riving knife on table saw

[Ttrees]

Thanks Mike
I was actually going to make another knife if my guard design works, as it might make an improvement
for the dust extraction.
I mentioned on another thread, my idea of having the guard swivel instead of fixed.
I was thinking of making it in the style of the Axminster guard ...
This would accommodate blade tilting while the other 90 degree side, would enable the guard to be close to the fence.
Don't know if it will work, but its worth a shot.
Just have to make a switch first ...

It is surely a scary machine, I get frightened a bit, even turning it on....
I get the same reaction with it, as my friend did when I powered up my 24" bandsaw

I don't know why anyone would even consider using one without a riving knife :shock:
The noise itself just says beware !

Tom

 

[woodbrains]

Hello,

That riving knife looks fine, your guard idea should work fine. It is infinitely better than a crown guard attached to the riving knife.

Nice Startrite tablesaw, by the way. They actually run nice and smoothly, you should feel confident using it, and good guarding helps this.
Mike.

 

[Ttrees]

Cheers Mike
Nearly done with this tablesaw project
I spent quite some time on it
Chased my tail for about 10 hours getting the blade parallel with the table slots ....
using an adjustable square, picking a tooth and moving the blade over the other end....
It was perfect allready and there was just some crud on the blade and/or the washers that was throwing everything out of alignment.
I thought I had a bent spindle for a bit , luckily everything is perfect ....phew!
Spent another while making the fence parallel to the blade.
A combination of biscuit tin shims squares under the fence mounts and a bit of lapping the opposite corner mounts
I wonder how the fence rails was so out, yet, the table was so accurate ?
The fence seems like a good design so far despite what I've read
Tom

 

[Steve Maskery]

I have a shop-built SUVA-style guard on mine, you can see it on plenty of my YT stuff.

The issue you will will face is one of rigidity. Anything that is mounted a long way from its own position needs a rigid mount if it is not going to flex in use. I've seen such guards on enormous professional kit, mounted on huge 4x2 box sections, that flex more than I would like.

I overcame the problem by mounting the arm on the far right corner of my saw, but putting a U-shaped support on the top surface of my fence. In this way the arm is supported, not just at its mounting point, but also at the fence position too, which is usually much closer to the blade. The only time it failed was when I forgot to make sure it was adjusted correctly. It was loose, it made contact with the blade first and then my finger. It was a Very Ouch moment, I can tell you.

 

[Ttrees]

Thanks for your input Steve
I wanted the arm to be removable, as I could utilise the table extension for a router setup, maybe sometime in the future.
I was thinking of stiffening things up a bit, the horizontal U-channel flexes a bit, could be fixed hopefully, I'll have to see how it goes.
Tom

 

[Ttrees]

I forgot to ask ...
What height do you guys reckon this guard crossbar should be ?
I have left it this height, but plan to cut the U-channel post that's not too visible in this photo.
This will let the grey sliding exercise attachment part drop a bit.
It is able to swing out of the way just so you know.
I seen on another website, a dude who upgraded his saw which had an Excalibur guard on, and then he bought an Excelsior guard which was lower by a fair bit.
I asked him, but I got the feeling he didn't wish to give me bad advise.
Thanks
Tom

 

[Steve Maskery]

What is the max depth of cut of your blade? The underside of the support arm must be at least that far above the table.

Incidentally, I suggest that you design your system so that the whole arrangement can be quickly removed. There are some operations when the guard is not very convenient. For example, my blade tilts to the right, so for bevels, I prefer to have the fence on the left, so that the blade tilts away, thus not trapping my workpiece. In that situation, I have a magnetic stand-alone guard to take its place. Between the two I can so just about any operation and still have my blade properly guarded.

 

[NOTTNICK]

I don't think I'll be needing a guard on top as there will be timber over the blade when cutting.
It's a few weeks yet so I'll have time to experiment first.
Cheers
Nick

In this case you should use a guard both on the side and top of timber being machined (areas exposing the rotating cutting edge) and one type of guard is a (pressure) shaw guard, which will help hold the timber in place when machining and protect you from coming into contact with the revolving blade. If for any reason the blade is exposed with no guarding then you could touch it by accident, guarding is really sensible to use.

Mark

First - interesting to see the dialogue I have initiated!
I have a lot of food for thought now.
An interesting aside on same subject- I am soon to make a lean to Victorian type greenhouse, hence my query about grooves etc. on my saw.
I was looking on Youtube for some guidance on making the casement windows and EVERY video I looked at was using exposed blade with no knife or guard!
Some were really scary!

 

[Ttrees]

Thanks Steve
My 275 has a 105mm cutting height, but I've heard of folks using 14" blades in it, at full height, as it fouls something
inside if the blade is lowered.
I am hoping to fabricate a guard to do all in one, so that the blade will be guarded while it's tilted .
and being able to swivel 180 to have it tight to the fence for narrow 90 degree rips
The whole thing can be detached from the vertical post in about three seconds, this post is under the table height to enable use for a router table extension setup.
I just wish to know if I'm overseeing something, as I have only ever used a tablesaw (this one) a few times.
Having seen some guards different heights I wonder why ?
Is there any situations where this would be beneficial.

I still have not sourced parts for this swiveling part of the guard, but I'll probably find something suitable.
The idea makes sense to me, especially since I've got another Italian machine which has dual tilt function
Thanks
Tom

 

[meccarroll]

I got a kick back once, and swore it wouldn't happen to me again. This was a very long time ago, in my employers workshop, which was a signmaker's, rather than a proper cabinetmaker's shop. The tablesaw was shared with anyone who needed to make cuts, and as a consequence, people left the saw in a terrible state. Some used to regularly cut 8 by 4 sheets of ply freehand with no fence, guard or riving knife. So here I come trying to make something in my lunch break, so time being of the essence, didn't waste any by refitting the knife/guard. Anyway, I got hit in the eye by a lump of oak; luckily my cheekbone, eyebrow and nose took the main impact, and my eye survived fine. I had stitches in my eyebrow, and did look like John Merrick for about a week.

This is why I specified one man workshops in my posts. H&S regulations were designed for the sort of workshop you describe Mike. Unfortunately they ignored them!

Chris

Hello,

Yes, I know one man workshops generally don't always follow strict H and S rules, as they don't legally have to.
Mike.

One man workshops (The Self Employed/One Man Businesses) are also subject to the Law (Health and Safety). This is a useful read: http://www.hse.gov.uk/pubns/priced/l114.pdf.

An extract from the above PDF:

(2) The requirements imposed by these Regulations on an employer in respect of work equipment shall apply to such equipment provided for use or used by an employee of his at work.
(3) The requirements imposed by these Regulations on an employer shall also apply—
(a) to a self-employed person, in respect of work equipment he uses at work;

If you disagree then please let me know as I'd be interested to hear why.

Mark

 

[Mr T]

One man workshops (The Self Employed/One Man Businesses) are also subject to the Law (Health and Safety). This is a useful read: http://www.hse.gov.uk/pubns/priced/l114.pdf.

An extract from the above PDF:

(2) The requirements imposed by these Regulations on an employer in respect of work equipment shall apply to such equipment provided for use or used by an employee of his at work.
(3) The requirements imposed by these Regulations on an employer shall also apply—
(a) to a self-employed person, in respect of work equipment he uses at work;

If you disagree then please let me know as I'd be interested to hear why.

Mark

Well you've got me there Mark! I cannot disagree, it's there in black and white. Not sure it will change my practice when doing my own work on my own in my workshop. ie making an assesment of the risk and taking appropriate measures. I'll let you know if a H&S inspector calls to tell me off or if I seriously injure myself.

Chris

 

[woodbrains]

Hello,

It is simply the fact that no one makes checks. If my saw takes more than 10 seconds to stop, will I go to the expense of getting a DC brake fitted when no one will check? Similarly foot operated e stops and keyed isolators are legally required, but which one man band has them fitted if they don't want to. One man operations are simply beyond H and S jurisdiction. Similarly one man bands can pay themselves less than the minimum wage, no one cares!

Mike.

 

[meccarroll]

Hello,

It is simply the fact that no one makes checks. If my saw takes more than 10 seconds to stop, will I go to the expense of getting a DC brake fitted when no one will check? Similarly foot operated e stops and keyed isolators are legally required, but which one man band has them fitted if they don't want to. One man operations are simply beyond H and S jurisdiction. Similarly one man bands can pay themselves less than the minimum wage, no one cares!

Mike.

Mike, I see you still say the self employed business (one man operation) is beyond H&S Law, Jurisdiction. I can't say I'd agree with you on that but you are entitled to your opinion and I respect the semantics.

"................ If my saw takes more than 10 seconds to stop, will I go to the expense of getting a DC brake fitted when no one will check? Similarly foot operated e stops and keyed isolators are legally required........................."
Mike.

Emergency stops and isolation of woodworking machinery, now that would be a fair subject to discuss in another thread, Mike. :?

Mark

 

[Mr T]

Since Mike's post about emergency stops I've had a quick look to see if they are "required" and it seems a bit vague, but then I clearly don't know the regs as well as others. So if anyone wanted to start a thread on this I would follow it with interest.

Chris

 

[woodbrains]

Since Mike's post about emergency stops I've had a quick look to see if they are "required" and it seems a bit vague, but then I clearly don't know the regs as well as others. So if anyone wanted to start a thread on this I would follow it with interest.

Chris

Hello,

Yes, it is a bit vague and it seems it varies with circumstances, but gosh only knows what circumstances! In school, where I suspect the full H and S spectrum is applied, any fixed machine ( bolted to a bench etc.) needs a switched isolator, even if it can be unplugged from the wall socket. :duno: :duno: :duno:

It is complicated but I know of no one man operation that does comply to regs, or is ever taken to task over it, and that includes LEV testing.

Logically, why wouldn't​ hobby workshops need to comply, too?

Mike.

 

[Finial]

Hobby workshops don't have to comply with health and safety at work legislation because there is no 'work' done in them. 'Work' being commercial activity. If someone makes stuff for sale, that's work. There's no health and safety get-out for businesses of any size as far as I know. The only thing that self employed people are exempt from is welfare law, so they don't have to heat the workshop or provide a lavatory if they don't employ anyone.

But enforcement action is minimal, so many businesses make little effort to comply. They have other priorities. Usually they get away with it, but sometimes something goes wrong.