MECHANICAL GRADING OF SMALL DIAMETER LOGS Team Flex

MECHANICAL GRADING OF SMALL DIAMETER LOGS Team Flex. Grade

Background � � There is a potential market for the use of small diameter logs as integral parts of a structure. Current grading techniques are conservative and unreliable. Six-inch-diameter lodgepole pine used in 5, 000 ft 2 library in Darby, Montana.

Current Methods of Grading � Visual Grading- Certified Graders measure: � Knot size � Knot type � Slope of grain � Major Defects or inconsistencies

Problem Statement � The objective of this project is to design and build a test rig that is inexpensive and portable; which can grade the strength of small round timbers quickly and accurately, requiring minimal user input.

Current Mechanical Grading Apparatus

Specifications � � � � Inexpensive- Less than $7, 000 Adjustable- Accommodates 3 -9 in. logs and spans a length to diameter ratio of 21: 1 Durable- Can withstand travel and everyday use. Reliable- Gives accurate results with minimal upkeep. Portable- Towable by small pickups to different job sites. Fast- Must be able to keep up with pace of mill. Minimal User Inputs- 4 -5 manual inputs per test. Safe for operators

Design � Major Components � Trailer and Supports � Loading Arm � Deflection and Load Measurement � Hydraulics � Controls

Trailer & Supports I-Beam 10 X 25. 4 Supports 2000 pound rated axle Mount for load arm

Supports Base Plate

Load Arm and Hydraulics 2000 PSI Rated Hydraulic Cylinder Powered by ½ HP Hydraulic Pump Load Arm I-Beam 6 X 12. 5 Load Head & Protective Covering Guide for Cylinder

Load Cell and Deflection Measurement Ultra-Sonic Transducer Load Cell

Data Acquisition � Acquiring Data � National Instruments DAQ � Measurement Studio � Interpreting Data � Filtering out bad data � Fluctuating data points � Calculations � Modulus � of Elasticity Recording Data � CSV format

Software Goal: Automate many of the processes required to determine the grade of a log and record the results. Specifications: � No hassle – Few number of clicks to grade a log � Easy to Use – Requires little to no training � Practical records – Data readable by Excel

Testing Results � Preliminary tests show that our calculated Modulus of Elasticity of a steel bar is within 5% of accepted value of steel � In the following weeks we will test our machine against the laboratory setup.

Recommendations � Design Supports for 2 degrees of freedom � Allow motion perpendicular to I-Beam � Rotatable support � � Compare our machine to the apparatus already in lab Get the machine in the field

Completed Trailer