DTS/RTS vs. ETS

onocoffee

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I was reviewing Festool USA's website a noticed a detail about the RTS/DTS 400 vs. the ETS 125. The website notes that the DTS/RTS are Orbital Sanders, while the ETS is listed as a Random Orbit Sander. I had been under the presumption that all three were the same, just with a different shaped sanding pad.

Am I correct in understanding then that the DTS/RTS produce a finer sanded finish than the ETS because of this difference?
 
I was reviewing Festool USA's website a noticed a detail about the RTS/DTS 400 vs. the ETS 125. The website notes that the DTS/RTS are Orbital Sanders, while the ETS is listed as a Random Orbit Sander. I had been under the presumption that all three were the same, just with a different shaped sanding pad.

Am I correct in understanding then that the DTS/RTS produce a finer sanded finish than the ETS because of this difference?
Umm, firstly ... not sure you would want that rectangular pad rotating on you .. RO forces a circular pad ... so about those corners ..

On topic. Orbital(-only) sanders rely on you moving them around - they should never be kept at the same place as otherwise they will "dig in" at the place you leave them. This lack of self-movement is also what makes them "finer" sanders /as compared to an RO/ at the same orbits, but not directly. It is because the user does and controls all the sander pad movements with an orbital-only sander, sans the orbital motion itself, the user can also make the movements very fine and soft, giving the stock a very light touch. Something that is impossible with a random orbital. If you ever try sanding an edge or a curve, this is where it is the most pronounced - basically any time the RO sander lacks the "bite" to prevent it turning into a momentary "rotating sander".

With RO, the pad is rotating (randomly) thus you cannot control it - it makes it "easy" as the pad is less likely to dig in, when in constant contact with the stock, but also removes your ability to fine-tune the pad movement/sanding speed etc. and introduces the "problem" of the pad starting to rotate the moment it loses contact with the stock - turning into an aggressive rotating sander for a split moment ..


Random orbit will generally always be better than just orbital. Smoother finish, less marks.
No intention to offend. But this is true only with an inexperienced and/or inattentive user.

For someone used to orbital sanders, it is the random-orbital that is the more (relatively speaking) marring/rough mark/dent-risky tool. Reason being that should one not be careful-enough, the pad can random-rotate itself too much when unloaded and then create deep dents as it hits the surface and slows down. This is not an issue with a pure orbital sander and is why they are "seen" as more suitable for fine work. Not because of their lower material removal rates. As for smoother finish .. I presume you never worked with a well-balanced half-sheet of the RS2 variety.

...
Hope helps, I am sure there are 17 other aspects I skipped in trying to prevent a novel developing on me ..
 
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Could it be said that using a RO with just the outer rim in contact (skewed) mimics the way an orbital sander works? It does take off more material that way…
Orbital sander pad does not move - it only "rotates in place/in its orbit/".

If you wanted to "mimic" a Random-Orbital sander acting like an Orbital(only) one, the easy way is to pin the pad by hand so it cannot rotate on the sander ... cause, well, that is the only difference between them as far as sanding goes.

On your note, it is the exact opposite. Sanding "by the edge" approximates a rotating sander like the RAS was, though probably closer to a compound rotation one like a ROTEX in its effect. An orbital-only sander is on the opposite end of the spectrum - the pad not moving at all, just orbiting "in place".
 
I think there is a confusion of terms here.
Random Orbit is not the same thing as what a Rotex does. It is a dual mode sander.
That locked mode is what is known as "Geared Orbital." It spins and wobbles around on small circles at the same time.
When it is unlocked, a Rotex works as a regular random orbital. It spins too, but the orbits are not forced, they can randomly skip the orbit. That's how they can make pigtail scratches. A geared orbital literally cannot do that, it acts more aggressive, like a grinder.
The ETS is a simpler version that cannot lock into the geared orbital mode.
The DTS and RTS do not spin. All they do is orbit/oscillate in small circles. It feels somewhat like vibration, since the circles are so small. They don't really "randomize" since it's just a cam driven excentric driving the pad.
 
But adding the Random to Orbital sanders was done precisely to give a smoother more swirl free finish.

About the only sander I don't have is the DTS, and I use them all on faces and to round over edges, in fact on all the charcuterie boards I make I use the ETS EC's to round over all the outside edges.
 
But adding the Random to Orbital sanders was done precisely to give a smoother more swirl free finish.
That is true, but only if you use it correctly. You definitely can make swirls with a random orbit sander.
Too much force applied has a lot to do with it, along with incorrect grit.
Geared orbitals are much more aggressive, but that action comes back to helping again, with super fine grit. At that point, they polish, something that random orbits don't do so well.
"Technically" the RAS is considered a sander, but it's not even close to what most people would use it to do. It is effectively a grinder, that uses sandpaper, rather than grinding wheels.
 
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