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rsser
11th March 2005, 08:08 AM
I'm turning a Jarrah burl, with the 'pimpled' surface on the outside. There's a significant crack about 50mm in from the edge running at right angle to the radius that extends about half the length of the piece at that point.

Having read that you can colour epoxy and use it to fill and glue the crack, I'm wondering whether you can use Blutack on the bottom over the pimples to stop it running out. Or whether the two will make a mess.

I know some people use medium viscosity CA but I never use this otherwise and already have the epoxy.

Advice gratefully received!

Kev Y.
11th March 2005, 08:13 AM
Ern, YES.. also if you can get some, plasticine is just as good.

rsser
12th March 2005, 04:29 PM
Thanks Kev. Don't mind going into Toys-r-us and asking for plasticine (often in there for big chalk sticks to make pipe-bowl filters ;-} .... )

Any tips on colouring epoxy? Have heard black oxide works well, but I suspect it will only come in large packs for concreters. But I do have on hand the Feast Watson spirit-based Jarrah stain, as well as the ubeaut set of water-based stains which mixed together would produce a mucky dark colour I'd guess.

Ozartisan
12th March 2005, 08:45 PM
Hi Ern
Have used West's resin (from Carbatec) with great success in quite a few of my turnings.
Wanted to create some special effects, so went searching for something that would colour it without affecting it's properties.
Found this place - VERY helpful (in Sydney so I called in) - but I am sure they will help via email &/or phone
http://www.barnesproducts.com.au/barneshome.htm
Have attached a pic of a burl where I filled some ant eaten area with West's then turned. No colouring in this one.
I have used good old PVC duct tape with success to contain the resin in part turned pieces, but you need to ensure a very good adhesive contact, with lots of tape contact area around the gap you are covering.
Good luck - show us the results when you are done.
Peter - Happyinsydney (for a while anyway!!)

rsser
13th March 2005, 08:07 AM
Thanks Peter.

Nice piece - Red Mallee Burl?

Ozartisan
13th March 2005, 09:45 AM
Yes Ern - Red mallee
Wanted to keep that piece - but a guy with some cash & a desire to give his wife something different for christmas won out!
Have been down to Brads Burls since & picked up a few more mallee & coolabah burls to attack - when I get some shed time!!
Here is the first brown mallee burl I tried with west's resin, shows how I used duct tape to create the well on the partly turned piece....
Turned that piece when I only had my GMC Bunnings special! (Quite a step from that to the DVR!!!)

rsser
13th March 2005, 09:59 AM
Good stuff.

This is a RMB that I worked on with my teacher, Andrew Potocnik; more of his talent there than mine ;)

rsser
17th March 2005, 07:30 PM
Well just for the record ...

The blu-tack stopped the leaking of the epoxy (which was thinner cos of the stain) but it did in fact stain the epoxy in places up to the top of the crack.

So it's out with the black felt tip pen to emulate a sap line. And I swore I'd never decorate a turning with paint!

Little Festo
18th March 2005, 09:54 AM
Ern,
Had a similar problem and used a waterbased wood putty. Worked well.


Peter

rsser
18th March 2005, 10:06 AM
K. Like Timbermate? And then picked it out or left it in?

Little Festo
21st March 2005, 10:08 AM
Ern,

I picked it out and being water soluable was quite easy to remove, was Timbermate too. I suppose you should decide weather it will be easy to remove from where you want to plut it, small deep holes could create some problems - if the the putter becomes embedded there.

Peter

rsser
21st March 2005, 10:15 AM
Yeah - natural edge section, so lots of cracks and dimples. Couldn't pick it all out so used a rotary wire brush and that helped. There's still some there if you look carefully but some of the nat. edge is greyish so overall it's not a disaster.

Next time I'll inject the epoxy from the bottom before hollowing out.

Will post a pic once the final coat of oil goes on.

rsser
26th March 2005, 01:22 PM
Here it is: http://www.woodworkforums.ubeaut.com.au/showthread.php?p=132969#post132969

The Danish oil turned the tainted glued section black so that blended in OK in the end - well, looked like a sap line. However it also highlighted the scratches left in the natural edge by the wire brushing. Hey ho.

Grunt
26th March 2005, 03:01 PM
How to deal with a crack

Pull your pants up?

ozwinner
26th March 2005, 06:29 PM
Pull your pants up?
I knew you couldnt resist.......:p :D

Ive hanging to say something smart, but though, hhhmmm, no Grunt will do it.

Al :D

Canadian_Shawn
29th March 2005, 01:27 AM
Hey Ern,

I have had similar problems and have been trying a coloured wood putty to fix it. here in Canada we have wax crayons for hardwood floors, these come in a multitude of colours and are used to hide marring. I think once a piece is finished the crack can be filled with this wax and then buffed smooth. No paint, no sanding and you can match colours so no one is the wiser.

rsser
29th March 2005, 09:32 AM
Thanks Shawn. Yeah, we have them here too, used mainly by furniture restorers. I hadn't thought of them in this context.

But I also needed the filler to glue the sides together; it was going to be too risky without.