

If it's just a very open-grained timber and you want to fill the pores, then I'd be sanding back to bare wood and using a nitrocellulose end-grain sealer instead of a putty... 'cos this is what NC sealer is designed for. :U Then work through the grits, apply your finish and you should be very happy with the result.

Edit: beaten to the punch by Cliffy. Again. :roll:

rodent
11th November 2007, 07:19 AM
You could also try sealing the end grain with shellac . then doing fine cuts to remove the torn grain then go on with your finishing .