HomeAdviceKnow HowKnowhow

Resin Flooring 4-Tool Surface Preparation Challenge

By Jack Josephsen

I had a chance to do a side-by-side comparison of a floor grinder, shot blaster and two Diamabrush tools. This is what I discovered:

Video Transcription:

So what we've got here today is we're going to run 4 side-by-side tests in the same sized area.

And we're testing different types of resin flooring preparation gear against a control. Something that's mostly known to most people, and that's the grinder.

So I've been fortunate enough to also get a shot blaster which is great because it just feels like we never see enough shot blasting and understand how a shot blaster compares speed wise to other machines or forms of prep.

So today we've got 4 areas. You can see them behind me, but they're each 10 square metres. So we will be recording the time of each, and then we'll do a bit of an analysis of the prep after we're done, and then have a chat about what I saw.

And I look forward to getting your comments and feedback on it so that we can really bring out the most out of this trial. So let's see how it all goes.

Video Transcription:

So it's got some steel shot so that acts as your wear layer so you've got magnetic seals here. That acts as a stoppage to stop your shot getting thrown out. So if you don't prime, you end up with firing shot out the side?  If you don't prime the first two minutes that you fire up with. You're shot.

How did you select what shot you were going to use here?

What we've got is we've got 330, which is our most common size shot that we use. Now, depending on what you're trying to do, it's probably a little bit aggressive for what we're trying to do, possibly. But it will prep that floor perfectly for you. Something that dig holes in it.

And when you say it's probably a bit aggressive, is that because of the size of it?

The size of the shot. Yeah. So if you're doing a thin rollcoat down on the floor, you'd say probably go on the size, you can go down to an S230.

So the finer the shot, the quicker you're going to blast, the finer you're going to leave the surface, but the less material you actually going to take off.

 So if you've got a thicker coating, say a 200 micron epoxy, you might need a slightly larger shot size to get that if you break through that epoxy.

That's the only time you got steel shot.

And why do they tend to use a larger shot?

Because that's an industry failing. One of the industry failings in shot blasting. They think bigger is faster. If you've got S460 I believe, is around 55,000 little balls per pound of shot.

S330 is, I think, is a 155,000. So you got three times the number of balls per kilogram of material going through. You can do it faster, because you get more impacts per millimeter.

But you're getting a finer profile as well. Which you don't need a massive profile.

That's one of the points that I make is based on what we're doing here, what prep is going to be acceptable. I always like shot blasting, but what's required for the application versus the specification and making sure it's the right prep.

Based on what I'm doing here, I'm going to have to scratch coat first to close off and make it all even. But it'll just be rollcoats.

How did the shot blaster go on the slab?

What would you perhaps do differently? What did you notice about this compared to some of the ground surfaces?

One thing probably I would've done differently was perhaps inquire more about what you were actually going to be doing. E.g. what coating you're putting down, how thick the coating was you were having to put down.

What we did notice was that we were, I believe, a little bit quicker than diamond grinding in the situation. And the prep was quite substantially different between the different surfaces you've got here.

I probably would go a lighter shot. So a smaller shot size. We've got S330 in this today.

I probably would've gone just slightly smaller just to give a more even blast and take the material off.

Now if you went slightly smaller, you'd have to travel quicker?

Yes. So we're getting more impacts per millimeter across.

And if you went smaller, how would that change what we are seeing as example on this crack, how that's blown out and cleaned it out?

It would still clean it out somewhat, the real soft material on the top. From the actual other surface, you'd probably get a little bit more of this original surface contamination off, without as much penetration without as much penetration into the concrete below.

It seems to have gone very well, I think, on the overall finish. The actual de-dusting of the surface, if you do that on shot blasting, this is what you see.

If we do that on grinding, that's what we see there, the ground surface is actually vacuumed.  And this hasn't been vacuumed.  

Shot blaster and contaminated areas

The other difference was where we had some contaminated area, the shot blaster had cleaned it up nicely.

The other forms of prep didn't remove the contaminated area. That certainly is another very good pro for shot blasting, is contaminant removal which is great in environments such as food factories, workshops and abattoirs etc.

Well, I'm impressed. I'm always impressed by shot blasting. It's a great profile for resin flooring and for prepping the slab.

We are sitting here, we have chosen to do a rollcoat in this particular application. I can see that I'll probably scratch coat to tidy things up and make it all even. But I'm happy with the profile from the shot blaster.

And I can see the advantages of shot blasting, how it's dealt with the undulations compared to grinding, which has still got some hollows that will need to be touched up in.

What are the limitations of shot blasting?

You're not going to flatten the floor off which in the situation we're not concerned about anyway. And also you are going to open up cracks or anything like that. So if you are doing just a rollcoat down, there will be some patching required in that situation.

Video Transcription:

Tool 1 - Diamabrush Concrete Prep Tool

So the first section that we're talking about here is the section of concrete that we cut with this Diamabrush Concrete Prep Tool.

And when you look at it, you'll see that it certainly cleaned the surface. It put an even cut across the floor. I spent about 15 minutes doing this. You could certainly spend more time making it consistent all the way through but you'd be there for quite a while. This is a 45 MPa industrial slab and I think you'd be there a fair while.

There isn't really any noticeable wear. I don't know if the process would've been faster using water, but as a means of comparison, we are doing it all dry and we'll do them side by side.

So as a prep tool on 45 MPa concrete, I think it's going to be pretty slow going.

Tool 2 - Diamabrush Concrete Prep Plus

So the next tool was using a diamond brush again. This is called the Concrete Prep Plus. You can see there's a lot more blades on it. And that was really noticeable in how much faster it was to cut - to do a pass.

The result is better than the Diamabrush Concrete Prep Tool.

It was faster. It looks like it's better prepared. But overall, I think it's still having a hard time on a 45 MPa industrial slab.

If you were stuck and you had no other choice but to use a tool, I think you probably could prep the floor with it. It would just take you a fair while.

Tool 3 - Floorex 380 Satellite Mk II Grinder

It is a 30-grit, six-segment, soft bond tool. The actual cut is pretty good. It removed a fair bit of the top surface. It was obviously easier. But I did also take longer on this section. I think I was around 16 minutes or 17 minutes here compared to under 10 minutes and then 15 minutes.

So I just went at the natural sort of pace that it felt like it was cutting through and cleaning up well.

As far as preparation for a rollcoat in a non-impact environment, I think this tool can certainly do it. I'd probably just have to be a bit more thorough and make sure that my hollows are well prepared, and that may be hand grinding or may just be doing multiple passes.

Tool 4 - Shot Blaster

So the last of the tools for the slab preparation is shot blasting. And I haven't had a lot to do with shot blasting, but I knew I wanted to see it against the control so that I could get an understanding of what the differences were.

So we did a 10 square meter section in about 10 minutes or 11 minutes. And the overall result, I'm impressed with shot blasting.

What did we learn from shot blasting? 

The size of the shot makes quite a difference to the profile that you leave.

What became really obvious with the shot blasting was it certainly doesn't flatten the floor. It profiles the floor no matter what the undulations are. And that was something that was quite contrasting with the grinder.

The grinder was very rigid, so it prepped the tops very well and really didn't touch the valleys.

So there's a big contrast between the two.

Whereas the Diamabrush tools, they were more even in the undulations. So they obviously coped with the undulations but the concrete prep tool had the lightest prep across all of the finishes.

The Diamabrush prep plus was better again and faster, but still not as intense as the grinder or the shot blaster.


One of the other noticeable differences here was the grinder. Even after I vacuumed it, it leaves quite a lot of dust. The shot blasting is unvacuumed and the contrast is significant.

So we end up with the surface and If we ran a magnetic broom over it, we'd have a coated a surface ready for coating. And that's one of those advantages that became really clear.


One of the other advantages I saw was there was a fair bit of contamination in this area, black residual materials. And even though we've left a patch here, it's actually removed the majority in other areas.

I welcome any questions because this is really important. If we are going to make resin flooring  mainstream, we have to understand what the right preparation is. And the right preparation is not always shot blasting or grinding or Diamabrush.

The right preparation is understanding which is the best tool based on the slab that we have, the specified flooring system, and the budget of the whole thing. So we need to take all of those things into account. And I really enjoy doing this side-by-side test.

As always, take care and keep smiling.

Video Transcription:

Diamabrush Concrete Prep Tool (on a floor sander)

When I look at the finish, I can see that really there are the high spots that I've cut, and you can see that they're light grey, the rest of it is cleaner than beside it, as you can clearly see, but it's cut through the whole top layer.

That's why it's not that light grey colour. The actual colour is quite uniform across the floor, which means that the Diamabrush tool did flex and bend with the undulations in the floor to provide a pretty even finish.

It wasn't the fastest tool. If you're going to prep the whole floor with this tool, you'd be there for quite a while. That might be okay, but that's worth putting into the mix.

Diamabrush Prep Plus Tool

If I walk across to this particular section of slab, this was the Prep Plus Tool. It was notably quicker than the concrete prep tool. You can see, interestingly enough, it also got quite an even grey, meaning that you can see that it cut the hollows as well. It prepped more of the top, so you can see the lighter grey is more prevalent on this side than it is on this side.

I think you could probably prep the whole slab for a rollcoat with this type of tool. Speed would be okay, but still a fair bit of work.


If I come across to the grinder, which is what I keep calling my control, which is what people are quite familiar with. The grinder shows you that it obviously cuts the tops and doesn't cut the hollows. That can be seen because there's dark sections and light sections, the dark sections is where it hasn't touched it. If I actually was to zoom in, you'd see that the tooling hasn't actually touched those hollows.

If I want to keep prepping it to cut it all down, I've got a fair bit of work to do to get it all. Even compare it to this side here, it hasn't cut the tops as much, but overall the prep is more consistent across the ups and the downs.

The grinder was also slower, or I ran it slower perhaps than the Prep Plus tool. But whether that's just because of operator use or not, I don't really know.

Shot Blaster

The shot blaster clearly will prep the hollows as well as it does, the tracks that we are seeing I think is a little bit relating to shooting more shot on one side than the other. The overlapping inconsistencies is more to do with trying to run the small machine by hand.

The operator has to dictate the speed and has to drive it in a straight line, and if they don't then you can see the sort of rows. The other thing that we did change operator at this sort of section here, you can see the difference between the light and the dark.

That first run that was done, was done a lot slower, that's why it's lighter, it's done more preparation.

One of the major differences that I notice is that shot blasting really hammers the surface to reveal anything that's weak. The efficiency of the vacuum process means that it lifts all the contaminants very quickly.

So firstly, you can see that there was something that sat just below the surface, and it's blown the top of it, and whatever was weak on top of it, whereas the grinder hasn't exposed that anywhere else.

The other thing is the actual cracks. The cracks have all been blown out and the edges, I guess, caved in a little bit, cleaned up the sides. It's shown how frail the edges were, whereas on the other forms of prep, it hasn't really hit the edges.

We would have to chase out those cracks, whereas I get the feeling that if I could actually go on and repair these cracks straight as they are.


Overall, that was the idea was to show different methods of prep side by side on the same slab with the same area, and that would give us some context as to how fast or slow different forms of prep are, what the different results are, and what might be suitable for the next flooring project that we are doing.

Of course, this all ties into the concept of if we're going to make resin flooring mainstream, we have to understand what the right preparation is.

When I say right preparation, it doesn't mean that it's always shot blasting. It means that you're evaluating what the specification is, you're evaluating what the manufacturer requires for their flooring system, and then you're coming to site, and you're understanding what are you actually dealing with?

What is the hardness of this slab or the compression strength of this slab, and do you have to make adjustments based on that? That's what right preparation is.

That's the end of this particular trial, I've enjoyed this little side by side test, and I hope you have too. Any questions, of course, just ask. As always, take care and keep smiling.

How you can take action...

  • Products - Take a look at the Diamabrush tools and other specialist resin flooring tools to see how they can solve some real problems for resin flooring installers:
    - Resin Flooring Tools

Click for Technical Support Click for Technical Support

Want to know more about resin flooring?

Get our 20-page resin flooring guide for specifiers and floor owners here

Free Download Free Download