Review of the Festool Rotex 90, RO 90 DX sander

Brice Burrell

Member
Joined
Mar 13, 2007
Messages
7,385
Well, this is a work in progress.  You can check for updates as they happen on my website, RO 90 review.
Text and photos by Brice Burrell, copyright 2011

Review of the Festool Rotex 90, RO 90 DX sander

Festool's newest Rotex sander, the RO 90. This is the baby brother to the Rotex 150 and 125 sanders, but don't let its small size fool you. This new sander is full of big features and it has a new trick up its sleeve that the bigger brothers can't match.

The Festool RO 90 Sander: One...Two...Three...Four...

One unique sander, two different shaped sanding pads, three modes with the functionality of four tools in one. Only Festool could fit so much into such a small tool. This makes the RO 90 truly a one of a kind sander... It has both a 3 1/2" (90mm) round pad and a delta (triangle) shaped detail pad. Switching between the pads is fast and easy, no tools required. Three modes: rotatory, random orbit and delta.

First there is the aggressive gear-driven rotatory mode. This is an eccentric rotatory action that gives you the benefits of aggressive material removal with a less pronounced circular scratch pattern. This a dual function mode for course sanding and polishing. Second, a random orbit mode, this function turns the Rotex 90 into a finish sander. Third is the delta mode. It's an orbital action used with the delta pad for detail sanding or getting into corners giving the RO 90 its fourth function. With all these functions the RO 90 can take on a surprising number of tasks. I don't know of a more versatile sander on the market today.

PIC_2890sm.jpg


Here's what is included when you buy this sander:
Rotex 90 Sander
One Soft Round Sanding Pad
One Delta Sanding Pad
Edge Protector
Plug-It Cord
Selection of Sanding Abrasives
Owners Manual
T-Loc Systainer

The Festool RO 90 Sander: A New Rotex, with a Twist

So this is it, the new (mini) Rotex, with a very cool twist. That twist is in the wrist-you can change sanding pads with just a quick twist. If you’re familiar with Festool’s two other Rotex sanders you know they offer both a rotary and a random orbit (ro) mode. The RO 90 takes it a step farther with the introduction of a third mode, the delta mode. There’s a mode selection switch on the top of the sander. Switching between the rotary and ro modes is straight forward, just turn the switch. For delta mode you need to depress the switch and turn it. This not only sets the sander in the orbital delta mode it also locks the spindle so you can change the sanding pads. The round pad twists off with about a 1/8 counterclockwise turn. Putting the pad back on is just the opposite, 1/8 turn clockwise. Installing the delta pad is the same process, the only thing different is to remove it you’ll need to press the green button to unlock the pad and twist it off.

RO90sm.jpg


Here’s some more info on the sander and its modes. The RO 90 has a 400 watt motor (about 3.3 amps), softstart, stepless variable speed control, constant speed under load and thermal and overload protection. Also, a sealed metal housing for the gears, Plug-It cord and dust port (accepts D27 hose).

As noted earlier, the rotary mode isn’t a pure rotary action. Another reviewer compared it to a Spirograph, I suppose that’s as good of a description as any. This mode is powerful and with a coarse abrasive it can aggressively remove material. Festool also offers a backing pad, felt, sheepskin and a series of sponges for polishing. (Polishing isn’t one of my areas of expertise so I won’t be covering this facet of the RO 90 in this review.)

The random orbit mode has a 3 mm stroke so the RO 90 is more of a finish sander in this mode. The small pad makes it easy to get into tight spaces, sand narrow pieces or edges. The sanding pads have a built-in sanding pad brake (rubber lip at the top of the pad). This helps keep the pad's speed under control before coming in contact with the work piece. It also helps the sander "run down" faster so you aren't waiting to set the sander down between uses. Most sanders have that have this feature have it mounted on the sander itself. The brake is a consumable item that needs replaces over time, it's nice to have them in the RO90's pad so when you replace the pad you also get a new pad brake.

The delta mode is what sets the RO 90 apart form the other Rotex sanders. It's a purely orbital action as apposed to the arcing action that "multi-tools" have. The RO 90's orbital sanding action not only sands more effectively it doesn't leave a pronounced scratch pattern like the multi-tools do. One other thing of note about the delta mode. That is, it has a safety mechanism to prevent the mode from being changed with the delta pad in place. You physically can't turn the mode switch to the ro or rotary positions with the delta pad on the sander.

I think the abrasive Systainer is a nice accessory for the RO 90. It holds maybe 300-400 sheets and each slot can hold both round and delta abrasives. Below is a short video showing the abrasive Systainer.

Festool RO90 Abrasive Systainer

The Festool RO 90 Sander: In Use

I’m a residential remodeling contractor so the type of work I do each day can vary considerably. A versatile sander like the RO 90 is idea since it can handle all sorts of tasks from exterior paint stripping to producing a fine finish on furniture. At 3.3 lbs. it’s light enough to use on vertical and overhead surfaces that I might encounter stripping paint on siding or soffits. It somehow feels lighter in your hands than three pounds. One thing I noticed right away was the rather odd balance of the sander on horizontal surfaces. The weight of the cord and vac hose makes holding the sander with one hand a challenge. Festool recommends a two handed grip, one on top of the head of the sander and the other hand at rear holding the tool Plug-It cord/hose. This made an enormous difference in how the sander behaved and made the RO 90 easy to control. I'd put that control to the test with the RO 90 in rotary mode in short order. The first several tasks for the RO 90 were dirty and unpleasant work but it didn’t even seem to break a sweat tackling these jobs.

In Use: The Rough Stuff

I do some painting as part of my work. Exterior prep and painting are not exactly glamorous work. My arsenal of Festool sanders has made the prep a little easier. I envision the RO 90 adding another layer of versatility to the arsenal. With the season turning to spring I jumped on prepping a couple of old window sashes at my house. I have a 90 year old Craftsman style house. These sashes have been neglected and they need some serious prep work to bring them back. With both sashes remove I started in on the lower sash. Its paint was peeling and really wasn’t adhering all that well anymore. I went to work on it with the RO 90 in rotary mode with 40 grit Granat. The RO 90 tore through the five layers of paint without trouble. I bet I spent less than ten minutes stripping all the paint from the exterior side of the sash. I then switch over to the delta pad and sanded the glazing. A few more minutes and the paint was sanded off the glazing.

The paint on the upper sash was in a little better shape since it was partially protected by the overhand of the roof. I decided to get out the video camera and shoot the sanding of the upper sash. As you can see in the video below this isn’t a new sash with one coat of paint just to make the RO 90 look good. This is the real thing, a no BS look at how this tool handles this tough job. The video is edited to just under five minutes, the whole sash took about twice as long. Don’t take my word that the RO 90 did a great job, take a close look for yourself at the dust collection, control of the sander and its effectiveness.

Sanding an old Window sash with the Festool RO90.

I know watching me sand a window sash for five minutes isn’t most people’s idea of a good time. You may have missed some exciting stuff if you skipped through the video (well exciting to me anyway). First, thing to take note of in the video is the aggressiveness of the RO 90. It was in rotary mode with a hard sanding pad, 40 grit Granat. Even with the RO 90 in rotary mode it was easy enough to handle to carefully sand the muntins. I think it’s also important to talk about the dust collection. I’d say the dust collection was only passable. It’s only fair to point out that this was aggressive sanding on narrow pieces where dust collection is more difficult and not typical of my overall experience with the RO 90. The dust collection was able to help keep the abrasive relatively clean. Aggressively sanding can be hard on abrasives. The paint can heat up from the friction-it will start to melt at some point and stick to the abrasive (also known as loading). Between the dust collection and the stearated coating on the abrasive loading was minimal.

Having one tool with a round or delta pad was handy while working on a set of sawhorses. However, imagine doing this job where it normally takes place, off the ground and on a ladder. The sanding pads are small enough to stick in your pocket along with a handful of abrasives. Now you’ve got everything needed up on the ladder with you. This is where the RO 90 is really going to be useful for me.

The next tough job was sanding old varnish off stair treads. The stairs seemed to only have one or two coats of some sort of varnish. Varnish tends to melt when you try to sand it. This would test the Granat abrasive’s ability to resist loading. There will be a carpet runner going down the middle of stairs so only the edges would need sanded and refinished. The treads were in fair condition overall so the sanding went relatively quickly. I shot a short video, check it out below.

The Festool RO 90 Sanding Stair Treads

It turned out the Granat handled the varnish with no problems at all. In fact the round discs didn’t have much loading at all after 10 treads. The RO 90 with the round pad was able to sand right up to edge of the stringer and riser with the edge guard in place. Then the delta finished off the corner and anything remaining along the edges. The delta abrasive did load on one of the tips as you seen in the video. Keep in mind I worked the tip of the abrasives pretty hard in the corners and that ended up melting the varnish. The RO 90 virtually eliminated the need for any hand scrapping. You can also see in the video that the RO 90 really bit into the soft pine treads so I needed to hang on to it in rotary mode. After the finish was removed I’d switch into ro mode to clean up any swirl marks left behind and work through the grits to get the finish I wanted. The dust collection was much better on the treads than the sashes. I think was because of larger surface and less loose material was removed.

With this type of hard use the delta abrasives and backing pads wear out more quickly than what you may be used to with other Festool sanders. Remember, when sanding a corner or other small surface the RO 90 is putting 400 watts on a small surface of the sanding pad and that will heat up quickly. This heat can, or more realistically, will cause the hook and loop on the backing pad to melt at some point. These backing pads are meant to be consumable (used and replaced). They are reasonably priced and very easy to change out. The good news is they can be rotated just the abrasives to have a fresh tip to work with. If you anticipate using the RO 90’s delta pad for aggressive sanding you may want to pick up an extra set of backing pads so you won’t be stuck if/when the hook and loop gives out.  

In Use: Fine Finishing

I’ll be honest, I was skeptical about finish sanding with the small pad of the RO 90. Of course you wouldn’t want to try to sand large panels. However, for smaller pieces like face frames, rails and stiles and the like, the RO 90 turned out to be nicely suited for these sanding jobs. I think where most people might be pleasantly surprised with the RO 90 would be as a detail sander. The delta pad isn’t just sanding into corners-it will get into all sorts of narrow edges, small nooks and other odd spaces where no other sander will fit. Once you get used to the idea of having a good detail sander you’ll find more and more uses for it.

I tend to buy S2S or S4S stock from the lumber yard, some of it is nicely milled and some of may have a ton of planer marks. With the RO 90 I can quickly switch into the rotary more when I run into planer marks and then back to ro mode to keep on finish sanding. Same thing if I don’t quite get faces of my pocket screw joints perfectly flush.  

RO90%20detailsm.jpg


In the past I’ve used my multi-tool as a detail sander. I would describe its use in that function as better than nothing, but just barely. The RO 90 on the other hand works very well as a detail sander. The delta pad has slightly convex sides that allow you to get right up to an edge without “chattering” along the adjoining surface. The only downside to sanding small edges or small surfaces of any kind is the dust collection is not the best in delta mode. You aren’t going to have a dust cloud in your face but be prepared for there to be some dust left behind.

PIC_2964sm.jpg


I like to use the delta pad to sand edges too. The orbital sanding action helps me keep the sander flat then the edges on work piece stay nice and square.

RO90%20exteneda.jpg


In the pictures above you can see the extended delta pad. This pad extends the reach of the delta pad and it can be used with or without a foam backing pad (the extended delta pad works best without the foam backing pad being attached). With the abrasive attached directly to extended pad (no foam backing pad) it can reach in very narrow spaces like between the slats of this louvered shutter*. Another use would be to extend the RO 90’s reach when the height of the sander doesn’t allow it into a space like that of a cabinet toe kick. It's worth noting the dust collection with the extended pad isn't very good, so be forewarned.

There are a couple of options for buying the extended pad. The first is buying whole pad (part # 496803). The advantage of this option is being able to quickly switch to the extended pad. The second option is to buy the set of extended backing pads only (part # 497483). This set is meant as to be used as replacement parts. You only need to take out three screws from the regular pad to change to the extended pad. It takes a little longer to switch between the pads this way. I decided since I won’t need the extended pad all that often it would be better to save a few bucks and deal with the slight inconvenience of pulling the screws to change out pads. In the lower of the two pictures above you can see (from left to right) the regular delta pad taken apart, the extended backing pad and the foam backing pad.

My experience with the Granat abrasives was very positive for sanding finishes. However, I would not recommend it for finish sanding bare wood. The finer grits work okay but the coarser grits leave deep scratches that are harder to sand out. The reason for the deep scratching is the grit particles on Granat are open, or spaced farther apart than some of the other Festool abrasives. That’s great for aggressive sanding and to resist load, not the best for bare wood. I think for most woodworkers would be happier with Rubin or Brilliant 2 but don’t take my word for it, try it out for yourself.    

The Festool RO 90 sander: She’s a Beauty, Warts and All

Just as the title says this tool is a beauty. It’s small, versatile and easy to handle. For me it makes sanding a less tiresome job. However, there are some points to consider if you’re thinking about picking up one of these sanders.

4in1crop.jpg


The first question that comes to mind, does the RO 90 really have the functionality of 4 tools in 1? The answer, yes, albeit in miniature form. On one hand the small size of the RO 90 is one of its assets, on the other hand, it’s a limitation. Sure, the RO 90 wasn’t designed for working on large table tops, nor would you want to try to polish an entire fleet of cars with it. It is ideally suited for face frames, rails, stiles and as a detail sander. Sanding overhead surfaces, working on ladders or scaffolding are areas where the RO 90’s small size and versatility shines.

So what if you already have one or all of the other tools that share the RO 90’s functions? This was the question that I had to carefully since I have most of these other tools already. I worried that all the overlapping functionality of these tools might not make the RO 90 a good investment for me. I was fully prepared to take advantage of Festool’s 30 day, no questions asked, return policy if the RO 90 didn’t provide real value for me.

There is overlap for sure but I decided there was a place in my arsenal of sanders for the RO 90. I did end up making some room for it by selling off my second ETS 125 and Deltex. As a professional woodworker/remodeler, having more tools and overlap isn’t such a bad thing since there are often other workers using my tools on the jobsite too. For those looking to maximize functionality with fewer tools I would recommend a 6” (150mm) random orbit sander alongside the RO 90. With that combination you can tackle large panels, narrow stock, aggressive and detail sanding as well as polishing.

More to come.....

* See comments in posts # 28 and 29 about finish sanding this shutter.
 
Thanks Brice as always you are quite informative. Im going to order one of those tonight. Im also going to order the sand paper as well.
 
sancho57 said:
Thanks Brice as always you are quite informative. Im going to order one of those tonight. Im also going to order the sand paper as well.

Hey, I'm always glad to help guys spend their money. [big grin]

I've added more to the first post.
 
Brice,

The only problem I see is that people might not like having their window sashes pulled out and sanded for a video while no one is home.  Especially if they're not having work done on their house.  [big grin]  Make sure the cops know you're just the friendly neighborhood contractor.  [wink]
 
[eek]Thanks for the review,I just received mine today and It just blows me away how well it works compared to my old school(Makita,Dewalt and Ridgid) sanders.Im in love.
 
I know I used the heckoutta mines today. That RO 90 is awwesome for sanding rails and stiles. Im making some cab doors and I cant imagine sanding them with my old 5" default or Bosch sander. When I had to take out some burn marks from the router bits I just switched to the agressive mode and it took care of them in a heart beat.

aaannnndd No dust to speak of to clean up.

 
sancho57 said:
I know I used the heckoutta mines today. That RO 90 is awwesome for sanding rails and stiles. Im making some cab doors and I cant imagine sanding them with my old 5" default or Bosch sander. When I had to take out some burn marks from the router bits I just switched to the agressive mode and it took care of them in a heart beat.

aaannnndd No dust to speak of to clean up.

Oh, this looks like my justification to buy it as I'm finishing up some cab doors now.  Well, I did just buy a Domino and it's tough trying to avoid any more slippery slopes!!!!
 
Well, that wraps it up after seeing Brice sand his sashes and I'll be buying the RO 90 very soon.  I know that Uncle Bob is still waiting for me to spring for one and I'll do this when he offers the Sandpaper assortment as well.

BTW my home is a Prairie style built over 86 years ago and I really need to prep and paint its exterior wood trim.
 
Brice,
very nice review.
Can you tell me what sanding paper and grain did you use for the stair treads?

Nico
 
I would have so used my 150 on that window and stairs, and clean up with the Deltex, would be finished way quicker.
 
It is painful watching you guys sand stairs with these rotexes.
Knowing that you could sand the whole set of stairs in that time with a floor edger  [blink]
 
nehardwoodfloors said:
It is painful watching you guys sand stairs with these rotexes.
Knowing that you could sand the whole set of stairs in that time with a floor edger  [blink]

Sure, when you own an edger. [blink] BTW, it's painful for me to watch flooring guys do carpentry. [tongue] [big grin]
 
Just curious, what is the significance a "floor edger"?

I just did a quick search and it looks like it's basically just a sander with a different type of handle?

Some of the ones I'm seeing seem to use smaller disks than the RO 150...

If that's all that's going on, why not just a special handle attachment of some sort to let the RO 150 be used as one?
 
Alex said:
I would have so used my 150 on that window and stairs, and clean up with the Deltex, would be finished way quicker.

Alex, no argument about the 150 covering more ground. There are a couple of point to consider.  First, this is a review for the RO90, so I'm showing what the RO90 can do in these applications.  Even if there are other tools that might be more effective doesn't mean people don't want to know if this tool is up to a job like this.  Beside, there are plenty of people that don't necessarily have other tools at their disposal that might do the job faster.  Also, you'd spend $525 USD on a RO150 and $290 USD on the DX93, that's $815 USD.  Or, spend $375 USD on the RO90 to do the same job, albeit a little slower.  Furthermore, there are times when have one smaller tool is preferable to have two tools, for example:
Having one tool with a round or delta pad was handy while working on a set of sawhorses. However, imagine doing this job (sanding window sashes) where it normally takes place, off the ground and on a ladder. The sanding pads are small enough to stick in your pocket along with a handful of abrasives. Now you’ve got everything needed up on the ladder with you. This is where the RO 90 is really going to be useful for me.

I intend to talk about where the RO90 falls into line with the rest of Festool's other sander in regards to function, speed/effectiveness and overlapping capabilities later in this review.     
 
fdengel said:
Just curious, what is the significance a "floor edger"?

I just did a quick search and it looks like it's basically just a sander with a different type of handle?

Some of the ones I'm seeing seem to use smaller disks than the RO 150...

If that's all that's going on, why not just a special handle attachment of some sort to let the RO 150 be used as one?

Edgers are large (relatively speaking) rotary sanders.  They are a pain to use, a guy can make a real mess with one of these things.  If you take a close look at a floor, there's a fair chance you'll see where the edger has been.  
 
So Brice, after doing that first stair tread, do you think it would have been any easier to use a scraper in the corner and then the delta pad to sand it smooth quickly?

Also, do these homeowners get any royalties for having their work shown on video?  [big grin]
 
Ken Nagrod said:
So Brice, after doing that first stair tread, do you think it would have been any easier to use a scraper in the corner and then the delta pad to sand it smooth quickly?...

Not for me because I have to stop to often to bang my head against the if I were using a scrapper. [tongue]  I'm not much for patience with hand tool but yes, a guy with some experience could probably make quick work of it with a scrapper.  The guy with little or no experience, different story. 
 
Brice Burrell said:
Ken Nagrod said:
So Brice, after doing that first stair tread, do you think it would have been any easier to use a scraper in the corner and then the delta pad to sand it smooth quickly?...

Not for me because I have to stop to often to bang my head against the if I were using a scrapper. [tongue]  I'm not much for patience with hand tool but yes, a guy with some experience could probably make quick work of it with a scrapper.  The guy with little or no experience, different story. 

Thanks.

Just a thought, but maybe you could have sanded the treads with the RO90 and then showed the customer how they need all of the treads replaced because getting those corners is too labor intensive and costly. [wink]  --- More work and money for you.  Taking that a step further, we could get a good video out of you while you replace the entire staircase, not JMB style though.  I'm just tryin' to help out your wallet.
 
Back
Top