The North Buttress of Colchuck is an outstanding feature on the peak. I personally think that it is more of a ridge than a buttress, but it is overall wide enough to provide numerous variations for nearly its entire length so one can vary the difficulty of the climbing to suit their ability, mood, and the weather. If climbed as per Beckey who recommends staying up to 200 feet west of the crest, the climbing is Class 3 & 4. If one stays on or near the crest the climbing is very enjoyable easy Class 5 - up to about 5.4. From most places, it should be possible to traverse to the Northwest Route, which is a scramble.
The North Buttress Couloir Route puts one out on the North Buttress at just about where the steep climbing starts, thus avoiding the lower scrambling part of the route and providing a much more interesting start to the climb.
Reach Colchuck Lake as per the main page. (About 4 miles of trail).
The lower buttress is attained from the south end of Colchuck Lake via a shallow gully leading to a col or notch low on the peak.
Colchuck Glacier is visible from the lake and easily reached over talus or snow depending on the season. (less than a quarter mile). The base of the North Buttress Couloir is obvious from and easily reached from the toe of the glacier.
If climbing the lower buttress, it is reached via a shallow gully leading to a notch low on the peak. The lower part of the route is scrambling - easiest just west of the crest. When the steeper upper part of the route is reached, there are numerous options depending on what level of rock climbing the group wants to do. Staying directly on the crest is the most difficult with pitches up to about 5.4 if desired. Beckey recommends easier terrain up to 200 feet west of the crest.
There may be steep snow in gullies and pockets early in the season. With care and staying well west of the crest, the route should not be harder than Class 4.
See the North Buttress Couloir Route description for this more interesting variation in reaching the upper steep part of the buttress.