They're not square, and it's (quite rightly) illegal to use a square
Of course you could make one - but the tooling to do so is fairly
complex and you'd have to be aware first of all of things like _why_
you can't have a square one.
On 16 Jan 2005 14:16:41 GMT, email@example.com (Huge) wrote:
I've got a 1925-vintage army manual of field engineering (spanners,
not shovels). Fascinating read - lots of advice on how to start
hot-bulb oil engines, how many mules you'll need to bring firewood to
a field kitchen, that sort of thing. It also has a section of
carpentry for reinforcing earthworks, or building barracks. In the
chapter on woodworking machines it mentions with great emphasis the
hazards of the square-head jointer and moulding machine, how such
things are obsolete and how they're far too dangerous for a squaddie
to consider using.
The modern version is over here:
(This whole site is worth reading)
Now I've never seen a square-head machine - and I've looked. They're
so old they really have just disappeared by now. But there are still
several dangerous types of spindle moulder head around (I can show you
the chipped wall in a friend's workshop) and the PUWER 98 legislation
tried to finally stamp these out. Five years to enforce it and get up
to date, so now it's in place. I for one am quite happy about this.
Spindle moulders aren't the death-wish machines that many people
think, but they still have a huge potential for being so.
There are several problems that spindle moulder rules needed to
address: moulder head shape, tooling projection, balance, knife
retention and spin-down.
A spindle moulder is a big lump of a rotating head with a pair of flat
knives fastened to it. Because the knives are flat, they're easily
made to custom profiles.
The first moulders had square heads and the knives fastened to them on
the outside. There were no finger accidents with these - because the
rotating head had large recesses on either side (for a square isn't
round) then it soon became obvious that any "minor" finger-trimming
accident turned into the loss of a whole hand, because the head would
grab and pull it in. So square heads had to go.
Modern circular or near-circular heads don't have this same ability to
catch a whole hand. But for moulders, rather than jointers (flat
surfaces only), they may need to make a deep cut so as to form a large
moulding. Apart from the hand-grab risk, there's the regular problem
that feeding the timber in carelessly can cause a big "catch" and the
piece is thrown back out at you. So tooling now needs to have cut
limiters in place (dummy knives), which restrict the maximum exposure
of the cutter edge itself. Even so, a spindle moulder accident is
still much nastier than a jointer accident - if you have a tool that
can cut deep, you just can't make it entirely safe.
The ability to grind up new knife profiles in the workshop was itself
a source of hazard. The most common spindle accident was a home-made
knife that was out of balance or poorly held, getting thrown out of
the head and across the workshop. So there needs to be more care
about always using _pairs_ of knives, not just lead sheet
counterweights, and taking some care to balance things. PUWER now
also requires all heads to have both clamps and a secondary locking
pin or wedge. This change made most of the older spindle moulder heads
of 5+ years ago obsolete and required their replacement.
The other PUWER change was that all machines (not just moulders) must
now coast to a stop rapidly, or be fitted with brakes. Rather than the
old cast iron heads (which needed rework anyway), this encouraged
lightweight aluminium heads. There have been plenty of accidents were
stock was accidentally pushed into a "switched off" head that was
still spinning quietly some time afterwards.
To get an old 30mm or even 1 1/4" machine up to modern standards isn't
hard - you buy it a new head and tooling. Even regrinding the 1 1/4"
spindle down to 30mm isn't too expensive. I've never seen a "modern"
head in this size - the machines were ground down, not the heads bored
out. For 2" though, the sheer rotating mass can't meet the spin-down
limits without an electric brake being added - and that gets
I think I've used a 50mm machine, but that was a multi-head
multi-thousand-quid production behemoth with electric braking. The
"small workshop grade" machines are just sticking with 30mm.
Blimey. The stuff we used to use in the seventies was square head bolted
on no brakes and yes, bloody dangerous.
The foreman demonstrated it by gingerly feeding a strip of scrap into it
as it spun down - having checked no one was in the path, and it fired it
across the shop floor into a metal mesh barrier placed strategically.
I then got s small wry lecture on never ever disturbing the man on the
machine, or walking behind it unless it was silent.
Fantastic tools - we used it with shaped jigs to make guitar necks out
of rock (hard) maple - but it needed a lot of care in use. No guard
cutters - the boys had three jigs, one for each cut depth, and woe
betide if they used the deep cut first.
A spindle moulder is a large router upside down in a massive table with
usually a sliding carriage as well.
Its used to make things like ogee mouldings.
It has a large vertical spindle - in this case 50mm diameter - that does
excessive RPM, and onto which is affixed a cutter head,. This is a lump
of metal with slots cut into it at an angle, into which you can bolt
blades - like planer blades - but blades that are cut to shape - so the
whole head and cutters becomes a giant routing cutter if you like. They
are large - several inches across - and do enormous RPM, and, if the
blades catch a knot when you are standing behind em, will drive a plank
of wood right through you.
They are essentially the big brother of the router bit with a ball
bearing on it. Except you use a fence rather than the wood itself to
guide the part to be shaped.
They do relatively few rpm. The linear speed is high (although not
excessive) but because the head is such a large diameter the rpm is
pretty low. Usually top speed is about 8k, compared to 20k for a
The large cutter head diameter has a few other side-effects. They
don't form the "divots" that a small router cutter can do if the
pressure against the fence is varied, but neither can they follow
tight curves or corners.
That's the shaper, not a spindle moulder. It has a collet chuck, like
a router - often 1/2", but it may be 3/4" or 1". Some of these
overlap with smaller spindle moulders and are convertible. I've never
much liked shapers - they're too slow for turning a small "router
size" cutter and giving a good finish, and the tooling is cheaper for
spindle moulder knives than for large router cutters.
I'll be back a bit later to tell you all in a bit more detail what we
got in the end, apparently what the Americans might call <best Norm
Abraham accent> "a stacked dado head cutter", but in the meantime two
people ROTFL here too!
On Mon, 17 Jan 2005 17:52:59 -0000, "Holly, in France"
Not surprisingly, use of these is discouraged in Europe as well, for
much the same reason of having a heavy lump of metal that you can't
stop quickly, plus it being not easy to put safety devices around
Table saws sold in Europe usually have short arbours to prevent you
putting a stacked dado set on.
Use of them is constrained in Europe, but for the supplemental reasons
you mention, not because dado heads are themselves a bad idea. You
might note that it's hard to find a saw that can accept a dado head,
but you can buy the heads themselves easily enough.
I have a portable DeWalt contractor type saw which I bought in the
U.S. and imported myself. This has a long 5/8" arbour and will take
stacked dado cutters quite happily. It actually stops withing 10
seconds, even with all blades and chippers mounted.
It's legal for me to import and use for personal use, but not to
import and sell or use commercially, as I understand it.
For my Felder combination machine there is a dado option for the saw
arbour but instead of using U.S.-style stacked sets, it uses tooling
which is rather like spindle moulder tooling consisting of two halves
between which spacers can be installed. There are disposable main
and scoring cutters with four cutting edges each giving very clean
cuts and the same tooling can be installed on the spindle moulder
instead. Although the tooling is steel of about 230mm dia., the
electronic braking spins it down very quickly.
Like all of these things, it gets treated with the greatest respect,
and if I can use the power feeder, I do.
My husband was wondering about using the stacked cutters as you suggest
too, for tenons etc, but the arbour on his standards saws are too short.
Another thing for his tools wish-list then :-)
Andy, I am SO glad you described these things first! Otherwise I was
going to have to attempt it since these are what we bought. They have
two horizontal blades also for cutting smooth the 'top' and 'bottom' of
the tongue/groove as well. I really can't describe it but you will know
what I mean, perhaps that is what you mean by main and scoring cutters?
Anyway, he is going to use this same set of cutters which will cut 5-9mm
by use of spacing rings to cut both tongue and grooves in three passes
instead of the two it would have taken with the tool-holder system we
saw on the web page.
Decided against those since any damage to the blade was going to involve
new blades for T&Ging. Sharpening not practical, at least not much, for
obvious reasons with T&G. We may well get one with other cutters if we
ever have to do more mouldings than are practical with the De Walt
Interesting thing about these tool holder systems as on the web page.
You will be aware of the multi-function ones and the safety ones which
hold backing blades of the same moulding as the cutting blade, so that
only a mm or so of blade is exposed. Salesman says both are legal in
France, it's only Germany which has regulations against them.* We were
not convinced and still umming and ahhing about the safety ones. He said
that for every 90 or so ordinary ones he sells he would only sell 1
safety one, because of the cost (30euro./pair ish) of the 'contre-fers',
or backing blade thingies (what are they called in English?), has only
sold 3 in 16 years!
*don't worry, I didn't believe him!
Ours are 160mm
Ours alas will not, he will just have to be very careful. At least this
system won't 'grab' the timber so it will be better that the standard
American cutters from that point of view.
Thanks very much for all your input into this Andy, you have been very
helpful, as have others.
On Tue, 18 Jan 2005 16:11:52 -0000, "Holly, in France"
I'm not sure about using one of these for tenon cutting. The typical
method that I have seen for this on a saw is to have a jig which
clamps the wood vertically and runs in one of the mitre slots.
If you look at
The scoring cutters are the ones fitted to the top, square in shape.
They can be removed and rotated to get a new edge. The purpose is to
get a clean edge to the cut.
The main cutters are the vertical ones on this block. Normally these
are reversible once.
I don't either. I am not sure whether it's a case of actually being
legal or illegal in France, although there may be an obervance issue.
At any rate, I always buy and use the limiters. As I say, wherever
possible I use the power feeder, or failing that various other safety
devices to keep fingers well away. With something like this, any
safety device that is practicable should be used as far as I'm
It has taken me ages to get around to this, but in case you are
interested I have put a picture of the cutters we bought here:
It's not very clear but I think you can see what is what.
There is also a picture of a DIY boat, the kids have been watching too
much Scrapheap Challenge :-)
Holly, in France.
Holiday home in the Dordogne,
website: http://la-plaine.chez.tiscali.fr /
I was talking about something like:
Once again I haven't done the tinyurl thing but it's short enough to be
able to paste together IMO
Given the difference in prices and availability, that might possibly be
an option depending on the exact structure of the thing. However, I
suspect there might not be enough metal to do it without weakening it or
some other problem would arise, and boring it out wouldn't be a diy job
(for us anyway) so by the time we had found and paid someone to do it
and waited for it and........it might be just easier to buy the right
thing in the first place.
Holly, in France.
Holiday home in the Dordogne,
website: http://la-plaine.chez.tiscali.fr /
On Sun, 16 Jan 2005 17:18:37 -0000, "Holly, in France"
If you look at the diameters of the two blocks you mentioned, the 50mm
bore one is 120mm overall diameter, whereas the 30mm one is 10mm
diameter, which implies the same amount of material in the centre of
I think that it would be pretty unwise to bore out a 30mm block to
50mm, because there would be little left.
You really don't want the tooling disintegrating at 6000rpm......
It is what I would call a serious machine, see my reply to Andy Hall,
but I'm not very familiar with them and I have no idea about the soft
electric braking! >
Yes, 30mm seems to be much more easily available here too, but 20mm and
50mm are not uncommon it would appear. The site suggests using more
readily available 30mm ones on a 20mm shaft by using reducers, which
they also sell. Shame it's not so easy to solve the problem the other
way around! I also found a paragraph on the hmdiffusion site which might
be of intereste and translates roughly as follows:
Many diameters of holders are available on spindle moulders:
20mm - this has for a long time been the diameter adopted by machines
for amateurs. On finds many of these machines for sale secondhand but be
aware that there are practically no more tools made in 20mm diameter and
that the new types of tools are all in 30mm. There remains the
possibility of using 30mm tools on a 20mm shaft using reducing rings.
30mm - this is now the standard the most used and one finds the biggest
range of tools. It is used as much by the professional as by the
50mm - a diameter specific to France and largely used in the trade. A
number of amateurs are tempted by the purchase of a secondhand machine.
It is necessary to point out that these are heavy and indestructable
machines that one can often buy inexpensively. But, pay attention to the
following: the tools in diameter 50mm are well outside the normal price
range, so what one gains in buying one of these machines one can lose on
the other side.
So that explains alot then :-) Hope it was of interest to someone!
On Sun, 16 Jan 2005 17:53:27 -0000, "Holly, in France"
The issue is that the rotating tool, must, according to the machinery
regulations (probably the same in France), come to rest within a
certain time (IIRC 10 seconds after pressing the stop or emergency
If the block is large and steel, this may not be achievable simply by
cutting the power to the machine.
To address this, many machines have electric or electronic braking.
Essentially, this usually works by having a box of electronics between
the mains power going in and the motor. Then when you press the stop
button, the electronics forces a fairly rapid decelleration of the
motor to a stop in a few seconds. Some also provide speed control.
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