Source
r/Luthier•
Carter127

Tips for getting smooth curves on templates/bodies

I'm pretty new to a building guitars without using premade bodies and necks, I recently bought a router and am trying to make body templates but I'm having a hard time getting the curves to be even. They are more like a series of lines on the template and it comes off even worse once I route the body with a flush trim bit.

Is there any tools you guys use to make getting even curves? I've found using 80 grit sandpaper takes a long time and doesn't get even results on my 1/2" MDF templates. Is this just a practice thing or is there a better way to go about it?

I'm happy to buy more hand tools, as I quite enjoyed restoring my first plane recently. Would something like a flat or round bottom spokeshave help? a compass plane? Should I be using a different material than MDF for my templates?

Side question, does anyone have any recommendations for a great router bit for routing bodies? I've had a hard time finding good top bearing spiral bits that are long enough, should I just be using bushings instead? I'm happy to spend a lot on something that will last.

Posted Oct 15, 2020, 3:08 PM UTC

25
tarabash•

Oscillating spindle sander does magic for me, but that only speeds things up a bit. 80grit and patience did it for me for my first templates (not guitar related). Draw it on mdf, cut with band or jig saw and sand sand sand.

6
cromag5150Luthier•

Make your preliminary templates (masters) out of quarter inch MDF vs half inch. It’s lower mass is much easer to sand and shape. As has already been mentioned a spindle sander works great for concave sections. Mark your work either by directly drawing your lines or better yet, by attaching a full sized printout of your intended template directly to your piece using spray adhesive. If you don’t have a spindle sander some sand paper on anything round will work. For convex sections I use a 12” disk sander. Any flat sanding block will also work.

Take your time and be precise. Be methodical. Once you have your quarter inch Thick master completed use a pattern router bit (with a bearing) to make a working copy out of half inch MDF. Never use your master template for anything else but making another working template.

4
Carter127OP•

1/4" mdf first is a great idea, I will definitely do that for the next one.

2
[deleted]•

You'll just need to sand the template. Dual action oscillating sander for the win. Get one if you don't have one.

A bushing will be best. You can find some top bearing bits, but a router bushing will be much easier.

Remember to try and consider grain and how the router bit spins. The end grain, like the horns and butt if the guitar, will try their hardest to splinter and chip out. Climb cutting can help but can also be hazardous. Conventional is probably best for end grain to not pull the wood out.

I run an industrial router for my career. I could to go on forever about routing and wood. There's so many nuances to it, especially using real woods.

2
JimboLodisCPlayer•

I'm having a hard time getting the curves to be even

So what's your current method?

1