router bit for use with templates

[Jedi Clampett]

I am learning to use a router with a template to route neck sockets, control cavity and pickup routes. These are for fender style solid body guitars. So likely needs a bearing that rides on the top so that I clamp template to the top and it follows the template and routes the cavity. Looking for suggestions for size, source and router bit?

[Barry Daniels]

Most commercial template bits are too long for guitar work. Once again I have to promote Stew-Mac products. They sell special short bits just for this purpose. They allow you to make a template from 1/4" stock and that can be stuck to the guitar with double stick tape. The bit is short enough to cut a shallow recess for a control cavity cover.

http://www.stewmac.com/Luthier_Tools/Ty ... _Bits.html

These bits also work for the deeper recesses, because you need to start the cut shallow. I usually route deep recesses in 1/8" layers.

[Gordon Bellerose]

Jedi, there are a few considerations when choosing bits, and making templates.
If I buy a 1/4 inch template, I like to use it to make a thicker one. I usually use 3/4 inch plywood.
The reasoning behind this is that the thicker template gives me more room to work with the short bit when starting a rout, or like Barry said, routing the control cavity cover ledge. I find 1/4 inch too thin, but perhaps that's just me. I have to put spacer blocks under the 1/4 template to start the routs.

As for bits, Barry certainly has the right idea. Stewmac sells some stuff that you may have trouble finding elsewhere.
I'm fortunate to live in a middle sized city (1,000,000 people) with a lot of choices where to shop for tools.
I found some even shorter bits at one of the tool houses in my city.

Bit size is determined by the style of neck you are using. A Strat neck pocket can be routed with a 1/2 inch bit.
A Tele neck pocket takes a 3/8 bit to get the corners sharp enough.
Pickup pockets usually use a 3/8 also.
Make certain to get the guide bearings for each bit also.

[Peter Wilcox]

I use these bits, and I make my own templates like Gordon, but from 1/2" mdf. If you need to go deeper you can remove the template and use what you've already routed as a template.
https://smile.amazon.com/gp/product/B00 ... UTF8&psc=1
https://smile.amazon.com/gp/product/B00 ... UTF8&psc=1

For corner radii of less than 1/4" such as pickup pockets, I drill holes of the appropriate radius in the corners, then route between them.

I also take very small cuts like Barry. I got greedy and bought this bit to do outer perimeters in one cut - tear out guaranteed.
https://smile.amazon.com/gp/product/B00 ... UTF8&psc=1

[David King]

Amana makes some very small template following bits with top bearings.

[Gordon Bellerose]

Here's a link for the Amana bit David mentions.

https://www.amanatool.com/45460-s-carbi ... er-bb.html

[David King]

Here's the 3/8" diameter one https://www.amazon.com/Amana-45475-S-PL ... B001PTZLAO
They also make a 1/4" one but it uses a sleeve bearing instead of a ball bearing.

[Clay Schaeffer]

You can "harden" the edges of mdf templates with super glue to help them hold up better. You can also make a top bearing bit by adding the appropriate sized bearing and collar to a regular non bearing bit. If you use a locking collar above and below the bearing you can fit it to a 1/4 inch straight bit and get 1/8in.radiuses. You must oversize your template to compensate for the off set of the (oversized) bearing.
Some people run the shank of the bit against the template rather than use a bearing bit. This can work, but is sometimes hard on the template, and you must always keep the cutting edges below the template.

[Peter Wilcox]

Some people run the shank of the bit against the template rather than use a bearing bit. This can work, but is sometimes hard on the template, and you must always keep the cutting edges below the template.

That's what I did a few days ago for the first time for a P-bass type pickup cavity with no pick guard to hide the route. I was careful not to put a lot of pressure on the template. It worked well. I used this bit because of its short cutting length, and made several passes:
https://www.amazon.com/gp/product/B00NA ... UTF8&psc=1
Of course it doesn't cut square all the way to the bottom (which wasn't necessary), but a chisel could get the rest.

[Gordon Bellerose]

A lot of good advice in this thread.

A few things that no one has mentioned yet.

1. If you buy a neck pocket template from stewmac, you may notice in the literature that it says "slightly oversize" to allow for thickness of finish.
I have found that they are quite a bit oversize. To use mine I had to build up the edges with about 5 layers of aluminum tape. Once I did that, and got it to the correct size, I used it to make a template out of plywood. Usually, by the time you sand your neck smooth, it will fit a bit loose; enough to allow for finish thickness.

2. Make your neck pocket template longer than the neck pocket itself by half the size of your router base, or more. This gives you enough area to keep the router stable out at the very end of the rout. I actually add 2 inches to that. I use an off cut underneath the end to keep everything nice and level.

3. If you are making templates, make them large enough that you can easily and safely clamp them on top of the guitar, and still have room for your router. In a lot of cases, double stick tape does a pretty good job, but if you can clamp the whole operation to your bench it is that much safer. I find that most of my templates are as large as the body itself.

4. There has been a lot of talk about the bits and bearings. If your bit does not have a lock ring, you can use a small piece of plastic tubing on the shank of the bearing to keep your bearing from sliding up. This could save your project. If that bearing moves while in use it could slide up enough that it misses your template, causing a deeper cut sideways than what you want. (OUCH) I won't bore you with details, but I will say that this comes out of hard experience.

[Peter Wilcox]

3. If you are making templates, make them large enough that you can easily and safely clamp them on top of the guitar, and still have room for your router. In a lot of cases, double stick tape does a pretty good job, but if you can clamp the whole operation to your bench it is that much safer. I find that most of my templates are as large as the body itself.

After some disastrous tape failures, I now screw the template to the body (into cavity locations that haven't been routed yet, or under the bridge), and then I clamp when all the screw locations are used up.

[David King]

There's a whole other type of template system that uses collars that fix onto the router base and thin templates that take up a whole lot less room. You can use regular spiral flute bits that are less likely to burn and tend to last a lot longer with no bearing race to maintain. I do 90% of my cavity routing using this system. You do need to make your template openings .025" or .031" oversize to account for the width of the collar. You would generally use a 5/16" collar around a 1/4" bit. You can buy the collar sets for most routers and you do have to make sure that the collar is locked down concentric with the bit. There are cones that come with the kits that you chuck in the router collet to assure concentricity when setting up the system but I haven't found it necessary to use them. I turn my own custom collars that have a smaller .050" offset and mill all my templates accordingly. My collars stick down only 3/32" of an inch so I can use 1/8", 3/16" or 1/4" templates which I make from Lexan/polycarbonate.

If you are experiencing tape failures or templates shifting you might want to change up the type of take you're using. The old fabric lined carpet tape is not suitable and it allows way too much lateral creep. Look for a 3M transfer tape that's 2mil or less. You can also use a stronger assembly tape like this stuff: http://www.amazon.com/dp/B00JL8OM5Q/ref ... 5Q5142078/ but it can cause tear outs in softer wood.

[Todd Stock]

ShurTape fiberglass reinforced carpet tape is excellent, and easily releases even in on large stuff like rosettes with a little naphtha.