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grindopedia

toolcollage3-1

Air Hammers

TrowellHolden-air_hammers

Part of this material I used in the 20 hour granite course I taught at Pratt. Most of the info is from Tom Urban's workshop at Camp Brotherhod, some from a workshop by Don Ramey that Hank Nelson organized at my place years ago. If you find anything useful, please add it to the article - Kirk

Pneumatic hammers

Sources: 


Types:

  • D (Dallet) long stroke 3/4 “, 1 inch.  Used for removing lots of stone.  More impact, vibration.
  • B short stroke 1/2, 3/4, 1 inch.  Less vibration, used for detail.
  • Bantam-fine detail, lettering
  • Many carvers use 3/4D, control impact by amount of air.

Air consumption:

Read more ...

Splitting Granite

Part of this material I used in the 20 hour granite course I taught at Pratt. Most of the info is from Tom Urban's workshop at Camp Brotherhod, some from a workshop by Don Ramey that Hank Nelson organized at my place years ago. If you find anything useful, please add it to the article - Kirk

Granite is removed either by impact or by abrasion, not by carving through the stone. Stone will break and carve more easily in one direction, known as the “grain”.  Slabs are usually sawn so grain runs long way, thus breaking is across the grain

Granite tends to split towards an edge.  The closer you are to an edge with splitting tool, the more the crack tends to run to the outside rather than down through the stone.

Depending upon the situation and piece of stone, three techniques can be used: "Plugs and Feathers", "Saw Cuts and Weges", and " Pitching"

(Anyone have photos of feathers/wedges and pitching tools they are willing to contribue/post)

Read more ...

Glazed Diamond Segments

Image Courtesy Situp.com

When using a diamond core drills, drilling stone,  I found out that often the rate of drilling would slow, even when applying more pressure. The problem would continue to get worse, especially when drilling dense stone such as basalt.

The sintered diamond tips had become glazed. 

Although oriented to "concrete" this link (which just well could be called "hard stone vrs soft stone sintered diamond blades") provides an article with images that show what's happening so you can tell what the problem is. 

How to "fix" the mismatch between stone hardness and sintered matrix can be found at this link (Image linked from the situp.com.au site)

The take away from 'glazed diamonds' is that "dressing a diamond tool" is something you may need to do, and that you may need a different "dressing stone" for each of your blades/cores/cupwheels. 

(Some manufactures claim their tools do not need dressing, because of propietary techniques, maybe the NWSSA veterans can shed light on this topic)

Sanding Mandrels - Roll Your Own

mandrel_IMG_0018_s

Sanding mandrels are very useful in grinding, rounding, and sanding the upper inside lips of stone vases. The transition between a flat surface and a core-drilled hole is usually sharp, rough, or even damaged. The mandrel on a die grinder allows you to shape, sand and polish this area.  Presented below is how to make and use your own sanding mandrels.

mandrel_IMG_0019_s

 

 

This is the way that I make ¼ inch sanding mandrels for die grinders: I start off with ¼ " round stock and cut a slot down the center to hold the sanding belt in place. Then I insert the belt end and tightly roll the belt on to the mandrel, stopping when the diameter is the same as that of the crimping ring. I then crimp the ring onto the sanding belt material.

I've broken the article into five parts:  The Mandel, Sanding Material, the Crimpers, Construction, and Usage

 

Read more ...

Saftey - Working Safe Check List

Organize your actions around safe behavior to protect yourself.

PROBLEM

PREVENTION

LONG-TERM

Free silica  - Wear respirator
Noise  - Hearing protection
Repetitive stress injuries  - Physical: “pacing,” posture, stretching
IMMEDIATE

Eye injury  - Safety goggles or face shield that fit over respirator
Back injury  - Lift properly
Repetitive stress injuries  - Physical: “pacing,” posture, stretching
SPECIFIC TOOLS

  Diamond saw:
Blade breakup  - Check for cracks, don’t jam or overheat
Abrasions, cuts  - Avoid kickback
  Air hammers:
Reynaud’s disease  - Padded gloves, relaxed grip

GENERAL

  • Have eyewash and first aid kits or know where they are if not working in your own studio/shop.
  • When working with others, pay attention to where they are and what they are doing.
  • Don’t work when fatigued

SAFETY: How To Wear Soft Foam Earplugs

ROLL, PULL, HOLD - not exactly STOP DROP ROLL

At our Monday morning safety meeting, a few years ago, the subject of the week was Hearing Protection. The company safety officer covered all of the require elements of hearing protection and that along with the documentation sufficed the annual yearly training requirement. ROLL-PULL-HOLDThe difference this time was that a salesman from a custom hearing protection company was there. He asked for a few volunteers to come forward and demonstrate how they install foam ear plugs. He was lucky and got a volunteer, Bret. Bret rolled his ear plugs and stuffed them in his ears as all of us had done in the past. The salesman showed that much of the ear plug was not in the ear and the the protection was poor at best. He then showed us how to properly install ear plugs.

Here's the video of what he showed us:  ROLL, PULL, HOLD  

and a breif description: NIOSH Mining: NIOSH Roll-Pull-Hold technique for earplugs | CDC/NIOSH

It's the small things over time that make a difference.

Diamond Tool (UKAM) Links

Here are some links to information about diamond tools that I found is informatiive and useful.- (Pat Barton-)

Note: Maybe UKAM would become a supporter of this project, that we are working on, and also NWSSA.

Getting the most from your Diamond Tools

Getting the Most from your Diamond Sawing Operation  Has good information on saw use. safety, and how to make your blades last longer.

Getting the Most from your Diamond Drilling Operation

Select the Right Diamond Blade for your Application

Select Right Diamond Drill

Optimizing your Diamond Drilling Operation

Getting the Most from your Diamond Blades / Diamond Sawing Operation

Diamond Drill usage suggestions and recommendations

Selecting the right Diamond Drill for your application

How to properly use Diamond Drills & Diamond Drill Bits (543kb) 

Diamond Blade Guide & Getting the most from your Diamond Blades

Selecting the right Diamond Blade for your application

 

(Although maybe self explanitory, it would be useful to have a one sentance intro to each article as to why or what the article enlightens us about.  Also has anyone done a compare and contrast on this manufacturuer vrs others?  Also, I forwarded this on to Gerda for follow-up.)

Die Grinders


Die Grinders At A Glance

Commentary

For who:
  1. Metal workers to smooth out irregularities. Polishing
  2. For sculptors to do the finer work, more precise work than with an angle grinder or bench grinder.
Makes available:
Metabo, Makita, de Walt and others
Speed:
Variable: 2000 – 7000,  7000 – 25000
Constant. 10.000 0r 25.000.
(All approximate numbers)
Power:
in amps.  5 – 13
Weight:
4 – 5.5lbs.
Length:
up to 13 inches
Suppliers:
Many (See NWSSA List)
What “bits” to use:
 Adaptor for 5/8”
Price:

Ease of use:

metabo900plusThe Die Grinder
This is a handheld power tool used to grind material off usually die’s which are part of the manufacturing process of e.g. car fenders, coins or blister packs. The use of grinders by stone sculptors is not well known. They are used to smooth edges and surfaces in industry. In stone sculpting there are many other applications depending on burs, sculpting tools or points, wheels or drill bitts. Confused?  I still am. My suggestions is to get two or three catalogues from suppliers who cater to us such as Trow and Holden, “A Cut Above”, Pothier and Neolithic in Vancouver, Braxton-Bragg in Nashville.  The terminology may become clearer.

Trade names of die grinders are Makita, de Walt, Metabo, Bosch, Dremmel, and Foredom, etc.

Sizes

Vary from an 18 oz. 1.6 amps. Dremel, (5000 to 35000rpm) to a Makita GD 0600. 3.5 lbs., 3.5. amps. or a Metabo 900 plus 3" with a weight of 5.3 lbs. and 7.5 amp., 2500 to 6000 rpm and others up to 15 amps. and/or 27000 rpm. There are numerous models for numerous prices. One needs to make up one's own mind after research what to go after.

Following is information I acquired during the decision making process to get one making ample use of advice received on the listserve of the NWSSA.

What sculpting does one want to do?

The die-grinder will assist in the finer work and smaller spaces such as "cavities" and holes. The collet is only ¼" so no large burrs, discs or points can be used. " Cut Above" sells and adaptor that goes from a ¼" shaft to a 5/8" screw that will take anything that goes on the angle grinder. I think it would be wise to put nothing bigger in this than with a diameter of 2" as balance may be lost especially at higher speeds.(10000 plus).angle die grinder

How large a stone you are working on?

The smaller the stone the finer the work, the bigger the stone the larger the tools can be. I am a under hundred pounds guy, the stone that is. If you are working on a 500 lbs stone then it becomes a different issue. Two factors are involved here. One, the amount of stone that might have to be removed and the "fine-ness of finish you want to get. The die grinder is more for the end-stage work and for the creation of crevasses and holes.

Hardness of the stone.

Soapstone goes very quickly, granite is another mater. I have no experience beyond marble but on the list serve there are comments helpful in that respect.

Consequently opinions vary regarding speed or R.P.M. See list serve comments. I went for 2000 to 8000 RPM. For me that is plenty since I do not go beyond marble or similar hardness. I can well imagine that those who work on granite need a faster machine to get anywhere.

die     grinder

My Choices

The internet has been very useful to me getting questions around this subject but the list serve of the NWSSA was and is very usefull.

To close I bought a metabo 900 plus 3. It is long, relatively heavy but works perfectly. Especially it does not slow down when you put a lot of pressure on the point when grinding. Also at these speeds relatively little dust is created so the athmosphere remains bearable. I do always use a facemask and filters. I have drilled holes with it and again lots of power. I have used silicone-carbide stones with success on the adaptor. In general, I am happy.

A Final Remark.

Water can be used with electric tools but do it carefully and don't tell the inspector. Those who use "airpower" having big compressors can use air tools. The tools are cheaper but the compressors are expensive (7 HP and up) and are grossly inefficient energy wise.

 

The Die Grinder

 

 

 

Trade names of die grinders are Makita, de Walt, Metabo, Bosch, Dremmel, and Foredom, etc.

 

Sizes vary from an 18 oz. 1.6 amps. Dremel, (5000 to 35000rpm) to a Makita GD 0600. 3.5 lbs., 3.5. amps. or a Metabo 900 plus  3” with a weight of 5.3 lbs. and 7.5 amp., 2500 to 6000 rpm and others up to 15 amps. and/or 27000 rpm. There are numerous models for numerous prices. One needs to make up one’s own mind after research what to go after.

 

Following is information I acquired during the decision making process to get one making ample use of advice received on the listserve of the NWSSA.

 

First of all what sculpting does one want to do. The die-grinder will assist in the finer work and smaller spaces such as “cavities” and holes. The collet is only ¼” so no large burrs, discs or points can be used. “ Cut Above” sells and adaptor that goes from a ¼” shaft to a 5/8” screw that will take anything that goes on the angle grinder. I think it would be wise to put nothing bigger in this than

with a diameter of 2” as balance may be lost especially at higher speeds.(10000 plus).

 

 

 

 

The next big question is how large a stone you are working non.

The smaller the stone the finer the work, the bigger the stone the larger the tools can be. I am a under hundred pounds guy, the stone that is. If you are working on a 500 lbs stone then it becomes a different issue. Two factors are involved here. One, the amount of stone that might have to be removed and the “fine-ness of finish you want to get. The die grinder is more for the end-stage work and for the creation of crevasses and holes.

Now we need to talk about the hardness of the stone. Soapstone goes very quickly, granite is another mater. I have no experience beyond marble but on the list serve there are comments helpful in that respect.

Consequently opinions vary regarding speed or R.P.M. See list serve comments. I went for 2000 to 8000 RPM. For me that is  plenty since I do not go beyond marble or similar hardness. I can well imagine that those who work on granite need a faster machine to get anywhere.

The internet has been very useful to me getting questions around this subject but the list serve of the NWSSA was and is very usefull.

To close I bought a metabo 900 plus 3. It is long, relatively heavy but works perfectly. Especially it does not slow down when you put a lot of pressure on the point when grinding. Also at these speeds relatively little dust is created so the athmosphere remains bearable. I do always use a facemask and filters. I have drilled holes with it and again lots of power. I have used  silicone-carbide stones with success on the adaptor. In general, I am happy. A final remark. Water can be used with electric tools but do it carefully and don’t tell the inspector. Those who use “airpower” having big compressors can use air tools. The tools are cheaper but the compressors are expensive (7 HP and up) and are grossly inefficient energy wise.

Breathing Protection

breathing_protection.jpg

Dust produced while working with stone containing silica and other harmful minerals is not just an annoying problem, it is a real concern and threat to your health as well as anyone who hangs around your dust filled studio space.  Maybe you work wet on everything, capture all the sludge run-off and keep it contained, but for those of us that do not, protective breathing should be practiced, constantly.  Learn about what's in the stone you are working, if you are uncertain then wear a filter on your face.

dust cloud

Use an N-100, not an N-95.   The 100 part means 100% of all fine particles, and 95 is 95%.  What's important to me is that for silica dust no amount of particles is acceptable, so therefore if I'm working around silica based stone - granite, it's a necessity to use N-100 and a respirator that seals against my face so all the air I breath is filtered.

Seattle University - Health and Safety Programs - Respiratory Protection Programs This link has a good section on how to check your mask for fit before use, along with all the other information that is required of industry. Fit tests at symposia should be a first day activity and maybe NWSSA should make it part of the regular program?

http://www.osha.gov/Publications/3362silica-exposures.pdf  A new OSHA publication with sections on many of the tools used in stone sculpture. They address the dust first by environmental control and last by the use of personal protective equipment.