EVALUATION OF TUNGSTEN-TIPPED STEEL CUTTING BLADES by RMIT INNOVATIONS
SEPTEMBER 2003 - Project No. 628776, Report No. 204

BRIEF
After discussions with Australian Saw Company a series of tests were performed on a new design of tungsten carbide tipped ROTARY HACKSAW blades for cutting steel to ascertain their cutting ability & quality of cut through a range of steel products. Three (3) steel cutting blades were supplied and tested: 210mm dia (8 1/4"), 180mm dia (7 1/4") and 103mm dia (4").

POWER TOOLS USED
The typical power tools used were an angle grinder and circular saw.

QUALITY OF CUT
The quality of cut is excellent through a wide range of steel shapes, being especially impressive when cutting thin material such as, roof and wall cladding including high tensile grades and clip lock decking. The cut is clean with negligible burrs and no deforming of the profile of the thin material, thicker materials such as angles, rolled hollow sections, tubing etc have a small uncut piece remaining after the cut similar to that of a power hacksaw cut which is easy to remove. The quality of the cut is better than that by a fibre cut-off wheel.

Virtually no heat is generated from the cut and in all cases the cut material can be handled immediately after cutting.

EASE OF USE
The first time user is wary of the claims that these blades can cut steel, but after the first cut all users were very impressed. They are very easy to use, cutting smoothly and cleanly with no shudder or vibration similar to that experienced when cutting timber, no kick back was experienced during all the cutting tests. The only time shudder and vibration was experienced was when cutting 50mm dia solid mild steel.

BLADE LIFE
This will vary depending on the material cut and method of use, using 210mm dia blade we performed the following:

• 20 cuts through cliplock decking (400mm wide x 45mm high rib x 0.0065mm thick) in comparison a fibre wheel lasted 3 full depth cuts through the cliplock decking material.
• 5 cuts through 50mm x 50mm x 6mm mild steel angle
• 4 cuts through 75mm x 50mm x 6mm rolled hollow section
• 3 cuts through 25mm x 50mm x 3mm rolled hollow section
• 2 cuts through 20mm dia mild steel solid rod
• 5 cuts through 10mm dia mild steel solid rod
• 3 cuts through 50mm x 6mm flat mild steel
• 10 cuts through cliplock decking (400mm wide x 45mm rib x 0.065mm thick)

At the end of this test session the blade was still cutting smoothly and cleanly, the only indication of wear being scuffing on the cutting surfaces of the blade and a small chip off on 1 tooth.

MATERIALS TESTED

• Mild Steel - Tubing (thick and thin wall), RHS (thick and thin wall), Sheet, Flat, Angle, Expanded Metal (heavy section only) etc.
• Roof and Wall Cladding - Corrugated Iron, High Tensile Sheeting (roof and wall)
• Six (6) sheets of corrugated iron together

The thickness of material tested range from 0.35mm sheet to 50mm dia solid steel.

CONCLUSION
These blades surprised the testers with the ease, efficiency and quality with which they cut all the mild steel sections and sheeting materials tested, and received high praises with the comments like amazing, excellent and where are they available from. They also have the advantage of being able to be re-sharpened. It is noted that if users try cutting materials other than mild steel, blade life can be extended. Suitable hearing, eye protection and protective clothing should be used with these blades.