Working with routers and router tables is often one of the most frightening tools for new users and often one of the most mis-understood by more seasoned woodworkers. Part of the reason for the fear and misunderstanding is that this tool is pretty unique ... the router spins at speeds that makes one think it could easily lift-off the workroom floor and if you are not careful, it can ruin a piece of wood on you pretty quickly or fling it out of your hand before you know what happened.
The truth is, working with routers and router tables is not really not that daunting when you have a baisic knowledge of the tool and an understanding on some of it's principals of operation. The first thing that anyone using a router will do is to decide on what bit they want to use. Many of todays routers like Bosche, DeWalt, Makita and Freud will use both 1/4 inch or 1/2 inch shank router bits and will include both 1/4 inch and 1/2 in collets with the tool. The collet is the name for the chuck or bit holder for the router. When installing any bit in a router, it is important that it be seated properly. This means pushing bit all the way into the collet as far is it will go, then drawing back out about 1/32 of an inch. This draw back is to allow for heat expansion. Router bits can heat up pretty quickly while cutting through wood and they need a small bit of area to expand into at the bottom of the collet. Next the bit needs to be tightened firmly. This does not mean you need to crank the nut so tightly you damage the machine, but it does need to be tight enough that the bit will not spin inside the collet or have any chance of coming out.
Once the bit is installed and the router is seated in the router table, the next thing to look at is the fence ...
The fence on many router tables does not run perfectly parallel to the bit. This means that the fence can be askew of the bit and still produce perfect cuts. This is because everything to do with a router table is centreed on the bit. The fence is adjusted according to bit so because the bit is round, it doesn't matter if the fence is parallel to anything or not as long as it is adjusted according to cut required from the bit.
To further clarify this, if you look at many router tables, you will see what appears to be a mitre gauge slot like that on table saws and band saws. This slot is not a mitre gauge slot, it is a featherboard slot. This is because it is NOT recommended to use a mitre gauge on a router table in conjunction with the fence. Just like you would never use a mitre gauge with the fence on a table saw - so should you NEVER use a mitre gauge on a router table in conjuction with the fence. The ONLY time to use a mitre gauge is when the fence is removed - on ANY tool.
So what we use on a router table instead of a mitre gauge is a wooden push block of suitable size, usually 4 inches wide 3/4 inch thick and about six to eight inches long is sufficient. This block is used to push smaller pieces and cross grain pieces on the router table. It is very important that the push block have 90 degree corners, otherwise your work peices run the rist of not havint square cuts particularly if they are shorter cross grain cuts such as in rail and style doof frames.
The final set-up concern is the the height of the bit. This is normally adjusted through height controls on the router table, or if you have a router lift attached to your router table. Once the fence has been adjusted properly and the height of the bit is set, you are ready to run a test piece of wood through the router.
Be sure not to take too bit a "bite" of the wood, particularly if you have a large router bit installed. You may need to make a few passes, taking off a smaller bit of wood each time until the full cut is made. With larger bits you will also want to slow the speed of the router down somewhat.
Now that you are ready to run wood through the router table, the next important thing to note is the direction. Because the bit of a router runs counter clockwise as you look at it from the bottom of the router, the wood you push through the router table MUST be pushed from right to left. If you push the wood through from left to right the router bit will often "grab" the wood and fling it through the router table. Just like with a table saw you always feed wood into the opposite direction of spin the bit or blade.
The best way to ease your way into working with a router is to go slowly, ensure you have good eye and ear protection because that helps to eliminate outside distractions, and just start of with small short cuts. Once you have that confidence, you can start working on larger works.
Copyright - Colin Knecht