Hi Sinbad. +1 what others have said about your work.
My thinking on this is pretty much in line with the comments of others.
(A concern for me in all of this is, that the technician in the Festool Service Center (Woodcraft, Honolulu) showed no ‘technical empathy’ for what you querying – quote “...and the tech. said there is nothing wrong with it and showed me a new one that does the same thing...” end of quote.
And they just left it at that??
Wondering what they really know about Festool products – or how sanders are supposed do their work.)
1/ Sander needs to be ‘broken in.’ Will (might) sort it out.
(imho: would be better if the lower wattage sanders, in particular, were run-in before being put on sale. Or, at the very least, a big advisory sticker put onto the sanders.)
2/ Suction. Comments made about suction spot on. Seem to remember reading a post, where someone reduced the airflow even more – can’t recollect how they did that – maybe drilled a hole in the hose or something. Depends on the job in hand of course – is the pad over the edge of workpiece etc.
3/ Power. Some think the sander would benefit from a little more.
4/ Technique. Reckon this falls, big time, into the ‘teaching granny to suck eggs’ category; so not going there.
You’ve obviously become very familiar with the old PC ROS (indeed ‘at one’ with it I guess) and I speculate more powerful than the ETS, and, perhaps bigger? (just curious – what is the ‘sanding stroke’ of the PC sander?) Might that familiarity have coloured your expectations of the ETS?
In this context, wonder if the ETS 150 3mm would suit) The R0 90? The 30 day returns policy might be useful if you wanted to try them out.
That said, you’d think the ETS 125 was almost purpose made for just what you’re doing.
(Fwiw – a reconditioned 125 was my first Festool (no dust extractor at that point) and was used to sand down the wood frame of a very large balcony (with a couple of windows in it as well) with grotty, weather beaten, badly flaking old paint. Can’t remember now what grit started with, but modestly low – perhaps 80. Just let sander do its job. No problem – in fact, compared to what I was used to, a very pleasant experience. Soon moved onto a RO150 with Midi dust extractor though.
It can do more than some give it credit for is my message I suppose.)
Festool support in USA appears 2nd to none. Shane is on it – Festool USA will get it sorted if something else amiss.
Would be really great if you’d let us know how you get on – and what your thoughts are, with whatever sander you end up using. In my eyes, you are at the cutting edge in the usage of such sanders.
Richard.