Stopping the rot
Friday, August 22, 2014
Well, not quite stopping it but removing would be more correct. As part of my work with our local volunteer footpath maintenance group I get to do the woodwork, as that is my speciality. This week I"ve had two waymark fingerposts to repair - these are the signs that point in the direction of a footpath, bridleway or byway. Wood being wood, it rots in the ground usually in the first nine or ten inches of soil where the rain, loose soil, fungi and bacteria and woodlice conspire to attack the wood.
The first thing to do was to mark out a scarf joint on the fingerpost, avoiding the rot. The idea of a scarf is to help lock two lengths of timber together. On large beams a couple of cross wedges are banged into a through mortise in the middle to lock the sections together. In this case, as the oak sections were relatively small and rather rough in dimension and finish, I just opted to use angled screws to pull the two halves into each other. Having made the first half of the joint I transferred the shape on to the new lower stub and cut that out. The fit was checked and needed slight adjustment to make it fit together properly. I"m a big fan of polyurethane glue as it is gap filling and all-weather. I dosed the joint faces before screwing the joint together. I discovered the finger at the top of both posts was loose so a bit more glue sorted that out. Once dry, the surplus glue was chiselled away and as the stub timbers on both posts were larger in section than the posts. I used a drawknife to flare the sides neatly. The last act was to fit an "anti-vandal" bar at the bottom. This makes it hard for anyone trying to uproot the fingerpost!
I"m on holiday next week so I won"t be helping install the newly repaired fingerposts, but at least my fellow volunteers only have to dig holes and fill them in once the posts are set upright!
Photographs top to bottom
1. One of two fingerposts in for repair at my workshop
2. The rotted end. Wood always succumbs in the end to nature
3. Marking out the scarf joint, it is an easy joint to set out and cut
4. In order to end up with a neat joint it needs to be sawn from both faces
5. The finished joint, ready to make the other half
6. The two joint loosely placed together, the new oak needs to be shaped slightly
7. Once the PU glue has been added the screws are run into pre-drilled holes at an angle
8. The last important is the anti-vandal bar to prevent the fingerpost getting uprooted
(PHOTOGRAPHS BY ANTHONY BAILEY)