I've been following this highly entertaining thread for some time now but I've tried to stay out of it because I can't in any way relate to the disappointment expressed here about the Carvex's cancellation/postponement. In that light the most sensible remarks in this thread were, in my humble opinion, made by Darcy (with screen name WarnerConstCo). After all, it's just a tool, nothing more, and there are many alternatives available.
It is not as if your new baby is stillborn.
It was also entertaining to read all the speculation about the reason why. Amongst a couple of 'out of this world' posibilities there certainly are some more plausible theories amongst them. The debate seems to center most on the on-board stroboscope. And that's where I'd like to add my 2 cents because unfortunately some people seem to be a bit off with their facts in this matter, Rick Christopherson being the most proliferant. And unfortunately some other people, looking upon Rick as an authority on Festool because of his manuals, follow up on his mistake.
Unlike others, I have no problem providing some links to back up my claims.
Rick Christopherson said:
As for the further speculation of a stroboscopic effect inducing seizures, this too doesn't stand to logic. In order for a stroboscopic effect to result in a seizure, it must occur at a frequency within visual perception of the human mind.
This is a bit vague. What is the 'visual perception' of the human mind exactly? Because when it comes to frequencies, the mind has an enourmous capacity for visual perception. For instance, it can distinguish with great certainty between different colours in light, colours that are detected by the retina of the eye and processed in the mind. Light is a form of electromagnetic radiation in the frequency range of 405 THz to 790 THz. THz stands for Tera Hertz, and Tera means a 1 with 12 zero's. That's a huge number.
That's way above the 10 Hz Rick mentions, and the human mind can perceive it perfectly.
Rick Christopherson said:
This means it must occur significantly BELOW 10 hertz
But let's stay a bit closer to home. After all, light's frequencies are a bit high and I don't think many people get seizures simply by opening their eyes. Let's look at the more sensible frequencies that computer screens use.
Everbody knows about computer screens. Everybody who bought them over the last decade knows that they have a refresh rate. And everybody knows that monitor refresh rates can influence you, causing fatigue, eye strain and headaches. These were most proliferant with older monitors that had a 60 Hz refresh rate. That's why over time the refresh rates have gone up from 60 to 75 to 100 and 120 or more. It is a well known fact that these refresh rates can have very prolific effects on people who are sensitive to them. Like
epileptics.
If those refresh rates affect you, it means your mind can perceive them. That puts the human visual perception up to 60-120 Hz already, also above but already a lot closer to the 10 Hz mentioned by Rick.
Rick Christopherson said:
However, the speed range of the tool is 500 sps to 3800 sps, which is far above the stroboscopic rate necessary to induce seizure.
And this is where Rick goes entirely wrong. First off, I don't know exactly what sps means. Tried to Google it but the only relation to frequencies I could find for this abreviation is Samples Per Second, and I don't think the Carvex has anything to do with music like my multitrack software does.
But we're talking Hertz here,and Hertz is measured per second, so I guess 3800 sps must mean 3800 Strokes Per Second or something like that. That would be some jigsaw, wouldn't it? That's an absolute beast! I'd buy that for a dollar! That would cut your 8x4 sheet in half in under 2 seconds. Think about the time and money saved!
Unfortunately the Carvex' rpm is 1500-3800 strokes per
minute which is 60 times slower. In Hertz, this translates to 25-60 Hertz.
And yes, 25 to 60 Hz is well within the range of photosensitive epileptics. Don't believe my word for it, believe the
University of Wisconsin or the
Epilepsy Foundation or
Epilepsy.com. Their consensus is that most photosensitive epileptics are susceptible for the ranges between 5 and 30 Hz, but some cases even up to 50 or 60 Hz. And that's precisely the range in which the Carvex' stroboscope pulses.
So if there's any theory plausible, it's this one. Or perhaps not. Perhaps there's some other mystery reason nobody thought of yet. Frankly, I care little. What is not plausible is that the Carvex is somehow not up to Festool's standards or has a technical defect 'specific to North America'. What a load of bollocks. If that were so, Festool wouldn't have released the Carvex in Europe and the rest of the world either. Yes, the Carvex had some teething problems, like a lot of new products have, but they've been adressed and the Carvex is a fully functioning product now.