Sander Advice

[Jmacpherson]

Hi all

I'm looking for some sander advice in terms of which avenue or path to go down, ie. 150mm or 125mm route.
I'm considering the Rotex option or even the possibly the Rotex and ETC EC combined.

I've tested/handle the ETC EC 150/5 at my tool supplier and it is very comfortable in the hand and very ergonomic.
I've done the same with the Rotex RO 150. I found the 150 rather heavy and I found the circumference of the body quite large in terms of grip area for my hand. I'm aware that the sander will sit flat and then the weight becomes a non-issue unless using it vertically.

I'm in the process of arranging a demo of the RO 125 and ETS EC 125/3 because of my concerns regarding the size and weight of the RO 150. I have occassional issues with my right wrist, hence ergonomics is key to me.

My tool supplier doesn't carry stock on hand of the 125mm range of products or accessories, they just don't sell enough of it.
150mm is more popular so they always carry stock.

Question, how much smaller is body/frame/grip area of the RO 125 vs RO 150? It is hard to tell from images online but I don't see much difference?

To assist your answers this is what I intend using the sanders on:

Outdoor pressure treated wood and making outdoor furniture. Timber dimensions generally range from 38mm to 114mm. If assembled together might be in the 300-400mm wide.
Stripping off old coatings from outdoor gates and furniture. - Rotex heaven
MDF, never wider than 600mm. The odd gloss white interior shelf unit but I try to avoid MDF due to having to seal the edges. ETS would be perfect here.
Plywood now and then
Looking to start working with some exotic hardwood - think rotex or both would be beneficial?
My own fascia boards to be repainted every few years. - rotex heaven

I know 150 removes 44% more material than 125.
My tool supplier doesn't stock 125 so everything has to be ordered in so I have that in the back of my mind
Sometimes 150 is just too big. Try sanding 20mmx20mm / 1inchx1inch with a 150mm sander, bit of a pain.
I know some people suggest sticking to one size so that you can share abrasives.
Would it be worth considering say a Rotex 125 and a ETS 150 instead? Or vice versa and go with a Rotex 150 and ETS 125 for the smaller

Thanks

 

[Stone Message]

From the uses that you indicate the RO150 sounds ideal. Do not worry about wrist ache - I have quite severe arthritis in fingers wrists and elbows and I do not have any problem with the RO150 although I have never used it for more than a couple of hours non stop and only for short periods working overhead.

Do not underestimate the flexibility and power of the ETS EC 150 (I have the /3 model). With 60 or 80 grit granat you can remove quite a bit of material in a relatively short time. With the finer grits it comes into its own as a finish sander and has been my "go to" sander for quite some time now. It is light, easy to manage and relatively quiet.

The ETS EC 150 takes the same sanding sheets as the RO150 and so if you can mange both then go for it. I really hope that your wrist condition is not worse than mine and assure you that with practice the RO150 is not difficult to handle.

Peter

 

[Holmz]

...

I've tested/handle the ETC EC 150/5 at my tool supplier and it is very comfortable in the hand and very ergonomic.
I've done the same with the Rotex RO 150. I found the 150 rather heavy and I found the circumference of the body quite large in terms of grip area for my hand.
...

A ETS/EC 150 is a good choice and the stroke is 5-mm so it hares along.
Plus as you know it is easy to use.

A RAS is another powerhouse for removing material and outdoors on Fashcia do you need dust collection? Bosch and Rupes also make a similar beast.

I would suggest that you Worry about the future when it gets closer... As one can also spend a lot for some hand planes, which for hardwood can be better than a sander if you want smooth and FLAT. Or a 1/2 sheet sander. Or a corner sander. Or scrapers.

The ETS/EC is a nice sander, and also light enough to use vertically. Mirka screens work on it too.

 

[ajshobby]

i just went through this myself.  I found that due to my workflow about 80% of my sanding is on items that are 5" or narrower.  I ended up purchasing the ets 125 ec and bought the 150mm pad for it as well.  I added in the RO 150 so I had the aggressive sanding covered for large surfaces (tabletops, stairs and whatnot).  I already had the RO 90.  This combo has worked out great for me and have been using the 125mm pad exclusively.  That little bugger is aggressive with the right grits.  I think it works great for my workflow and very comfortable for what I do.  For larger surfaces the RO 150 works great for both aggressiveness and final sanding.  If I were you look at the size wood your working on and determine if you will reap the benefits of the larger surface area of the 150 type sanders. 

 

[leakyroof]

Did anyone show you the Aux handle that clips onto the front of the Rotex 150 if you need it?  Having that extra handle out in front can really tame the larger Rotex for extended sanding sessions or even vertical work since it changes the ergonomics of the machine greatly.
I have owned the ETS 150/5, and sold it off for the new ETS EC 150/5 sander when it came out. The loss of weight with the new design is a welcome relief for sanding walls and ceilings. That is a powerful sander, no Rotex, but a fantastic all-around unit as Peter noted. The older ETS is the same way with coarse grits allowing it to sand fairly aggressive, and still get very decent results with much higher grit sanding. Just taller and a bit more weight to it.
If you want to stay with one size paper and yet have the 'full' range of sanding capability, you could consider getting both the Rotex 150 and the ETS EC 150/3 sanders as a pair. The 150/3 will still sand more aggressive than you might think, be perfect for stain grade work and paint grade work and have that great small bodied sander housing that all of the new EC's have. But not tire you out at all.
Then, with the larger Rotex, you have really aggressive sanding in Rotex mode, stronger Random Orbit mode of 5mm orbit over the 150/3 EC sander to round out the range of possibilities.  If you're sanding level/horizontal work with the Rotex in Random Orbit mode, I don't count the extra weight of the sander as bad since you can let the sander do the work and just gently guide it around.

 

[Jmacpherson]

From the uses that you indicate the RO150 sounds ideal. Do not worry about wrist ache - I have quite severe arthritis in fingers wrists and elbows and I do not have any problem with the RO150 although I have never used it for more than a couple of hours non stop and only for short periods working overhead.

The ETS EC 150 takes the same sanding sheets as the RO150 and so if you can mange both then go for it. I really hope that your wrist condition is not worse than mine and assure you that with practice the RO150 is not difficult to handle.

Thanks Peter, my wrist flares up every now and then - repetitive strain injury my doctor calls it. Suppose it was rather silly of me to go play with power tools while my wrist was giving me trouble. It is only when I'm picking up the RO 150 that my wrist is feeling it.

I'm tempted by both because the ETS EC 150 feels so nice in the hand

 

[Jmacpherson]

i just went through this myself.  I found that due to my workflow about 80% of my sanding is on items that are 5" or narrower.  I ended up purchasing the ets 125 ec and bought the 150mm pad for it as well.  I added in the RO 150 so I had the aggressive sanding covered for large surfaces (tabletops, stairs and whatnot).  I already had the RO 90.  This combo has worked out great for me and have been using the 125mm pad exclusively.  That little bugger is aggressive with the right grits.  I think it works great for my workflow and very comfortable for what I do.  For larger surfaces the RO 150 works great for both aggressiveness and final sanding.  If I were you look at the size wood your working on and determine if you will reap the benefits of the larger surface area of the 150 type sanders.

Now you have thrown in the same spanner/wrench that the salesman I always deal with did regarding the RO 90  [laughing]
The 90 is looming in the back of my head with the delta attachment which has benefits when dealing with outdoor furniture.
It is the dark horse which is why I never mentioned it in the OP, worried about losing too much surface area but perhaps partnering it with an ETS could be an option

 

[Jmacpherson]

Did anyone show you the Aux handle that clips onto the front of the Rotex 150 if you need it?

..... you could consider getting both the Rotex 150 and the ETS EC 150/3 sanders as a pair. The 150/3 will still sand more aggressive than you might think, be perfect for stain grade work and paint grade work and have that great small bodied sander housing that all of the new EC's have. But not tire you out at all.
Then, with the larger Rotex, you have really aggressive sanding in Rotex mode, stronger Random Orbit mode of 5mm orbit over the 150/3 EC sander to round out the range of possibilities.  If you're sanding level/horizontal work with the Rotex in Random Orbit mode, I don't count the extra weight of the sander as bad since you can let the sander do the work and just gently guide it around.

I haven't seen the extra handle.

The 150/3 option makes a lot of sense instead of a 150/5 - 150/5 split for really fine work.

I'm still leaning very strongly towards a Rotex of some kind purely because I'm trying to refurbish a pine futon/couch that had no
more room for it inside so it was put outside by the pool. Was sort of under cover but it is the wrong wood to be exposed to the elements if not really, really, really sealed well. It is in relatively good condition, surprisingly.

Was purchased years ago and not sure what it was sealed and stained with. I've tried a Metabo SXE450 and isn't removing it.
Unless as Peter mentioned the right abrasive with the ETS 150 will do the trick?

 

[leakyroof]

Did anyone show you the Aux handle that clips onto the front of the Rotex 150 if you need it?

..... you could consider getting both the Rotex 150 and the ETS EC 150/3 sanders as a pair. The 150/3 will still sand more aggressive than you might think, be perfect for stain grade work and paint grade work and have that great small bodied sander housing that all of the new EC's have. But not tire you out at all.
Then, with the larger Rotex, you have really aggressive sanding in Rotex mode, stronger Random Orbit mode of 5mm orbit over the 150/3 EC sander to round out the range of possibilities.  If you're sanding level/horizontal work with the Rotex in Random Orbit mode, I don't count the extra weight of the sander as bad since you can let the sander do the work and just gently guide it around.

I haven't seen the extra handle.

The 150/3 option makes a lot of sense instead of a 150/5 - 150/5 split for really fine work.

I'm still leaning very strongly towards a Rotex of some kind purely because I'm trying to refurbish a pine futon/couch that had no
more room for it inside so it was put outside by the pool. Was sort of under cover but it is the wrong wood to be exposed to the elements if not really, really, really sealed well. It is in relatively good condition, surprisingly.

Was purchased years ago and not sure what it was sealed and stained with. I've tried a Metabo SXE450 and isn't removing it.
Unless as Peter mentioned the right abrasive with the ETS 150 will do the trick?

  For really aggressive stripping of a finish, Saphir will tackle many things. Or, Granat, which with certain  types of finishes will resist loading up very well.
Provide some pictures of what you're trying to remove with the Futon unit, might help us give advice.
For finish testing to learn about what you're working with, these are some tried and true solvents that help figure things out.  Lacquer Thinner applied to a Cellulose type Lacquer finish will remove it, but mineral spirits or something similar won't affect as much if at all.
A Varnish finish or something like a varnish or polyurethane finish probably won't lift up much at all when rubbed with Lacquer Thinner or Mineral Spirits like wiping with a cloth wetted as a test. This can be a harder finish to sand through as well depending on chemical makeup of the clear finish used.
Shellac, and I really doubt the Futon would even have it, can easily be played with by simple alcohol.
If the Futon just has a weathered stain finish, is your Metabo paper loading up with finish and causing you frustration that way?

 

[Jmacpherson]

....Provide some pictures of what you're trying to remove with the Futon unit, might help us give advice.
For finish testing to learn about what you're working with, these are some tried and true solvents that help figure things out.  Lacquer Thinner applied to a Cellulose type Lacquer finish will remove it, but mineral spirits or something similar won't affect as much if at all.
A Varnish finish or something like a varnish or polyurethane finish probably won't lift up much at all when rubbed with Lacquer Thinner or Mineral Spirits like wiping with a cloth wetted as a test. This can be a harder finish to sand through as well depending on chemical makeup of the clear finish used.
Shellac, and I really doubt the Futon would even have it, can easily be played with by simple alcohol.
If the Futon just has a weathered stain finish, is your Metabo paper loading up with finish and causing you frustration that way?

The wood that has been exposed to rain has weathered and was easier to deal with. Some more sanding, some wood reviver or something along those lines will get that back to a better state.
I can see some sort of "milky white" coating trying to lift off on the vertical sections but you sand it and it doesn't budge.
Perhaps the clear coat is the problem and that is what the sander isn't getting through.

I'll try different sections with different solvents like you suggest and see what happens.
Will take some photos tomorrow in daylight hours too and post them here.

Thx

 

[leakyroof]

....Provide some pictures of what you're trying to remove with the Futon unit, might help us give advice.
For finish testing to learn about what you're working with, these are some tried and true solvents that help figure things out.  Lacquer Thinner applied to a Cellulose type Lacquer finish will remove it, but mineral spirits or something similar won't affect as much if at all.
A Varnish finish or something like a varnish or polyurethane finish probably won't lift up much at all when rubbed with Lacquer Thinner or Mineral Spirits like wiping with a cloth wetted as a test. This can be a harder finish to sand through as well depending on chemical makeup of the clear finish used.
Shellac, and I really doubt the Futon would even have it, can easily be played with by simple alcohol.
If the Futon just has a weathered stain finish, is your Metabo paper loading up with finish and causing you frustration that way?

The wood that has been exposed to rain has weathered and was easier to deal with. Some more sanding, some wood reviver or something along those lines will get that back to a better state.
I can see some sort of "milky white" coating trying to lift off on the vertical sections but you sand it and it doesn't budge.
Perhaps the clear coat is the problem and that is what the sander isn't getting through.

I'll try different sections with different solvents like you suggest and see what happens.
Will take some photos tomorrow in daylight hours too and post them here.

Thx

  Milky White to me sounds like Polyurethane that's reacted with UV rays from the Futon being stored outside. Poly doesn't generally do well with UV exposure. Saphir or Granat  in the right grit should eat right through it. 60 grit or maybe 80 grit, hopefully you won't have to resort to 36 or 40 grit

 

[ajshobby]

i just went through this myself.  I found that due to my workflow about 80% of my sanding is on items that are 5" or narrower.  I ended up purchasing the ets 125 ec and bought the 150mm pad for it as well.  I added in the RO 150 so I had the aggressive sanding covered for large surfaces (tabletops, stairs and whatnot).  I already had the RO 90.  This combo has worked out great for me and have been using the 125mm pad exclusively.  That little bugger is aggressive with the right grits.  I think it works great for my workflow and very comfortable for what I do.  For larger surfaces the RO 150 works great for both aggressiveness and final sanding.  If I were you look at the size wood your working on and determine if you will reap the benefits of the larger surface area of the 150 type sanders.

Now you have thrown in the same spanner/wrench that the salesman I always deal with did regarding the RO 90  [laughing]
The 90 is looming in the back of my head with the delta attachment which has benefits when dealing with outdoor furniture.
It is the dark horse which is why I never mentioned it in the OP, worried about losing too much surface area but perhaps partnering it with an ETS could be an option

I don't have it yet but I am still thinking about the DTS also as an user friendly delta sander (another to consider).  I use the ETS as my main sander except for large panels now.  its just an all around comfortable enjoyable sander with lots of power.  I am glad I also got the RO 150 but I haven't found where I really had to have it over the ETS for normal everyday stuff.  The other festoolians on here were right on the money about the ETS EC as the best all around sander but should add that you need to stock a large selection of grits (60, 80, 120, 180, 220, 320 has been working for me).  the RO 90 dx has been sitting in its box unused of late except for a bit of delta sanding on occasion.  Probably will see more use in the near future as I have 2 kitchen cab jobs to do this winter and I like it for face frame work.

 

[Holmz]

...
The 150/3 option makes a lot of sense instead of a 150/5 - 150/5 split for really fine work.

I'm still leaning very strongly towards a Rotex of some kind purely because I'm trying to refurbish a pine futon/couch that had no
more room for it inside so it was put outside by the pool. Was sort of under cover but it is the wrong wood to be exposed to the elements if not really, really, really sealed well. It is in relatively good condition, surprisingly.

Was purchased years ago and not sure what it was sealed and stained with. I've tried a Metabo SXE450 and isn't removing it.
Unless as Peter mentioned the right abrasive with the ETS 150 will do the trick?

People make a lot of a fuss about the /3 versus the /5 strokes.
The /5 does remove stock quicker but it can do finish work. If you were in a shop with the sander running all day, then having multiple sanders is warranted.
I have a /5 DEROS and it finishes just fine. Whether the ETS/EC was inspired by the DEROS or not, it is a fact that they are very similar... Low centre of gravity, brushless, good handling, light weight, expensive.

If you are headed towards /3 then the 125 with an extra 150-mm pad is another option.

So far we do not know if the Metabo SXE450 sander is the problem or the sanding media.
The first thing I would recommend is getting a few different papers and running them on the existing Metabo SXE450 in order to see how different media works.
The Mirka Screens do come in a sample pack, which is a decent place to start this sort of comparison.
It may be that a different sanding media does wonders.

The second thing I would recommend is if you decide on an ETS/EC, then is there anything forcing you getting the RO-XX ? It is not like you get any discount buying 2 sanders. However you may get a discount with a sander vacuum combo.
Then run that sander and see what it cannot do before deciding on what problem yet another sander is solving.
Corners are an obvious place where a round sander does not excel. Whether that is a problem or not depends on if you have corners. Then you can decide on whether it is best solved with a DTS, 1/2-sheet or a different dedicated Delta head machine, or RO-XX.

The only thing I know for sure is that the ETS/EC is one of the few sanders (and a 1/2-sheet) where I could hand it to anyone and they would have no problem. Many have learned to handle the RO sanders, but that skill takes a while to get right. Also in non-geared mode the ETC/EC actually removes stock faster. Once you use the ETS/EC for a while then you will know whether you need something more aggressive or not. And then you will be better equipped to decide on an Ro or a RAS, or something else (planer, wire wheels, heat gun, etc). Maybe it will only take 2 weeks to figure that out, and maybe it will take longer.

 

[Jmacpherson]

Holmz, thanks for the insightful feedback and input.

I'm down in South Africa, unfortunately we are not spoiled for choice. Mirka is almost non-existent here.
Did some googling and I might have found an agent.

Even the full range from Festool isn't on offer here. Currently there are no RO 125's in country and they won't bring one in from Germany just for the demo. Ordering one to purchase from Germany is no problem. - This sort of makes me want to avoid a 125mm because it clearly isn't popular in our country so makes me wonder about accessories, pads, abrasives, parts etc.
The ETS EC 125/3 was just launched here and they have stock. My salesman called me this morning and explained about the RO 125 but told me not to worry, his boss owns a RO 125 personally and he will bring it in to the store for me to play around with so that I can compare apples with bigger apples as it were.

I don't need to get 2x sanders or have to/want to get 2x sanders. I'm pretty sure that most of the sanding I would need to do or even most of the sanding anyone does will be taken care of by an ETS EC. The unit will probably laugh at anything we throw at it.

As I mentioned previously ETS felt fantastic in my hand, probably the best sander I've ever held if not one of the best tools imho I've held.

My concern is the sanding that isn't covered in the "most", where the ETS might struggle or take a lot longer.
I've seen enough videos to see how quickly the geared mode of rotex removes material. That time saving is possibly what I'm after.
RO removing paint off siding (entire wall) in something ridiculous like 1-2min. I don't think an ETS will be that fast?

However how often am I doing that sort of aggressive removal?  Unfortunately, you guys cannot answer that for me.
I need to do some soul searching and thinking

 

[Jmacpherson]

Here are the photos of the futon...

The "sitting" slats have had the most exposure to the elements and were sanded with 60grit. As you can see there is still some sort of coating on the wood.

The "back" slats have had the least amount of exposure and were also sanded with 60grit. It hardly touched it.
There has been a gap since I last worked on it so I'm hoping my agitating the surface and the elements might loosen it some more.

On the one hand I'm tired of fighting with it. You sand and it laughs at you [unsure]
On the other hand will be fun to see if I can restore it and I get to practice sanding and restoration techniques.

 

[leakyroof]

Here are the photos of the futon...

The "sitting" slats have had the most exposure to the elements and were sanded with 60grit. As you can see there is still some sort of coating on the wood.

The "back" slats have had the least amount of exposure and were also sanded with 60grit. It hardly touched it.
There has been a gap since I last worked on it so I'm hoping my agitating the surface and the elements might loosen it some more.

On the one hand I'm tired of fighting with it. You sand and it laughs at you [unsure]
On the other hand will be fun to see if I can restore it and I get to practice sanding and restoration techniques.

  Can you show pictures of what abrasive you're using- and what the disc looks like on the Metabo once you've been at it a bit?  Might show the clogging that I'm expecting to see.
The Gray on the seat or 'sitting' slats means you're almost through your stubborn clear finish and into the sun damaged lignin of the wood, BUT, your sander seems to struggle even with that at 60 grit. So, I looked up what I think is your sander, a Dual Mode Metabo?  With a similar Rotex approach of 2 sanding modes, although the orbits don't seem to match what the Rotex sanders are capable of.
The fact that you could be one of the few owners of a 125mm Rotex if you bought it DOES make you wonder about supporting it with abrasives locally without having to ship stuff all the way from Germany... [blink] [blink] [blink]
So, thanks for the pictures that you provided, that helps a lot.

 

[Jmacpherson]

I'll take some pics of the abrasives I have for it.

From what everyone is saying the abrasives themselves might be too generic, rather use something more specialised to cut through the  protective coating first? It was the only range of 6-hole 150mm they stock. The RO 125 might be more common than 150mm sanding discs  [big grin]

The Metabo allows you to change the orbital stroke between 2.8 or 6.2mm via a button on the side of the machine. In theory it sounds great but in practice it has some bugs. I was warned about the unit that this function has problems and many people actually bring the unit in for servicing and they actually have the switch removed and leave the sander locked into one stroke mode permanently.

You need to decide which stroke rate you want before you begin. Don't try switching once you've been sanding for awhile, button gets stuck even if you follow all the steps correctly. I think the unit gets too hot and something expands because once it cools down the button pops out all by itself. It isn't a light green button

There is no geared mode like a rotex. There is a turbo button which speeds the unit up but it isn't going to compete with any RO model in geared-rotex mode.

Ironically it is actually heavier than a RO 150, only just.

 

[leakyroof]

I'll take some pics of the abrasives I have for it.

From what everyone is saying the abrasives themselves might be too generic, rather use something more specialised to cut through the  protective coating first? It was the only range of 6-hole 150mm they stock. The RO 125 might be more common than 150mm sanding discs  [big grin]

The Metabo allows you to change the orbital stroke between 2.8 or 6.2mm via a button on the side of the machine. In theory it sounds great but in practice it has some bugs. I was warned about the unit that this function has problems and many people actually bring the unit in for servicing and they actually have the switch removed and leave the sander locked into one stroke mode permanently.

You need to decide which stroke rate you want before you begin. Don't try switching once you've been sanding for awhile, button gets stuck even if you follow all the steps correctly. I think the unit gets too hot and something expands because once it cools down the button pops out all by itself. It isn't a light green button

There is no geared mode like a rotex. There is a turbo button which speeds the unit up but it isn't going to compete with any RO model in geared-rotex mode.

Ironically it is actually heavier than a RO 150, only just.

. Wow, good info. I had read that switching between modes could be problematic.

 

[Jmacpherson]

[member=10952]leakyroof[/member]

Managed about 10-15min or so before my wrist started bothering me, been giving me trouble all week.
Below is the 60grit sheet I used.
There isn't much build up that can see but the original colouring of the paper itself doesn't help detect it either.
At one stage there was lots of black spots on the once section of the pad ( I never took a pic), then I activated the turbo mode and the spots dissapeared.
Not sure if it is going to tell you what you wanted to know?

I did some more research on all 3x ETS EC models and if you get right down to it its pretty much the same unit underneath it all?
I also realised from my little exercise that 150mm sanders tend to not fit in everywhere on certain pieces of furniture.
The 2.4kg Metabo was awkward in places and vertically but granted its ergonomics are not in Festool's league.

Which has kind of made me think that an ETS EC 150/5 is the no brainer decision?
Going on pure instinct and gut and how it feels in my hand, it would be the one. Admittedly I haven't held a RO 125 or ETS EC 125 but the EC 125 should be exactly the same.
Logic tells me that @1.2kg, the 150/5 is the sander I'm going to reach for 90% of the time.

Due to my element of doubt and concerns about rapid material removal, assuming I like the feel of it, get the RO 125 and use it primarily for course sanding only. Then I only have to invest in 60/80/120 grit Granat/Rubin paper.
And since its stroke is 3.6mm should I need a finish finer than 5mm then I could use the RO 125 for that.
Would also extend its lifespan and reduce possible need for spare parts etc.

Its pointless trying to save cost on abrasives and sticking to the same pad size and then getting the larger unit and then I don't use it because its uncomfortable or I damage my wrist more in the long run which will cost more than sandpaper. Its just sandpaper.

Something else that crossed my mind today, if Festool are launching new brushless eccentric sanders of existing models, how long until a brushless rotex is launched? Perhaps it is worth waiting to see what they have on the horizon first?

 

[leakyroof]

If you've run the RO 150 for any extended time as a test, then please be prepared for the smaller RO 125 to be a bit more of a handful in Rotex mode than the larger 150.
Your sore wrist may rebel with the RO 125.....With that said, using any of the ETS EC sanders would be a one-handed affair and allow you to spare the ailing one from constant use unlike either size Rotex sander in Rotex mode since those sanders work best with two hands during aggressive sanding... [sad]
The Abrasive disc you've got looks like it's coated and not clogging with removed finish ,so that's a plus.  Unless there's something I'm missing with the Abrasive, seems like it's mostly the fault of the sander.... [scratch chin]