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Michael Shepherd | 1 Nov 2008 23:55
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Hello and questions about squaring sandstone

Good afternoon to all:

My Name is Michael Shepherd, I became interested in stone masonry and
sculpting after two trips to Italy. I am a student studying Civil
Engineering in Colorado full time, and have read a variety of books on
stone, from engineering analysis's of arches, vaults, etc in large
ecclesiastical structures, to books written by masons describing the
process of building with random rubble. These books peaked my interest
and intrigued me to begin working with stone.
     I have over a few months acquired a few carbide tipped tools from
trow and holden, and today I began in earnest to work on just squaring
up a piece of sandstone . The sandstone I am working with is a very
fine grained (0.2 mm or so, like beach sand) variety that has a
siliceous cementing agent quarried here in Colorado. I read through
many of the post on here about squaring up a block, as well as many
post about sandstone and how it is worked, with this in mind I decided
to give it a try.
     I began with a felt marker made a line and started to cut to it
using a 3 lb hammer and a hand tracer. I made several light blows to
seat the carbide then started to lay into it. It broke but not as
cleanly as I would have liked. I flipped the stone over and decided to
try and use a hand set to get rid of the ridge sticking out of the
side. The stone broke erratically and actually snapped behind the line
I had drawn. So I tried another side of the block and decided to again
use the tracer, but from both sides instead. It worked okay but I was
left with this ridge that was sticking out part of the way and a
concave section in other places. I tried to  get rid of the ridges on
the side by using a point, cutting a small flat section and running
down the length of the side with the chisel. After achieving a section
of relatively flat area I got close to the edge and knocked a large
(Continue reading)

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David Modine | 2 Nov 2008 01:45
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Testing new computer

Just making sure I have settings correct
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edie heller | 2 Nov 2008 00:51
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Re: Testing new computer

yep, it seems to be working david ... edie

On Nov 1, 2008, at 5:45 PM, David Modine wrote:

> Just making sure I have settings correct
>
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Clive Murray-White | 2 Nov 2008 01:21
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Re: Testing new computer

I'm testing mine too sometimes my posts go through other times they don't

Sculptor Clive Murray-White
W: www.cowwarr.com/CliveMurray-White/
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David Modine | 2 Nov 2008 13:31
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Re: Testing new computer, thanks & a question

Sorry for the OT post.  I'm setting up my new computer at home, and I 
have so many different email accounts it gets tough to remember everything.
The confusion is compounded by the fact this new computer is a "Vista 
Home premium x64".  It has a lot of stuff I'm not too crazy about, but 
I'm mucking my way through.

To get back on topic:
Does anyone know if it's possible to change my email address with 
freelists, or do I need to set up a new account.  I intend to drop my 
 <at> erols.com account before to long.

David Modine
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George Graham | 2 Nov 2008 15:57
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Re: Hello and questions about squaring sandstone

Hi Michael,
I've done a lot of pitching of the local Medina sandstone here in western NY. The stone you are working with
sounds very similar.
The most important thing you never mentioned was the grain, or bed of the stone, which effects every thing
you do to the piece. The Medina stone has a very pronounced grain. It's a little hard to see, but if you work
with the grain, you get very clean  smooth surfaces. Pitching against, or perpendicular to the grain will
give you exactly what you described. The resistance of the grain turns the fracture you make with any tool ,
so your break comes out the side and not the bottom. If you actually are able to force the break past the half
way point , then all the stone that you are pounding on will push against the stone on the bottom half, and you
end up with huge undercutting.
A side note here is that all of the old sandstone buildings in this area that are well over 100 years old, have
the bed or grain of all the stones laying horizontal. I have seen some old monuments made of this stone that
were cut so the bed was vertical. The oldest now have thin sheets peeling off, taking all the lettering with
it. The building blocks made by the stone cutters are still in perfect condition.
So getting back to you question, what to do about the high ridge left on the side of you block.
The answer is, nothing. It's all a matter of accepting what the stone and your tools will give you. The
thicker the slab you are working on the higher the ridge. Its common for a 10 inch thick block to have a ridge
sticking out 3 and 4 inches. If you do all the pieces the same way you end up with an amazingly rich textured
wall. If you want to get rid of the ridge, you have point , chisel or grind it off. All these options leave you
with tool marks.
A standard way to pitch any stone, and sandstone in particular, is to lay out your stone, leaving a couple of
inches to pitch away. Use a hand set for the first cut, keeping about 1/2 inch off your line. Try to get flakes
that break out almost half way down the side. Then flip the stone over and use your handset right on the line
and try to get flakes that reach your work from the other side. Clean up you line with a chipper. Then flip the
stone back to your first side and clean up that 1/2 inch you left on the top with your chipper. You leave that
last because you may have a deeper chip that will make you move your final chipper line in. 
All the good work that you just did can all be ruined by poor corner work. I use a 1" hand set to pitch as close as
possible to the vertical corner lines. You have to clean up the corners with the hand set in a way that keeps
the tool marks inside the area that will be removed when you use the tracer to to cut that fine vertical line
that makes your block look square.
(Continue reading)

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Don Dougan | 2 Nov 2008 16:35
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Re: Hello and questions about squaring sandstone

Hi Michael,
Welcome to the list, and to 'the dust.'
Sounds like you are learning the best way (the hard way), about what happens
in carving.  Which is to say that things don't always go the way you want
them to when carving . . . <grin>

Each type of stone is different, and the 'grain' or bedding layers will have
a lot to do with your success or lack of it in working each of the six faces
of your block.  Sandstone is not something I work very often -- so I cannot
give you too many specific pointers.

But here are some general tips for squaring-up:

Your pitching tool (hand set) is designed to work only on smooth-sawn
surfaces.  It is usually a trade-off between the degree of control-of-cut
and the size/amount of waste that is to be removed in one blow — the more
you want to remove the less control you have; the less you want to remove
the greater the amount of control.  Finding that balance for each type of
stone when pitching is the trick.  Generally, pitching down through the
bedding layers will allow greater (more predictable) control, while pitching
surfaces into or across the bedding planes will tend to allow much less
control with the corresponding results being much more unpredictable.

As I work primarily in marble I rarely use a tracer.  The granite-working
folks will be able to tell you much more about the use of tracers.  I have a
feeling that a tracer on sandstone will not be the most successful
approach.  Tracers are designed so as to create a weak zone through a very
specific area of the block which will tend to fracture after repeated
striking-passes with the tracer blade in the same orientation.  This seems
to work better for harder/denser and more-brittle types of stone that also
(Continue reading)

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Michael Shepherd | 2 Nov 2008 18:31
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Re: Hello and questions about squaring sandstone

George,

Thanks for the detailed response, it is much appreciated. I was using
all my tools perpendicular to the bedding of the grains because the
block I found was basically in some very odd angles, and I was trying
to square it up. So you are suggesting using the set and pitcher
perpendicular to the grain such that I am left with ridges on the
side, then taking a point and small chisel and working them
horizontally to the face I just broke ? I was wondering if I did want
to work out these bumps, should I work from the middle out or the
edges in ?  Also should I consider using a several lighter blows to
seat the hand set in the stone along the line before hitting harder ?
It seems like a lighter blow would help as well. And finally what are
your thoughts about using toothed chisels to work off high spots in
the ridges, and following it with a boaster ?
I will try again on the stone maybe later today, but I have homework
etc that I should probably do. Thanks for the advice.

Regards,

Mike
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Michael Shepherd | 2 Nov 2008 18:32
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Re: Hello and questions about squaring sandstone

Don,

Thank you for your reply, it is appreciated. I didn't purchase a
boaster or drove because I got the impression that droves and boaters
were used mostly for limestone/marble from the trow and holden
website. I guess when you have nothing to go off of in terms of word
of mouth or advice, you just watch their little 30 second videos and
assume thats just what you do and that's it. So I bought some tools
and went with that approach. You make some very good points and I have
seen some local sandstone buildings here in Denver that have the
margins around the edges tooled with droves. So I suppose I will order
some droves and a boaster. Most of the stone I was working with is
probably under a 1 foot cube, so I was thinking I should get maybe 1
inch or less tools ? Thanks again.

Regards,

Mike
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Gary Grossman | 2 Nov 2008 18:58
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Re: Testing new computer

I'm curious too about the "missing post" syndrome but from the other
direction.  My posts go through, but it's not infrequent that I don't
receive a post.  I find out about this because I do receive the responses.
I check my spam filter daily and don't find the messages there, but I've
heard others on the list complain about the same thing.  Any ideas Blimey?
cheers, g2

>
>

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Distinguished Research Professor - Animal Ecology
Warnell School of Forestry & Natural Resources
University of Georgia
Athens, GA, USA 30602

http://www.arches.uga.edu/~grossman

Board of Editors - Animal Biodiversity and Conservation
Editorial Board - Freshwater Biology
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