I need to cut 1/2"

Thicker metal shows greater blade / saw adjustment errors. A simple 1/64 or 1/32 wont show much on an 1/8 thick piece of metal when cut.
Those numbers will double quickly as the cutting blade travels through thick metal.
Metal band saws seem to be trickier to adjust and fine tune because the blade seems to be twisted into the roller guides.
The downloaded manual for the saw that looked most like mine at grizzly.com helped my adjustments a lot.
The saw quality is also a factor.

You need to measure the outside diameter of the pipe then go to your hardware store and buy a flexible coupling of that size.

Buy a small piece of chicken wire.
One additional piece of PVC pipe, and a coupling.

Cut the chicken wire the exact size of the outside diamiter of the pipe, place it on the end of the pipe and install the coupling over it.

The chicken wire "screen" will be help in place by the pipe wall, the internal ring on the coupling, and the PVC glue. Cut the pipe to the length you need and install it on the intake pipe outside the wall.

use a small tube cuter. / pipe cutter

Normally blade overheating. Improper blade or too few teeth for material, teeth not sharp and/or offset enough for proper width of cut. Teeth must cut wider than blade. Inexpensive blades tend to do this quickly. Other possibility: Bad bearing, check for play with saw unplugged. Blade should have little wobble. Other possibility: Saw body cracked/damaged(allowing shaft to skew) or very cheap saw unable to handle material

if the drain is slow or stopped up, i use a high powered drain opener from ace hardware called "liquid fire" it is different from drano and all that other ****.

eyohe

Please read and understand these entire posts and collect all tools & materials before beginning this project.
 
Materials needed:
 
2 - PVC 1-1/2" compression x 1-1/2" female Schedule 40 solvent        weld trap adapters.
 
2 - 1 1/2"PVC-DWV ADJ P- traps (serviceable)
 
1 - PVC 1 1/2 X 1 1/2 X 1 1/2 sanitary Tee 
 
1 - 90 degree PVC short turn elbow 
 
1 - 4' piece of 1 1/2 PVC sched. 40 pipe
 
1 - 4oz can Oatey PVC Regular Clear Advanced Cement
 
1 - 4oz can Oatey PVC Clear Primer
 
1 - Small container plumbers putty (To be used as a gasket like bushing between the disposers basket strainer and the sinks surface)
 
Tools that are needed:
 
Safety glasses
Latex gloves
Hacksaw
Torpedo level
Measuring tape
Channel locking pliers
Sharpie type pen/marker
Old work rags to clean the edges of freshly cut PVC pipe of loose debris.
Old newspaper to protect your floor/work area and the floor of the sink base.
Any other tools listed with the disposal installation instructions.
       

I worked at a tool rental business while going to college and became familiar with OSHA requirements as it pertains to construction. There is an old saying that if you follow the rule-book by the letter things will quickly come to a grinding halt. I checked on OSHA web site and could not find anything on you question. I recall that using the correct blade only results in a cleaner cut, however there is the possibility that the pvc material can load-up on the blade and cause jambing. An inspection of the blade will answer this. More important is that all safety items are in place like the blade guard and that all workers in the vicinity of the saw are wearing eye protection. We used Norton brand abrasive blades and the following is their guide. APPLICATION GUIDE:
Concrete: For concrete/masonry - silicon carbide specification for brick, block, concrete, and other masonry materials.
Metal: For metal/steel - aluminum oxide specification for mild steel, stainless, and metal decking.
Asphalt: For use when cutting mostly asphalt.
Asphalt / Green Concrete: For asphalt and green concrete - silicon carbide in coarse grit range. For high performance, hot pressed wheels provide significantly longer life.
Ductile: For ductile iron and cast iron pipe - formulated with a special blend of silicon carbide (for cutting) and aluminum oxide (for long life). This specification is also suitable for cutting PVC.

Hope this helps, enjoy

remember to match the blade width to the type of cutting you are doing. Also keep in mind: * Narrow Blades can make much tighter radius cuts, but tend to twist and wander when making long straight cuts. * Wide Blades can't make the tight turns that narrow ones can, but they hold a straighter line than their narrow counterparts. * The tpi determines the speed with which the blade cuts through stock. Blades with high tpi cut slower but leave a very smooth edge. They are best for detail work on thin stock. Blades with low tpi cut quickly and leave a slightly rough edge. They are great for resawing or long rip cuts. * Steel Blades are inexpensive and work well for cutting softwood. Steel blades, however, dull quickly in hardwood. * Bimetal Blades are made of high-speed steel and can cut thin metal or wood. * Carbide Blades are for wood cutting only. They are more expensive than other blades but stay sharper longer than steel or high-speed steel.

blades are available for different applications. A few common blades include:Steel Blades are inexpensive and work well for cutting softwood. Steel blades dull quickly in hardwood. High-Speed Steel Blades are harder than steel blades and stay sharp longer. Carbide-Tipped Blades are more expensive than other blades, but they stay sharp much longer than steel or high-speed steel.