time studies for the ro 90

[historichouseguy]

Anyone care to share how the ro 90 has performed sanding exterior siding for paint prep?
I have about 4000 SF of siding to prep for painting. Minimal layers  (maybe 3) house was stripped in the 70"s.
Im going with the 90 as I have lots of detail as in smaller flat surfaces. As well as 40 odd windows.
I have to think this will be a huge time saver VS hand scrap and touch sand. Better outcome too.
thanks in advance

 

[ear3]

The RO90 will be a huge time saver vs. working by hand.  If you were to get just one sander for the job, it would probably be the RO90 because of its ability to do corners and detail work.  If you are able to get more, though, you might consider pairing it with one of the larger Rotex sanders, or even the RAS, which has the fastest removal rate of all the Festool sanders, though since it works like a low speed grinder, can easily dish your surface if you're not careful.

In advance of some other folks chiming in with more specific experience of exterior work/paint prep-- if you search ro90 and "exterior" or "strip" or some other keywords, you'll be able to pull up a lot of examples.

Here's one for example:http://festoolownersgroup.com/festo...the-life-without-an-ro90/msg277270/#msg277270

Also a review by the author of the above post [member=13337]Scott Burt[/member]http://topcoatreview.com/2013/01/festool-ro90/

Maybe someone else will remember the thread I'm thinking of, but there was a person who posted a video within the last 6 months showing him using an RO90 to sand the rectangular, sunken channels of wither a fence or a tongue and groove exterior wall.  He did so by cutting up an old pad to make a profile that fit the channel, affixing it to the existing pad of the RO90, and then sanding in delta mode -- similar principle to the LS130.

 

[bobfog]

The RO90 won't even be on the same planet as working by hand. In forced rotation mode, with a low grit paper it will strip siding at a rate of knots.

I have a love hate relationship with my RO90. In forced rotation mode I love it, but I've never rated it as a delta/detail sander; it just doesn't balance properly and is a bit too big to be as finessed as a dedicated delta sander, so you end up destroying a lot more of the triangular pads and wearing out the edges of the papers. So if it were me I'd use a separate delta sander that a) performs better and b) means you won't have to switch over the pads.

A final word of caution, or maybe more of a heads-up. The RO90 runs pretty hot if used for extended periods of time and whilst not painful can be a little uncomfortable if holding for long periods in a warm climate/indoors.

 

[AlexThePalex]

The RO90 is way too small for a 4000 sqf job. That's going to take ages. A RO150 would do better, or a RAS115 if you want to go down to bare wood.

The RO90 is mostly suited for the finer jobs like window or door trim.

I can't find myself in Bob's comment above about the delta sanding, the RO90 does just fine there.

 

[bobfog]

The RO90 is way too small for a 4000 sqf job. That's going to take ages. A RO150 would do better, or a RAS115 if you want to go down to bare wood.

The RO90 is mostly suited for the finer jobs like window or door trim.

I can't find myself in Bob's comment above about the delta sanding, the RO90 does just fine there.

We are talking about siding here though.

So a) the siding is likely to be about 4" so the RO 150 would be a bit pointless, having 2" of the pad hanging off the edge of each strip; also more likely to round over the edges. Also the weight of the RO90 is significantly less than the 150, which will be a great advantage working vertically. It's also likely that over time the siding has become slightly cupped/dished, so the smaller pad of the RO90 will be better for being able to hit awkward areas while keeping the pad flatter and not digging in using the edge of a 6" pad.

b) The OP stated that he only has 3 layers of paint to remove, the inherent risks of such a heavy duty tool as the RAS115 seems a bit overkill.

As for the delta performance, I guess different people have different expectations. For me there are better dedicated delta sanders that do a better job for stripping paint into corners.

 

[peter halle]

I would definitely look at the RAS for this.  You can slow down the RAS and / or go finer grit. 

Love my RAS!

Peter

 

[Shane Holland]

Welcome to the forum.

I would agree with all of the other comments. Going over 4,000sqft only 3½" at a time is going to be a slow process. Consider the RAS or Rotex 125 (which is better suited size-wise for siding than the Rotex 150) in addition to the RO 90. The RO 90 is going to be great for the details and windows, but I think you'll be well served by having another sander for the siding.

 

[bobfog]

I would definitely look at the RAS for this.  You can slow down the RAS and / or go finer grit. 

Love my RAS!

Peter

Those are fair points.

I guess it depends on the size of the reveal, if it's a more standard 4" reveal then I maintain the RO90 would be better, as in my experience it makes for a better job if your pad is slightly small than the width being sanded.

If it's much more than 5" then the RAS 115 could be an option, though at 2.3kg it will feel a lot heavier over extended periods.

 

[jools]

I use the RO90 almost exclusively for house paint prep. For preparing a sound surface for re-painting it's hard to beat. Siding, frames, corners mouldings rails etc all done with ease.For removing old coatings back to bare wood it's slower than a RAS 115, belt sander or metabo LF724 that I own and all have a place to use but with the RO90 your a lot less fatigued. I've used brilliant 2 60 or 80 grit which seems to last the longest and give best results. We use 2 undercoat 1 topcoat systems here and anything smoother than 80 grit is a waste of time. With opaque varnishes I go to 120 grit as the build of film isn't as thick although most stipulate smoother than 120 doesn't provide enough of a key for the coating to adhere properly. Perhaps a USA house painter will chime in with how smooth you need to be for your latex systems etc.
I use my RO90 speed 6, vacuum high for hours on end and have never had it over-heat. It must have at least 800 hrs of use on it.

 

[AlexThePalex]

We are talking about siding here though.

So a) the siding is likely to be about 4" so the RO 150 would be a bit pointless, having 2" of the pad hanging off the edge of each strip; also more likely to round over the edges. Also the weight of the RO90 is significantly less than the 150, which will be a great advantage working vertically. It's also likely that over time the siding has become slightly cupped/dished, so the smaller pad of the RO90 will be better for being able to hit awkward areas while keeping the pad flatter and not digging in using the edge of a 6" pad.

- Makes not difference at all that the RO150's pad is too big. You can easily use it on any size surface you want.
- Rounding over edges doesn't really happen. Unless you want it too, and in fact can be desireable because paint will last longer on a rounded edge than a sharp corner. This is very often done on purpose and is called "breaking the corners". Round over edges is undesired with furniture but not with outdoor painting.
- Weight; I must be superman, because  can work all day with the RO150 in any position I want. I never get the weight complaint.
- Cupping: you can very easily move the sander along with the cupping, but also reduce the cupping a bit. The edge of the RO150 doesn't have to dig in at all, just keep the sander moving. Technique. 

Anyway, have fun doing 4000 sqf with your RO90, I'll do the same job much faster and cheaper and save me some sweat.

b) The OP stated that he only has 3 layers of paint to remove, the inherent risks of such a heavy duty tool as the RAS115 seems a bit overkill.

As was already said, grit and speed selection make the RAS very controllable.

As for the delta performance, I guess different people have different expectations. For me there are better dedicated delta sanders that do a better job for stripping paint into corners.

I have the DX93 and also had the RO90. I also had a Metabo and a Bosch delta sander. The DX93 is by far the best of the 3 dedicated delta sanders I had, and the RO90 practically does the same, I see no real difference. As for your earlier comment about balance, what balance? A delta sander is a small pad on a long stick, there is no balance except for what you provide.

 

[bobfog]

We are talking about siding here though.

So a) the siding is likely to be about 4" so the RO 150 would be a bit pointless, having 2" of the pad hanging off the edge of each strip; also more likely to round over the edges. Also the weight of the RO90 is significantly less than the 150, which will be a great advantage working vertically. It's also likely that over time the siding has become slightly cupped/dished, so the smaller pad of the RO90 will be better for being able to hit awkward areas while keeping the pad flatter and not digging in using the edge of a 6" pad.

- Makes not difference at all that the RO150's pad is too big. You can easily use it on any size surface you want.
- Rounding over edges doesn't really happen. Unless you want it too, and in fact can be desireable because paint will last longer on a rounded edge than a sharp corner. This is very often done on purpose and is called "breaking the corners". Round over edges is undesired with furniture but not with outdoor painting.
- Weight; I must be superman, because  can work all day with the RO150 in any position I want. I never get the weight complaint.
- Cupping: you can very easily move the sander along with the cupping, but also reduce the cupping a bit. The edge of the RO150 doesn't have to dig in at all, just keep the sander moving. Technique. 

Anyway, have fun doing 4000 sqf with your RO90, I'll do the same job much faster and cheaper and save me some sweat.

b) The OP stated that he only has 3 layers of paint to remove, the inherent risks of such a heavy duty tool as the RAS115 seems a bit overkill.

As was already said, grit and speed selection make the RAS very controllable.

As for the delta performance, I guess different people have different expectations. For me there are better dedicated delta sanders that do a better job for stripping paint into corners.

I have the DX93 and also had the RO90. I also had a Metabo and a Bosch delta sander. The DX93 is by far the best of the 3 dedicated delta sanders I had, and the RO90 practically does the same, I see no real difference. As for your earlier comment about balance, what balance? A delta sander is a small pad on a long stick, there is no balance except for what you provide.

Well as they say, there is more than one way to skin a cat, I believe the points I made are valid. The OP can take onboard everything said in this thread and make up their own mind as to what they think is the best option.

 

[Holmz]

If he needs three or four sanders he may be financially better off subcontracting it out

 

[Scott B.]

Just my opinion as a painter, I'd pick the 125. The 90 is small (but great for details, as Shane mentioned). The 150 is too big and heavy. Someone above said "who cares if its too big?" If the siding reveal is 3.5"-4" (which is pretty common in the States), then a 6" pad is not only heavy on vertical siding, but also blowing 20+% of its pad size in dust in your face for hours on end in this type of work.

The 125 is the best choice, and I only say that based on experience:

 

[Shane Holland]

Thanks for stopping by to give some firsthand experience, [member=13337]Scott Burt[/member]. One thing that didn't come up, and I hate to admit I don't know the answer for sure, is whether the edge protector works on the lap on siding. Or is it too high up to prevent contact with the board over the one you're working on?

 

[Scott B.]

Thanks for stopping by to give some firsthand experience, [member=13337]Scott Burt[/member]. One thing that didn't come up, and I hate to admit I don't know the answer for sure, is whether the edge protector works on the lap on siding. Or is it too high up to prevent contact with the board over the one you're working on?

Edge protector doesn't really help on vertical siding sanding. It is more practical at keeping you off things when you are sanding horizontal. Like a floor into a baseboard, where things are more predictable.

By that I mean that beveled claps run a bit tapered by nature, so when sanding the face of a beveled clap, you only lose surface by having the guard on, plus (after a few hours of experience), you want to be able to lay right in upside down to get the fat bottome edge of the claps too.

On the vertical faces of claps, ideally, you are sliding the edge of the abrasive right up under the fat edge of the clap above you when sanding. Conveniently, the abrasive on a Festool is usually a good 1/16" proud of the base pad, so you have a sacrificial edge, on surfaces where swirls don't really happen, and if they did, product would have your back.

 

[Shane Holland]

Solid insight, Scott. Thanks.  [thumbs up]

Sanding siding is something I've never done personally. So, thanks for the education. Always stuff to learn...

 

[BMAC]

Great video of paint pros doing a job right Scott! Well done Sir and thanks for sharing.

I do mostly custom millwork and cabinetry (and some minor drywall repairs) and your video reminds me of a common trade saying around here when you bump up against other trades taking on project not in their wheelhouse and not doing it properly.

As the saying goes "I do all day long what it takes you all day long to do".

 

[Scott B.]

[member=48572]Shane Holland[/member], you are welcome. I agree...important to be learning every day.

[member=40924]BMAC[/member] thanks!

 

[historichouseguy]

All,
Thanks for your time and input. Really great! Yes to 4"TW siding. Yes to lots of details . why I am still leaning toward the 90.
If I need to I will get the larger as well but really I think smaller is better here even if it takes a bit longer on the bigger flats.The most important two things to me are a superb finish and lead dust containment. Supposedly this house was torch stripped in the 70's but I am not convinced its all gone. Especially up high. This does not necessarily need to go down to bare wood just a good smooth prep.
As to experience, been working on antique houses for 40 years and no I have not seen it all and certainly not done it all. Thats why Im askin! I never considered Festool an option at 61 yrs old, figuring they are to "expensive" at my late juncture in my career but the lead dust issue is unequivocally a game changer. I'll be getting it soon and do some testing on my 252 year old siding. Steve