Thursday 7 August 2014

Post 165 Bonsai table consturction - final

After finishing the basic build the final step is the finishing, always the most telling.
No preliminary photos this time. From the finished job the process was sanding with successively finer sandpaper down to about 280 mesh. If you were much more serious you'd go on to 800 mesh but that's not for me.

From then you are then faced with basically two alternatives; stain followed by varnish or stain and varnish in the one product. The problem with the combined stain varnish product is that it is much more like a paint and after three coats any woodgrain gets lost. If you build with something like pine that will be fine but with a higher quality timber it is nice to retain the visual impact of the grain.

I wanted a good dark colour and so went for the Cabot's wallnut stain. On the test timber it had a little of the red tones as well as the dark brown. The mahogony was just a little too red.

To get the visual grain you have take the stain first route. Now the trick with staining timber is that in the construction you have to be very careful with the wood glue. Where PVA glue gets wiped onto the timber surface at a join it seals the timber surface and prevents any stain application from being effective in that area. So it is critical in the build when glueing joints that you don't use excessive amounts of glue and any that is forced from the joint be wiped off with a wet cloth before it dries. PVA is water soluble and so it can be removed from the surface when wet. This doesn't matter with the stain varnish but is critical when staining for later varnish.






I have a friend who like to finish with a oil product which needs a number of applications and lots of buffing. I find the oil finish to be a bit blotchy on coverage and have to say I perfer the spray on Polyurethane. It gives a repeatable certain finish and a good durable surface. I put about 5 coats on the table with a light sand after the third, very easy to apply and brings the stain to life.
Lots of hours to get this done but pretty rewarding in the end.

No comments:

Post a Comment

Happy to hear your advice, feedback or questions