Making Templates for Routing

[Jerry Murray]

If the bearing on the router bit is 3/8" I am assuming that the template would also need to be the same thickness.

Is there a preferred plastic for making templates? I'm thinking about using plexiglas. Is there anything in particular that you use?

[Lee Schierer]

I've made templates from lexan, plywood and hardboard. Nearly anything that holds it shape can be used. The investment in the template will depend on how many times you intend to use it. For a one session template, I tend to make them as inexpensively as possible to get the job done.

[keith ouellette]

If the bearing on the router bit is 3/8" I am assuming that the template would also need to be the same thickness.

Is there a preferred plastic for making templates? I'm thinking about using plexiglas. Is there anything in particular that you use?

I'm not sure I understand the question. The 3/8 would be the diameter of the bearing and would have no "bearing" on the thickness of the template. Unless you are saying you bearing is 3/8" high. But I don't think it would matter. The template can be any thickness as long as you are using a straight bit and enough of the bit shows past the template to make your cut.

[Tom Hargrove]

The type of template depends on the type if bit you are using, (top bearing vs. bottom bearing) and the thickness of the wood that you are machining. The height of the bearing and the thickness of the template do not need to be the same. I think you will be OK if at least half of the bearing is riding on the template. You can use 1/4" template material with a 3/8" bearing without a problem.

I generally use MDF for templates, unless the template is going to be used over and over (and I mean more than a hundred) times. If the template is going to see more than occasional use, you can harden the edges of the MDF with thin bodied CA glue (superglue). I use two coats of CA. The first and sometimes the second application of CA will soak right in. When it hardens the edge is quite strong, at least for the purposes of having a router bearing rub against it. IMHO, plexiglass does not offer any benefits over MDF; it is more expensive, and more difficult to work with. MDF can be repaired if the router bit goes where it should not. Plexiglass is more difficult to fix.

When I worked in a production shop, we built jigs/templates/fixtures using phenolic sheet for the parts that came in contact with the bearings or pins (on an inverted/overarm router), but only when we were machining thousands of pieces. Otherwise, we used MDF.

[Greg Hines, MD]

I make templates out of 1/2" MDF, and have never had problems with it.

Doc

[Jerry Murray]

Ok let me add some more details.

I am making pistol grips. The template will mirror the original grip and hopefully I'll make many sets and be able to use a 'master' template. The grips themselves will be a final thickness of between 1/4" to 3/8" depending on the model.

I have in mind this (http://www.leevalley.com/wood/page.aspx?c=2&cat=1,46168,46171&p=51851) bit. I don't need a very intricate cut, just something to put me about 1/16 off the main outline and I'll finish with files/sanding etc.

I would like the material used as a template to be fairly easy to cut. USP sells some fairly inexpensive poly sheeting in various thicknesses.

[Gene Howe]

Second the use of MDF, with a CA reinforced edge, if needed. A second choice would be 1/2" Baltic Birch or Apple ply.

[Peter Pedisich]

have had good results for years with 1/4", 1/2" & 3/4" mdf. thickness depends on cutter length and where you need cutting edge to be.

soak edge with shellac for hardness.

offset router base from Pat Warner makes template routing precise and enjoyable.

[Jamie Buxton]

A good thing about MDF for curved templates is that it can be sanded/filed/shaped fairly easily. It is soft, and there's no grain to try to lead your tools. However, it is still dense enough that the bearing doesn't dig in.

[Jerry Murray]

Thats why I love you guys...ok I'll go to HD or Lowes and see what they have in 1/4" mdf.

[scott gunnell]

For some templates that I have made I made it out of MDF first and then transfered the shape to UHMW PE for longevity. The MDF is easy to work and cheap to replace if I screw up, and the PE lasts forever. But, I will also make a one timer out of just about anything. I don't reccomend using 1/4" Plywood for pattern routing (not much edge strength).