Template cutter bit against metal template?

[jay5]

Is it a bad idea to run a template bit against a metal template? Since I dont have a bandsaw I have decided that the best method available to me is to rough cut the neck shape with my crappy jigsaw and then use a straight edge (template) and template router bit to accurately cut the fingerboard part of the neck straight. I would then cut and sand the headstock shape by hand. Obviously this method would require a very straight template. I was thinking of getting a piece of square aluminum for this. Would I be jeapordising my bit by doing this as the cutting edge would have to run against the metal until the bearing could run against the neck itself. Thanks!

[GregP]

I only tried using a router for the first time today, but my immediate reaction is:

Bad idea. Any number of horrible things could happen, regardless of whether it's a table or plunge router (you don't specify). The slightest tilt of either the template or the router, and you've got high-speed metal meets metal which at minimum will trash your bit, and at worst could cause serious (and permanent) physical injury to you. Using power tools is a dangerous enough proposition in itself (I'm not paranoid, I just mean -relatively- speaking, compared with most people's day-to-day activity) without adding this highly risky extra factor.

You may want it to be as exact as possible, but even with a router and template, you're probably going to give yourself 1 or 2 mm of 'play' at minimum, in which case you'll STILL be bringing it to exact shape using hand tools and/or a sanding stick (or equivalent) of some sort.

A router is still a great way to go, but I just used a piece of MDF and it worked fine... I've seen templates made from plywood, too. I'd suggest that if you REALLY want to use a 'near perfect' template, you might as well just buy one. Otherwise, there are other options to consider before using metal.

Greg

[krazyderek]

i used a metal straight edge for my flush trim bit to follow when tappering a neck last week, however i did this on a table mounted router so that i could line up the bearing with the straight edge and pretty much guarantee that the cutter would never touch the metal (yes this took some precise setup work) but once it was all locked down everything went smooth.

[jay5]

Derek, could you elaborate on how you set up the router to ensure that it wouldnt hit the metal? I have a router table and was just curious about your method. Thanks

[krazyderek]

notice there's a small gap between the metal straight edge and the wood, it's held to the wood with black bouble stick tape.... basicly just leave the cutter a bit shy of the top of the wood, cause there's usualy a gap between the end of the cutter and the bearing, that space gives you some room to play with the height (ie alignment) of the bearing with the metal edge..

[jay5]

Cool, got it. Thanks!

[Myka Guitars]

I use metal templates sometimes. They work great because they are so stable. Go with the method that krazyderek mentions and you should be fine. It's how I usually use templates with the router table. It's my main tool.

As a side note, you can route aluminum without a problem but don't take more than 1/16" on a hand operated router table and try not to route more than 1/4" thick almunimum. Cut the aluminum with a bandsaw very close to the shape first before routing it with a template and router table. I mention this because I have made aluminum templates out of my wood or MDF templates before by routing the aluminum to shape with the router. I did this because I use them all the time adn wanted to make them out of something more durable.

[krazyderek]

cool, do you have one bit set aside of routing metal? or does it really not wear on the bits at all more then wood?

[Myka Guitars]

If you go slow it shouldn't wear the bits too much but I would think that it does wear more than wood. It is harder. I use the same bits for both wood and aluminum.

[jay5]

Interesting Myka. I only have a cutter bit with a top mounted bearing but the method described would still work. I will just need to have a very level surface for the router to run across. I was also thinking of trying to find some acrylic plastic as the strait edge. That way if I did screw up I wouldnt hurt the bit too much.

[balooka]

I use 5mm stainless steel templates to rout about any cavity in my guitar. I use several same sized bits that only differ in cuttinglength (depth?). I had one bit that was trashed when titled to the steel and the solution was pretty simple. I bought some bearings that were 4 and 2mm wider than the bit, cleand out the cavsity as much as i could, leaving about 1-2 mm clearance from the template. Then I put a brearing on the shaft, the same size as the bit itself (usualy 2 to cover the length of the shaft so it wont slip up) and go straight to the edge. Removing alot of wood before trimming it flush is the way it works for me.

I don't have a tablerouter so all this is done with a plungerouter, takes a bit more time to complete, but works good for me.

HTH

JP

[GregP]

I'll gracefully eat my words and file this thread in the 'cool ideas for a future project' slot instead. Already thinking about that aluminum. ;-)

Greg