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View Full Version : need to fill a gum vein, where do I get powder colours?



ian
16th November 2008, 09:35 PM
Finishing seems to be the right place for this ...

I've built a table from KD tassie oak and am ready to finish it

the top has a very prominant gum vein about 1.5mm wide, 200mm long and aout 3mm deep

the dried gum is a sort of dark red-purple and is very brittle
I'd like to fill the hole with epoxy coloured to match but where, in Sydney, can I get the powdered pigments?
Stimpsons in Balmain used to carry them, but have since closed their doors.



ian

andrewsd
17th November 2008, 12:34 PM
True pigments are available from antique restorers and polish suppliers online but you can get by with the range of oxides etc available from your local hardware store (Bunnings have a good range). You can also get universal tints from your paint supply store which work very well.

Big Shed
17th November 2008, 12:43 PM
True pigments are available from antique restorers and polish suppliers online but you can get by with the range of oxides etc available from your local hardware store (Bunnings have a good range). You can also get universal tints from your paint supply store which work very well.


Bit intrigued here, what do you define as a "true" pigment?

Waldo
17th November 2008, 12:51 PM
G'day Ian,

These blokes sell them http://www.solidsolutions.com.au/view_products.php?cat=14

I'm waiting on a delivery of black dye from them, can't comment on the product, but elsewhere in the Forum someone recommended them.

andrewsd
17th November 2008, 02:19 PM
I'm just being a bit of a purist here. In the old days pigments were derived primarily from natural sources such as dirt (inorganic pigments) and plants (organic pigments) for painting and colouring, etc. Technology then led to the development of synthetic pigments (from the 1860's). For example, ultramarine was once made out of crushed lapis lazuli but is now almost universally produced as a synthetic pigment.

For antique restorers it is sometimes important to have access to the traditional natural pigment as opposed to modern synthetics or synthetic/natural blends but for most furniture colouring applications the distinction is largely unimportant.

Big Shed
17th November 2008, 04:25 PM
Well I'm only a simple paint chemist, and I don't know what being a "purist" has to do with it, but if a substance is being used as a pigment it is a pigment.

So, forgive me for being pedantic, therefore any substance being used a a pigment is a "true" pigment.

Having said all that, and getitng back to the original question, any of the oxides will do the job, or any of the universal colourants can be used. They are basically pre-dispersed pigments, some of them being oxides or carbon black.

Last time I needed to do the job you are talking about I went to my local big green shed and asked them to squirt some universal colourant in a little jar, I used an umber colour, and they were happy to so and didn't charge me anything.

andrewsd
17th November 2008, 06:01 PM
Bigshed,

My use of the word "true" was in an historical context, as I thought I made clear in my last post. I also said any distinction between "true" and synthetic pigments was largely irrelevant for most purposes.

Perhaps "traditional" as opposed to "true" would have caused less concern. It would, I agree, be the more accurate choice of words. You are undoubtedly correct that if something functions as a pigment then it is a pigment and I didn't mean to cause any confusion on that point. Still, if you are trying to match something that was tinted with a "traditional" pigment and you want to use the exact same thing (either because the job is extremely valuable or because you are just an obsessive purist) it is good to understand that you might have to go to a specialist supplier for the traditional pigment.

Consider me corrected though for the choice of words.

Would you mind helping me out with another query I have been trying to nail down on this site? Have you ever come across an old Wattyl product called "Crystal Veneer"? The line has been deleted but I have been told by many old polishers that the stuff was fantastic and they haven't come across anything quite as good since. Would you have any idea of what was in it? I would be very grateful for any help you could offer me on this point.

Regards

Andrew

dai sensei
17th November 2008, 08:30 PM
You can also try http://www.modelit.com.au/, they also sell metal fillers too like brass, copper, silver & gold.

Waldo
17th November 2008, 10:11 PM
Thanks Neil,

I was going to PM you and ask where you got yours from. :2tsup:

pugwash
17th November 2008, 10:58 PM
I have used ordinary (and cheap) powder paint from an art supply shop.

ian
18th November 2008, 12:06 AM
thanks everyone

last time I needed to do this I had access to a range of powdered earth (ochre?) colours – colours like burnt umber, ventian red, burnt sienna, raw sienna, purple, black

Is there any incompatibility when using liquid paint colours in epoxy or grain filler?

just on grain filler, is there any reason not to use spirit stains.

I've tried two different art supply stores in Chatswood, but neither carry powdered artists colours
so I'm interested in sources in Northern Sydney



ian

custos
18th November 2008, 12:19 PM
Finishing seems to be the right place for this ...

I've built a table from KD tassie oak and am ready to finish it

the top has a very prominant gum vein about 1.5mm wide, 200mm long and aout 3mm deep

the dried gum is a sort of dark red-purple and is very brittle
I'd like to fill the hole with epoxy coloured to match but where, in Sydney, can I get the powdered pigments?

I'm not sure why you even want a pigment. I make a lot of stuff out of KD Tassie Oak and this is another suggestion for gum vein. Scrape out all the dried gum resin so you have a reasonably clean grove. Darken up the bottom of the groove if you want - anything works okay for this even dark brown or black texta - but not usually necessary. Then slightly overfill the groove with Glass Coat (http://www.glasscoat.com.au/) available from Bunnings. After it hardens, sand it down flush, sand down through the grits as you would normall for the timber and the glass coat goes pretty clear. Finish with Danish oil (I use Organoil) and wax, or whatever other finishing method you prefer... two pac, Wattyl Speed Clear,.… ny of that works. The final appearance is really great -- perfectly smooth finish with the nice gum feature. If you colour the epoxy it just looks like coloured bog in my opinion -- the variation in colour and texture of the gum vein (which you can only see with a clear filler) is what makes it look nice.
Cheers.

timdavis@activ8
19th November 2008, 06:09 PM
I sand timber floors all the time that are covered in gum veins. The simplest, cheapest and after much experimentation I've found Ebony/black coloured Timbermate wood filler looks the best and most natural solution. Scrape out loose gum and fill then sand off excess. Gum veins look black when finished/coated anyway.

ian
26th November 2008, 11:40 PM
Thanks everyone who responded

ended up making up a batch of customed coloured filler

will post a photo after the weekend



ian

hughie
28th November 2008, 11:25 AM
Ian consider coffee grounds they match up very well with.

Sprog
28th November 2008, 11:43 AM
Would these work?

http://www.ubeaut.com.au/dye.html

CameronPotter
28th November 2008, 02:34 PM
Ian consider coffee grounds they match up very well with.

Funny, I saw this thread and came in to suggest this very thing...

I haven't seen anything to match it as most tinted epoxies end up looking like a fake solid colour (in my opinion at least). The coffee grounds add a bit more depth while still filling the crack very well.

Cam

ian
30th December 2008, 11:06 PM
Thanks everyone who responded

ended up making up a batch of customed coloured filler

will post a photo after the weekend

ianwell it took slightly longer to get and post a photo

first pic is the top prior to filling the gum vein,

the second pic is the table in my mother-in-law's house — it's her Christmas present

I ended up filling the vein with timber mate tinted with a mixture of Feast Watson spirit stains – red, black, blue and mahogony
I mixed it on a white tile and added a drop of colour at a time till i was happy with the purple/black colour

thanks everyone for your comments


ian

woodhunt
10th January 2009, 08:42 AM
I think natural and synthetic pigments would have been less provoking a term than 'true'.

Crystal veneer I spotted in one of the supply catalogues- it was either goods & chattels or browns possibly in 4L containers.

Harry72
10th January 2009, 03:31 PM
Would these work?

http://www.ubeaut.com.au/dye.html


Yes and very well I might add, depending on how much added it can be transparent like gum.
I wouldnt do this in a stressed structual application tho.

old pete
10th January 2009, 08:31 PM
Just whiz along to your nearist art suppliers for the appropriate dry powder paint to mix with your epoxy. Also add about 50% by volume of talc to the epoxy to make it more easily sandable. Before filling the gum vein mask its surrounds very carefully with masking tape. This makes the job of subsequent sanding infinitely easier. Good luck


Old Pete