Archive:Equipment/VerticalBandsaw

About

There is now a vertical bandsaw in the space.

The is the machine which is green on one side and black on the other.

This machine is dangerous .. even more dangerous than the other machines. And they're not pussycats - they can all kill you, some more quickly than others. This particular one likes to cut bits off you in a blink, then leave you to bleed to death but if sufficiently abused it can come up with more creative methods.

It's a nu-tool HBS10 10" bandsaw. Probably a Chinese import rebadged by Nutool.

Status

This bandsaw is working. Phil and AJP think it is in good adjustment as of 1st april 2011. It makes a click every time the weld in the blade passes through the business end without a workpiece pressed against the saw, it's just the blade touching the upper bearing, we don't think the blade is touching anything it should not.

The current blade is usable but not brilliant for the 5mm wood sheet that is used in the laser cutter. You have to cut really slowly or the blade may bind up. It's not good for wood any bigger than that. A label saying "warning 5mm thick sheet max" would be good with the current blade--AJP

The saw is set up with a fairly fine blade (24 tpi) suitable for metal sheet, plastics or PCB material. The slowest cutting speed is recommended for use with this blade : do not speed it up. It will cut wood, but will be tediously slow. I do have blades suitable for cutting thicker wood but they're a lot more dangerous - I'm going to see how many fingers are lost to this one before I fit those.

I have a couple of spare wood-cutting blades available, but it might be better to stick to metal-cutting blades as fitted previously. If you use the saw, please let me know what for so we can choose something suitable. Artag, 27.3.11

There is a 14tpi (teeth per inch) HSS blade and a 10tpi carbon steel blade in brown cardboard cartons in the corner of the room behind the powertool shelves.

I'd like to put the 14tpi blade in and see if it's a decent compromise for PCB's, lasercutter ply and small blocks of wood. --Ajp
Go for it --Artag.

How to use

tl;dr summary:

• It's intended for light duty work - cutting PCBs, sheet aluminium, small pieces of wood, plastics etc. It's NOT for cutting up hunks of metal for the lathe or welder or staircase-sized chunks of timber.

• Be careful of your fingers

• If the blade isn't running correctly in the guides (or you don't know what that means) don't use it.

It's also potentially a great deal more dangerous than the horizontal bandsaw due to higher speeds and the need to put your fingers close to the blade, so don't use it unless you know exactly what you're doing (this particularly applies to the wood blade which may not be fitted, but that doesn't mean the slower, smaller-toothed metal blade is harmless).

If you're just too lazy to get a handsaw and think you'll use a power saw to save a bit of elbow grease, make sure you have more fingers than you really need as you're going to lose some. Can't-be-bothered is not compatible with take-care.

The instructions for use are here. READ THEM.

Two points as mentioned above are especially important :

• To protect your fingers, keep them away from the blade. Ideally, push material through the saw by holding it against the guide and sliding the guide. This keeps the material rigid and your fingers on a known path. If this isn't feasible, hold the material with two hands, so that the cut is going down the middle. This will help avoid any sudden catches which might grab the material and pull your fingers into the path of the blade.

• To protect the bandsaw from damage, it's essential that the blade runs in the guides. This stops it sawing itself to bits, which is what happened to the horizontal bandsaw and why it isn't used much any more. The main way you can tell that it's working correctly is to watch the point where the blade runs through a guide just above the cutting point. It should be not-quite-touching the bearing that's positioned behind it (pictures are in the instructions referenced above). Under cutting pressure, the back of the blade will touch this bearing. If it's anywhere else, it's probably running the teeth against some part of the saw, perhaps under the cover where you can't see it. So stop, because that will ruin it.

Although the blade seemed to be running fine last time I looked, there may be wear, the effect of tough sawing, mindless fiddling or some other reason why it's working one day and not the next - so watch it carefully and don't just keep it making some horrible noise until it's dead.

DO NOT adjust the screws on the top or side unless you understand what they do and how fussy they are on a light duty machine like this. They adjust the blade tension and tracking. It takes a long time to set them correctly and if they're mis-set the blade will wander off the pulleys and ruin the saw, your work, and you. So leave them alone and if it's not working properly, note it on the mailing list.

It's a bit of a fiddly job to get it running smoothly in the guides so don't attempt to change it unless you're prepared to spend a long time messing. Fully read procedure below and instruction leaflet. If you feel you must, and it ends up working less well than when you started, label it and mention it on the mailing list. Better to admit you need more practice than wreck it for the next person.

--Artag 22:55, 17 February 2011 (UTC)

As best as I can measure it the blade is 50 and one eighth of an inch (127.4cm) in circumference. It is 3/8 of a inch wide (9mm) to the points of the teeth. Seems to be an unusually small size. A custom made blade of 50" length and 3/8 width seems ok so far. There seems to be three standard blade widths. I think a blade other than 3/8" wide is probably a bad idea. Ajp

Notes on alignment and fitting a new blade.

We found that the upper pulley wheel bearing was not tightly screwed to the vertical bit of metal that goes against the side of the machine. There is a slot for a flat screwdriver in the middle. Tightening this up seemed to make it a lot less temperamental to adjust.

Blade Installation Procedure

Phil and I set it up with a new blade (ok Phil took charge of the tricky bits). The procedure we used was more or less as follows.

1. Do not touch the innards unless it is unplugged.
2. Get someone who has machine tool experience to help, do not proceed otherwise.
3. Do not power on unless you can carefully check nothing is fouling by rotating the drive pulley by hand. Mark it out of order and leave it if you can't make it run freely.
4. Have a clear, well lit work area so you don't loose any of the small parts.
5. Remove cover, put thumbscrews they won't get lost
6. Use a large flathead screwdriver to check the upper pulley bearing is screwed down tight
7. Remove the wing-nut, washer and bolt on the edge of the tray(the flat bit you put the work piece on).
8. Remove silver guard(loosen two black screws) then the whole tray.
9. Remove the upper guide
10. Remove the lower guide by removing the single screw, not the two vertical position screw.
11. Slacken the middle side knob.
12. Undo the top tensioner knob until you can easily get the blade over the top pulley wheel.
13. Put the blade in. Flat side on right, teeth on the left looking at the front of the machine.
14. Get the blade central on the pulleys.
15. Tighten top knob so the blade has enough tension not to foul inside the machine.
16. Tighten the middle side knob but leave it slack enough for the upper pulley wheel to move a little.
17. Find the right allen key for the grub screw next to the middle knob.
18. Rotate blade by turning the drive pulley by hand.
19. Adjust blade tension by tuning top knob so the blade is straight where it is not on the pulleys. The blade tension needs to be quite high to keep it straight, the top knob needs to be fairly tight.
20. Rotate by hand, tighten middle knob a little if necessary.
21. If really sure, plug in, be ready to switch off quickly.
22. Run the machine watching the blade position on the top pulley and where it enters the machine at the bottom. Switch off IMMEDIATELY if the blade is moving towards the edge of the pulley or fouling elsewhere. Listen and watch closely.
23. Using the allen key, adjust the grub screw and the middle knob very gingerly so the blade runs in the middle of the pulleys. They interact somewhat.
24. The middle knob should be fairly tight but probably not screwed in a tight as it can go. The middle knob should NOT be loose.
25. Check top knob is tight, about as tight as you can turn it with one hand. When confident blade is running OK on pulleys and is suitably tensioned unplug machine.
26. Attach lower runner (leave the little black guard for now). Adjust left/right position so back of the blade is a micron off the bearing. Don't mess with the vertical position.
27. Adjust the metal pegs that the blade runs between so it is a close as possible but has a tiny gap )either side.
28. Attach black guard and fiddle to get the runner right again.
29. Attach upper runner. Adjust the metal pegs.
30. Rotate blade by hand watching the blade at all points.
31. Check black screws are tight.
32. Cautiously run machine.
33. Unplug machine.
34. Reinstall tray.
35. Reinstall silver guard (the bit with the 2 U shaped holes on the edge goes under two black screws).
36. Reinstall bolt washer and wing nut on edge of tray (wing-nut on the underside).
37. Put side cover on (three black thumb wheels)
38. Put allen key back in box.
39. Try cutting suitable materials.
40. Update warning labels
41. Count fingers.

(maybe this procedure should be a separate page)