Newb Question. Router Template?

[fjl]

http://www.amazon.com/gp/product/customer-reviews/B000063XTX/ref=cm_cr_dp_pt/103-9327946-0211857?ie=UTF8&n=228013&s=hi

How exactly are these used and what are they supposed to do? I really don't know what their purpose is... Sorry, I guess I'm just a total newb. 

[Rusty]

Template guides or bushings are used to follow a template.

This page should explain it a little better than me.

[moriartyds]

The link Rusty provided looks pretty complete.

The shorthand version:
 - The template guides you linked, attach to the router base (method depends on model) and surrounds the router bit.

- You create a template that is slightly bigger than the final shape (see the section on critical distance)

- Clamp your template on top of your final piece.

- Route letting your template guide follow your template.  The guide will ride along your template (while preventing the bit from routing out your template).  The part of the bit that is exposed below the bushing cuts the bottom piece out.

edit:  if you're confused about how to make a template, check out the top/bottom mount joystick jig thread stickied above for an example.

[fatfingers]

Template guides or bushings are used to follow a template.

This page should explain it a little better than me.

So why would a person use one of these instead of a template cutting bit (I think that's what they're called?)

[ScottS]

So why would a person use one of these instead of a template cutting bit (I think that's what they're called?)

Template or pattern bits are straight cutters that are only designed to route along the side of a workpiece.

Template guides (a.k.a. bushings) work with a larger number of bit types (e.g. dovetail, v-groove), which gives them more flexibility. There are kits, for example, that combine a v-groove bit with a guide bushing and allow you to route letters in the top of your work. Move dovetail jigs also use template bushings.

[Rusty]

Yeah, what Scott said.

For many more common purposes, such as building a joystick recess jig either a template bit or bushing would work.  Bushing guide sets allow for more flexibility in depth of cut and template thickness.  You don't need to buy a special bit for each different jig you need.