Rotex - RO 90 - belt driven ?

[antss]

There's a discussion over in the problems section about the ro90 and whether or not it is belt driven or if the belt is just for the delta pad mode ?

Can one of you shed some light on the drive system for the 90 for us ?

 

[aloysius]

It's belt driven.  The belt is its best & worst feature.

 

[Shane Holland]

Yes, belt driven.

 

[TylerC]

Confirmed. Belt.

[member=9481]aloysius[/member]: I'm curious for your opinion on it being the "best and worst feature". Would you mind explaining?

 

[antss]

Thanks.

adding to aloysius' comment , I can think of a few off hand.

A belt is just something to wearout or fail prematurely. Faster than a geared connection at any rate.. I doubt it's an easy swap which means a trip to IN.  Should make it smoother than the geared drive though.

In the thread that sparked my question, there was the postulation that the spinning belt caused static which wasn't dissipated by a non Festool vac. 

 

[Michael Kellough]

Anyone had a belt fail so far?

 

[Shane Holland]

Anyone had a belt fail so far?

FWIW, when I worked at FUSA, I never heard of a belt breaking. And, I was plugged into the service department pretty well to stop on top of anything they were seeing.

I've put almost my full weight on the RO 90 during a demonstration and it didn't bog down and the belt didn't have any issues.

 

[waho6o9]

Belts stretch more than they break in my experiences.

 

[antss]

I'm not knocking it, simply pointing out what some may find as a drawback.

Belts do stretch wahoo, but they also break.  Just ask all those folks with interference motors that had a timing belt break on them.  Timing chains fail way less often.

Again, not nitpicking.  If designed properly, the belt could have a service life close to that of the motor itself.

 

[aloysius]

Confirmed. Belt.

[member=9481]aloysius[/member]: I'm curious for your opinion on it being the "best and worst feature". Would you mind explaining?

Where to start?  Do you want the good news first....?

The belt drive effectively isolates load & mechanical shocks betwixt motor & mechanism.  There's no longitudinal (inline) stresses on motor ball races or bushings.  The whole head assembly, sans motor, may be made proportionally shorter & more compact overall, enabling access to restricted areas.

The belt drive assembly needlessly complicates construction, making for probable longer-term reliability and longevity issues.  Not to mention the needless expense.  No motor in the head means no motor cooling fan, ergo less cooling to the eccentric/reciprocal gearing's mechanism.  The head's gear assembly runs hotter than optimum:  all mechanical eccentric or reciprocal drive mechanisms require some form of crankcase cooling or ventilation (gas, fluid or aluminium heatsinks).  The requirement for physical separation of belt tunnel and dust venturi needlessly complicates the assembly, compromises the ergonomic/centre of gravity/hand grip relationship, and makes the tool frustratingly unwieldy.

The dust tunnel's location is perhaps the tool's biggest flaw in my opinion.  Being necessarily low-set, there's virtually no "stepover" head offset like there are in comparable tools, making for access difficulties verging on uselessness in some situations:  stairs, pedestals and podia for example.

Perhaps the biggest problem of all is actually no direct fault or flaw of the tool itself, however:  it's just that the alternatives are simply so much better at what they individually do.  A Deltex makes for a far smoother, more compact, less tiring and more effective delta.

The Bosch  PDA240/GDA280, with their infrequently used but invaluable when needed slim sanding fingers are streets ahead in difficult accessability situations too.  Metabo's delightful little SXE400 random is an ergonomic triumph of smoothness, tireless performance and accessing tight concavities.

The big Rotexes are just better.  The "125's" head is little bigger, yet in both ROTary & EXcentric modes will outperform the "90", having over twice the surface area.  With the "150" the difference is about quadrupled.  What's the formula: 2 x pi r??  Or is that circumference?  I just remember from my road & bridge building days where if a culvert's diameter is doubled then fluid flow is quadrupled, and if halved the flow is quartered.  The Cross Sectional Area of an RO90's pad is slightly less than 1/4 that of an RO150.

Plus the little bugger is just too damned expensive!  Similar to a "125" in fact.  You could get TWO Bosch GDA's and THREE Metabo SXE 400's for the price.  Or a DX93 and half a RO 125.  To me it's what you yanks love to call a brainless decision.  A pretty dumb choice, indeed.

 

[Michael Kellough]

"You could get TWO Bosch GDA's" except that they're not available in North America.

The RO 90 may not be as good in Delta mode as the tools you praise but it's also a rotary tool that is outstanding in smoothing concave areas with a small radius. For that work the Metabo SXE 400 is the only option here and it is much slower than the RO 90 in the rough work stage.

 

[aloysius]

"You could get TWO Bosch GDA's" except that they're not available in North America.

The RO 90 may not be as good in Delta mode as the tools you praise but it's also a rotary tool that is outstanding in smoothing concave areas with a small radius. For that work the Metabo SXE 400 is the only option here and it is much slower than the RO 90 in the rough work stage.

You first point is valid.  They are no longer available;  not only in the new world, but in the whole world.  Bosch, like many other manufacturers it seems have successfully deluded both themselves and customers into thinking that an oscillating tool is now a viable abrader of softer substrates.  Idiots.  It isn't.  Nevertheless, there must be plenty of other quality deltas available in the peculiar voltage characteristics of the 3 north american nations.  Hitachi-Koki, Makita, Metabo, Flex, DeWalt, Draper, Einhell, AEG, Ferm, Sparky, Narex et al.?  Realistically, even a cheapie house brand will be a better buy simply by virtue of superior ergonomics and compactness.  Then there's Festo's Deltex, which is just a much, much more useful (or rather "less useless") tool.

To suggest that a tool is not available locally is maybe a mite disingenuous.  Maybe it can't be purchased at your local corner store, (neither can a Festo) but just about anything as small, lightweight, inexpensive and globally available as a (hand-held) power tool is mere days away from your doorstep.  I've bought products as diverse as lawn mowers and jackhammers internationally through mail order.  I'm also led to believe that this is how many lonely men in the western world acquire their spouses these days!

You're quite correct in stating that in ROTary mode Festo's 90 will abrade more rapidly than Metabo's little SeXE, but only in the less restricted areas of a less than rectilinear form that it can actually access.  Any larger Rotex sander will be correspondingly more rapid again. Maybe for you it's different, but I've found the Festo 90 to be a particular poor performer in accessing many forms of concavities.  The silly dust ducting effectively precludes access, to the point of uselessness in many cases.  Alternative rotary tools will do the job so much better.  At almost ludicrously reduced prices too.  A basic arbour fitted to any old drill with a 50mm wobble pad will be more effective despite costing mere pocket money.  An Arbortech Turboshaft or Contour Random Sander both comprehensively address not only the accessability issues, but have an abrasive appetite for wood that makes all others pale in comparison when used in freeform carvings and the like.  They have quite justifiably won high praise in the process.  I could purchase some TEN of either of these for the price of Festo's 90.

The Festo Rotex 90 is in fairness a reasonably good tool in its own right.  Fairly well designed, but fundamentally flawed in its execution and also comprehensively outperformed in every single one of it's (albeit versatile) functions by more specialised & much less expensive alternatives.

 

[Michael Kellough]

These are very good comments aloysius! I hope you add them to threads with more appropriate titles or start a new thread so people looking for tools in this category in the future can find your comments.

 

[TomE]

RO 90 five years old now, no broken belt to date and still going strong.

First use was to prep-up of roughly 4000sq ft of wood lap siding and a bunch of wood sashes for repaint on a 50+yr old house

Powered off of 75' of 12g extension cord through an 11 year old CT22 with an additional Festool 452885 hose in line.

Used a heck of a lot of granat product and several vac bags. Some aggravation with dust chamber above the pad packing up some but clearing just became a regular maintenance thing with disk/delta pad change overs, dust collection was still good through out.  Static? None that I was aware of and I assume that the well pump house outlet I was using was well grounded. (the 452885 hose is listed as not anti-static)

I found the tool robust and ergonomics fit my grip just fine whether on ladders or knees once the hose position was figured out.... usually over the shoulder or strapped to my belt.

 

[leakyroof]

"You could get TWO Bosch GDA's" except that they're not available in North America.

The RO 90 may not be as good in Delta mode as the tools you praise but it's also a rotary tool that is outstanding in smoothing concave areas with a small radius. For that work the Metabo SXE 400 is the only option here and it is much slower than the RO 90 in the rough work stage.

You first point is valid.  They are no longer available;  not only in the new world, but in the whole world.  Bosch, like many other manufacturers it seems have successfully deluded both themselves and customers into thinking that an oscillating tool is now a viable abrader of softer substrates.  Idiots.  It isn't.  Nevertheless, there must be plenty of other quality deltas available in the peculiar voltage characteristics of the 3 north american nations.  Hitachi-Koki, Makita, Metabo, Flex, DeWalt, Draper, Einhell, AEG, Ferm, Sparky, Narex et al.?  Realistically, even a cheapie house brand will be a better buy simply by virtue of superior ergonomics and compactness.  Then there's Festo's Deltex, which is just a much, much more useful (or rather "less useless") tool.

To suggest that a tool is not available locally is maybe a mite disingenuous.  Maybe it can't be purchased at your local corner store, (neither can a Festo) but just about anything as small, lightweight, inexpensive and globally available as a (hand-held) power tool is mere days away from your doorstep.  I've bought products as diverse as lawn mowers and jackhammers internationally through mail order.  I'm also led to believe that this is how many lonely men in the western world acquire their spouses these days!

You're quite correct in stating that in ROTary mode Festo's 90 will abrade more rapidly than Metabo's little SeXE, but only in the less restricted areas of a less than rectilinear form that it can actually access.  Any larger Rotex sander will be correspondingly more rapid again. Maybe for you it's different, but I've found the Festo 90 to be a particular poor performer in accessing many forms of concavities.  The silly dust ducting effectively precludes access, to the point of uselessness in many cases.  Alternative rotary tools will do the job so much better.  At almost ludicrously reduced prices too.  A basic arbour fitted to any old drill with a 50mm wobble pad will be more effective despite costing mere pocket money.  An Arbortech Turboshaft or Contour Random Sander both comprehensively address not only the accessability issues, but have an abrasive appetite for wood that makes all others pale in comparison when used in freeform carvings and the like.  They have quite justifiably won high praise in the process.  I could purchase some TEN of either of these for the price of Festo's 90.

The Festo Rotex 90 is in fairness a reasonably good tool in its own right.  Fairly well designed, but fundamentally flawed in its execution and also comprehensively outperformed in every single one of it's (albeit versatile) functions by more specialised & much less expensive alternatives.

.  So we gather you're not a fan of it.... [wink]
I can not agree with almost any of your comments...and I own both the RO 90 and the Metabo SXE400.  Haven't seen that Bosch Sander in a few years or tried it out, sounds interesting though.
The belt issue is a non issue to me since both of my floor sanders use one to power the sanding head off a remote motor on the tool or machine. 
From what I've seen of many sanders, any cooling fan mounted is to cool the electric motor powering the tool, never an angle drive or gearbox that the motor is powering.