A few years ago, I whipped up a primitive crosscut sled in a few
minutes. It was ugly, but accurate and extremely handy. My biggest
complaint was the capacity - it was limited to 24", which was very
frequently inadequate. I've been wanting to build a better version for
quite a while - so I finally got to it last weekend, based on the Precision Crosscut Sled
design from ShopNotes #99. The original had 18" cross-cut capacity (42"
with extension). I already knew that 18" wouldn't be enough, so I
modified the design to give me 36" capacity, which I think will handle
about 90% of my needs. I used a different design for my extension which
gives me a 66" capacity - I hope that will cover 99% of my needs.
The result is this:
The original design included a sliding section for zero-clearance with
various blades. I can confirm this design works nicely - as shown here
with my dado blade:
For longer cuts (36"-66"), I attach my extension. It consists of a rail
that rides behind the fence, a clamp that rides the fence and a
shelf/stop to support the end of the board. Here is a slighly blurry
picture that shows it cutting some trim to about 5'.
When using the extension, the length is set using a gauge on the lower rear of the fence:
I hope you like it!