Hi again
I think the guarding thing still boils down to a proper suspended crown guard - a device useable for almost all cuts. They exist now, are available in the aftermarket, and I can testify personally (as can many other woodworkers) that they are effective. They are also offered either as standard or as an option on every panel and most rip saws I know of.
Midnight":25f6nlyp said:
...The point I was making was that as their brake is FAR faster reacting than the 10 secs that the new regs impose, they MUST have had to find an effective blade retention solution.
Maybe they have, but their saws are no bigger than 10in whereas I (and many other people) use a saw with a 12in (or larger blade). The bigger the blade, the bigger the problem, and there a lot of amateurs out there using machines such as the Felder, etc. which come as standard with a 12in blade. As to using Nylocs, these are really designed for one-time use. In an average day I can easily have to change blades 8 or 9 times depending on work mix (of for a rip saw...) - that would mean 8 or 9 new Nylocs a day! (not cheap) As industrial machines now come with two extra pins on the arbor (and indeed have done so for about 8 to 10 years - German CE marking from 1994) why not extend that to all saws benches?
The SawStop has attracted some serious criticism in the USA for a couple of reasons, first it depends on the charge in the blade being discharged to earth which may or may not work if you are wearing gloves or rubber-soled shoes (and in any case how will that work 10 years down the line?) and secondly, surely you are depending on the machine to safeguard your safety when you should be depending upon your own safety assessment and training, first and foremost, and taking the appropriate primary safety precautions. It's probably analageous to the air bags vs. better driver training question in cars.
If a stack head cutter makes the kickback potential worse, why not remedy it by stacking splitters too….??
Or why not just choose a method which doesn't require the reinvention of the wheel? I think you may be trying to solve a problem which is much more easily resolved by simply choosing an alternative approach. A pro shop doing trenching would probably tend to look at using a crosscut saw (RAS) with a trenching (dado) head or a hand router/jig combination.
(chip limiter blades) As I understand it, the design physically limits your feed rate to that with the blade can handle safely by pushing the stock back before the cutter advances into the cut.
There is a major difference between chip limitation on a 60 tooth combination blade and a 2- (or at best 4-) tooth raker blade in the middle of a dado set. With only 2 or 4 teeth to clear the waste you either have to take a very shallow cut (say 5 or 6mm) or pass the work over the cutter very slowly (a more dangerous approach as kick-back is more likely to be encountered). Remember that here we are talking in the main about 1 or 1-1/2HP home shop machines - unlike the large industrial saws of 5 or even 10HP the small saws do not have the margin of power to overcome resistance in the cut and are more likely to stall or kickback during heavy cuts. As you correctly surmise power feeders are another solution used in industry - partly for reasons of safety, partly for reasons of improved throughput - but you can still experience kick-back with them if you are running an underpowered saw, it's just that the effect is less noticeable. However they won't be much help if you are trying to trench across the middle of a 12in wide board as you'd really struggle to hold the work at 90 degrees to the fence. Somehow I can't see many people here flashing out the £400 or so a full-size feeder and stand costs. Oh, and I do use feeders in the shop - on the spindle moulder and the edge sander (ripping tends to be done on the bandsaw) - they need to be set up with a few degrees toe-in against the fence to ensure straight feeding which makes them suited to ripping-type longitudinal cuts but not for feeding across the narrowest part of a board. They are, also, unfortunately too heavy to lug around between machines, especially at chest height, so they stay attached to the same machine all the time.
... All the more reason to tighten up specifications for throat plates....
But how do you deal with panel or dimension saws which have and can have NO throat plate? (I'd love to see how Felder have managed this on the K900 series for the USA) Sorry, Mike, still think you're trying to reinvent the wheel here :wink: Yes, you can make dado heads on a table saw safe - but at what cost? (and is it really worth it when there are other solutions already available)
Your comments about sub-bases are interesting. Elu used to make two routers for edging work which were specifically made with offset baseplates to address this problem - the MKF67 and the MOF 69. Balance doesn't seem to be too much of a problem with them, but then they are only 1HP routers. The MKF67 has been re-introduced as the DW609 and once more I can testify to the fact that these routers work and work well. So, why not try an offset baseplate for yourself?
As to router bit breakages - have you experienced any yourself? I have, quite a few over the last 25 years or so of router ownership, but I was only speaking from personal experience - with a dust extraction boot in place the broken cutter seems rarely to be ejected. Same goes for our pin router in the shop. Maybe I have been lucky.
These last 2 posts paint me as a thoroughly argumentative bugger at best.
Ermmm.... well, yes :lol: But then that makes two of us..... :wink:
I resent the fact that even if I took the time to retro-fit a machine with every bell and whistle designed to eradicate kickback, I STILL can’t legally use the cutter in a commercial application.
Not true. As I stated there is a
Duty of Care placed on employers (and in many cases on the self-employeed by their insurers) which requires us to take steps to ensure best working practice. I feel that the same approach should be considered by amateurs - after all none of us can regrow fingers after amputation...
One thing we can agree on, however, is the quality of most manuals.... Generally quite dreadful (including the Italian ones)
Have fun, stay safe
Scrit