17 May 2012
Machining a perfect rule joint from scratch is tricky at the best of times. My preferred technique is to creep up to a good fit in a series of shallow passes with the router and to make sure the leaves are a reasonable thickness in the first place. I’ve learnt this by repairing more than I’ve made and it’s a really good way of identifying weaknesses in furniture construction.
As part of an ongoing project I’ve been carrying out repairs to a small drop-leaf table in readiness for polishing and recording the process for a book on the subject of French polishing.
I quite enjoy grafting on new sections of material to carry out a repair. It begins by sourcing a good match for colour and grain pattern in the first instance and then for the join to be as fine as it can be. In most cases there’s little scope for clamping so a rub joint or piece of tape has to suffice.
I used a small core bit to get close to the profile on the first repair finally achieving a match with scraper.
The extra fine Japanese saw proved very useful in shaping up a couple of other repairs as well.
I didn’t notice at first but this table has obviously been in the wars. In fact an entire leg had been replaced at some point and it was interesting to compare the accuracy of the turned details. Close but no cigar I think.
Images, from top to bottom:
1. Use a nearest core bit to get close to the radius of the existing joint profile
2. A scraper gets you the rest of the way
3. The extra fine Dozuki was the perfect tool for trimming back the newly grafted on repairs
4. The universal 22tpi is a great tool for restorers as there is hardly any resistance in the stroke
5. No sanding, just a flick with a paring chisel and the repair was ready for polishing
6. New bead…
7. …old bead – much sharper
8. The new ovolo shape towards the bottom of the leg is slightly elongated…
9. … and not quite s full as the original
10. The hollows, coves and bevels are also clumsy by comparison...
11. … to the original (PHOTOGRAPHS BY GMC/DEREK JONES)Contact Derek Jones