You got a mouse inside your camera .. :)
looking good Nick..
Just looking at the way you are doing it with that biax
machine ...and it occured to me ...if i was carefull ...i could do
that with an air powered 10mm finger belt sander.
..I know then, it wont be then called scraping ..but hopefully same
results..if careful...or am I wrong.
all the best.markJ
I didn't show that, sorry. It was a so called camel back. A ruler with a
broad (about 55 mm) flat side, on the other side a bowed reinforcement
(looking like a bridge).
I'll show it in the next video, or have a separate one about the tools.
On the very little bit of scraping that I have done (by hand, no Biax
unfortunately) I realise that I have not been aggressive enough at
start. Experience has proven that "relatively heavy" blueing of the
"master" and aggressive cutting pays! Otherwise one gets tired and the
job seems to go on and on.
I very much look forward to your work on the Vee. I have an Eagle
grinder (Courtesy of Charles P) that I have been slowly working on.
The Knee ways are "better" than they were but the table ways need some
work. It will never be a "perfect" machine but is a good exercise in
Anybody:- Where can I source a Sandvik Coromat hand scraper in the UK.
I am currently working with a home made, it works but not good enough.
Nick:- Is the cutting action of the Biax side to side or forward and
Thanks for the video.
But really hard cutting is kind of an art by itself. Not the cutting per se,
but knowing where to cut and keeping the really hard cutting for many
I'm not really at that level yet. But I do know when to start point spotting
and I'm quite quick at that now.
I think there are three phases:
rough cutting and
One can start with point spotting, but it will take forever. BTDT. :-/
I think the Sandvik blades are the best. Got some and they stand much longer
and make a finer cut.
Back and forth. The stroke of my BIAX (a BL40) can be adjusted, also strokes
BIAX does have several models. So if you buy one, get informed!
The "L" in "BL" stands for light cuts. But they seem to have a different
understanding of "light". Maybe they are thinking of huge machines with
millimetres to cut off. :-)
Anyhow, I'm happy with that model. It is heavy enough to scrape a rough
casting if you want. And you don't want a heavy model, considering that
you'll scrape for hours and days.
Another query Nick. What cleaning liquid do you use to clean off the
surface after scraping and before re-testing with your flat?
I know that some feel that highly volatile liquids cause cooling and
therefore distortion of the part. I admit that I use "Carb Cleaner"
(Mainly Naptha) as I always have an aerosol around.
I have tried around and found this working the best:
Normally, I use spray-on oil *like* WD-40 :-)), no not THAT ONE!. The
cheapest I can get. It's best if it has no MOS2 in it (unlike the one on
the video). I oil the *stone* (Arcansas is really the best after trying
different ones), deburr (all over the speck, swarf, blue) and then wipe off
with an rag. If that rag got dirty enough, I use it for a first wiping pass
and then go over it again with a clean(er) one.
I do know, that people say that any remains of oil are bad. But that what is
left behind this way doesn't hurt. So I don't fully agree with that.
Only if I do have problems with the blue, I use whatever solvent is in
reach, there's no difference. Aceton is working perfectly, and isn't
health-hazardous. And I like the smell. :-/
Use rags that have been washed several times, so they doesn't lose
fine "hairs" (don't know the word right now).
Clean the surface plate (where you spread the blue) and the camelback /
prism at least once a day (when you start). Fine dust is collecting on it
and the finer the work, the more you will see fine stripes of blue on the
work. Then it's time to clean all tools with a solvent.
Someone told me the trick to wipe over the granite plate with the hand.
Before spreading blue <G>. Thus, you feel any dust on it and the bit of
grease will pick up fine particles.
A short question, a long answer! :-))
And two areas on the plate.
One for spreading in initial picking up blue (a small area) and a bigger one
for picking up blue to go onto the ruler. That second area avoids
having "fat" spots of blue on the roller. Strictly speaking, you can leave
out that second area when using a ruler or prism if you get an even coat on
the ruler / prism.
But you can't leave out that second area when touching on the plate.
So the point is, that the roller is used to *transfer* blue, not to *spread*
On Mon, 02 Mar 2009 09:33:45 +0000, Richard Edwards
I got mine from Greenwood Tools. It is not in an obvious place on
their website as it's listed under milling tools!
and for spare inserts
Despite a lot of searching I've not found an 'industrial' supplier
that carries these items, the pricing on those spare inserts is
At fleeBay through an agent (read: friend). I personally never buy something
there. Call me nuts!
Again, pay attention with their models!
Taking the chance to answer a question I got by eMail (please ask here):
The rubber roller (not show in that video but an other one) is made out of
rubber. <G> I think it's PU? You get them at art shops. Has a closed
surface, nothing foamy.
Use the technique (also in that other video) with the two places for the
blue. It really works perfect.
And again a comment about rough-cutting. It seems, that it is angst*)
that you might destroy something. Even with hard strokes it is quite
complicated to remove too much. But this is a longer process to understand
learn and judge. The only place to pay attention is the boundary of the
surface. Stay a bit away from it and thus get a slightly concave surface.
With a few strokes in one pass, the "border mountains" are set back to the
inner level. Avoid chatter and try to get not too many scratches (through
Oh and to the edge:
In one of my other videos, I used a green grinding wheel. Now, I do have
some diamond wheels. Much better! There are different namings for the
grids. One that works is "D54" (or D52?). Something around that ballpark
works. But I'm still making a few strokes with a diamond lapper mesh 1200
It depends a bit of the work you are doing. I'm fine with an R90 .. R120 for
roughing and mostly an R60 (or R40) for spotting. The more acute the angle
between work and the blade is, the bigger the effective radius. If the
angle gets too big, tendency for chatter increases. With a big radius, it
is harder to exactly hit a spot. Takes some practice and I'm still having a
bit of problems with that with the BIAX, but quickly learned with a hand
I'm using that word, because I know the specific meaning for you.
I think I'll write a book. :-)
Thanks Nick, a book on CD with lots of video's would be a good idea ;-) Do
you happen to have a article number of the hand scraper? I've been
e-searching a few hours and can't find in anywhere, E-bay, Sandvik
Deutschland nor Sandvik elsewhere. Does your friend has more handscrapers in
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