table saw ripping timber

[user 19915]

I have a iroko window sill about 7 in wide i would like to thin down as one side as cement and glue and is a little rough so could i rip it down on the table saw and then top and tail it and do the other side ? I f so how accurate would the cut be ? also does the riveting knife stay on the table saw or should i remove it for the job
Alan

 

[woodbrains]

Hello,

Never remove the riving knife! If it stands above the saw blade height, then you can't do what you propose, unless you can shorten it, but don't remove it. Deep cutting with two passes of the tablesaw is dodgy, at best, but a partial cut without the riving knife is asking for trouble. Tension in the wood will pinch the saw blade and stop your motor, burning it out, if you don't get to the off switch in an instant. Do you not know anyone with a bandsaw that can help you out, although if the wood is full of debris, they would likely have to sacrifice the blade.

Mike.

 

[MattRoberts]

Top and tailing is fine if you have a riving knife and a good blade and you take it slow

Also remember : you only need your blade height a shade over half the height of the timber you're ripping

 

[woodbrains]

Top and tailing is fine if you have a riving knife and a good blade and you take it slow

Also remember : you only need your blade height a shade over half the height of the timber you're ripping

Hello,

It is not 'fine', it is doable in a pinch, but seriously, I would avoid doing it as a matter of course. Partial thickness cuts should be avoided unless special guarding is devised to do it safely. By the time such a device has been designed/built, it usually negates the 'convenience' of ripping like this. This usually means no guards are used, for a one off job. If you think it is 'fine' exposing 3 inches of rotating circular saw blade with no guard and hand feeding the timber through on its narrow edge, then you have clearly never witnessed an accident....yet!

Mike.

 

[MattRoberts]

Hello,

It is not 'fine', it is doable in a pinch, but seriously, I would avoid doing it as a matter of course. Partial thickness cuts should be avoided unless special guarding is devised to do it safely. By the time such a device has been designed/built, it usually negates the 'convenience' of ripping like this. This usually means no guards are used, for a one off job. If you think it is 'fine' exposing 3 inches of rotating circular saw blade with no guard and hand feeding the timber through on its narrow edge, then you have clearly never witnessed an accident....yet!

Mike.

As always it's a balance between a variety of factors : the size and shape of the timber, the precision of the fence, the depth of cut, the sharpness of the blade and the confidence of the user.

I'm the first to advocate safety with power tools (especially a table saw), however some people are so over cautious on here they think a saw can't be used safely without a blade guard and all the trimmings.

 

[sunnybob]

Matt, I'm kind of siding with woodbrains, for one reason only.
Presumable you dont know this guy. You dont know his skill level, you dont know if he's accident prone. you dont know if he's a troll and just looking for someone to sue.

Giving advice blind, you should always Cover Your Arse and recommend the proper way. Its OK to say "well this is what I do but I cant recommend it". Not good to tell someone online how to cut corners.
We all do dangerous things (oh yes, i do!) but you are leaving yourself wide open to a compensation claim putting in print that guards are optional extras.
OK, lecture over, normal service is now resumed.

 

[memzey]

Having said all of that, all the guards and gizmos in a machine's arsenal are no substitute for user inadequacy. I'm always a bit concerned when people say "use xyz and you'll be fine" when really the user must have his wits about him/her at all times when using such machinery. Guards may reduce the likelihood and/or impact of an accident but the most critical factor in safety (in my limited experience at least) is acting prudently.

 

[heimlaga]

I make those partial cuts all the time. Nothing wrong with that........ but I fitted my combination machine with a low riving knife and a home made overarm guard. That is as cloe to industrial safety standards as I could get.

Those riving knife mounted guards mounted on high riving knives are utterly awkward to use. The whole saw is destroyed. Impractical guard end up on the scrap heap where they don't protect. Hence I am an advocate of overarm guards.

 

[MattRoberts]

Matt, I'm kind of siding with woodbrains, for one reason only.
Presumable you dont know this guy. You dont know his skill level, you dont know if he's accident prone. you dont know if he's a troll and just looking for someone to sue.

Giving advice blind, you should always Cover Your buttocks and recommend the proper way. Its OK to say "well this is what I do but I cant recommend it". Not good to tell someone online how to cut corners.
We all do dangerous things (oh yes, i do!) but you are leaving yourself wide open to a compensation claim putting in print that guards are optional extras.
OK, lecture over, normal service is now resumed.

I'd be surprised if any court of law would accept a forum post from a random person as legal culpability for someone's accident, however I take your point and appreciate you're looking out for me

To any readers : Please accept my posts as anecdotal, and any use of them is at your own risk! If you're unsure about making a cut in a certain way, don't make it! Better to be safe than sorry

 

[user 19915]

Sorry for all the debate i do understand both sides of the discussion regarding suing you as i am sorry to say that,s how the world as gone crazy : Better safe than sorry i suppose But back to the topic thank you Matt and others for answering my question. So any information i receive on this forum i do not take as common practise but only your opinion on answering my questions thank,s Alan

 

[sunnybob]

you cant get more common that our practices! But it is a subject that needs to be in peoples minds when giving advice.

Remember the famous case of the american camper van owner who engaged cruise control on his brand new van and then got out of the seat to make coffee. He won his court case after the crash because the instruction book didnt tell him he couldnt.
That makes us lot positively wild, doesnt it?

 

[woodbrains]

Hello,

I have to have a wood machine safety certificate for my job. Sometimes the industry standard is not necessarily applicable to home hobbyists, but some are good sense too. Partial thickness cuts for rebating for instance, are not allowed in industry if the crown guard is removed, unless some sort of tunnel guard is employed, riving knife fitted, too.

Clearly, home woodworkers do these cuts, just running the board against the fence, hopefully taking care and realising the risks involved. Deep cutting in two passes, however, is just too risky. Things happen awful quickly on a TS and balancing a board on edge, with 3 inches of rip blade embedded in the cut, the user cannot see what is going on. Just a slight bow in the board, imperceptible, but enough to cause all sorts of binding and burning, then bang it catches. There is nothing you can do against a few horsepower and 24 teeth spinning at 4000 rpm. My blood runs cold.

To be honest, the rip cut done this way is going to need a fair bit of planing true. Why not just scrub off all the muck with a stiff brush and warm soapy water. When dry, it will probably need less of a go with a plane to get the board nice, than the former.

Mike.

 

[lurker]

you cant get more common that our practices! But it is a subject that needs to be in peoples minds when giving advice.

Remember the famous case of the american camper van owner who engaged cruise control on his brand new van and then got out of the seat to make coffee. He won his court case after the crash because the instruction book didnt tell him he couldnt.
That makes us lot positively wild, doesnt it?

Except it never happened!
You really must stop reading the daily mail Bob yer daft old sod :lol: :lol:

 

[sunnybob]

ok, so its a scare story, but thats what its meant to do, scare you into thinking before giving advice to others.

Cant afford the mail now, my pension is so much smaller with the pound crash, i have to read the free classifieds.

 

[ComfortablyNumb]

If I went into work tomorrow, removed the riving knife and then ripped a piece of Iroko in 2 hits I'd get the sack. I don't let apprentices use a machine unsupervised until they're 18, have demonstrated a high level of competence and have used the machine supervised for at least a few weeks. I shudder when I read posts on here where people with zero experience are buying and using kit that can take your hand off or kill in a split second

 

[lurker]

Agree
The ts is a dangerous tool unless you have suitable awareness.

The problem is folks watch USA u tubes and don't know any better