[Dirk Herr-Hoyman]

I've been using a Bosch 1181 router table for a couple of years now. While mostly it's ok, I am a bit fustrated on setting the fence distance to the bit. There are 2 knobs on each side and a cheesy distance gauge. It's hard to get the distance dead on with out some trial and error.

Recently, I was somewhat foiled when cutting a sliding dove tail joint using a 14 degree 1/2" bit. The side where you cut down the middle is fine, it's the other side where you take 2 cuts on each side of the "pin" which is tough. You are supposed to cut a little bit off, on each side, until it fits. This is like 1/32 or even 1/64 for a cut. That's hard to get set with this type of fence. I am tapping just a wee bit, but it's hard to do on both sides and know how far you've moved it. I was wondering if there are suggestions for a better way to go at this.

TIA,
Dirk Herr-Hoyman

 

[Dirk Herr-Hoyman]

Welcome to the forum, I'm not an expert, we'll see what the more experienced people say.

What I'd try, the fence doesn't have to be perfectly parallel to the front of the table, when you want to make a tiny adjustment you can loosen the knob just on one side and move that end.

How far is the bit from the fence and what do you have to measure the distance accurately?

In this case, it's about 1/4". But, there's enough length on the cut, about 1", that I do need it to be parallel.
And it's 2 cuts, which do need to be parallel for the joint to work right.

 

[Dirk Herr-Hoyman]

Before I changed tables/fence I would measure the distance to the front of the table from the far left and right side of the fence. If it was tight bump it back a hair and measure, make another cut until you get the distance right.
I also would mark a pencil line on the table where the fence is and use that as a reference point.

The problem I'm having is doing a bump for just a hair. That's being hard to get right.
The way the fence locks in, with a long screw bolt, doesn't give consistent pressure so my
bumps move the fence different amounts. Unlike the fence on my tablesaw, which has a screw
mechanism that move very precisely.

 

[Dirk Herr-Hoyman]

I have the same table. Not the best one out there but I've had it for a long time and it works. I've gone through several iterations of how to adjust the fence. The method I use depends on how far the fence has to be from the bit. For short distances I use a Wixly mini height gauge like this one Wixey WR25 3" Mini Digital Height Gauge - Saw Gauges - Amazon.com I use it to set my bit height and lay it on the table with the "feet" against the fence and gauge against the front of the bit. I can then move the fence forward or backward very precisely as long as it's in the range of the sliding gauge.

For larger distances I use a somewhat similar method but it's a little kludgier. I put a 6" metal rule across the opening in the fence. (You could also just slide the sides of the fence closed but the rule if faster). I then lay my digital caliper with the slide extended next to the bit and touching the rule and use some blue tape to hold it down. I can them move the fence and see the change on the caliper. This isn't quite as accurate as the first way since the measurement is next to the bit, not from the middle of it. However, I personally haven't had the problem since I've never had to adjust the fence a miniscule amount for a large diameter bit. As I said, a bit kludgy. And, needless to say, I always make test cuts along the way with a piece of scrap that mimics the work piece.

If you really have a need for super accurate cuts, which it sounds like you do, a micro adjuster is probably the best way to go. I haven't looked at any to see if they'd work with the 1181.

Using a better gauge is a good idea. Thanks for the suggestion.