Comac Mid-Size Floor Scrubber Guide: Squeegee Sizing and Pad Color Chart Checklist

I'm a quality and compliance manager at a dealership that preps Comac scrubbers for sale and rental. I go through roughly 200 machines and spare-part kits a year, and in Q1 2024 I rejected 9% of first deliveries before they reached a customer. The usual cause wasn't a broken motor. It was a wrong squeegee, a wrong pad, or a machine fitted with both.

And a quick name check: if you searched Comac commercial aircraft corporation of China, you probably landed here by keyword coincidence. That COMAC builds airplanes. The Comac I work with builds floor scrubbers and industrial cleaning equipment. Similar spelling, totally different industries. This article is about the floor scrubber side.

This is the same 6-point quality checklist I run before any mid-size floor scrubber goes out the door. It covers squeegee sizing, blade inspection, and the floor scrubber pad color chart — the three areas where set-up mistakes show up most often.

1. Confirm the machine platform before ordering anything

A mid-size floor scrubber is not a single platform. Disc machines scrub with round pads locked into a rotating pad driver. Cylindrical machines scrub with brush or sleeve rollers that spin like a broom. The two systems use different consumables, so a round-pad color chart is useless if your unit takes cylindrical sleeves.

Before you order parts, write down three things from the machine's data plate:

• Exact model number and current configuration.
• Deck width and pad driver or brush size.
• Whether the machine is disc type or cylinder type.

That takes 30 seconds and prevents a surprising number of wrong deliveries. If you can't identify the platform, photograph the underside of the deck and the data plate, then send both to your supplier.

2. Fit floor scrubber squeegees wider than the cleaning path

The squeegee's one job is to catch the dirty water that the pad or brush just put down. If the squeegee is narrower than the working path, a wet line stays behind on one side, and the operator usually blames the machine instead of measuring it.

The common rule is to use a squeegee roughly 2–4 inches wider than the deck. That gives a margin for turns and slight misalignment, so water doesn't escape around the edge. But treat that as a starting point, not a contract. Check the manufacturer's specification for the exact part — two similar-looking mid-size models can use different brackets, vacuum port positions, and blade cuts.

3. Inspect the squeegee blades before the first run

Most teams check the squeegee frame and skip the two rubber blades inside it. That's backward. The blades do the actual cleaning; the frame only holds them. This is the step I'd recommend you don't skip.

• Remove both blades from the channel and flex the rubber. Look for cracks, nicks, and embedded debris along the wiping edge. A damaged edge leaves a permanent streak pattern.
• Check both blades before installation. Some are shaped differently and carry a top marking for orientation. If a blade is installed backward, water slips under instead of draining into the vacuum.
• Lower the squeegee onto a dry, flat floor and look at the contact line from behind. It should touch evenly across the full width. If one side has a gap, adjust the height or angle before blaming the rubber.
• Most operators replace only the blade they can see from the operating position, but the other blade wears too. If the machine picks up fine going forward but leaves a puddle when reversing, check the rear blade.

A quick water test will tell you the truth: run the machine over a wet area with the vacuum on, stop, and look back. If a continuous film of water remains, the squeegee is lifting, angled wrong, or has a damaged edge.

4. Read the floor scrubber pad color chart from mild to aggressive

A floor scrubber pad color chart is just a shorthand for abrasiveness. The lighter the color, the gentler the pad; the darker the color, the more aggressively it cuts.

The sequence used by most major manufacturers runs like this:

• White — polishing and burnishing. Minimal abrasion, used to create and maintain gloss.
• Red — light cleaning and spray buffing on coated floors.
• Green — routine scrubbing for normal soil on sealed floors.
• Blue — heavy cleaning for built-up dirt, rubber marks, and rough surfaces.
• Brown — scrubbing and light stripping when the floor needs a deeper reset.
• Black — stripping. Designed to remove floor finish completely.

Colors aren't a strict universal law. Two manufacturers can use the same color for slightly different aggressiveness levels, so check the spec sheet, not just the swatch. But the direction is consistent: dark pads strip, light pads polish, and using a black pad for routine daily cleaning is how good floors lose their finish.

I only believed this chart mattered after I ignored it. Early on, I approved a rental machine that had black stripping pads loaded because the previous user wanted something tough. The next customer ran it over a coated VCT floor with plain water. The gloss came off in wide arcs, and the re-coat cost far more than the rental fee. Since then, pad color is on every pre-delivery checklist I write.

5. Match the pad to the floor finish, then run a test patch

Once you understand the color chart, the decision gets simpler: pick the least aggressive pad that will actually remove the soil, and test it on a small area before running the whole floor.

For routine maintenance on a sealed or coated floor, start in the green-to-red range. Move darker only if the floor is heavily soiled or you're intentionally stripping. Bare concrete, quarry tile, and rough industrial floors can usually take blue or brown; polished or freshly coated floors cannot.

Watch out for claims like one pad works on every floor finish. Performance claims need substantiation, and per FTC guidance on advertising and marketing (ftc.gov/business-guidance/advertising-marketing), a manufacturer should be able to back that up. If documentation isn't available, a 60-second test patch on an inconspicuous corner is the only proof that matters.

6. Run a five-minute pre-delivery quality pass

Before a machine goes to work, I run it on plain water with the chosen pad and squeegee. No detergent, no floor claims, just observation. Five minutes catches most of the set-up errors that turn into service calls.

1. Check the pad is centered, the correct diameter for the driver, and wet enough not to grab the floor.
2. Lower the squeegee with the vacuum on and run a straight 30-foot test line.
3. Stop and look back. Drops are acceptable on some surfaces; a continuous film is not.
4. Make one tight turn and one reverse pass. Water escaping on turns points to a squeegee width, pivot, or blade issue.

The test also gives the operator a chance to feel the machine before it meets a real floor.

Three mistakes that show up in my quality log

If you're short on time, read this part. These are the failures I keep seeing in incoming machines, and they're all avoidable.

• Buying pads on color alone and ignoring the floor type. A black pad on a polished or coated floor is a stripping operation, even when the operator intends to do routine cleaning. When in doubt, test in the storage room first.
• Replacing a squeegee with whatever fits the bracket. In my first year, I made this exact mistake: ordered replacement rubber for a mid-size scrubber by matching holes, without checking the blade hardness specification. On rough concrete, the assembly chattered and left a wet snake down every aisle. We went back and replaced it at our cost. Now the blade part number and hardness are on the work order.
• Saving on pad price without checking construction. A customer once saved roughly $35 a case on pads that looked the right color. The pads left swirls across a polished concrete area, and the corrective polishing pass cost more than the entire pad order. Cheaper consumables are only cheaper if they produce the same result.

That's the checklist: confirm the platform, size the squeegee to the deck, inspect the blades, read the pad color chart from mild to aggressive, test on a small area, and do a five-minute water pass before the machine touches a real floor. Six checks cost nothing. A re-coat bill does.