Flush trim template bit

[creativegrain]

I'm wanting to invest in a good quality template bit. My router is mounted in a table. Is there a preference to where I should want the bearing? Below the cutter so when mounted on the table its above the cutter, or vice versa? I'm just doing pretty basic stuff like routing out templates of chopping boards etc. I tried searching but couldn't really find a recent consensus.

[Thylacene]

My preference is for the bearing on the end of the bit, so when the work is on the table, the bearing is at the top and the template is stuck to the top of the work piece, if it is at the bottom, you end up with a spinning blade where you don't want it. I use a 1/2 shank, 1/2 inch bit that has a 50mm cutting face, I think it is just a Bunnings job, but I may have scored it at a woodwork show.

[elanjacobs]

Definitely bearing on the end.

[spokeshave]

+1 for bearing on the end when it's used on the table for the reasons outlined above.

[Ratbag]

An end bearing will help you see how well you're following the template. Plus it can be interchanged with other diameters for offset work.

[malb]

If you are doing fairly simple stuff where the grain is not changing direction relative to the template, a bearing on the tip is fine. Once the template contains concave sections, or the grain of the material gets cranky, sooner or later you end up cutting 'uphill' and get chipout etc.

A solution is to use a double bearing bit, with a bearing on the shank and one on the tip. Then you set up as though you were using a tip bearing, and fix the template for maximum safe work in that mode. Route what you can, stop everything, adjust the bit height, fit some extra guarding to cover the tip bearing and the now lazy part of the bit, flip the work over so the template is riding on the table, start up and complete the job, now routing downhill or with the grain. No chipout or grief, no moving and realigning the template, just adjust bit height and guarding and flip the job.

Double bearing bits are not common, or dirt cheap, but they are definitely a worthwhile extra if you work with cranky grains or odd shapes.

[Kuffy]

I would say...depends on the situation. I use both. If i am just making a one or two pieces, probably never to be made again, then i dont want to goto the hassle of making a decent jig. All i will do is rough cut the shape on the bandsaw (rough meaning, pretty damn close but still in need of refinement) sand it smooth and double sided sticky tape the template to the timber stock to be shaped using a flush trim bit with bearing on the end of the cutter.

if the plan is to make many of the same item, such as serving tray end panels (see picture below), i will goto the trouble of making a decent jig for it. The timber stock will be clamped to the top of the jig with the bearing running along the template which is below the timber. this is extremely accurate and the fastest way I know of which is within reasonable reach of a hobbyist or small shop. this method is fantastic because its so quick, I can cut down the grain on both sides of the hill simply by unclamping and flipping it over only cutting half of the cut each pass.
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[safari]

Carbi-tool sell a bit with a bearing at each end at a pretty good price. Works nicely for me.

[Template Tom]

Carbi-tool sell a bit with a bearing at each end at a pretty good price. Works nicely for me.

Working with template Guides it is possible to complete the slot for the base of the tray358366 and the slot for the sides of the tray completed with the router in the plunge mode inserting the material into a simple jig and constructing the templates to produce the various shapes with the material inserted in one position and removed when all the processes are completed
Tom

[Template Tom]

Here is an introduction to the use of template guides for those who may be interested in how the guides can be used360588