Should I use a drum or orbital sander?

 

This is a very common question people have when trying to decide how much firepower to bring to bear on their floors. The question actually demonstrates a lack of understanding of the process, which we will get into a bit.

Sanding hardwood floors with an orbital or finishing sander can take significantly longer than using a belt or drum sander. It is only recommended to use these tools on floors that are in relatively good condition with only superficial damage to the surface.

What is an orbital sander?

An orbital sander is a small handheld device sander that oscillates. This means that rather than the whole disk spinning on its center axis, it oscillates in the pattern illustrated below. This makes it a lot easier to control as a spinning disk can kick out in every direction. An orbital sander will create a scratch pattern of little swirls.

What are the benefits of an orbital sander?

Orbital sanders are much easier to control. They can sand both the field or ‘body’ of the floor and the edges, which a drum sander cannot. Once you work up to the finer grits, orbital sanders produce a much smoother, less scratchy surface.

They are cheap. You can store them easily or put them up for sale on second-hand sites. I think every household needs one, they cover an array of different jobs.

What are the drawbacks of an orbital sander?

Absolute #1 drawback: power. The difference in power between a drum sander and a random orbital sander is astronomical. For one thing, most random orbitals are around 250 watts, whereas standard single-phase floor sanders can get up to 3900 whats. So we are talking about an order-of-magnitude difference in power.

However, this really doesn’t grasp the sheer difference between these two tools. An orbital sanding motion is much less aggressive even than a spinning motion. My random orbital sander, the Festool Rotex RO150 has both a random orbital and a geared random orbital setting.

With the random orbital setting, I could put that on my hand and it wouldn’t do any damage, whereas if I put the spinning orbital motion on and put that to my hand, well, I don’t want to be graphic.

What is a drum sander?

A drum sander (or big machine as they are affectionately called within the industry) is a large machine that you operate from a standing position. It usually weighs in excess of 50kg and has a large spinning drum that holds the sandpaper.

The drum is applied to the floor, by dropping a lever that lowers the drum onto the floor. Some very rudimentary sanders (such as those often for hire) apply the drum but ‘rocking’ the machine forward until the drum is on the floor.

Just to explain a little better. The drum is always in contact with the floor, but in order to change the belt or turn the machine on, you have to rock it back or ‘lean it down’.

As you can probably tell, English was my weak suit at school.

What are the benefits of using a drum sander?

A drum sander can remove 1mm of wood from the surface of the floor over 200sf in approximately 30 mins. This can vary due to different types of woods and different finishes on the surface as well as types of abrasive. An orbital sander might achieve this in a day. You can learn more about how long it takes to sand a floor here.

So a huge amount of time is saved here. Aside from the time savings, it’s also a ton easier.

Now don’t get me wrong, floor sanders are fairly hard work, they are pulling away from you all the time and you are walking up and down the room many times.

However, the comparative ease with which you can get the job done with a drum sander compared to a random orbital sander is night and day.

Luckily I have never tried sanding 200ft² with an orbital sander but I can imagine my arms dropping off by the end of the day. Also, the constant vibrations through the orbital sander might end up giving you vibration white finger (be sure to take regular breaks if you do decide to do this)

I have to admit I am struggling to come up with other benefits other than faster and easier. Faster and easier is what matters though, right? Ok, let’s talk about some drawbacks.

What are the drawbacks of using a drum sander?

 

Drum sanders are very bulky. Even the smaller ones (the ones that rock back and forth lol) are about 45kg. They can come apart which makes lifting a lot easier, but its still a bit of an effort to get it upstairs to sand bedroom floors and such.

You have to rent them. People don’t like to pay rent for anything, they see it as lost money. If you buy an orbital sander, at least you get to keep the orbital sander (or sell it for at least half your money back on Facebook or eBay). What I would say to those that think like this, is you are buying time and hopefully buying a not-so-sore body.

You can’t (or shouldn’t) finish sanding the floor with a drum sander. This means the last pass of sanding before you vacuum and start putting stain or lacquer down. A long time ago when I was taught the wrong way to sand floors, we finished floors with the drum sander.

Just sand the floor with 120, do the last pass with the edger, then start lacquering or even staining. I am very embarrassed to say this. We never could figure out why it always looked terrible.

This is probably how most DIY’ers will sand their floors, especially those who haven’t found this website. The linear scratch pattern will be visible in the finish. Whereas random orbitals are great for doing fine smooth sanding.

The main reason people don’t want to use drum sanders

SCARY! Hahaha. People often are a little scared to use a drum sander. Which is understandable. I can remember when I first started floor sanding and how I was a little scared. There were many reasons I was scared. For one thing, I was worried I might sand through the floor by accident.

That’s virtually impossible. By some trick of physics, if you hold a drum sander in the same spot for a few seconds, it will create a big dent but it loses its effectiveness, in removing material, very quickly.

I was worried that going over nails and sending sparks into a bag full of wood dust would set the sanding machine on fire and burn the house down with me in it! Again, and it still baffles me, it just doesn’t happen. I have sanded floors with millions of staples and constant sparks flying, but nothing.

Fires do occasionally happen but for some reason, this just isn’t a cause (or I should say an exceptionally rare cause because I can conceive of it happening, I have just never heard of it happening). Suffice it to say, the fear is usually unjustified (as with most things in life).

Summary

As you can see, you use an orbital sander for a completely different reason than a drum sander. Drum sanders are the starting point of any job. You use it to strip off all the old finish and the surface of the wood in as fast a time as possible. This removes all the old dents and stains and gets the wood flat and clean. Everything after that is for smoothing.

So usually you would then edge the floor, drum sand the floor on a finder grit, then again, then edge the floor again then final drum sanding, and only then would you pull out the orbital sander. Even then, it’s not to do the whole floor, but to do the edges where the finishing sanders can’t get. This is the protocol for professionals, but hopefully provides insight into you should use these machines. Only as a fine finishing tool.

If you have decided that renting a drum sander is not for you then I highly recommend you check out my post ‘Sanding Hardwood Floors by Hand.’ It breaks down which hand sanding tools are best for the job. I am happy to answer any questions posted in the comments below.