As a newbie I have read with interest the various posts on the dangers
of bevel saw cuts and have concluded that the possiblity of kick back
occurs when, for example, a right tilt arbor is used from the right
side (i.e the larger piece of wood and the fence/mitre are all on the
right) so that the small waste piece falls to the left and jams in the
blade. Is this a correct interpretation ?
I have a right-tilt Delta cabinet saw with a unisaw fence and
extension table on the right, I work always on the right side of the
blade.
Now here's my question. I want to build some cabinets that will a
45% bevel through 1" thick MDF -- I will therefore need to run the
short end of a 17" by 48" through the saw. I can't do this cut from
the left as I don't have any extension table on that side and it's
too close to the wall of my workshop. I am hesitant, however, to
run it through from the right on a right-tilt arbor. Given that that
the danger only appears to be when small bits fall into the blade,
would I be OK to work from the right side provided I allowed for a
reasonable amount of waste on the left ? (say three or four inches).
Or, is there some other inherent danger that I missed.
Thanks for any information
Jenny
On Mon, 2 Feb 2004 22:16:19 -0800, Jenny Steel wrote
(in message <[email protected]>):
> As a newbie I have read with interest the various posts on the dangers
> of bevel saw cuts and have concluded that the possiblity of kick back
> occurs when, for example, a right tilt arbor is used from the right
> side (i.e the larger piece of wood and the fence/mitre are all on the
> right) so that the small waste piece falls to the left and jams in the
> blade. Is this a correct interpretation ?
>
I don't think so. My interpretation is that the danger lies in the piece to
the right of the blade, ie. the piece *beneath* the blade, will become jammed
between the blade and the fence if the work twists at all.
Got a router table with a good fence? With a 45 degree
chamfer bit you can savely bevel edges if you've got the
bit and the fence set up correctly. You will need feather
boards to keep the stock firmly against the fence if you
want nice clean edges.
If you want to get tricky you can go with a lock miter
bit (see thread in a.b.p.w.)
Not as fast as on the table saw but a hell of a lot safer.
BTW - MDF will dull saw blade teeth AND router bits a lot
faster than most woods will.
charlie b
Thankyou all for your interesting comments.
Firstly I'd like to clarify that I had not intended to use a fence for
this operation (thankyou Mr M for your words of wisdom) ... although
a newbie I do realize that to cut the short end of a 17" by 48" using
the fence presents all kinds of dangers.
I have a heavy-duty extending mitre gauge (with a clampdown attached)
that I had assumed would give sufficient support for the considerable
weight of the MDF -- would a cut-off sled be better ?
Unfortunately Mr Bridger, flipping the stock over and cutting from the
"safe" side is an option only if I completely reverse my table saw
set-up. As Mr Upscale notes all my support is on the right side and
I'd prefer to leave my current set-up intact if I can.
I've never seen a "cut-off sled" as suggested by Mr Pagona so yes Mr
Geedubb I would really like to see your pictures and receive any words
of wisdom on its construction techniques.
While I think I understand Mr Jacobson's technique to avoid "trapped
arrows" I'm not sure that I understand why this technique would in
fact prevent a trapped arrow or how I could apply this technique to my
particular problem -- the technique seems applicable for small pieces
or when working from the left side. Certainly a further explanation
of the technique and why it presents more safety would be useful.
So to return to my particular problem of how to cut a bevel thorouh a
17" by 48" piece of 1" MDF using a right tilt arbor on a right cut-off
table set-up....will the following, in all your opinions, be safe ?
1) I use my miter guage(or a sled) and not the fence to prevent the
blade/fence twist problem and, 2) I allow for three to four inches on
the waste side to prevent the "ejection" or "trapped arrow" problem.
respectfully
Jenny Steel (newbie)
charlie b <[email protected]> wrote in message news:<[email protected]>...
> Got a router table with a good fence? With a 45 degree
> chamfer bit you can savely bevel edges if you've got the
> bit and the fence set up correctly. You will need feather
> boards to keep the stock firmly against the fence if you
> want nice clean edges.
>
> If you want to get tricky you can go with a lock miter
> bit (see thread in a.b.p.w.)
>
> Not as fast as on the table saw but a hell of a lot safer.
>
> BTW - MDF will dull saw blade teeth AND router bits a lot
> faster than most woods will.
>
> charlie b
Charlie,
Yes I do have a router table but unfortunately not one with a big
enough cut-off table to handle my 17" by 48" piece of MDF, nor am I
sure that I can acquire a chamfer bit that would cut a 45% mitre in a
1" piece of MDF. I'll look into this technique more.... perhaps I
could rig something up with the router table.
Thanks for the suggestion
<<snip>>
> Now here's my question. I want to build some cabinets that will a
> 45% bevel through 1" thick MDF -- I will therefore need to run the
> short end of a 17" by 48" through the saw.
<<Snip>>
To cut the SHORT side of that pannel, you do NOT want the fence anywhere in
that operation. Even without a bevel, that is an invitation to kickback.
This is why people build sleds (a.k.a. pannel cutting jigs).
When using a rip fence, the *long* edge of your stock should ride against
the fence, otherwise there is not enough support to counter any possible
twist in the orientation of the workpiece. Twist, brings the workpiece into
contact with the trailing edge of the blade; contact with the trailing edge
of the blade is what will fling wood at you. Kickback!
Be safe,
Steve
> ........... on the dangers of bevel saw cuts and have concluded that the
possiblity of kick back occurs ....
Kelly Mehler, the table saw maven, describes "kickback" as the situation
when the blade grabs the work and pulls it back through an arc leaving a
gouge and possibly injuring the operator's hand. The situation where a piece
of cut off stock which is trapped between the blade and the fence and shoots
back as "ejection". This was called a "trapped arrow", and is really grim to
be hit by one.
> ....... I want to build some cabinets that will a 45% bevel through 1"
thick MDF -- I will therefore need to run the short end of a 17" by 48"
through the saw.
I was taught an excellent beveling technique for a right-tilting blade:
1) Attach a sacrificial fence to the regular fence.
2) Set the fence distance from the blade to the thickness of the stock
3) Tilt the blade to 45 degrees
4) Turn on the saw and raise the blade into the sacrificial fence.
5) Pass a sample along the fence
6) If you have a sharp bevel, it's okay. If not, stop the saw -- retract
the blade --- adjust the fence- to-blade distance properly --- raise the
blade and make a test cuts until the bevel is okay.
IMPORTANT:To avoid getting a prism shaped trapped arrow, I make small
chamfer with a router along the edges that I'll bevel. This leaves a thin
piece under the blade that presents no danger.
This may sound laborious, But it isn't, and I get perfect beveled edges
safely.
Joel
> Joel, what did you mean in statement #6 by "okay"?
I wrote:
6) If you have a sharp bevel, it's okay. If not, stop the saw -- retract
the blade --- adjust the fence- to-blade distance properly --- raise the
blade and make a test cuts until the bevel is okay.
I mean that your bevel's edge should come to a sharp, crisp line. If you set
the fence at the improper distance, you'll have a flat rather than a shard
edge.
I hope this is clear.
By the way, I've used this technique to make several display stands for
sculpture and folk art. The display folks at the National Gallery of Art
told me about this.
Make an outer box the proper size from MDO by beveling the vertical edges
and the top edges and the top. Leave the bottom flat. They staple the
bevels together and fill and paint the box. Then make a box that will fit
snugly inside the display box, and place weights in that. They use elevator
weights --- I use lead ingots. Slip the outer box over that and place the
object on that pedestal.
I'm considering creating a web page to show this technique, is it worth the
effort?
Joel
Three pictures posted on abpw.
Gary
Jenny Steel wrote:
> Thankyou all for your interesting comments.
>
> Firstly I'd like to clarify that I had not intended to use a fence for
> this operation (thankyou Mr M for your words of wisdom) ... although
> a newbie I do realize that to cut the short end of a 17" by 48" using
> the fence presents all kinds of dangers.
>
> I have a heavy-duty extending mitre gauge (with a clampdown attached)
> that I had assumed would give sufficient support for the considerable
> weight of the MDF -- would a cut-off sled be better ?
>
> Unfortunately Mr Bridger, flipping the stock over and cutting from the
> "safe" side is an option only if I completely reverse my table saw
> set-up. As Mr Upscale notes all my support is on the right side and
> I'd prefer to leave my current set-up intact if I can.
>
> I've never seen a "cut-off sled" as suggested by Mr Pagona so yes Mr
> Geedubb I would really like to see your pictures and receive any words
> of wisdom on its construction techniques.
>
> While I think I understand Mr Jacobson's technique to avoid "trapped
> arrows" I'm not sure that I understand why this technique would in
> fact prevent a trapped arrow or how I could apply this technique to my
> particular problem -- the technique seems applicable for small pieces
> or when working from the left side. Certainly a further explanation
> of the technique and why it presents more safety would be useful.
>
> So to return to my particular problem of how to cut a bevel thorouh a
> 17" by 48" piece of 1" MDF using a right tilt arbor on a right cut-off
> table set-up....will the following, in all your opinions, be safe ?
>
> 1) I use my miter guage(or a sled) and not the fence to prevent the
> blade/fence twist problem and, 2) I allow for three to four inches on
> the waste side to prevent the "ejection" or "trapped arrow" problem.
>
> respectfully
>
> Jenny Steel (newbie)
"Jenny Steel" <[email protected]> wrote in message
news:[email protected]...
> Thankyou all for your interesting comments.
>
> Firstly I'd like to clarify that I had not intended to use a fence for
> this operation (thankyou Mr M for your words of wisdom) ... although
> a newbie I do realize that to cut the short end of a 17" by 48" using
> the fence presents all kinds of dangers.
>
> I have a heavy-duty extending mitre gauge (with a clampdown attached)
> that I had assumed would give sufficient support for the considerable
> weight of the MDF -- would a cut-off sled be better ?
IMHO, yes. With a sled, all of the friction is between the sled and the
table, with a miter gauge, there is more "contact" between the work-piece
and the table than the workpiece and the fence. This drag can cause the
workpiece to shift in relation to the fence. This won't happen with a sled.
Also The fence on a sled is generally longer. It is also more stable because
its squareness to the miter slot is triangulated by the base of the sled.
> I've never seen a "cut-off sled" as suggested by Mr Pagona so yes Mr
> Geedubb I would really like to see your pictures and receive any words
> of wisdom on its construction techniques
GEEDUBB's posting on ABPW is a fine example.
>
> 1) I use my miter guage(or a sled) and not the fence to prevent the
> blade/fence twist problem and, 2) I allow for three to four inches on
> the waste side to prevent the "ejection" or "trapped arrow" problem.
All you need is a 1/4" more than your waste piece.... but just move the rip
fence out of there.
-s
This is correct. I speak from experience. I did this very cut a couple
months ago on a piece of 5/4 stock. The piece between the blade and fence
(on a right tilt) came FLYING out, hit me square in the left hip, ripped a 4
inch slash in my jeans (heavy denim), and left a nasty bruise and scrape on
my hip. It actually didn't hurt much, but it scared the poop out of me.
I won't do that again. Fortunately, I have 66" rails on my Incra fence.
All I should have done (but will in the future) is flip the fence over to
the left side of the blade and then do the cut.
Bob
"Paul Hays" <[email protected]> wrote in message
news:[email protected]...
> On Mon, 2 Feb 2004 22:16:19 -0800, Jenny Steel wrote
> (in message <[email protected]>):
>
> > As a newbie I have read with interest the various posts on the dangers
> > of bevel saw cuts and have concluded that the possiblity of kick back
> > occurs when, for example, a right tilt arbor is used from the right
> > side (i.e the larger piece of wood and the fence/mitre are all on the
> > right) so that the small waste piece falls to the left and jams in the
> > blade. Is this a correct interpretation ?
> >
> I don't think so. My interpretation is that the danger lies in the piece
to
> the right of the blade, ie. the piece *beneath* the blade, will become
jammed
> between the blade and the fence if the work twists at all.
>
>
>
>
>
Joel, what did you mean in statement #6 by "okay"? I didn't follow.
"Joel Jacobson" <[email protected]> wrote in message
news:[email protected]...
> I was taught an excellent beveling technique for a right-tilting blade:
>
> 1) Attach a sacrificial fence to the regular fence.
> 2) Set the fence distance from the blade to the thickness of the stock
> 3) Tilt the blade to 45 degrees
> 4) Turn on the saw and raise the blade into the sacrificial fence.
> 5) Pass a sample along the fence
> 6) If you have a sharp bevel, it's okay. If not, stop the saw -- retract
> the blade --- adjust the fence- to-blade distance properly --- raise the
> blade and make a test cuts until the bevel is okay.
On 2 Feb 2004 22:16:19 -0800, [email protected] (Jenny Steel)
wrote:
>As a newbie I have read with interest the various posts on the dangers
>of bevel saw cuts and have concluded that the possiblity of kick back
>occurs when, for example, a right tilt arbor is used from the right
>side (i.e the larger piece of wood and the fence/mitre are all on the
>right) so that the small waste piece falls to the left and jams in the
>blade. Is this a correct interpretation ?
>
>I have a right-tilt Delta cabinet saw with a unisaw fence and
>extension table on the right, I work always on the right side of the
>blade.
>
>Now here's my question. I want to build some cabinets that will a
>45% bevel through 1" thick MDF -- I will therefore need to run the
>short end of a 17" by 48" through the saw. I can't do this cut from
>the left as I don't have any extension table on that side and it's
>too close to the wall of my workshop. I am hesitant, however, to
>run it through from the right on a right-tilt arbor. Given that that
>the danger only appears to be when small bits fall into the blade,
>would I be OK to work from the right side provided I allowed for a
>reasonable amount of waste on the left ? (say three or four inches).
>
>Or, is there some other inherent danger that I missed.
>
>Thanks for any information
>
>Jenny
flip the stock over and make the bevel cut from the safe side of the
saw.
"Bridger" <[email protected]> wrote in message
news:[email protected]...
> flip the stock over and make the bevel cut from the safe side of the
> saw.
That's ok if the piece is not too wide, but for sheets of wood of any size,
you run into support problems for what hangs over the left edge of the saw
table top. Extensions and wings are there for a purpose.
You could make a large cut off sled, specifically for beveling at a 45° angle.
The sled, which should extend to both sides of the blade and have a runner in
each miter slot, would make the cut safer by:
-not having a fence, so the board couldn't get pinched between the fence and
the blade.
-support the off cut.
-allow you to clamp the board to the sled if you feel you need the extra
precaution.
Cross cutting a 17" x 48" piece by running the 17" side against the fence is
asking for a kickback, even if the blade is vertical. A sled, sliding table or
an extended miter gauge is pretty much a necessity.
David
remove the key to email me.
Get a set of small ball bering casters and put them in the miter slot along
with the runners. This would lift the sled and make pushing it much easier.
> You could make a large cut off sled, specifically for beveling at a 45°
angle.
> The sled, which should extend to both sides of the blade and have a runner
in
> each miter slot, would make the cut safer by:
> -not having a fence, so the board couldn't get pinched between the fence
and
> the blade.
> -support the off cut.
> -allow you to clamp the board to the sled if you feel you need the extra
> precaution.
J Pagona aka Y.B. wrote:
> You could make a large cut off sled, specifically for beveling at a
> 45° angle. The sled, which should extend to both sides of the blade
> and have a runner in each miter slot, would make the cut safer by:
> -not having a fence, so the board couldn't get pinched between the
> fence and the blade.
> -support the off cut.
> -allow you to clamp the board to the sled if you feel you need the
> extra precaution.
>
> Cross cutting a 17" x 48" piece by running the 17" side against the
> fence is asking for a kickback, even if the blade is vertical. A
> sled, sliding table or an extended miter gauge is pretty much a
> necessity.
>
> David
>
> remove the key to email me.
That's what I did recently. I can post pictures if anybody wants.
Gary
Thanks for patient reply. I get it now.
Bob
"Joel Jacobson" <[email protected]> wrote in message
news:[email protected]...
>
> > Joel, what did you mean in statement #6 by "okay"?
>
> I wrote:
>
> 6) If you have a sharp bevel, it's okay. If not, stop the saw -- retract
> the blade --- adjust the fence- to-blade distance properly --- raise the
> blade and make a test cuts until the bevel is okay.
>
> I mean that your bevel's edge should come to a sharp, crisp line. If you
set
> the fence at the improper distance, you'll have a flat rather than a shard
> edge.
>
> I hope this is clear.
>
> By the way, I've used this technique to make several display stands for
> sculpture and folk art. The display folks at the National Gallery of Art
> told me about this.
>
> Make an outer box the proper size from MDO by beveling the vertical edges
> and the top edges and the top. Leave the bottom flat. They staple the
> bevels together and fill and paint the box. Then make a box that will fit
> snugly inside the display box, and place weights in that. They use
elevator
> weights --- I use lead ingots. Slip the outer box over that and place the
> object on that pedestal.
>
> I'm considering creating a web page to show this technique, is it worth
the
> effort?
>
> Joel
>
>