Club Meeting 6 July 2016
Report by Earl Culham
Lindsay’s demonstration commenced with the comment that there are two stages to finishing, firstly to finish your piece to a high standard with chisel and sand paper followed by the application of an appropriate finish for the type of wood used.
To demonstrate stage, finishing your work to a high standard; Lindsay used some demolition rimu which in his terms was “manky”. By manky, he meant that the fibres in aged timber start to breakdown making it difficult to finish with the chisel especially on cross grain. It is easy to get a tear out and if you try to sand the defect out, it is easy to get heat checks when working with rimu. The only way to remove heat checks is to cut them out with the chisel.
It is essential to have a very sharp chisel and use fine cuts to achieve the desired smooth finish prior to sanding. Use as high a speed as you are comfortable with when making the final cuts and reduce speed for sanding.
Lindsay used drinking straws to demonstrate the best technique for cutting through fibres rather than tearing them e.g. a straight cut across the fibre will tend to tear rather than cut. Cutting at an angle across the fibre will achieve a smooth surface.
Rimu is a very dusty wood when being sanded and the dust can be quite irritating. Use a dust mask for protection and ondina oil is useful to reduce the dust. Sand through the grades to 400 grit or higher if you wish.
There was a suggestion from the floor to use sanding sealer before using ondina oil so that it didn’t soak into the end grain and cause the end grain to be darker than the rest.
There are many different types of finishing products available and it is a matter of personal preference which you use. Lindsay used the following products to show the different finishes that can be achieved:-
Briwax on its own, the result was a low sheen.
Sanding sealer applied and then the wax gave increased sheen
Boiled linseed oil thinned with vegetable turpentine by 10-15%, low sheen.
Sanding sealer applied and then the boiled linseed oil mixture, increased sheen.
Wattyl lacquer, thinned by 50%, high gloss.
Beall buffing system, using Tripoli, White diamond and Carnauba wax, produces a high gloss finish.
Thanks Lindsay for a well prepared and informative demonstration. We are all aware now of the pitfalls associated with “manky” rimu.