Showing posts with label Forstner bit. Show all posts
Showing posts with label Forstner bit. Show all posts

Sunday, May 27, 2007

Routing--Stage Four

It's perfect guitar-making weather here in Chicago and I took the opportunity to get some real work done and rout the pickup and control cavities. I was also hoping that I'd annoy the neighbors enough that they'd leave their backyard barbecues to come yell an me to knock it off, thusly giving me an excuse to rip their faces off w/ a router, but no such luck. I don't have anything against them but I just have a thing w/ routing faces. What can I say?

For the pickups, I taped the template to the mahogany and cleaned out the spots for the rout w/ a Forstner bit. Unfortunately, my drill press isn't big enough to do this sort of thing so I did it really carefully w/ a hand drill. I wrapped a bit of tape around the bit to use as a depth guide:


This trick works well enough for drilling ordinary holes but not so great w/ the Forstner bit unless you want to spend all day wrapping tape around the bit until its actually thicker than the head. I ended up pretty much just eyeballing it. It worked fine but it did make me nervous. For whatever reason, I decided to do this part inside and I have a feeling that I'm going to wallowing the strange sawdust a Forstner bit produces which looks for all the world like a big pile of pencil shavings:


There was quite a bit of cleanup to do w/ the router once I was done. As I've mentioned, the holes in the templates are jut barely big enough to squeeze the pickups in so I set up my router w/ a bit that was slightly larger diameter than the bearing that follows the template:


This actually ended up taking out a little bit of the underside of the template too, which isn't a big deal aside from the fact that MDF is hard as a rock and you really gotta hang on to keep the router from flying out of your hands:


The pickups fit in there really well. I didn't get it absolutely perfect but you really gotta look at it to see anything wrong:


The pickup in the picture is a tilted because it's sitting on top of its lead wire, which brings us to the next step: drilling the hole to connect the pickup cavities. I did this using a drill bit so long it's almost comical:


Seriously, it's about a foot longer than I need but my local mega mall of mega home supplies only has normal length bits and super long ones so I was forced to go w/ this. Drilling the hole was easy, you just start at the neck pocket and drill right on through. I forgot to take a picture while I was doing this but this should give you the idea:


The end result looked pretty good. I didn't get the hole quite straight so a bit of the bottom of the bridge pickup cavity was gouged out by the drill bit. I'm not gonna worry about it but next time I think I will try to drill a guide hole first:


W/ that taken care of, it was time to get onto the more difficult task of routing the control cavity. You would think this would be less critical--and maybe it is--but I wanted to set it up so that the control cavity cover would be recessed to be flush w/ the back of the guitar, which added a lot more work. First, in order to get the router so that it didn't cut too much away, I had to shim it up w/ scrap pieces of MDF. I'm gladI bought those extra clamps now:


I took off about an eight or sixteenth of an inch of wood for the area that's gonna be the rim of the control cavity:



I had started to remove the wood in the middle but realized that it was just gonna be removed anyway when I drilled out the excess wood w/ a Forstner bit. Thankfully, this time I could use my drill press and it came out much nicer:


I should note that I drilled the holes for the controls before hand so I could test the thickness of the top by putting the knobs in there. I also figured I could use them to get the template centered well, which didn't really work but whatever. So that I didn't rout out the wood that was to be the rim, I use the reverse of what I did for the pickups and made the template bearing larger than the bit so it left a little bit of wood untouched . In the end, I didn't do that bad of a job of it:


It's really close but even though that one hole is so close to the edge the pot still fits in there, albeit just barely. It's good luck rather than good planning but I'll take it. I ended up having to repeat the first step to get it so the plastic cavity cover to fit but I got it in the end:


The one last thing I wanted to do was drill a hole from the pickup cavities to the control cavity. This is where my lack of planning came back and bit me in the ass. Basically, my plan was to use a hand drill and just drill right in:


This would have worked great but the relative locations of the pickup cavity and the control cavity were such that it was pretty well impossible to get the angle right. I said a Hail Mary and just went for it. The drill bit came out of the rim of the control cavity:

It will be covered up by the plate so no big deal but I'm still sort of cheesed at myself for not seeing it coming. I drilled it out a bit and will clean it up w/ a Dremel or something at a later time.

And here is my little lady so far (looks nicer here than in person):

Tuesday, May 22, 2007

Routing--Stage Three

I turns out I should have been more careful drilling the holes for the screws to attach the template to the body; they were two small and one of the screws broke off when I tried to extract it. I had to bend the thing and unscrew it w/ a pair of pliers:


For the rest of this project I'm sticking the template to the body w/ carpet tape. It's almost too strong for the job. I was worried the tape would pull chunks of mahogany out of the body when I pulled the template off of it.

I finished up the neck pocket today. The first thing I did clear away as much wood as I could using a Forstner bit in my drill press to save wear and tear on my router and bits. I don't have a proper table built yet so I ended up clamping the template I wasn't using to it and supporting the body w/ that as I worked on it. It turns out that there is indeed a very fine line before clever and stupid:

Worked like a charm (somewhat to my surprise). A Forstner bit, by the way, is sort of an improved version of spade bit. It drills wide holes w/ a relatively flat bottom. It looks almost like a router bit:


I set the depth and drilled away until I had most of the wood cleared. The depth gauge on my drill press isn't too accurate so I did a few practice holes on scrap and double checked w/ a small ruler to make sure I didn't drill too much. When I was done, it ended up like this:


From here it was a simple job to clean it out w/ a three-eighth inch straight router bit and the template following guide. I worked very slowly and carefully and only ended up w/ a few minor mistakes that are (hopefully) mostly cosmetic and will covered up when the neck is attached anyway:

Ultimately, the neck fit in a little less tightly than I'd hoped but it does take a nice picture. Not too shabby for a first go at it, I say:


I realized another mistake I made which was not making sure the edges of the template were completely square w/ its top. There was a bulge along the in the middle of the template's edge that held the neck tightly but the template follower followed the top of the template rather than the middle so I routed out more than expected. It's close enough for rock and roll though. I'd imagine it's only marginally less stable than a standard tele neck pocket (which doesn't have support on both sides) and once I get some finish on there, it should fit in even better. If worse comest to worse, I will just insert shims on either side of the neck to keep it from going back and forth. The depth of the pocket and the very end of the heel are right on so there's no reason it shouldn't be stable in the direction the strings pull on it, provided I get the holes drilled properly.