Trowel Blades & Pans

A float pan contacts the concrete across its whole face, so the weight of the machine is spread over thousands of square centimetres. Contact pressure is low and the tool behaves like a huge rotating float: it levels the micro-profile, closes the pores and brings cement paste to the surface, which is what the later passes work with. There are no edges to score, because there are none.

A blade contacts the concrete along a strip a few centimetres wide, set at an angle. The same machine weight now acts on an area dozens of times smaller, and instead of levelling it compacts. This is the stage that produces surface hardness and sheen — and the stage that cannot be brought forward, because on soft concrete the blades leave grooves that no later pass will close.

So the order is always the same and it is not a matter of preference. Pan first, blades second, and their pitch rises with every subsequent pass. Tooling is not an accessory to the machine — it determines which stage the machine is able to work at.

A pan is larger than the circle swept by the blades because it has to overhang them — otherwise the blade edges would work outside the disc and you would be back to the problem the pan was there to solve. Twin-rotor machines need two pans, one per rotor; on Toolsa ride-on power trowels both are supplied as standard.

A pan is attacked in two ways at once: abraded from below by the aggregate and bent from above by the weight of the machine. 3 mm is the compromise between the two — thinner steel ripples under load and transfers its own unevenness to the slab, thicker steel adds weight that somebody has to lift at every change.

The second variable is how the disc is formed. Toolsa pans are pressed, not folded. Pressing shapes the whole face in one operation, so the geometry is identical all the way round and returns after load; folding shapes the rim in sections and leaves stresses that let the steel distort over time.

The material is abrasion-resistant steel. That is what decides how many slabs a pan survives — particularly with a dry-shake hardener, where quartz or corundum aggregate wears tooling several times faster than plain concrete does.

Blades split into two types by the stage they serve. Finish blades are double-sided and work the last passes, once the surface has set — they are responsible for the smoothness and sheen of the wearing layer. Combination blades are single-sided, with a more pronounced leading edge, and go on earlier, between the pan pass and the finish.

Toolsa supplies Finish sets of 4: TA-600/4 for machines with a 600 mm rotor and TA-900/4 for machines with a 900 mm rotor. Four is one rotor's worth — exactly what a walk-behind power trowel carries. A twin-rotor machine runs eight blades, so it takes two sets.

Fit is decided by rotor diameter and mounting hole spacing, not by the make of the machine. Blades for 600 and 900 mm rotors go on any trowel of that size, whoever built it — that is an industry standard, not a feature of one range.

Take the diameter from the machine, not the slab

A pan is not something you size to the floor — it belongs to a specific machine. 610 mm for the TPT-600, 945 mm for the TPT-900 and TPT-900R10, 970 mm for the TPT-836, 1170 mm for the TPT-1046. On another manufacturer's machine the only figure you need is its blade circle.

How to tell tooling is finished

On blades it is the working edge that goes: once it stops being straight, or its thickness has visibly dropped, pressure no longer spreads evenly and the slab shows streaks. On a pan, abrasion is rarely the problem — distortion is. A disc that has stopped being flat prints its own curvature into fresh concrete on every revolution, and no later pass will take that out.

Replace sets, not single pieces

The four blades on a rotor must share the same thickness and the same edge profile. One new blade among three worn ones rides lower than the rest and scores the surface; one worn blade among three new ones stops closing the concrete. That is why sets are sold in fours and replaced complete.

Wash the paste off before it sets

Concrete left to harden on tooling can then only be removed mechanically, which ruins the working face and changes the edge geometry. Pans and blades are washed straight after the pass and stored flat — a pan resting on three points distorts under its own weight and is scrap by the next season, without having finished a single extra slab.

The machines this tooling fits are in walk-behind power trowels and ride-on power trowels. When to get on the slab and how to run consecutive passes is covered by the parent category, power trowels. Edges and the places no machine reaches are finished with concrete hand tools.