Riving knife problems

[Suresh]

I recently bought the Leda TSC-12HK, 12" table saw.
It has a riving knife that is mounted and slaved to the arbour. That is as the blade rises and falls so does the knife.
This is generally a good thing, except when the depth of cut is over 60 mm, then the shape of the riving knife makes it stand well proud of the blade. This is a real proble when making a sliding cross cut table to go on the saw. The riving knife stands well above the blade is a bugger.
The people from Leda suggest simply grinding the rive so that it is a lot lower, however this means that the blade does not have a rive when the depth of cut is small.

Any suggestions? I thought about making another riving knife for when the blade is high and leaving the current one for normal usage. This all seems a lot of bother, anyone else have similar problems?
Suresh

[derekcohen]

Suresh

Can you post a pic for us to see what you are referring to?

Regards from Perth

Derek

[Caliban]

Sorry if I'm ignorant (shut up Darren ) but who or what is Leda? Sounds like I really don't want to know. Do they sell a cheap and nasty version of everyone else's tsc- 12? One that has a crappy riving knife? Was it cheap by any chance?
Suresh, aren't you the one who tried to offer Goldleader a ridiculous price for some triton gear he had for sale? Is this fate?

[rev]

Suresh,

I had to fashion a riving knife for my MBS saw which I bought second hand missing its original riving knife. I made a couple from different thicknesses of aluminium - for regular and thin kerf blades.

To modify yours so that the knife still functions when the blade is low, but is not too highly elevated above the blade when the blade is raised, try the following:

1. lower the blade until the teeth are just below the surface of the throat plate.

2. Mark the riving knife at this height level with the table; Anything proud of the table now is unnecessary so cut off this excess.

3. Grind the top back corner part of the riving knife away so that the top ends up looking like a backwards shark fin - pointing forward behind or above the blade. (You can raise the blade and knife to its highest point to determine how much you can afford to grind off this top back corner.) DO NOT grind away any of the front point of the riving knife because that will render it less effective when the blade is low.

I hope this makes sense. If you have any problems picturing what I mean let me know and I can post some pictures in a day or so.

Cheers

[Justin]

Most crosscut sleds I've seen (including mine) don't operate with a riving knife fitted. I think you'll find that most people remove the riving knife/blade guard assembly when using a sled. I have a delta unisaw, and the design of the blade guard doesn't permit me to use a crosscut sled with it fitted.

IMHO, the purpose of a riving knife is mainly to prevent the timber closing up and pinching the blade during a rip cut. You don't have the same problem occuring during a crosscut (i.e when you're using a crosscut sled).

Cheers,


Justin.

[Suresh]

Derek,
I will post a picture if I can find the cable to my camera. I agree, the question would make a lot more sense if there was a photo to illustrate the issue, hopefully in the next day or two.

Hovo, I bought this particular saw because it was the only one which was approved by WorkCover because of its built in safety guards etc. it was hardly cheap, over 2.5k. I don’t have any Triton gear, apart from the router, what a great machine that is.

I was thinking of taking of the riving knife and making another one out of polycarbonate, this I can cut and shape on the bandsaw as I am not confident working with metal.
Suresh

[rev]

Suresh,

You can cut aluminium or steel with a jig saw (fitted with the right blade) and then file or grind the remainder to get a smooth finish.