Recently acquired a 3ph saw bench (Norsaw 1603) with 16" Trend tct blade, 40
tooth I think.
Saw needed a little fettling. After a trial run I removed blade and
delivered to sawdoctor for sharpening.
Whilst this was being done I set the saw up to my satisfaction.
Replaced the blade and tried it. Blade runs true as far as I can tell. Cuts
well enough but 2 immediate problems.
1) Sawn edge of timber is scorched on both sides. Have tried this with
various timbers from 10 to 125mm.
2) On pushing timber through the blade the far end tends to lift from the
bench. Not a good thing.
Both these problems were evident when I first got the saw and tried it.
A riving knife is fitted and all timber is well seasoned/dry.
I can only think that the blade has a bump or something but there is nothing
Any thoughts please?
Riving knife not thick enough to match kerf?
I folded a thin piece of sheet steel to widen mine.
The other question is... are you sawing high sap timber? This quickly
builds on the clearance space behind the teeth and loads the cutting
Got to agree with Tim the riving knife is probably too thin. The last bench
saw they bought where I worked came with a pair of knives one for a standa
rd blade and one for tipped blades. Has your saw doctor done a good job can
you see a set to the blade tips, we had a few bad experiences with some th
at we used in the past before we found a good one.
The blade must be exactly parallel to the table slot otherwise the teeth
on the exit side of the blade will rub on on side or other of the cut
made by the front (cutting) teeth
Usually this is set by loosening the table and tapping until a dti
registers the same from front to back of the blade body.
Final test can be done by cutting a narrow strip of wood clamped to the
mitre gauge and listing to the blade it passes the back of the blade.
You should hear a very slight noise. No noise almost certainly means it
tilted away from the cut and would burn on that side if you were rip
cutting. Lots of noise and it will be burning the end of the test piece.
Note that is the arbour bearing is worn, any attempt at setting will fail.
Fix this first.
Scorching sounds like one of two things...
Either the feed rate is too low - you need to feed the stock through
faster. (note also some wood scorch more easily than others - cherry and
maple are particularly easy to scorch IME)
Or, and this is the one I suspect given your comment about the back of
the wood lifting. you have not got the saw setup correctly, and the wood
is being pinched between blade and fence. If so this needs fixing PDQ
because not only will lit trap and scorch the wood, its also a kickback
waiting to happen.
You need to do the setup in two stages. Stage one, alight the table
surface to the blade, and then stage two, align the fence to the blade.
The first is usually done by slackening off the bolts that hold the
table, and moving it about until its mitre slots are exactly parallel to
the blade. (long straight metal rule against the blade - missing the
teeth, then use a dial indicator in a travelling sled in a mitre slot.
I'd also set up the saw with melamine-faced chipboard. Real wood sometimes will
bind fiercely on properly set up saw...
And the melamine facing will chip off where the saw comes "up" through the wood
if the saw is off true.
On Tuesday, June 23, 2015 at 11:06:18 PM UTC+1, John Rumm wrote:
Or he may have a blunt blade though I'm also more inclined to go with the misaligned theory.
Leave off the fence and push the timber through free hand.(CAREFULLY using at least one push stick) If it doesn't scorch then the fence is the problem
IME most hardwood scorches because of the resin content. I've got
various bits and bobs lying around, some of which are at least 150 years
old, and they still bleed resin when cut. I would test the blade on
sheet materials or decent quality softwood.
On Wednesday, June 24, 2015 at 9:57:43 AM UTC+1, stuart noble wrote:
Not my experience. I'm using some oak obtained when an old teacher training
college closed. Judging by the style of the construction the general fini
sh and the age of the school this furniture is at least 70 years old. Cutti
ng it on a table saw gave no burning. It mostly cane out of a lab.
There was also some pine among the items and it had the most beautiful scen
t when re-cut.
Nearly all gone now into Versailles planters.
Similar story with some native oak we re-cut out of an 8ft log some 15 year
s ago and air dried. Bugger to cut but no burning and the appearance of the
quarter sawn boards is beautiful. The reason we re-cut it ourselves was to
get the best of it quarter sawn
Good sharp blade and right speed of cut should give good resukts.
What hardwood were you using with a high resin content ?
The one I remember specifically was beech. The blade was well gummed up
after cutting. Some unspecified fruitwoods, although soft in texture,
also gave problems. I think maybe the blade hits a resin "pocket" now
and then. Actually, oak has never given me problems.
On Friday, June 26, 2015 at 10:48:03 AM UTC+1, stuart noble wrote:
Not that I doubt you for a second but I've never had a problem with resin i
n beech. The worst problems I have found were with Pine and its sisters. Tr
ouble is I'm a miserable bastard and invariably use re-cycled wood as I get
it free. But then I have to re-design things around available sections and
keep a sharp eye out for buried metals and watch that buried dowels don't
suddenly appear in the wrong place.
On Friday, 26 June 2015 13:55:42 UTC+1, fred wrote:
in beech. The worst problems I have found were with Pine and its sisters.
Trouble is I'm a miserable bastard and invariably use re-cycled wood as I g
et it free. But then I have to re-design things around available sections a
nd keep a sharp eye out for buried metals and watch that buried dowels don'
t suddenly appear in the wrong place.
I find a tct blade eats nails happily enough. I wouldn't want to cut an eas
ily rotatable metal fixing though, if it turns in mid cut you'd have a prob
On Friday, June 26, 2015 at 7:40:00 PM UTC+1, email@example.com wrote:
in in beech. The worst problems I have found were with Pine and its sisters
. Trouble is I'm a miserable bastard and invariably use re-cycled wood as I
get it free. But then I have to re-design things around available sections
and keep a sharp eye out for buried metals and watch that buried dowels do
n't suddenly appear in the wrong place.
asily rotatable metal fixing though, if it turns in mid cut you'd have a pr
Well with 300mm blades costing upwards of £150 for good ones I wouldn't b
e risking it. Lots of present day chipboard is made from re-cycled material
s so seeing the odd spark isn't unusual but I've had a whole tooth knocked
out when cutting fresh 25mm sheets.
In theory we can pay extra for virgin sheets but in reality they're like he
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