DoALL Sawing Machines FAQs
DoALL Sawing Machines
Stainless steels may work harden if not machined aggressively. Teeth that rub without cutting can create heat and harden the surface enough to make it impenetrable. Excessive band speed, dull teeth, a blade with too many teeth per inch, and light feed force are among the most common contributors to work hardening.
The band carried those chips out of the work and past a worn, misadjusted, or missing chip brush. Chips that make it past the pile re-enter the work and clog up the tooth gullets, frequently causing tooth stripping.
Adjust the brush to wipe through—but not above—the blade gullets.
Follow the machine manufacturer’s instructions. Band tension stretches the band and keeps it cutting straight despite feed force deflection, but over tensioning causes problems: bands fatigue and break prematurely; band wheels and bearings fail under excessive load, and precise saw head alignments change.
Band saw technicians carry a tensigage (extensometer) to measure band tension. If you suspect your machine is out of calibration and want to schedule service, call (888)362-5572 x 61309.
There are many possible causes. The cure depends on the nature of the problem.
If the saw cuts out-of-square from top to bottom, make sure the saw is level and secure, the loading and discharge conveyors are in the same plane as the vise bed, and that the saw guide inserts, backup bearings, and thumbscrews are in good condition.
If the saw is cutting out of square from side to side, make sure the band wheel and wheel bearings are in good condition. Check whether the saw head is square to the fixed vise, and inspect the head pivot for wear.
If the saw cut is dished, the cause is usually inadequate band tension or excessive feed force. The feed control system may be out of calibration, or perhaps the operator is simply applying too much feed force to a dull blade.
If the problem persists, call SAM at (888)362-5572 x 12024
The band may be tracking heavily against the wheel flanges or saw guide backup bearings due to a misalignment. This can be caused by worn wheel surfaces, wheel bearings, wheel shafts, backup bearings, or backup bearing pivot bolts. If you can’t trace the problem to any of these sources, call for service at (888)362-5572 x 61309.
Yes. It’s better to be safe than sorry. Overnight power surges can destroy invertors and other components. DoALL CPU and pushbutton stations have battery backup to retain memory.
DoALL recommends lowering the saw head at night to relieve pressure on the head lift cylinder seals and packings.
Set the saw guide arms as close to the material as possible. Leave just enough clearance for the vises to open. This minimizes band camber deflection under feed force, and that ensures straight cuts. A small excess in the guide arm spacing has a major effect on blade deflection.
The sawing servo is a hydraulic device that senses and maintains feed force by controlling the travel rate of the saw head. As a result, the saw head travels faster in narrow sections and slower in wider sections. A balance valve performs the same function in newer saws.
Your saw’s model number, serial number, electrical data, schematic numbers, belt numbers and band length are stamped on an escutcheon plate attached somewhere on the machine. This red plate is roughly six inches square. Used machinery dealers commonly remove the escutcheon.
Nothing. The chips actually improve traction, especially when coolants are applied. When you adjust the wheel brush, clear the tire by about 0.005 inch.
Yes. Consult your machine manual for the recommended oil. Oil with the wrong aniline point can destroy seals and create oil leaks. An oil of the wrong viscosity can cause a pressure drop, overheating, leakage, and even cavitation, which can destroy the pump.
Harmonic vibrations can arise at particular combinations of band speed and tooth spacing. Modern variable pitch blades all but eliminate harmonic vibrations, but in some cases you may need to change the band speed slightly.
High pitched vibrations occur when the blade alternates between penetrating the work and skidding across it. To ensure consistent penetration, you can slow the band speed, increase the feed force, replace a dull blade, and select a blade pitch that engages between 6 and 24 teeth.
Low pitched shuddering or bouncing result from overfeeding. The saw needs some combination of faster band speed and lighter feed force. Make sure the blade engages more than six teeth.
Machine sources of vibration include worn or improperly adjusted saw guide inserts, worn band wheel bearings, shafts, backup bearings, or insert adjusting screws. Low band tension or inadequate band preload may contribute.
Saws are designed to shut off under conditions such as a broken or stalled band, an open wheel door, an expired piece counter, or out-of-stock. Any one of those conditions will interrupt the electrical holding circuit and cause the symptom you describe until you rectify the condition.
The most likely causes are excessive band tension or saw head misalignment. If the saw guide inserts and backups are in good condition, schedule a service call at (888)362-5572 x 61309.
- Feed force is the force exerted on a saw blade to cause it to penetrate the work material.
- Feed rate is the resulting lineal speed at which the blade penetrates the material.
- Cutting rate is the area of the cross section the blade cuts in one minute.
In general, the saw cuts more accurately when the guide arms are closer together, so normally you would saw the piece standing up. However, other considerations, including safety, may dictate that you lay the work down and cut it across the wider dimension. In either case, your blade should engage between 6 and 24 teeth.
The transmission linkage may be incorrectly adjusted or worn. A woodruff key or roll pin may be broken. Worn bearings inside the transmission can misalign the input and output shafts, but you won’t know without removing and disassembling the transmission.
If your cut-off saw is cutting crooked, and you suspect the saw guides, remove the inserts and inspect them for obvious damage. For each pair of inserts, invert one of them and press the pair together with the carbide surfaces in contact. If you can feel or hear them rocking, they are worn. If either pair is worn, replace both pairs. To order parts, have your machine model and serial number handy, and then call (888)362-5572 x 12020.
This can occur when the seals wear out and hydraulic oil leaks out of the cylinder. The air causes the bounce as it is compressed under the weight of the saw head. Hydraulic oil needs to be added to the system. Check your saw adjustment summary for the proper procedures.
The manuals for many DoALL machines are available free from the DoALL Sawing Products website. If you don’t find your machine listed, you can order manuals, schematics, and other documentation from (888)362-5572 x 12020. Have your machine model and serial number handy.