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23 records – page 1 of 3.

An experimental investigation into washboarding in bandsaws

https://library.fpinnovations.ca/en/permalink/fpipub37679
Author
Taylor, J.
Hutton, S.G.
White, J.
Date
November 2003
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Society, 35(8), 710-717. Luo, Z., Chen, G, Hutton, S.G., Taylor, J. and White, J., 2001, Experimental
Author
Taylor, J.
Hutton, S.G.
White, J.
Date
November 2003
Material Type
Research report
Physical Description
9 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Band saws
Saw bands
Saws
Bands
Series Number
2144
W-2013
Location
Vancouver, British Columbia
Language
English
Abstract
With the pressures on our industry at this time, sawmills are using thinner saws to try and improve recovery without reducing current production levels. This has led to washboarding becoming a widespread problem in the industry. Washboarding is a wavy pattern that appears on the surface of lumber due to excessive vibration of the sawblade as it cuts through the lumber. In this study the washboarding behaviour of saws was studied at both the analytical and experimental levels to develop a much better understanding of the problem and lead to a set of guidelines for industry use. This was a joint project between Forintek Canada Corp. and The University of British Columbia. Dr. S. G. Hutton led the analytical side of the work and Dr. J. Taylor the experimental portion of the work. This report is a portion of the overall research endeavour and presents the results of the experimental work that was conducted. To compliment and validate the analytical portion of the work a series of cutting tests were conducted to examine the washboarding phenomenon and the factors that influence its occurrence. The effects of wheel rotation speed, strain, tooth bite, and depth of cut were examined and their effects recorded. As small changes in tooth design are known to influence a saws washboarding behaviour, but are not accurately predicted by the mathematical models, we also carried out cutting tests with saws of different thickness and tooth pitch, progressively increasing the length of the tooth face and the depth of the gullet until washboarding on the lumber surface was quite severe. In this manner we hoped to be able to develop some guidelines for the industry. It was apparent from the initial tests that there were two types of washboarding. We have called the larger diagonal waves that often appear with industrial sized bandsaws, Type I. The narrow more vertical pattern or that on circular saws is called Type II. The results in this report are primarily associated with Type I and show the somewhat insensitive nature of the washboarding instability to changes in the operating parameters. The occurrence of washboarding is more sensitive to changes in the tooth geometry.
Saws - Band
Cutting - Tests
Documents
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The automation of bandsaw roll-tensioning. Phase 1. Roll tensioning stresses and performance : final report

https://library.fpinnovations.ca/en/permalink/fpipub1014
Author
Taylor, J.
Hutton, S.G.
Date
July 1990
Edition
37393
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Taylor, J.
Hutton, S.G.
Contributor
BCASI Research and Development Fund.
Date
July 1990
Edition
37393
Material Type
Research report
Physical Description
49 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Band saws
Saw bands
Saws
Bands
Saw mills
Automatic control
Series Number
W-1262
Location
Vancouver, British Columbia
Language
English
Abstract
This report presents the results of the first stage of an investigation into the feasibility of developing a machine capable of automatically tensioning a bandsaw blade. The present work involves an experimental and analytical investigation of the effects of roll tensioning upon the cutting performance of the bandsaw. In order to understand the role of roll tensioning its effects on internal stress distribution, torsional and lateral natural frequencies and stiffness of the blade have been investigated. The results of strain measurements induced during different rolling patterns and with different thickness of plate and differing rolling pressures are presented and an analytical explanation of the results is given. Experimental results showing how the stiffness of the blade and its natural frequencies are affected by the roll tensioning are also presented. An accurate analytical model that relates the rolling pattern to the lateral stiffness has not been found. Cutting tests have been conducted in which the performance of a blade with no tension is compared with a blade with different levels of tensioning. The results of these tests are presented and indicate that the relationship between cutting accuracy and tensioning is very subtle.
Saws - Maintenance
Sawmilling - Automation
Saws - Band
Documents
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Bonding and wear of ceramic saw teeth

https://library.fpinnovations.ca/en/permalink/fpipub1058
Author
White, J.
Taylor, J.
Date
July 1997
Edition
37454
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
White, J.
Taylor, J.
Date
July 1997
Edition
37454
Material Type
Research report
Physical Description
18 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Wear
Saw tooth
Saws
Design
Series Number
Project No. 1008
W-1417
Location
Vancouver, British Columbia
Language
English
Abstract
A report on the results of tests on the feasibility of using ceramics for saw blade tips. The major factors determining whether it is practical to use ceramics are the physical attachment of the tip to the blade, the inherent brittleness of the material and its wear characteristics.
Saws - Tooth design
Cutting edges - Wear
Saws - Tipping
Documents
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A concise review of an experimental investigation into washboarding in bandsaws

https://library.fpinnovations.ca/en/permalink/fpipub37710
Author
Taylor, J.
Hutton, S.G.
White, J.
Date
March 2004
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Taylor, J.
Hutton, S.G.
White, J.
Date
March 2004
Material Type
Research report
Physical Description
12 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Band saws
Saw bands
Saws
Bands
Series Number
2144
W-2080
Location
Vancouver, British Columbia
Language
English
Abstract
In the laboratory testing two distinct washboarding patterns were obtained. They are labeled as Type I and Type II (Figure 1). For bandsaws, Type I washboarding is the one with he washboarding pattern at about 45 degrees. Type II washboarding is usually associated with small bites and the pattern slopes at 20 to 30 degrees from the path of the saw teeth. Although we obtained some data on the Type II washboarding, this report is associated only with Type I, as this is the type most often encountered in the primary sawmilling industry and is of principal concern to Forintek's members. It should be noted that the same two types of washboard exist for circular saws; however, these are not covered here. The effect of the many variables listed above on the range of washboarding in bandsaws has been experimentally examined in some detail. The results are presented in this report along with some guidelines for the elimination of washboarding. Although much valuable data have been obtained during this study, more research is required in order to obtain a complete understanding of washboarding. The recommendations given in this document were found to be effective for 16, 17 and 18 ga. blades on a 5 ft. bandmill, but can be expected to be helpful for other sizes of bandmills also.
Saws - Band
Cutting - Tests
Documents
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Development and mill trials of an active guide system for bandsaws (final report)

https://library.fpinnovations.ca/en/permalink/fpipub37418
Author
Taylor, J.
White, J.
Date
October 1996
Material Type
Research report
Field
Wood Manufacturing & Digitalization
System." Internal Rep., Dept. Of Mech. Eng., Univ. Of British Columbia, Vancouver, Canada. Taylor, J
Author
Taylor, J.
White, J.
Date
October 1996
Material Type
Research report
Physical Description
19 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Stresses
Band saws
Saw bands
Saws
Bands
Blades
Sawing
Series Number
W-1330
Location
Vancouver, British Columbia
Language
English
Abstract
Research into the cutting characteristics of bandsaws has shown that the average cutting path of the sawblade is biased to one side of the ideal cut path. It has also been shown that a strong correlation exists between this cutting bias and sawblade deviation. This report is the second on the topic of bandsaw cutting bias and describes the development and mill trials of a PC based, self aligning bandsaw guide system. This system uses data from the sawblade, and programmable logic controllers controlling the bandmill, to monitor bandsaw cutting behaviour and align the guides to minimize the cutting bias and sawblade deviation. The system is shown to effectively reduce sawblade deviation and unscheduled blade changes and compensate for damaged or poorly prepared blades.
Saws - Band
Sawing - Blades
Cutting - Stresses
Documents
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Dynamic behaviour of saws and sawing systems : cutting characteristics of bandsaws

https://library.fpinnovations.ca/en/permalink/fpipub37194
Author
Taylor, J.
Hutton, S.G.
Date
March 1987
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Taylor, J.
Hutton, S.G.
Date
March 1987
Material Type
Research report
Physical Description
35 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Stresses
Band saws
Saw bands
Saws
Bands
Blades
Sawing
Series Number
CFS No. 42;02-12-15-022
W-491
Location
Vancouver, British Columbia
Language
English
Abstract
Saws - Band
Sawing - Blades
Cutting - Stresses
Documents
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Effect of bandsaw stresses on blade stiffness and cutting accuracy (thesis format)

https://library.fpinnovations.ca/en/permalink/fpipub37321
Author
Taylor, J.
Date
March 1993
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Taylor, J.
Date
March 1993
Material Type
Research report
Physical Description
151p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Band saws
Saw bands
Saws
Bands
Blades
Sawing
Series Number
Forestry Canada No. 52A
Contract no. 1212K032
W-1046
Location
Vancouver, British Columbia
Language
English
Abstract
The effect of bandsaw roll-tensioning and bandmill axial forces on the stresses in the blade, on the interaction of the blade with the bandmill and on the stiffness and cutting accuracy of the sawblade are examined. The stresses due to roll-tensioning are measured and their effect on frequency and stiffness determined. The effect of the blade-wheel geometry on the stresses in the cutting region are analyzed showing how the stresses, frequency and stiffness of the sawblade relate to its cutting accuracy. Empirical relationships are developed that enable the stresses due to roll-tensioning to be estimated. Analytical methods accurately predict the effect of roll-tensioning on blade torsional frequency and lateral stiffness. A model was developed that successfully predicts the effect of overhang on the stress in cutting region of the blade. Both analytical and experimental results confirm that rolling in the centre 60% of the sawblade will increase blade stiffness while rolling outside this region will reduce it. Cutting accuracy is shown to be strongly related to lateral tooth stiffness, and it is also shown that optimum increases in stiffness and improved cutting accuracy are obtained by confining the roll-tensioning to be close to the blade centre-line.
Saws - Band
Sawing - Blades
Documents
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The effect of different amounts of roll-tensioning on the cutting accuracy of bandsaws

https://library.fpinnovations.ca/en/permalink/fpipub5536
Author
Taylor, J.
White, J.
Bouchard, A.
Date
September 1997
Edition
37463
Material Type
Research report
Field
Wood Manufacturing & Digitalization
being accurately leveled and the tension being consistent aroimd the saw. 6 References Taylor, J
Author
Taylor, J.
White, J.
Bouchard, A.
Date
September 1997
Edition
37463
Material Type
Research report
Physical Description
11 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Band saws
Saw bands
Saws
Bands
Blades
Sawing
Series Number
W-1468
Location
Vancouver, British Columbia
Language
English
Abstract
Across North America the amount of tensioning used in bandsaws varies drastically. Sawblades tensioned to fit circle gauges from 28 feet to 80 feet in diameter are in regular use and performing very well. This raises the questions as to what is the right amount of tension and what effect does it have on cutting accuracy. In this study, the cutting accuracy of five sawblades, with varying levels of tension, have been measured and compared. The results show that little change occurs in cutting accuracy once enough tension has been put into the blade for it to fit an 80-ft circle gauge.
Saws - Band
Saws - Maintenance
Sawing - Blades
Documents
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The effect of increasing bandmill speed on vibration and cutting accuracy. Part 1. Laboratory experiments. (Final report).

https://library.fpinnovations.ca/en/permalink/fpipub37351
Author
Taylor, J.
White, J.
Date
February 1994
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Taylor, J.
White, J.
Contributor
Science Council of British Columbia.
Date
February 1994
Material Type
Research report
Physical Description
66 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Band saws
Saw bands
Saws
Bands
Saw mills
Equipment
Sawing
Series Number
W-1134
Location
Vancouver, British Columbia
Language
English
Abstract
This paper investigates the feasibility of increasing bandmill production by proportionally increasing both blade speed and lumber feed speed. A modal analysis of the bandmill and bandsaw was conducted and resonant conditions, likely to impair performance, were identified. Cutting tests were conducted to determine the effect of increased blade speed on cutting accuracy, surface finish and sawdust quality. The tests were conducted at blade speeds of 10,000 fpm, 12,500 fpm and 15,000 fpm and examined the effect of tipped and swaged blades cutting Coastal Hem/Fir and Interior SPF.
Saws - Band
Sawmills - Equipment
Sawing - Cutting speeds
Documents
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The effect of increasing bandmill speed on vibration and cutting accuracy. Part 2. Mill trials. (Final Report)

https://library.fpinnovations.ca/en/permalink/fpipub37376
Author
Taylor, J.
White, J.
Date
March 1995
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Taylor, J.
White, J.
Contributor
Science Council of British Columbia.
Date
March 1995
Material Type
Research report
Physical Description
37 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Band saws
Saw bands
Saws
Bands
Saw mills
Equipment
Sawing
Series Number
W-1200
Location
Vancouver, British Columbia
Language
English
Abstract
The global objective of the project is to investigate the feasibility of increasing bandmill production by proportionately increasing both the blade speed and the lumber feed speed. The objective of this phase of the project is to transfer the results of the laboratory experiments to the sawmill industry. The work described in this report covers the transfer of the technology to two sawmills. The first report has a more detailed introduction to the project and a review of the literature.
Saws - Band
Sawmills - Equipment
Sawing - Cutting speeds
Documents
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23 records – page 1 of 3.