Riving knife on circular saw?

[robgul]

As referred in another post I have an old B&D Proline saw - it's old but still works and despite being in the market for a cordless I've given the old one a reprieve and ordered a new blade for it to use pro tem.

One of the issues with it is that the riving knife moves a small amount from side to side and quite often doesn't engage in the cut as the saw moves forward (I would add that the rest of the saw, spring guard etc is mechanically fine)

I've seen that, probably, most current portable circular saws (corded and cordless) don't have a riving knife.

So the question is the wisdom of removing the riving knife . . . my cutting with this saw is just sheet material (max 18mm) and is always well supported and seldom more than a 1220mm cut length.

Views/comments?

 

[Daniel2]

My 2P,

There are two issues:

A/. The kerf closing behind the blade and jamming it, as you proceed.

B/. An increased risk of kickback. A result of A.

Would it be possible to shim, or otherwise hold, the riving knife in it's place ?

ATB,
Daniel

 

[Myfordman]

There should be no way that the riving knife can move with respect to the blade. Sort that out and the problem should go away.

 

[robgul]

... yes, yes BUT as I said it looks like most new saws today don't have a riving knife . . . . . is that good or bad?

I do understand what a riving knife does, there's one on my table saw.

[Having looked at the saw it seems that the riving knife mechanism on mine is beyond realistic repair - parts look as if they would need to be repalced, if you can even get them - I'm going to buy a cordless so money spent would be wasted. I think the machine must be approaching or perhaps more than 30 years old!]

 

[PAC1]

If you are only cutting made made board, then the kerf binding is not an issue. You can still get kick back. Am I right this is a hand held saw not a table saw? If so the next question is how good is the spring on the blade cover? Also do you use a track or freehand?

 

[Daniel2]

In that case I don't know, and would also like some enlightenment.
FWIW, I just looked at my cordless Hilti and that doesn't have a riving knife.
Having said that, it does tend to kick back sometimes.
Look forward to someone who does know coming along

 

[HappyHacker]

A few years ago I was working with a joiner on site and he said he had just bought a portable saw without a riving knife. I said I thought that would be against H&S guidelines but I am far from being an expert.

As I have had a couple of hairy moments when trying to cut fitted floorboards with a riving knife fitted, shuffling around on the floor on my knees does always enable the best control, I would not like to use one without. Plunge cutting with one is difficult though.

You know that you really really really need a track saw preferably with a retractable riving knife, you know it makes sense

 

[Inspector]

The saw in question is like the one in this eBay add. Black & Decker ProLine PL40 Circular Saw 1150w for sale | eBay

From the google search it seams like some parts may be available for it but I didn't dig that far. If you are ripping solid woods that can close and pinch the blade the riving knife is safer to have on. Sheet stock it doesn't generally seem to be needed. It would be a problem if plunge cutting. Lots of new saws don't have them so pulling yours off would be up to you. Until the advent of track saws they were never on circular saws here, not saying they shouldn't be but just aren't. If you did buy a track saw with one on it you would have for the most part the best of both worlds. Some of the track saw here don't have riving knives either.

Pete

 

[robgul]

To be totally clear - this is a hand-held portable, NOT table, saw - it's the same as this one currently on ebay :

https://www.ebay.co.uk/itm/BLACK-DECKER-PROLINE-SAW-/153457532659 [It's not mine but if it sells I might be tempted to list mine ]

I'm trying to remember when I bought it - it was from the Black & Decker shop that used to be in Bristol and must have been around 1986/7.

The spring on the guard is still very strong, which is good - I use it either freehand or running against a clamped-on straight edge (a length of timber or if the right length, an Axminster guide clamp) - depending on the work. My modifications are a longer cable and the dust port has been added to with a short length of plastic waste pipe glued on with epoxy - to which I can connect my dust extraction hose if working inside - if outside I don't bother.

I can barely recollect ever cutting anything other than at 90 degrees, and never plunging.

I do also have a track saw (no riving knife) and a table saw (with riving knife)

 

[large red]

I spent 20 years as a site chippie 1st and second fix and the first thing you did was take the driving knife off. They got in the way, saws got thrown about a bit, dropped, kicked and stepped on! The riving knife would suffer and clash with the blade. Never missed it.

 

[HamsterJam]

Festool fit a riving knife to the TS55......

 

[heimlaga]

The riving knife on my hand held cirkular saw once saved me 3 or 4 fingers. Those fingers are useful so I am happy they are still in their proper place and consequently I keep the riving knife in it's proper place too.
I would not buy a handheld cirkular saw without a riving knife. Absolutely not. Though some recent changes in the all-European regulations made them legal again.

 

[TheTiddles]

Mafell saws have riving knives, I think Festool do too, fairly certain Makita too

aidan

 

[robgul]

Cofusion reigns - a quick run through of all the cordless circular saws on the Screwfix website - brands : de Walt, Makita, Erbauer, Bosch and Milwaukee - has about 60% of the saws without a riving knife and 40% with - that's not brand specific, e.g. Makita has with and without, likewise I think Bosch.

Anyway - someone has given me an Aldi cordless circular saw today (BNIB - he got it in a bundle deal but already had the same machine) so I shall give it a go and see what happens.

The new blade for my old B&D Proline should arrive soon from Saxton Blades . . . . and I found very long extension lead in the shed today so I can use it at the end of the garden (a bit of power drop but not a lot) - along with my BIG corded drill.

Thanks for all the comments - even with the confusion

 

[Trevanion]

I've got an old (80s maybe) Hitachi somewhere that has a very loose riving knife seemingly by design that just flaps about left and right a bit.