Thread: Filling Gum Veins

Hi Luke,
The only thing I can think of is epoxy, You can get different amounts of open time depending on the hardener it is not toxic when cured, can be coloured to what ever you want, accurate measure of quantities is all that is needed and a mixing cup and stick it is thin and will flow into veins well, wouldn't say you could plane it but scraping and sanding should be fine,good bonding strength, don't know about oil and wax though.
Regards Rod.

For stuff like that we use Techniglue epoxy with black pigment paste at work. I'll try to address your requirements in order.

It's fairly thick, so you have to use a putty knife or scrap of timber to push it in (it won't flow) and you'll need to go over it a second time after sanding it level to fill the small bubbles.
It isn't particularly messy as long as you're careful but it doesn't wash off so gloves are recommended and wear an apron or something you don't mind sacrificing to the gods of glue. It doesn't wash out. Ever.
It's a long cure resin, so fill at the end of your work session and leave it over night. It cures fine even with Melbourne overnight winter temperatures.
It can be planed, but highly recommend NOT doing it unless you're ok with gunk on the sole of your plane that is very tough to remove. Never tried scraping it, but sanding works fine.
It'll also take wax and oil finishes.

For small fills and touchups, 5 minute epoxy with the same pigment works but it needs considerably more than 5 minutes to harden. Leave it over your lunch break and it should be fine.

Yep, epoxy is good, or you can use Diggers casting resin which is polyester. They will take spirit based stain.
First, clean the vein as well as you can using acetone and a tooth brush.
You will need to seal off underneath to stop it running through, I use scrap ply or MDF stuck to the wood with hot-melt glue. On top, build a dam around the area to be filled using hot-melt, and slightly overfill. Depending on how deep the vein is, you may need to fill it in two or more goes.
These resins can be worked with tools, sanded, oiled and waxed.

Elan,

That sounds like the stuff.

Where can I get it?

Carbetec sell techniglue

I've used it mixed with spent coffee grounds in woodturning with good effect

...or get creative with the pigment in the epoxy...

glow.jpg

Hi again Luke,
Techniglue is great for larger cavities but for me if you are filling only gum veins west systems epoxy is a better bet it will run into thin areas and get better penetration. Polyester resin is less stable than epoxy and shrinks and moves a lot more.
Regards Rod.

If you want it runny, Techniglue is not the way to go

Originally Posted by Luke Maddux

Elan,

That sounds like the stuff.

Where can I get it?

Not sure where we get it but, as mentioned above, Carbatec sell it. We use Solid Solutions pigment paste for the colour.

I have used Techniglue for filling gaps in all sorts of timber (Oregon, red gum, blue gum, etc). It is also our epoxy of choice in our workshop. But as has been said, it is thick and gooey, not thin and runny. I use oxide powder as a pigment (same as is used for colouring grout or concrete). A little bit of oxide powder goes a long way. Techniglue sticks to everything and can be used to fill quite large holes.

For filling gums veins and flaws that are not too big, you can create a good filling medium, by sanding your redgum with 120 grit, and collecting the sawdust. If you brush your sawdust into the flaws, and flood with ordinary superglue, ( maybe 2mm layers), and leave the last layer proud of the surface. It comes up dark, but clear, and takes sanding down to fine grits, very well. Quite cheap, ( $2 shop). Don't think it would be too flash for plane blades however. An example is the dark marks in top of blanket box below.
Cheers, RedbogBlanket Box July 2013 005.jpg

On smaller gum lines, I've been known just to pump in some Titebond III and let it sit proud and then just scrape it back. If I am correctly informed, titebond 3 has ground walnut shells in it, and it matches the colour of my brown timbers quite nicely. I guess it could be coloured to whateva colour you like, but i dunno which product to colour it with.

I`ve been using epoxy with crushed Black Boy resin , natural looking.

At what point in the project would you guys suggest doing it? Should I go ahead and plane and dress the boards, cut the joinery, etc and then fill the holes and sand as necessary at the end? Or should I operate on each board and then continue with the project?

I like to have some thickness to machine off after any filling, 1mm or 2mm, any epoxy brew that that flowed out onto the surface and into the grain will be removed and you end up with a better defined and cleaner edge to the fault that has been filled, the downside to this is you never know if you are going to get any issues with the filler/fault at the new thickness.

Sometimes tho it is unavoidable to fill at the finished thickness and therefore need to look at ways of not allowing the filler to flow out and colour the grain around the fault, mask around the fault for eg

Like with most things there are pros and cons, just depends what works for you.




Pete