Router Cutter, profile routing.

Springywheel

When profile routing a guitar body or neck, how much is safe for me to cut off at once, vertically? In other words, how much of the cutter’s face can be exposed to the body?

The reason I ask is because my template is thin - around 6mm thickness - so by using a 1/2” cutter length, the majority of that will be cutting at once with the bearing up against the template. Would this be ok or should I use a 1/4” length cutter just to be on the safe side?
Obviously cutter diameter is another matter - I plan on cutting as close to the outline as possible beforehand with a bandsaw. What i'm worried about is cutter depth. I want to avoid having to cut thicker templates. 

Roland

This came up on TDPRI forum a couple of days ago. The advice there was: 

1. Use your template as a Master, and store it outside of the workshop so you’re not tempted to use it except...
2. Cut a working template from your Master.
3. Cut your body using the working template.

As regards how much to trim. Width of cut I’d say 1/16” at a time. With some Timbers you can get away with more, but you risk tear out. Don’t forget to cut it the opposite direction to the way the router spins.

Depth wise you’re unlikely to be able to cut a whole body in one go. With a reasonably long bit, say 20 to 25mm, you can cut halfway using the template and the rest running along the cut surface. Depending on the design your router you might need to have two router bits, one top bearing and the other bottom bearing, so that you can cut the second half from the other side.

greggreg66

I have a 12mm tall "top bit" template trim cutter and have the best results when I use that in shallow height passes. It's definitely worth buying a shallow depth trim cutter like this so you can do small passes to avoid tear out. You can buy really shallow template trim cutters from Wealden, they're so good.