With the truss rod installed, I was able to put my router away and return to the (much less terrifying) hand tool work I prefer. Next up was fitting the ebony veneer to the headstock. The bottom edge of the veneer had some significant splits, so I trimmed that edge with my Bad Axe carcass saw. Fortunately the veneer was significantly longer than I needed, so even having trimmed the split edge the veneer was plenty big enough for the headstock. As the veneer is only a couple of millimeters thick it is very flexible. My bench top is not flat enough to keep the veneer perfectly flat while planing the gluing surface, so instead I stuck the veneer to a sheet of 25mm thick ply wood using double sided sticky tape. Double sided tape is one of the secret tricks in my workshop, and is invaluable for working thin stock, holding gluing cauls in place, and securing router templates (on the few occasions I use my router). Once secured to the ply wood, the gluing surface of the veneer was then prepared with a Lie Nielsen No.212 Scraper plane. This plane is invaluable for the work I do, as it scrapes difficult exotic timber leaving a finish ready surface with no tear-out, and is one of the go to tool in my workshop when dealing with timber that would tear-out under a more conventional plane. The bottom edge of the headstock veneer needs to fit against the back edge of the nut with no gaps. To do so it must be fitted in two directions: straight along the width of the headstock, and a chamfer planed into the thickness of the veneer so that the full thickness of the veneer buts up against the nut. Effectively, the chamfer is the angle of the headstock, plus 90 degrees, so that the resulting edge is perpendicular to the surface of the neck. The best way to fit the bottom edge of the headstock veneer is to mount it on the headstock, projecting over the surface of the neck, and to shoot it using the neck to support the plane. This method ensures that as the veneer is straightened along the width, the correct angle is also planed into the thickness of the veneer by virtue of using the headstock itself as the reference surface. I use my Lie Nielsen block plane for this operation, as the short length of the plane makes it easy to balance on the neck, and the sides of the plane are ground to 90 degrees of the sole which guarantees the correct angle on the chamfer. Not all planes have their sides dead on 90 degrees to the sole, so do check before you carry this task as there is a risk of planing a chamfer with some funky angles if you use an older plane. And from a different angle… To glue the veneer to the headstock I clamped a 300mm steel rule to the neck so that it provided a reference edge against the back of the nut. The veneer was clamped under a caul to spread the clamping pressure, and left over night for the glue to cure.The veneer was broken out of the clamps once the glue had fully cured. I then flattened the face of the headstock, again using the scraper plane. To check my progress with thin stock where I want to remove as little material as possible, I often draw across the entire surface to be planed. As the lines disappear it becomes clear where there are hollows in the surface, and where the high points are. The white pencil in the picture below has been with me since Totnes (8 years ago now!), and I suspect it has very few sharpenings left! The headstock is now ready to be shaped, which I will write about next time.
Issue 230 of Furniture & Cabinetmaking is now out and if you were to turn to page 42 you would see my latest article. This is a follow up to the parallel skills article I wrote for issue 227, and takes an practical look at two lutherie techniques which may also be of use to furniture makers.
Now that the new workshop is set up I’m making progress on the parlour guitar build, and fitting the truss rod was the next stage of the build.
For this guitar the adjustment nut for the truss rod will be at the heel end of the neck, which means that there is no need to cut a truss rod cover in the headstock veneer. I find myself leaning more towards this orientation of the truss rod for acoustic guitars, as I find the absence of a truss rod cover leads to a cleaner and neater looking headstock.
Orientating the truss rod this way does have some implications for the build process. With the slipper heel method of construction the heel block is an integral part of the neck, and a rebate is planed into the top of the heel block to accept the soundboard. As a result, the truss rod slot has to be cut deeper at the heel block end than the but end of the neck, so that there is sufficient clearance above the truss rod for the rebate. As a general rule cutting the truss rod channel 3mm deeper at the heel end is sufficient for allowing the rebate to be cut into the heel block.
Now, I’ve made no secret of the fact that my least favourite tool in the workshop is my router. That being said, there are times when a router is the best task for the job, and cutting the truss rod slot is one of them. To allow the router to cut the necessary slope I first trimmed two pieces of pine to length and using my No.5 jack plane, planed an incline in both, so that one end of each was to 3mm thinner than the other opposite end. Both pieces were then secured to the fretboard gluing surface of the neck using strong double sided sticky tape. This established the ramp on which the router would travel.
Taking shallow passes I routed a channel using a 10mm wide router bit, with the router edge guide registering on the side of the pine ramp. The channel ended up 13.1mm deep at the heel block and 10.1 deep at the nut. The traditional “U” shaped truss rod is 10mm square, and the extra 0.1mm is to account for the fillet that is glued over the truss rod.
I prepared the fillet by ripping a strip of yellow cedar off a soundboard off-cut, and planing to width. The open side of the truss rod was then covered up with masking tape to prevent the ingress of glue, and the truss rod was glued into the channel, with the open side faced down. The fillet was glued on top of the truss rod, and the whole assembly clamped underneath a large clamping caul to ensure even pressure and to avoid the clamps marking the flattened surface of the neck.
The assembly was left clamped up over night to allow the glue to cure, and then broken out of the clamps. I then planed the fillet flush to the neck surface using my low angle block plane. I really love the fragrant scent of yellow cedar shavings, and it is a smell that always takes me back to the time I spent in Totnes. Just lovely. At the heel block the fillet currently lies below the surface of the neck and so couldn’t be cleaned up. This doesn’t bother me though as I will clean up that part when I cut the rebate for the soundboard in a couple of weeks.
We’ve now been living in Birmingham for four weeks, and the endless mountain of boxes has slowly been whittled away to only a handful. Which means that I’ve finally had time to not only set up the new workshop, but also to spend a couple of days in there, making wood shavings and progressing the parlour guitar build. What I’ve not had any opportunity to do until now is to blog, but as normal life is slowly re-established, that will all change and I hope to catch up on my blogging shortly. In the meantime, here is a tour of the new workshop.
Before moving in, and while my tools and workbench were still in Bristol, I took the opportunity to do some work on the new workshop to make it a more pleasant environment to be in. The shop itself is a brick and breeze block garage attached to our house, measuring 11 x 17ft, so a good size. There is no ceiling in the workshop, which means that I have the benefit of the roof beams and a large apex roof above me, which gives a very spacious and airy feel.
My first task was to seal the concrete floor, and the wall which I would be facing while at the bench, with a 1:4 mix of PVA glue and water. This is far cheaper than floor sealer, and does exactly the same job of preventing paint from soaking into the porous bricks and into the concrete. After two coats on the wall and floor, I painted the floor with a tile red concrete paint, while the wall got two coats of white emulsion. This job was really to brighten up the workshop, and particularly the wall which will end up in the background of pictures for the blog and for magazine articles. Once the floor paint had dried I put down two rolls of 3mm thick textured rubber matting, which will be more comfortable to stand on than bare concrete, and will hopefully protect the cutting edges of any kimikaze chisels which decide to take a leap off the end of the workbench.
At the far end of the shop I put up a series of shelf brackets, the bottom of which has a shelf for my iPod speakers, glues, oils and sundry items. The rest of the shelf brackets are by way of a timber store, and hold my current stock of furniture stock, mainly oak, pine, and assorted hardwood pieces. All lutherie timber is kept in the house until needed, but the workshop is a fine place to keep more robust timber.
I also built a 4ft wide sharpening station, using two sheets of MDF and some work table supports from Machine Mart. This proved to be a cost effective way of having a rigid secondary table for sharpening and assembly tasks. My go bar station, band saw, and drill press all fit up at the end of the workshop, which means that the main work area is kept free from clutter and I have plenty of space round all four sides of the bench. My Anarchist’s Tool Chest is also readily accessible from its position just to my right as I work, and within an easy arm’s reach of the bench.
This is pretty much the workshop I have been longing for over the past 8 years, and I am looking forward to working here. It is not quite finished yet – there is a paucity of power sockets (only one double socket) and the lighting is not great, but an electrician is coming round soon to fit a dedicated fuse board and then I should have plenty of light and power. This is shaping up to be a very pleasant, and productive space!