Thread: Why do I need an insert plate?

Originally Posted by OtakiriLad

I am about to build a decent router table and have been researching for plans, suggestions and reviews from various places on the net including this forum. One of the concerns is to make sure things are ‘rock solid’ to ensure there is minimal play in the router bit above the table.

From what I have seen most, if not all, insert plates have the router and any lift mechanism screwed to the plate which is then dropped into a routed hole that matches the plate size. This plate is not fixed and relies only on the weight of the router etc to not move during operation.

Why not screw the router and lift mechanism directly to the table and remove any risk of plate movement? Or am I missing something?

Cheers

Mine is not screwed down and it never moves, the weight of the router and lift hold it down and anyhow when you put your wood on the plate they don't move relative to each other as the router and plat are joined.

SB

There a quite a few table designs on the web which do not use inserts and mount the router directly to the underside of the tablebut they tend to be small tables, or rely on having the top tilt up to at least 45 degrees for bit changing access.

I suspect that inserts became popular in the US because of their propensity to use fixed base routers, and lifting the router and insert out of the table made bit changes much easier. They are starting to discover plunge routers for table use, but even modern through table change plunge routers do not provide enough lift for convenient bit changing when the router is mounted 20mm below the surface.

A further consideration is the use of insert rings with an insert to keep the clearance between the bit and the insert/table opening to a minimum. Insert generally have an opening that can accomodate larger bits like panel raisers, and a set of 3 or more insert rings that mount in the opening to close it to a tighter fit around the bit. This is difficult to do with a direct mounted router. The concept of using the smallest opening that will clear the bit is similar to using a zero clearance insert with a table saw, it provides maximum support for the work to minimise chipping, and limits the possibility of the work snagging on or travelling through the opening in the table or insert.

There are several reasons for using a router plate with inserts, a few of which have been mentioed above.

Another reason, not yet mentioned, is that the average router table tops are 30-38mm thick and if you mounted your router directly under that you would lose a lot of router travel.

The average router plate is around 10mm thchk so you have much more usable router travel.

My router plate is a snug fit in the recess in the table top and doesn't move at all, can't see any reason to screw it down.

Many thanks for the comments. I might try and experiment with a direct mounted lift and rings and if that doesn't work I can always cut out a hole for a plate.
Cheers

I wondered that too.

Considering the ridiculously high prices on setting up or buying a router table, the plate seemed to be superfluous.

It appears that it is really just to facilitate router adjustments and bit changes. I do know that it is best to consider a metal plate, as there is less "give" in them, but I am still shocked by the expense of setting up a router table, especially the lift.

I use a Kreg insert which screw fastens to corner attachments which have levelling screws.
These corner attachments are screwed underneath the table in the cut out in the table

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I made my own insert plate out of a bit of scrap 8mm aluminium plate. It's screwed to the top with countersunk machine screws and threaded screw inserts. I used masking tape to take up any misalignment in the height. Very happy with it.