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Cutting dadoes: How much better is an upcut spiral routing bit?

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Michael

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Sep 14, 2016, 12:01:49 PM9/14/16
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I need to cut some dadoes and I'm wondering if it's really worth the expense to buy an upcut spiral routing bit? Does it bring that much more joy over a standard router bit?

Thanks,

Mike

-MIKE-

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Sep 14, 2016, 12:56:19 PM9/14/16
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If it helps direct the chips to the dust collector port, it will bring a
lot of joy.
One of the biggest downsides to cutting dadoes with a straight router
bit is the fact that the chips can clog the path very easily, slowing
down the entire process.

You *really* want a joyful experience in cutting dadoes?
Get a dado set for your table saw. :-D


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-MIKE-

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woodchucker

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Sep 14, 2016, 1:44:08 PM9/14/16
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Not for dadoes.

Upcut is somewhat necessary for deep mortices though . it helps remove
the chips. the key word is somewhat, not totally necessary.

--
Jeff

Leon

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Sep 14, 2016, 3:17:13 PM9/14/16
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On 9/14/2016 11:56 AM, -MIKE- wrote:
> On 9/14/16 11:01 AM, Michael wrote:
>> I need to cut some dadoes and I'm wondering if it's really worth the
>> expense to buy an upcut spiral routing bit? Does it bring that much
>> more joy over a standard router bit?
>>
>> Thanks,
>>
>> Mike
>>
>
> If it helps direct the chips to the dust collector port, it will bring a
> lot of joy.
> One of the biggest downsides to cutting dadoes with a straight router
> bit is the fact that the chips can clog the path very easily, slowing
> down the entire process.
>



> You *really* want a joyful experience in cutting dadoes?
> Get a dado set for your table saw. :-D

+10

John Grossbohlin

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Sep 14, 2016, 4:12:45 PM9/14/16
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"Michael" wrote in message
news:23a92b59-7a4e-4e7d...@googlegroups.com...

>I need to cut some dadoes and I'm wondering if it's really worth the
>expense to buy an upcut spiral routing bit? Does it bring that much more
>joy over >a standard router bit?

I think there is an "it depends" that goes with this... I've run into cases
where an upcut bit caused splintering on the surface that didn't happen as
much with a straight bit.

However, it's been quite a while since I've used a router for mortises (I
got a hollow chisel mortiser) so I don't recall the details of what bit,
what kind of wood, etc.

You may have to play a bit... ;~)

Electric Comet

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Sep 14, 2016, 7:29:00 PM9/14/16
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On Wed, 14 Sep 2016 09:01:47 -0700 (PDT)
Michael <michael...@gmail.com> wrote:

> I need to cut some dadoes and I'm wondering if it's really worth the
> expense to buy an upcut spiral routing bit? Does it bring that much

why are you considering it

what info led you to think it would be better

testing your dados is the best thing to do and if the bit you have is
not doing waht you want then











J. Clarke

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Sep 14, 2016, 7:50:51 PM9/14/16
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In article <mo-dnS1eydGoMkTK...@earthlink.com>,
nospam....@nospam.earthlink.net says...
The main benefit of the spiral bit is that it clears the shavings more
efficiently than a straight bit. There are some downsides. The first
one is make _sure_ that the collet and bit are absolutely clean (I work
it over with a pistol cleaning rod and lacquer thinner) otherwise no
matter how tight you think it is the bit may start pulling out. If
you're using one in a table do _not_ trust the thickness of the stock to
protect you--I had one work out a full inch in a single cut once and pop
through the surface right where my hand had been a second earlier.
Another is that they're amazingly fragile--if you're using one in a
table be sure that the stock is completely controlled. And the ones I
have used (Amana, Freud, Whiteside) all cut just a hair undersized.

John McCoy

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Sep 15, 2016, 11:53:30 AM9/15/16
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Michael <michael...@gmail.com> wrote in
news:23a92b59-7a4e-4e7d...@googlegroups.com:

> I need to cut some dadoes and I'm wondering if it's really worth the
> expense to buy an upcut spiral routing bit? Does it bring that much
> more joy over a standard router bit?

As woodchucker said, generally not for dados. The real
question is whether you're cutting a stopped or open cut.
If it's open (like most dados) there's an exit path for
the chips. If it's stopped (like, in the extreme case,
a mortise) the chips will get trapped in the cut unless
they are lifted out, which is what an upcut bit does.

If you're cutting stopped cuts with a straight bit, you
just need to make shallower cuts and dump the chips out
(or vaccuum them out) after each cut. A spiral bit will
let you work faster in that case.

John

DerbyDad03

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Sep 15, 2016, 1:33:40 PM9/15/16
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I'll voice a novice opinion and say that that depends on the jig
being used for the stopped cuts.

I recently used a jig to cut the mortises for some bed rail hardware.
The jig was based on swingman's design as shown here:

http://www.e-woodshop.net/images/MortJig2.JPG

The problem wasn't the chips in the mortise as much as it was the chips
that piled up against the stop rails at each end. Those are the ones that
I had to keep vacuuming out so that the router could travel the full
distance.

I used a straight bit but I don't think that an upcut bit would have
helped. The chips had no problem getting out of the shallow mortise
with the straight bit, it was the piling up at the stops that was the
issue.

I've seen other jigs made with stops that were flush with the surface
that the router sat on. If that type of jig were used, then the difference
between a straight bit and upcut bit - especially for deep mortises -
would be really evident.

Michael

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Sep 18, 2016, 4:30:38 PM9/18/16
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On Thursday, September 15, 2016 at 12:33:40 PM UTC-5, DerbyDad03 wrote:
> On Thursday, September 15, 2016 at 11:53:30 AM UTC-4, John McCoy wrote:


Thanks everyone for the great information. These are not through dadoes, so a dado stack will not work. I once saw Glen Huey using an upcut spiral bit on a woodworking show to cut dadoes for a spice rack. I wasn't sure why he used that bit, but from I read here it appears it does the job for clearing chips. I'm going to try to cut my dadoes with my regular routing bit first to see how it goes.

Mike

Leon

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Sep 18, 2016, 4:35:32 PM9/18/16
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Just a FYI, I do not believe that there is any such thing as a "through"
dado, that would result in two pieces of material.
Perhaps you are wanting a "stopped" dado, one that does not go all the
way across the material.

You can do stopped dado's with a stacked dado set but that does require
planing and is not always possible.

woodchucker

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Sep 18, 2016, 11:30:23 PM9/18/16
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BTW, Glen Huey is not the guy to gleem info from. He's dangerous.
There are more competent and talented people out there.

--
Jeff

John McCoy

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Sep 19, 2016, 10:38:10 AM9/19/16
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Leon <lcb11211@swbelldotnet> wrote in
news:IoWdnZ1vof4TZ0PK...@giganews.com:

> Just a FYI, I do not believe that there is any such thing as a
> "through" dado, that would result in two pieces of material.

Hmmm, pretty sure I've seen writers use "through" as the
opposite to "stopped". I'm not sure what other word you'd
use to describe a dado that went from one side to the other
of the workpiece.

I'll note that a dado could be stopped on one end or both
ends, altho the latter would usually be called a mortise
(even if it's long and shallow).

Stopped (at one end) dados with a stacked dado set on the
tablesaw would require cleanup with a chisel (or a weird
shape on the end of whatever went in the dado). I wouldn't
do it that way because I use a sled, and it would be difficult
to mark the stopping point.

John

Swingman

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Sep 19, 2016, 11:26:25 AM9/19/16
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On 9/19/2016 9:38 AM, John McCoy wrote:

> Hmmm, pretty sure I've seen writers use "through" as the
> opposite to "stopped".

I've also seen "blind", in place of "stopped" ("stopped" was commonly
used in the UK when I worked there), mentioned when describing dadoes.

In the UK they were also known as "housing" joints (cut across the
grain), with many different types, including:

Through housing joint
Dovetail housing joint
Stopped housing joint
Stopped straight dovetail housing joint
Tapered stopped housing joint
Barefaced housing joint (AKA "locking rabbet" joint in the US)

... and probably some more.

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Leon

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Sep 19, 2016, 3:29:24 PM9/19/16
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On 9/19/2016 9:38 AM, John McCoy wrote:
> Leon <lcb11211@swbelldotnet> wrote in
> news:IoWdnZ1vof4TZ0PK...@giganews.com:
>
>> Just a FYI, I do not believe that there is any such thing as a
>> "through" dado, that would result in two pieces of material.
>
> Hmmm, pretty sure I've seen writers use "through" as the
> opposite to "stopped". I'm not sure what other word you'd
> use to describe a dado that went from one side to the other
> of the workpiece.

IMHO through means all the way through. If you cut a through dado on a
board you have two pieces left over. Think through mortise
The OP said these were not through dado's so a stacked dado would not work.


>
> I'll note that a dado could be stopped on one end or both
> ends, altho the latter would usually be called a mortise
> (even if it's long and shallow).
>
> Stopped (at one end) dados with a stacked dado set on the
> tablesaw would require cleanup with a chisel (or a weird
> shape on the end of whatever went in the dado). I wouldn't
> do it that way because I use a sled, and it would be difficult
> to mark the stopping point.

Shelves are typically embedded into stopped dado's The stop is near the
front of the cabinet and a notch is cut out of the front ends of the
shelf back from the front of the shelf about the length of the part of
the dado that is not full depth.

John McCoy

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Sep 19, 2016, 3:52:11 PM9/19/16
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Leon <lcb11211@swbelldotnet> wrote in
news:uLOdnUO15aYWoX3K...@giganews.com:

> On 9/19/2016 9:38 AM, John McCoy wrote:
>> Leon <lcb11211@swbelldotnet> wrote in
>> news:IoWdnZ1vof4TZ0PK...@giganews.com:
>>
>>> Just a FYI, I do not believe that there is any such thing as a
>>> "through" dado, that would result in two pieces of material.
>>
>> Hmmm, pretty sure I've seen writers use "through" as the
>> opposite to "stopped". I'm not sure what other word you'd
>> use to describe a dado that went from one side to the other
>> of the workpiece.
>
> IMHO through means all the way through.

Well it is all the way through. It's all the way through
from the left side to the right side.

> Shelves are typically embedded into stopped dado's The stop is near
> the front of the cabinet and a notch is cut out of the front ends of
> the shelf back from the front of the shelf about the length of the
> part of the dado that is not full depth.

Exactly. So you either have a notch in the shelf that's
longer than it needs to be (which may or may not be visible)
or you square up the end of the dado with a chisel (which
is probably what I'd do).

John

Leon

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Sep 19, 2016, 5:15:31 PM9/19/16
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On 9/19/2016 2:52 PM, John McCoy wrote:
> Leon <lcb11211@swbelldotnet> wrote in
> news:uLOdnUO15aYWoX3K...@giganews.com:
>
>> On 9/19/2016 9:38 AM, John McCoy wrote:
>>> Leon <lcb11211@swbelldotnet> wrote in
>>> news:IoWdnZ1vof4TZ0PK...@giganews.com:
>>>
>>>> Just a FYI, I do not believe that there is any such thing as a
>>>> "through" dado, that would result in two pieces of material.
>>>
>>> Hmmm, pretty sure I've seen writers use "through" as the
>>> opposite to "stopped". I'm not sure what other word you'd
>>> use to describe a dado that went from one side to the other
>>> of the workpiece.
>>
>> IMHO through means all the way through.

So by that thought process a through mortise would be a dado or grove
all the way a cross a board.




Leon

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Sep 19, 2016, 5:20:26 PM9/19/16
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Michael

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Sep 19, 2016, 8:12:59 PM9/19/16
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Apologies absolutely not necessary.
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