Ceramic Bandsaw Guide Blocks — and the Amazon Alternative

Bandsaw guides do one job: stop the blade deflecting sideways and backwards as the work pushes against it. The closer they support the blade to the cut, the straighter it runs.

With steel guide blocks there is a limit, and it is heat. Steel against a moving steel blade generates friction, and a blade running against steel blocks heats, loses temper and dulls at the set. So steel blocks must be set with a small gap — typically the thickness of a piece of paper — and that gap is slop the blade can move in.

What non-metallic blocks change

Graphite-impregnated blocks like Cool Blocks, and ceramic blocks, can be set in light contact with the blade. They are self-lubricating enough not to generate damaging heat, and soft enough not to wear the blade’s set.

Setting them actually touching removes the gap, so the blade cannot deflect at all between the guides. On resawing — where deflection shows up as a cut that wanders off line through a tall board — the difference is obvious.

Setting them up

Close to the blade, front to back: the blocks should stop just behind the gullets, never contacting the teeth. Blocks that touch the teeth destroy the set within seconds.

Then in light contact laterally, with the thrust bearing set just clear of the back of the blade so it only engages when you feed.

They are consumables

Non-metallic blocks wear. Dress them flat on sandpaper occasionally, and replace them when they are worn past adjustment. That is the cost of the design, and at this price it is not much of one.

Fix the basics first

A bandsaw cuts badly for three reasons before guides: a blunt blade, insufficient tension, and the wrong blade for the cut. Guides are the last five percent. Tension the blade properly, fit a sharp blade with the right width and TPI, and then set the guides close.