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Finger Dicer
2nd April 2005, 01:31 PM
I have just completed the top of coffee table made from a 50mm slab of Macrocarpa 900mm x 600mm, with a reasonable amount of the bark still on, but sanded to suit the shape.

It was made from a much larger piece, the other half is still in its native form.

The top has been sanded back to 400 grit, so its nice and smooth, also I have been able to antique it a little as well so that it doesnt look particularly new.
The idea being to add a bit of age to it.

I then applied a wattyl colorwood pigmented stain ( kauri ) to this, brushed over then wiped evenly with a cloth.

It was allowed to stand for 36 hours, then had 4 coats of amber shellac applied to give a really nice deep goldy brown look to it. The color is gobsmacking.

Take a look at these (scroll down the page). My one comes in somewhere between CT1 and CT2 so probably would retail for around $500.00 The color is almost identical to the CT1. http://www.dunpuffin.co.nz/Tables.htm

No SWMBO and I arent sure as to how long the shellac takes to harden to a durable fininsh.

The product used is http://www.zinsser.com/product_detail.asp?ProductID=31 as we can not get the ubeaut hard shellac at our local bunnings. The can doesn't state how long a drying time is required. Its been drying for nearly 24 hrs, but the surface still seems slightly soft. It also appears to be a wax shellac, although there is no reference to this on the website or on the can.

Any thoughts, should there also be a hard overcoat put on, and if so what?

I had to brush the coats on as it was too hot to pad, as it dried almost as soon as it hit the wood. This unfortunatley has left some brush markings, although it doesnt seem to detract from the overall finish too much.

Can shellac be succsessfully applied with a mini roller for a more even finish?

Gumby
2nd April 2005, 01:41 PM
Not sure on the curing time of that product but as you said, it dries almost instantly. Ubeaut's is around 24 hours I think. That's how long I leave the last coat before giving it the EEE treatment.

You'll find that if you dilute (cut) the shellac to 50% using metho, then apply with a pad, you won't have any brush marks at all. Give it a light sand and try this for the final coat. By using this method, you need more coats but they can be applied within about 20 minutes of each other (again , that's usung Ubeaut's stuff)

Sturdee
2nd April 2005, 05:18 PM
Whilst shellac dries very quickly and that you can put a number of coats on in quick succession it does take quite a while for all the coats to cure properly.

The old master that taught me french polishing last year instructed us to leave the piece alone for at least a week , preferably 2 weeks, before rubbing down with English whiting and a soft brush, to dull the shine so that it doesn't look too new, and waxing with a hard wax.

Anytime quicker and you don't get as good a finish as is possible. :D


Peter.

Finger Dicer
2nd April 2005, 07:01 PM
Okay ...will wait for a bit to let things cure then give it a couple of final coats at about 50%


By the way, this is the first time I've used shellac and I am impressed with the color and finish.

For most of my projects I can see me using it...its just too good a finish to not take the time with.

Getting a new camera in a couple of weeks so will post some piccys for you to look at.

Cheers chaps.

ozwinner
2nd April 2005, 07:08 PM
before rubbing down with English whiting and a soft brush,


Peter.
Doesnt it smell like fish after??

Al :confused:

Sturdee
2nd April 2005, 07:23 PM
Not the fish and chips variety Al. :D

It's a ground up chalky type stuff, finer than talc powder, and I believe it comes from the famous white cliffs of Dover. :D :D :D

Peter.

Gumby
2nd April 2005, 11:31 PM
Okay ...will wait for a bit to let things cure then give it a couple of final coats at about 50%


.

Give it a very light sand before you add the final coats .

rsser
3rd April 2005, 04:47 PM
Strongly suggest that you use as final coat some hard dewaxed shellac from Ubeat (you can order it from this website) - normal shellac looks good but needs a lot of care to keep it that way.

The Ubeaut stuff will only cost you a few bucks but will save you a packet.

ubeaut
4th April 2005, 09:46 AM
Initial drying time can be as little as a couple of minutes, depending on the quality and age of the shellac, however, full curing time is minimum of 2 weeks before leaving anything sit on the top or it may leave a lasting impression. Personally I recommend 4 weeks before leaving something like a vase or fruit bowl sitting on the table, preferably with a doily and cork mat underneath.

There really is no need for a final coat if you are prepared to look after the top by using tablecloth, place mats, coasters, etc to protect it. Don't put hot plates, cups, or anything that can mark the surface directly onto the surface and it will last for ever.

Don't expect to have the kids draw pictures on a piece of paper directly onto the surface and then have the surface come out unscathed. If that's the type of treatment it will get then laminex is the top you need.

Hope this is of some help.

Cheers - Neil :)

PS rsser - Thanks for the plug, good basic idea, however, I wouldn't recommend the use of Hard Shellac over the top as they wouldn't be completely compatible and would most likely move at different rates causing crazing of the top down the track.

echnidna
4th April 2005, 10:02 AM
"PS rsser - Thanks for the plug, good basic idea, however, I wouldn't recommend the use of Hard Shellac over the top as they wouldn't be completely compatible and would most likely move at different rates causing crazing of the top down the track."

Sounds like a cunning way to get an antiqued appearance to a table top. Wonder if a heat gun would accelerate the crazing.

rsser
4th April 2005, 10:08 AM
PS rsser - Thanks for the plug, good basic idea, however, I wouldn't recommend the use of Hard Shellac over the top as they wouldn't be completely compatible and would most likely move at different rates causing crazing of the top down the track.


Fair nuff.

How would you tho if you were starting from scratch .. a wash coat or two of normal shellac and then the Hard stuff? Or keep them apart from the start?

ubeaut
5th April 2005, 12:58 AM
Ideally use the Hard stuff from go to whoa. An initial base coat or two of our dewaxed white will be OK as it is compatible with the hard. Most other shellacs have a certain amount of wax in them and may move at a different rate causing the crazing.

The idea of a base coat is to stop the hard from keying to the timber thus making it a bit easier to affect a repair down the track and make it easier for stripping should it ever become necessary in the future. It is not essential to put down a base coat first.