I have a reasonable number of notches to be cut into 100 x 47 timbers

Want to cut cross slots 30mm deep so timbers will slot over some 200 x
47 beams, good enough for glue joints.

Want to do the job neatly, and I have 28 of them to do.


I notice that whenever they need to do this sort of thing on any of the
US shows (New Yankee Workshop for example) the use a Dado blade in a
bench saw.
I'm pretty sure you can't fit a Dado blade to most domestic saw benches
(I have a JCB model) only the large commercial machines.

What is the neatest & consistent way of doing these ........ I know I
could mark out, use saw table to make shoulder cuts and chisel out the
rest ... but this will be slow and probably not end up as neat as I want.


I do have a Router table with a Trend T7 ... but not sure if there is an
easy way to use that. Certainly don't have a 47mm wide bit, so it would
require moving wood and bit several times - possibly end up inaccurate.


Any tips & hints ?

On 01/09/13 23:08, Rick Hughes wrote:
I have a reasonable number of notches to be cut into 100 x 47 timbers

Want to cut cross slots 30mm deep so timbers will slot over some 200 x
47 beams, good enough for glue joints.

Want to do the job neatly, and I have 28 of them to do.


I notice that whenever they need to do this sort of thing on any of
the US shows (New Yankee Workshop for example) the use a Dado blade in
a bench saw.
I'm pretty sure you can't fit a Dado blade to most domestic saw
benches (I have a JCB model) only the large commercial machines.

What is the neatest & consistent way of doing these ........ I know I
could mark out, use saw table to make shoulder cuts and chisel out the
rest ... but this will be slow and probably not end up as neat as I want.


I do have a Router table with a Trend T7 ... but not sure if there is
an easy way to use that. Certainly don't have a 47mm wide bit, so it
would require moving wood and bit several times - possibly end up
inaccurate.


Any tips & hints ?
you can jig rout this easily if you want accuracy.

just needs a bnig square hole for the jig and off you go

But really, for lumber? two saw cuts with a hand saw and knock out the
middle.

--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to lead are elected by the least capable of producing, and where the members of society least likely to sustain themselves or succeed, are rewarded with goods and services paid for by the confiscated wealth of a diminishing number of producers.

On Sun, 01 Sep 2013 23:20:47 +0100, The Natural Philosopher wrote:

But really, for lumber? two saw cuts with a hand saw and knock out the
middle.

That was my thought as well, why do you need a power tool at all?
Sharp crosscut handsaw just inside the line to a couple of mm above
the required depth. Knock out the block or take it out with thick
chisel cuts and then chisel the base and bottom corners neatly.

Does require the skills to use a handsaw, mallet and chisel
accurately though...

--
Cheers
Dave.

On Monday, September 2, 2013 10:20:47 AM UTC+12, The Natural Philosopher wrote:

But really, for lumber? two saw cuts with a hand saw and knock out the

middle.

I'd use a Skilsaw for the two cuts and knock out the middle.
I have become expert at running the Skilsaw sideways to make the bottom extremely neat.

"Rick Hughes" wrote in message
...
I have a reasonable number of notches to be cut into 100 x 47 timbers

Want to cut cross slots 30mm deep so timbers will slot over some 200 x 47
beams, good enough for glue joints.

Want to do the job neatly, and I have 28 of them to do.


I notice that whenever they need to do this sort of thing on any of the US
shows (New Yankee Workshop for example) the use a Dado blade in a bench
saw.
I'm pretty sure you can't fit a Dado blade to most domestic saw benches (I
have a JCB model) only the large commercial machines.

What is the neatest & consistent way of doing these ........ I know I
could mark out, use saw table to make shoulder cuts and chisel out the
rest ... but this will be slow and probably not end up as neat as I want.


I do have a Router table with a Trend T7 ... but not sure if there is an
easy way to use that. Certainly don't have a 47mm wide bit, so it would
require moving wood and bit several times - possibly end up inaccurate.


Any tips & hints ?

This is a poor method of jointing and not to be be recommended for strucural
work as it significantly weakens the whole job.

If this is for house construction the usual method is to use metal
joints/connectors which are nailed and far far stronger.

http://www.strongtie.co.uk/products/family_timber.php

On 02/09/2013 06:16, harryagain wrote:
"Rick Hughes" wrote in message
...
I have a reasonable number of notches to be cut into 100 x 47 timbers

Want to cut cross slots 30mm deep so timbers will slot over some 200 x 47
beams, good enough for glue joints.

Want to do the job neatly, and I have 28 of them to do.


I notice that whenever they need to do this sort of thing on any of the US
shows (New Yankee Workshop for example) the use a Dado blade in a bench
saw.
I'm pretty sure you can't fit a Dado blade to most domestic saw benches (I
have a JCB model) only the large commercial machines.

What is the neatest & consistent way of doing these ........ I know I
could mark out, use saw table to make shoulder cuts and chisel out the
rest ... but this will be slow and probably not end up as neat as I want.


I do have a Router table with a Trend T7 ... but not sure if there is an
easy way to use that. Certainly don't have a 47mm wide bit, so it would
require moving wood and bit several times - possibly end up inaccurate.


Any tips & hints ?

This is a poor method of jointing and not to be be recommended for strucural
work as it significantly weakens the whole job.

Bollox. Utter bollox.


--
Dave - The Medway Handyman www.medwayhandyman.co.uk

On 01/09/2013 23:08, Rick Hughes wrote:
I have a reasonable number of notches to be cut into 100 x 47 timbers

Want to cut cross slots 30mm deep so timbers will slot over some 200 x
47 beams, good enough for glue joints.

Want to do the job neatly, and I have 28 of them to do.


I notice that whenever they need to do this sort of thing on any of the
US shows (New Yankee Workshop for example) the use a Dado blade in a
bench saw.
I'm pretty sure you can't fit a Dado blade to most domestic saw benches
(I have a JCB model) only the large commercial machines.

Dado blades aren't allowed in the UK because of Effin Softy.

What is the neatest & consistent way of doing these ........ I know I
could mark out, use saw table to make shoulder cuts and chisel out the
rest ... but this will be slow and probably not end up as neat as I want.


I do have a Router table with a Trend T7 ... but not sure if there is an
easy way to use that. Certainly don't have a 47mm wide bit, so it would
require moving wood and bit several times - possibly end up inaccurate.


Any tips & hints ?

I do this all the time, notching newel posts for decking.

Circular saw set to the depth you want. Use a rafter square, home made
jig or one of these;

http://www.amazon.co.uk/Kreg-305mm-1...&keywords=kreg

to ensure a square cut. Cut each side accurately, then make a series of
free hand cuts a few mm apart (working right to left, so the base of the
saw is supported).

Knock out the waste & trim with a sharp chisel.

Fast & accurate.

--
Dave - The Medway Handyman www.medwayhandyman.co.uk

On 02/09/2013 08:43, The Medway Handyman wrote:
On 01/09/2013 23:08, Rick Hughes wrote:
I have a reasonable number of notches to be cut into 100 x 47 timbers

Want to cut cross slots 30mm deep so timbers will slot over some 200 x
47 beams, good enough for glue joints.

Want to do the job neatly, and I have 28 of them to do.


I notice that whenever they need to do this sort of thing on any of the
US shows (New Yankee Workshop for example) the use a Dado blade in a
bench saw.
I'm pretty sure you can't fit a Dado blade to most domestic saw benches
(I have a JCB model) only the large commercial machines.

Dado blades aren't allowed in the UK because of Effin Softy.

What is the neatest & consistent way of doing these ........ I know I
could mark out, use saw table to make shoulder cuts and chisel out the
rest ... but this will be slow and probably not end up as neat as I want.


I do have a Router table with a Trend T7 ... but not sure if there is an
easy way to use that. Certainly don't have a 47mm wide bit, so it would
require moving wood and bit several times - possibly end up inaccurate.


Any tips & hints ?

I do this all the time, notching newel posts for decking.

Circular saw set to the depth you want. Use a rafter square, home made
jig or one of these;

http://www.amazon.co.uk/Kreg-305mm-1...&keywords=kreg


to ensure a square cut. Cut each side accurately, then make a series of
free hand cuts a few mm apart (working right to left, so the base of the
saw is supported).

Knock out the waste & trim with a sharp chisel.

Fast & accurate.

+1
but Harry may have a point

On Mon, 2 Sep 2013 06:16:44 +0100, harryagain wrote:

If this is for house construction the usual method is to use metal
joints/connectors which are nailed and far far stronger.

Only because any monkey can wield a hammer but it takes time and a
bit of skill to cut, accurate, tight fitting notches. I'd be inclined
to notch both bits of timber half the required depth than notch just
one the full depth though.

--
Cheers
Dave.

This is a poor method of jointing and not to be be recommended for strucural
work as it significantly weakens the whole job.

Bollox. Utter bollox.

Yes and no. In the OP's application he may be looking to raise a floor level, and structural strength of the new timbers is not important.

However timbers with a strength rating (C16, C24) can't be be cut down and the rating automatically maintained.

E.g. If you cut a 50*200mm C16 rated beam, you can't get 2 beams of 50*100mm rated at C16.

You *may* do, or it may be that the structural strength was concentrated in one side and the other has a significant defect within the timber.

(there's also a formula for de-rating for notches)

On 01/09/2013 23:20, The Natural Philosopher wrote:


But really, for lumber? two saw cuts with a hand saw and knock out the
middle.


Appreciate that, and that is the way I have done it in past
It's a finished joint on show .. and a lot of them

On 01/09/2013 23:49, Dave Liquorice wrote:
On Sun, 01 Sep 2013 23:20:47 +0100, The Natural Philosopher wrote:

But really, for lumber? two saw cuts with a hand saw and knock out the
middle.

That was my thought as well, why do you need a power tool at all?
Sharp crosscut handsaw just inside the line to a couple of mm above
the required depth. Knock out the block or take it out with thick
chisel cuts and then chisel the base and bottom corners neatly.

Does require the skills to use a handsaw, mallet and chisel
accurately though...



The only problem is ,,, in practise if grain is running at angle, you
can end up with notch breaking out, and ends up less than square ... but
don't dispute this is the trad way.

Just asked Q as on all the DIY programmes they show Dado saws being used
for this

On 02/09/2013 04:03, John Rumm wrote:
On 01/09/2013 23:08, Rick Hughes wrote:
I have a reasonable number of notches to be cut into 100 x 47 timbers

Want to cut cross slots 30mm deep so timbers will slot over some 200 x
47 beams, good enough for glue joints.

Want to do the job neatly, and I have 28 of them to do.

Watch this from about 1:50 on...

http://www.youtube.com/watch?v=DtizUSUgUG4

Thanks for link ... don't think I would hit out with hammer though

On 02/09/2013 06:16, harryagain wrote:

This is a poor method of jointing and not to be be recommended for strucural
work as it significantly weakens the whole job.

If this is for house construction the usual method is to use metal
joints/connectors which are nailed and far far stronger.

http://www.strongtie.co.uk/products/family_timber.php



This is not for house construction, and it is decorative so having any
steel ties is not an option.

Your points on construction are correct.

On 02/09/2013 08:43, The Medway Handyman wrote:


http://www.amazon.co.uk/Kreg-305mm-1...&keywords=kreg


to ensure a square cut. Cut each side accurately, then make a series of
free hand cuts a few mm apart (working right to left, so the base of the
saw is supported).

Knock out the waste & trim with a sharp chisel.

Fast & accurate.



Good link ... just treated myself to one of those .... Thnx

On 02/09/2013 10:11, Huge wrote:
On 2013-09-02, The Medway Handyman wrote:
On 01/09/2013 23:08, Rick Hughes wrote:
I have a reasonable number of notches to be cut into 100 x 47 timbers

Want to cut cross slots 30mm deep so timbers will slot over some 200 x
47 beams, good enough for glue joints.

Want to do the job neatly, and I have 28 of them to do.


I notice that whenever they need to do this sort of thing on any of the
US shows (New Yankee Workshop for example) the use a Dado blade in a
bench saw.
I'm pretty sure you can't fit a Dado blade to most domestic saw benches
(I have a JCB model) only the large commercial machines.

Dado blades aren't allowed in the UK because of Effin Softy.

You're kidding, right? A google search yields dozens of UK sources.




I did a lot of searching on w/end on this .... Dado blades are not
something that can be attached to your average DIY saw table ... as
arbor length is not long enough.
Several DIY tables specifically state that a you must NOT fit a Dado blade.

They are available for Commercial (Wadkin etc.) table saws, but elfen
safely does come into this .... in a Commercial use, there is a required
maximum duration for blade to come to a stop after stop is pressed, and
fitting a Dado blade will normally cause saw to exceed this.

The way around is that they then have to fit a DC brake to ensure it
stops within required time.

On 02/09/2013 11:28, Rick Hughes wrote:


http://www.youtube.com/watch?v=DtizUSUgUG4

Thanks for link ... don't think I would hit out with hammer though


You have to love the speed nail-hammering at 3.16.

On Monday, 2 September 2013 11:37:45 UTC+1, Rick Hughes wrote:
On 02/09/2013 10:11, Huge wrote:

On 2013-09-02, The Medway Handyman wrote:

On 01/09/2013 23:08, Rick Hughes wrote:

I have a reasonable number of notches to be cut into 100 x 47 timbers



Want to cut cross slots 30mm deep so timbers will slot over some 200 x

47 beams, good enough for glue joints.



Want to do the job neatly, and I have 28 of them to do.





I notice that whenever they need to do this sort of thing on any of the

US shows (New Yankee Workshop for example) the use a Dado blade in a

bench saw.

I'm pretty sure you can't fit a Dado blade to most domestic saw benches

(I have a JCB model) only the large commercial machines.



Dado blades aren't allowed in the UK because of Effin Softy.



You're kidding, right? A google search yields dozens of UK sources.









I did a lot of searching on w/end on this .... Dado blades are not

something that can be attached to your average DIY saw table ... as

arbor length is not long enough.

Several DIY tables specifically state that a you must NOT fit a Dado blade.



They are available for Commercial (Wadkin etc.) table saws, but elfen

safely does come into this .... in a Commercial use, there is a required

maximum duration for blade to come to a stop after stop is pressed, and

fitting a Dado blade will normally cause saw to exceed this.



The way around is that they then have to fit a DC brake to ensure it

stops within required time.

Lots of older (large/pro) tale saws needed DC brakes fitting to them to meet regs, even without a dado set. Inverters can do all that now.

AIUI since the HSE banned the use of dadoes, they did it by specifying the max length of arbor on new table saws on sale - not by banning the sale of dadoes.

On 02/09/2013 09:48, stuart noble wrote:
On 02/09/2013 08:43, The Medway Handyman wrote:
On 01/09/2013 23:08, Rick Hughes wrote:
I have a reasonable number of notches to be cut into 100 x 47 timbers

Want to cut cross slots 30mm deep so timbers will slot over some 200 x
47 beams, good enough for glue joints.

Want to do the job neatly, and I have 28 of them to do.


I notice that whenever they need to do this sort of thing on any of the
US shows (New Yankee Workshop for example) the use a Dado blade in a
bench saw.
I'm pretty sure you can't fit a Dado blade to most domestic saw benches
(I have a JCB model) only the large commercial machines.

Dado blades aren't allowed in the UK because of Effin Softy.

What is the neatest & consistent way of doing these ........ I know I
could mark out, use saw table to make shoulder cuts and chisel out the
rest ... but this will be slow and probably not end up as neat as I
want.


I do have a Router table with a Trend T7 ... but not sure if there is an
easy way to use that. Certainly don't have a 47mm wide bit, so it would
require moving wood and bit several times - possibly end up inaccurate.


Any tips & hints ?

I do this all the time, notching newel posts for decking.

Circular saw set to the depth you want. Use a rafter square, home made
jig or one of these;

http://www.amazon.co.uk/Kreg-305mm-1...&keywords=kreg



to ensure a square cut. Cut each side accurately, then make a series of
free hand cuts a few mm apart (working right to left, so the base of the
saw is supported).

Knock out the waste & trim with a sharp chisel.

Fast & accurate.

+1
but Harry may have a point

You need to consider how the thing is loaded and what you are nothing.
If you notch the top of a joist, and then fill it with a tight fitting
cross member, you will not lose much strength.

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 02/09/2013 08:43, The Medway Handyman wrote:
On 01/09/2013 23:08, Rick Hughes wrote:


Any tips & hints ?

I do this all the time, notching newel posts for decking.

Circular saw set to the depth you want. Use a rafter square, home made
jig or one of these;

http://www.amazon.co.uk/Kreg-305mm-1...&keywords=kreg


to ensure a square cut. Cut each side accurately, then make a series of
free hand cuts a few mm apart (working right to left, so the base of the
saw is supported).

Knock out the waste & trim with a sharp chisel.

Fast & accurate.


+1

On 02/09/2013 12:08, wrote:

AIUI since the HSE banned the use of dadoes, they did it by

Did they actually ban dado sets though? or just specify a maximum stop time?

specifying the max length of arbor on new table saws on sale - not by
banning the sale of dadoes.

Does not seem to be a problem on my 1948 Unisaw ;-)



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 02/09/2013 13:28, John Rumm wrote:
On 02/09/2013 12:08, wrote:

AIUI since the HSE banned the use of dadoes, they did it by

Did they actually ban dado sets though? or just specify a maximum stop
time?

specifying the max length of arbor on new table saws on sale - not by
banning the sale of dadoes.

Does not seem to be a problem on my 1948 Unisaw ;-)



Did admit to being tempted with the large number of Wadkin saws on ebay
... incl the tilting table versions

On 02/09/2013 11:37, Rick Hughes wrote:
On 02/09/2013 10:11, Huge wrote:
On 2013-09-02, The Medway Handyman wrote:
On 01/09/2013 23:08, Rick Hughes wrote:
I have a reasonable number of notches to be cut into 100 x 47 timbers

Want to cut cross slots 30mm deep so timbers will slot over some 200 x
47 beams, good enough for glue joints.

Want to do the job neatly, and I have 28 of them to do.


I notice that whenever they need to do this sort of thing on any of the
US shows (New Yankee Workshop for example) the use a Dado blade in a
bench saw.
I'm pretty sure you can't fit a Dado blade to most domestic saw benches
(I have a JCB model) only the large commercial machines.

Dado blades aren't allowed in the UK because of Effin Softy.

You're kidding, right? A google search yields dozens of UK sources.




I did a lot of searching on w/end on this .... Dado blades are not
something that can be attached to your average DIY saw table ... as
arbor length is not long enough.
Several DIY tables specifically state that a you must NOT fit a Dado blade.

They are available for Commercial (Wadkin etc.) table saws, but elfen
safely does come into this .... in a Commercial use, there is a required
maximum duration for blade to come to a stop after stop is pressed, and
fitting a Dado blade will normally cause saw to exceed this.

The way around is that they then have to fit a DC brake to ensure it
stops within required time.




I suppose you're still allowed to fit wobble washers. I've made my own
in the past if I wanted a specific groove size. 47 mm is pushing it though!

Did they actually ban dado sets though? or just specify a maximum stop time?

Both.

Industrial woodworking machines have a maximum time for the blade to come to rest, and this applied retrospectively, hence many machines with DC braking retrofitted.

I think dadoes were also banned in industry (i.e. you had to discontinue using them), *and* a maximum length of arbor specified for all new machines sold.

On Monday, 2 September 2013 13:51:00 UTC+1, Rick Hughes wrote:
On 02/09/2013 13:28, John Rumm wrote:

On 02/09/2013 12:08, wrote:



AIUI since the HSE banned the use of dadoes, they did it by



Did they actually ban dado sets though? or just specify a maximum stop

time?



specifying the max length of arbor on new table saws on sale - not by

banning the sale of dadoes.



Does not seem to be a problem on my 1948 Unisaw ;-)







Did admit to being tempted with the large number of Wadkin saws on ebay

... incl the tilting table versions

I bought an old 3 phase Startrite bandsaw and fitted an inverter to run it off single phase. When I have a suitable location there'll be a Wadkin or similar mahoosive old-british table saw too.

Does not seem to be a problem on my 1948 Unisaw ;-)

I'm not sure maximum permitted stopping time improves safety that much on table saws.

As they say - it's stopped when you can count the teeth.

I think the problem was more spindle moulders (along with high background noise environments), where it isn't so difficult to put fingers into a more-or-less-invisible rotating cutter.

On 02/09/2013 17:10, wrote:
Does not seem to be a problem on my 1948 Unisaw ;-)

I'm not sure maximum permitted stopping time improves safety that much on table saws.

As they say - it's stopped when you can count the teeth.

I think the problem was more spindle moulders (along with high background noise environments), where it isn't so difficult to put fingers into a more-or-less-invisible rotating cutter.



I'm surprised Elfin Safley has not tried to do something about Routers
....... hell of a speed, and no guard what so ever.

+1

+2

Kerfing out is a good solution.

On 02/09/2013 10:11, Huge wrote:
On 2013-09-02, The Medway Handyman wrote:
On 01/09/2013 23:08, Rick Hughes wrote:
I have a reasonable number of notches to be cut into 100 x 47 timbers

Want to cut cross slots 30mm deep so timbers will slot over some 200 x
47 beams, good enough for glue joints.

Want to do the job neatly, and I have 28 of them to do.


I notice that whenever they need to do this sort of thing on any of the
US shows (New Yankee Workshop for example) the use a Dado blade in a
bench saw.
I'm pretty sure you can't fit a Dado blade to most domestic saw benches
(I have a JCB model) only the large commercial machines.

Dado blades aren't allowed in the UK because of Effin Softy.

You're kidding, right? A google search yields dozens of UK sources.


You may be able to buy dado sets, but you would find it hard to buy a
table saw that they will fit.

"the blade must come to a standstill within 10 seconds of the machine
being stopped".

Is the problem, the extra weight of a dado set causes it to over run.

--
Dave - The Medway Handyman www.medwayhandyman.co.uk

On 02/09/2013 18:52, wrote:

+1

+2

Kerfing out is a good solution.


Kerfing - that's the word I was looking for :-)


--
Dave - The Medway Handyman www.medwayhandyman.co.uk

"The Medway Handyman" wrote in message
...
On 02/09/2013 06:16, harryagain wrote:
"Rick Hughes" wrote in message
...
I have a reasonable number of notches to be cut into 100 x 47 timbers

Want to cut cross slots 30mm deep so timbers will slot over some 200 x
47
beams, good enough for glue joints.

Want to do the job neatly, and I have 28 of them to do.


I notice that whenever they need to do this sort of thing on any of the
US
shows (New Yankee Workshop for example) the use a Dado blade in a bench
saw.
I'm pretty sure you can't fit a Dado blade to most domestic saw benches
(I
have a JCB model) only the large commercial machines.

What is the neatest & consistent way of doing these ........ I know I
could mark out, use saw table to make shoulder cuts and chisel out the
rest ... but this will be slow and probably not end up as neat as I
want.


I do have a Router table with a Trend T7 ... but not sure if there is an
easy way to use that. Certainly don't have a 47mm wide bit, so it would
require moving wood and bit several times - possibly end up inaccurate.


Any tips & hints ?

This is a poor method of jointing and not to be be recommended for
strucural
work as it significantly weakens the whole job.

Bollox. Utter bollox

All traditional woodworking joints significantly weaken the wood due to the
amount of timber that has to be cut away.
Mortice/bridle/halving joints are the very worst for this. Dovetails are
only slightly better.
Gang/plate nails, hangers, timber connectors are a minimum of 50% stronger
(in some cases 1000% stronger) and are faster to use.
In most cases the joint is far stronger than the timber.
Loads are better distributed in the timber hence the joints are much less
likey to fail.
There are other advantages too, eg joists need no longer penetrate the inner
leaf making the house draught proof and protecting the timber from damp.
In practice much less timber is needed hence the job is cheaper as well as
quicker.
They also lend themselves to machine shop assembly of factory made
components (eg trusses)
They just look like **** but where they are hidden, it matters not.

Anybody that doen't know this needs to get some education/training.

On 02/09/2013 17:02, wrote:


Did they actually ban dado sets though? or just specify a maximum
stop time?

Both.

Industrial woodworking machines have a maximum time for the blade to
come to rest, and this applied retrospectively, hence many machines
with DC braking retrofitted.

I think dadoes were also banned in industry (i.e. you had to
discontinue using them), *and* a maximum length of arbor specified
for all new machines sold.

Yup I was aware of the time limitation, and also the short arbour
problem. Just not sure if there was actually an industrial ban on dadoes
as such. They don't strike me as particularly dangerous (compared to
wobble blades say).


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 02/09/2013 20:26, The Medway Handyman wrote:
On 02/09/2013 10:11, Huge wrote:
On 2013-09-02, The Medway Handyman wrote:
On 01/09/2013 23:08, Rick Hughes wrote:
I have a reasonable number of notches to be cut into 100 x 47 timbers

Want to cut cross slots 30mm deep so timbers will slot over some 200 x
47 beams, good enough for glue joints.

Want to do the job neatly, and I have 28 of them to do.


I notice that whenever they need to do this sort of thing on any of the
US shows (New Yankee Workshop for example) the use a Dado blade in a
bench saw.
I'm pretty sure you can't fit a Dado blade to most domestic saw benches
(I have a JCB model) only the large commercial machines.

Dado blades aren't allowed in the UK because of Effin Softy.

You're kidding, right? A google search yields dozens of UK sources.


You may be able to buy dado sets, but you would find it hard to buy a
table saw that they will fit.

"the blade must come to a standstill within 10 seconds of the machine
being stopped".

Is the problem, the extra weight of a dado set causes it to over run.

Not a problem with active braking on the saw though. Even my 12" SCMS
has that to stop it in ten secs.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

Yup I was aware of the time limitation, and also the short arbour

problem. Just not sure if there was actually an industrial ban on dadoes

as such. They don't strike me as particularly dangerous (compared to

wobble blades say).


I think the HSE wanted to stop the practice of "dropping on" to form closed cuts.

I'm sure I've read all this in HSE information leaflets, but my memory of them is hazy.

On 02/09/2013 22:13, harryagain wrote:
"The Medway Handyman" wrote in message
...
On 02/09/2013 06:16, harryagain wrote:
"Rick Hughes" wrote in message
...
I have a reasonable number of notches to be cut into 100 x 47 timbers

Want to cut cross slots 30mm deep so timbers will slot over some 200 x
47
beams, good enough for glue joints.

Want to do the job neatly, and I have 28 of them to do.


I notice that whenever they need to do this sort of thing on any of the
US
shows (New Yankee Workshop for example) the use a Dado blade in a bench
saw.
I'm pretty sure you can't fit a Dado blade to most domestic saw benches
(I
have a JCB model) only the large commercial machines.

What is the neatest & consistent way of doing these ........ I know I
could mark out, use saw table to make shoulder cuts and chisel out the
rest ... but this will be slow and probably not end up as neat as I
want.


I do have a Router table with a Trend T7 ... but not sure if there is an
easy way to use that. Certainly don't have a 47mm wide bit, so it would
require moving wood and bit several times - possibly end up inaccurate.


Any tips & hints ?

This is a poor method of jointing and not to be be recommended for
strucural
work as it significantly weakens the whole job.

Bollox. Utter bollox

All traditional woodworking joints significantly weaken the wood due to the
amount of timber that has to be cut away.
Mortice/bridle/halving joints are the very worst for this. Dovetails are
only slightly better.

Bollox again. If the joints are glued as the OP stated, the joints will
be stronger than the timber.

Gang/plate nails, hangers, timber connectors are a minimum of 50% stronger
(in some cases 1000% stronger) and are faster to use.
In most cases the joint is far stronger than the timber.

Bollox. They are used because they are quick & require no great skill.

Loads are better distributed in the timber hence the joints are much less
likey to fail.
There are other advantages too, eg joists need no longer penetrate the inner
leaf making the house draught proof and protecting the timber from damp.
In practice much less timber is needed hence the job is cheaper as well as
quicker.
They also lend themselves to machine shop assembly of factory made
components (eg trusses)
They just look like **** but where they are hidden, it matters not.

Anybody that doen't know this needs to get some education/training.

Education & training? Get some.




--
Dave - The Medway Handyman www.medwayhandyman.co.uk

"The Medway Handyman" wrote in message
...
On 02/09/2013 22:13, harryagain wrote:
"The Medway Handyman" wrote in message
...
On 02/09/2013 06:16, harryagain wrote:
"Rick Hughes" wrote in message
...
I have a reasonable number of notches to be cut into 100 x 47 timbers

Want to cut cross slots 30mm deep so timbers will slot over some 200 x
47
beams, good enough for glue joints.

Want to do the job neatly, and I have 28 of them to do.


I notice that whenever they need to do this sort of thing on any of
the
US
shows (New Yankee Workshop for example) the use a Dado blade in a
bench
saw.
I'm pretty sure you can't fit a Dado blade to most domestic saw
benches
(I
have a JCB model) only the large commercial machines.

What is the neatest & consistent way of doing these ........ I know I
could mark out, use saw table to make shoulder cuts and chisel out the
rest ... but this will be slow and probably not end up as neat as I
want.


I do have a Router table with a Trend T7 ... but not sure if there is
an
easy way to use that. Certainly don't have a 47mm wide bit, so it
would
require moving wood and bit several times - possibly end up
inaccurate.


Any tips & hints ?

This is a poor method of jointing and not to be be recommended for
strucural
work as it significantly weakens the whole job.

Bollox. Utter bollox

All traditional woodworking joints significantly weaken the wood due to
the
amount of timber that has to be cut away.
Mortice/bridle/halving joints are the very worst for this. Dovetails are
only slightly better.

Bollox again. If the joints are glued as the OP stated, the joints will be
stronger than the timber.

Gang/plate nails, hangers, timber connectors are a minimum of 50%
stronger
(in some cases 1000% stronger) and are faster to use.
In most cases the joint is far stronger than the timber.

Bollox. They are used because they are quick & require no great skill.

Loads are better distributed in the timber hence the joints are much less
likey to fail.
There are other advantages too, eg joists need no longer penetrate the
inner
leaf making the house draught proof and protecting the timber from damp.
In practice much less timber is needed hence the job is cheaper as well
as
quicker.
They also lend themselves to machine shop assembly of factory made
components (eg trusses)
They just look like **** but where they are hidden, it matters not.

Anybody that doen't know this needs to get some education/training.

Education & training? Get some.

I have qualifications in woodwork and mechanical engineering thanks.

This stuff is all well known. Has been for years.

Have a read at this and start your education.
http://research.ttlchiltern.co.uk/pi...pdf/2-3_51.pdf

On Tuesday, September 3, 2013 8:32:06 AM UTC+1, harry wrote:
"The Medway Handyman" wrote in message

...

On 02/09/2013 22:13, harryagain wrote:

"The Medway Handyman" wrote in message

...

On 02/09/2013 06:16, harryagain wrote:

"Rick Hughes" wrote in message

...

I have a reasonable number of notches to be cut into 100 x 47 timbers



Want to cut cross slots 30mm deep so timbers will slot over some 200 x

47

beams, good enough for glue joints.



Want to do the job neatly, and I have 28 of them to do.





I notice that whenever they need to do this sort of thing on any of

the

US

shows (New Yankee Workshop for example) the use a Dado blade in a

bench

saw.

I'm pretty sure you can't fit a Dado blade to most domestic saw

benches

(I

have a JCB model) only the large commercial machines.



What is the neatest & consistent way of doing these ........ I know I

could mark out, use saw table to make shoulder cuts and chisel out the

rest ... but this will be slow and probably not end up as neat as I

want.





I do have a Router table with a Trend T7 ... but not sure if there is

an

easy way to use that. Certainly don't have a 47mm wide bit, so it

would

require moving wood and bit several times - possibly end up

inaccurate.





Any tips & hints ?



This is a poor method of jointing and not to be be recommended for

strucural

work as it significantly weakens the whole job.



Bollox. Utter bollox



All traditional woodworking joints significantly weaken the wood due to

the

amount of timber that has to be cut away.

Mortice/bridle/halving joints are the very worst for this. Dovetails are

only slightly better.



Bollox again. If the joints are glued as the OP stated, the joints will be

stronger than the timber.



Gang/plate nails, hangers, timber connectors are a minimum of 50%

stronger

(in some cases 1000% stronger) and are faster to use.

In most cases the joint is far stronger than the timber.



Bollox. They are used because they are quick & require no great skill.



Loads are better distributed in the timber hence the joints are much less

likey to fail.

There are other advantages too, eg joists need no longer penetrate the

inner

leaf making the house draught proof and protecting the timber from damp.

In practice much less timber is needed hence the job is cheaper as well

as

quicker.

They also lend themselves to machine shop assembly of factory made

components (eg trusses)

They just look like **** but where they are hidden, it matters not.



Anybody that doen't know this needs to get some education/training.



Education & training? Get some.



I have qualifications in woodwork and mechanical engineering thanks.



This stuff is all well known. Has been for years.



Have a read at this and start your education.

http://research.ttlchiltern.co.uk/pi...pdf/2-3_51.pdf



Yes I had a read of that and could find no mention of superiority of metal brackets to traditional joints. It appears to confirm that the main advantage of this jointing system is ease of use on and off site.

While their load bearing capacity may be adequate in one plain their ability to resist twist or stress in the non designed for planes would be less than the glued cross halving joint under discussion.

To me they always looked like a cheap alternative to doing the job right especially as the report raises concerns with incorrect site practices, (i.e.) using plaster board nails or not using enough nails

All traditional woodworking joints significantly weaken the wood due to the
amount of timber that has to be cut away.
Mortice/bridle/halving joints are the very worst for this. Dovetails are
only slightly better.

Bollox again. If the joints are glued as the OP stated, the joints will
be stronger than the timber.

This is becoming rather contentious, but it's not true to say a glued joint will be stronger.

A glued joint *can be* stronger, if the joint is well designed, has very close tolerances, the glue is used exactly as the manufacturer recommends, and a high clamping force is used. That's pretty much what engineered timber does, but requires carefully controlled conditions to achieve it.

Any significant notch in machine strength graded timber has to be regarded as considerably reducing its strength. The effects of a deep notch aren't very predictable.

On 03/09/2013 12:02, wrote:

All traditional woodworking joints significantly weaken the wood due to the
amount of timber that has to be cut away.
Mortice/bridle/halving joints are the very worst for this. Dovetails are
only slightly better.

Bollox again. If the joints are glued as the OP stated, the joints will
be stronger than the timber.

This is becoming rather contentious, but it's not true to say a glued joint will be stronger.

A glued joint *can be* stronger, if the joint is well designed, has very close tolerances, the glue is used exactly as the manufacturer recommends, and a high clamping force is used. That's pretty much what engineered timber does, but requires carefully controlled conditions to achieve it.

Any significant notch in machine strength graded timber has to be regarded as considerably reducing its strength. The effects of a deep notch aren't very predictable.



AS my description may have caused this 'debate' .... here is a sketch of
the joint I will use.

http://tinyurl.com/odmhukq

This is a Pergola project ... a number of 100x100 posts fitted to ground
brackets, running along top edge of posts on each longitudinal side is a
200x47 beam.

At 90 deg to this beam are the 100x47 'joists' which I intend notching
out to the 30mm shown.
These will be glue fitted ... probably use Polyurethane, as it's foaming
will also seal any gaps form water ingress.

On Tuesday, 3 September 2013 14:51:43 UTC+1, Rick Hughes wrote:
On 03/09/2013 12:02, wrote:



All traditional woodworking joints significantly weaken the wood due to the

amount of timber that has to be cut away.

Mortice/bridle/halving joints are the very worst for this. Dovetails are

only slightly better.



Bollox again. If the joints are glued as the OP stated, the joints will

be stronger than the timber.



This is becoming rather contentious, but it's not true to say a glued joint will be stronger.



A glued joint *can be* stronger, if the joint is well designed, has very close tolerances, the glue is used exactly as the manufacturer recommends, and a high clamping force is used. That's pretty much what engineered timber does, but requires carefully controlled conditions to achieve it.



Any significant notch in machine strength graded timber has to be regarded as considerably reducing its strength. The effects of a deep notch aren't very predictable.







AS my description may have caused this 'debate' .... here is a sketch of

the joint I will use.



http://tinyurl.com/odmhukq



This is a Pergola project ... a number of 100x100 posts fitted to ground

brackets, running along top edge of posts on each longitudinal side is a

200x47 beam.



At 90 deg to this beam are the 100x47 'joists' which I intend notching

out to the 30mm shown.

These will be glue fitted ... probably use Polyurethane, as it's foaming

will also seal any gaps form water ingress.

What span on the 100*47 timbers?

Notching them to a third of their depth will considerably weaken them.