4x6 Metal Bandsaw Mods

[panofish]

A few simple mods really improve a chinese bandsaw.

http://www.youtube.com/watch?v=pUsMVYyHWPc

[BobL]

A few simple mods really improve a chinese bandsaw.

http://www.youtube.com/watch?v=pUsMVYyHWPc

I realise this might sound somewhat cynical but find it hard to believe someone bothered to make a video of fitting a wooden base and changing the legs and bandsaw gear box oil and to then call this a way to tune up a chinese bandsaw. I was expecting to see something more significant like fitting ceramic blade guides or adding a coolant tank or something of a worthwhile nature.

[outback]

Have you seen this?


see it run

These 4 x 6 saws are famous for the saw blade jumping off the pulleys. There are several reasons for the blade doing this. However, I mounted
an aluminum plate to the frame to prevent the blade from jumping off the drive pulley. Works great and it has been on the saw for 12 years. One screw needs to be removed when replacing saw blades. I never thought this saw would last as long as it has.
I have a new saw still in the box for a backup but have yet to open the box.

Jim

[sasquatch]

I've never heard much about the blades jumping off these saws, i suspect there has to be something causing this with your'e saw other than these saws are prone to this.

I been using mine for over 10 years, never had a blade jump off.

[Ries]

I have had 4 of these saws since 1978, completely wore out two of em, two still work every day in the shop.
And yes, the blades do jump off.
The ability to adjust the upper wheel for in and out and for angle is very primitive in these saws, and the blade tension is usually quite hard to get tight enough, so if the upper wheel even gets a bit out of whack, the blades will jump, especially when they get dull.

I like Jim's aluminum plate mod- looks like it would work well for this problem.

The best "mod" I have found is to buy a good one in the first place- I buy the Jet saws, which cost a bit more, and usually run straight and true right out of the box, have better quality castings, more meat to em, and just generally are better made.

There is a myth that these all come out of one factory- in reality, the older ones came from 4 or 5 Taiwanese foundries, and were assembled by a couple of dozen small shops- and now that they mostly come from China, there are at least twice as many foundries and twice as many companies making em.
And they do, indeed, vary a lot- I have seen the same nominal size saw with a cast iron top bow that ranged in size and weight by as much as 30%, and I have seen some with no bearings at all, some that will never cut straight at all.

I run mine mostly on stainless, and I have cut literally hundreds of thousands of pieces on em. I consider em to be basically consumable tools- for $250 to $500, they are about the cost of a coolant pump on a real bandsaw, and considering how cheap and flimsy they are, and yet how well they work, they are one of the single best deals in metalworking tools.

Current prices on quality bandsaws start at well over three grand, and can rapidly escalate from there- I dont think the tiniest Amada saw is under $15k. So for a few hundred bucks, the utility is amazing.

I find the single best thing you can do for these is buy a good bimetal blade. A Starrett or Morse or Lenox will improve the performance a lot. I run bigger, higher horsepower aftermarket motors on mine, too- Grizzly sells 3/4hp and 1 Hp motors that bolt right on. If you let the saws run unattended a lot, as I have over the years, sooner or later you will burn a motor, when the blade jams, and the motor cant turn. At that point, upgrade to more horsepower. Some of the really cheap chinese ones come with 1/3hp motors, and even their 1/2hp motors are generously rated, to say the least.

(I still have a couple of the Jet's in the shed for parts- the first one is so old that it was green, the second one, of about 1995 vintage, is gray- all the newer ones are white)

[sasquatch]

The saw i have is an old taiwan built one, it was old and used when i got it in a trade over 10 years ago. Only thing i did other than line it up etc was to change to a Canadian built motor.

These saws are one heck of a great deal, for a shop, but as posted above i see some real flimsy looking new ones at times, they're getting cheap in quality trying to compete.

[BobL]

Have you seen this?
.
.

Now that is what I call a tune up.

These little saws are amazing. Last night mine made a 220 mm cut in a 16 mm thick piece of steel, It took about 15 minutes but it did it.

[Rex]

+1 on the Jet saws. I used a HF for years, workd fine, but took care to move it around lest the legs collapse! The Jet is so much nicer, the material is heavier, it just works better. I have since scored a Marvel 612, but the Jet is a keeper.

[Boucher]

My blade frequently jumps off and it is a PITA. Will try the plate to improve.

A good improvment project for the 4X6 is shown here.
http://www.homemetalshopclub.org/pro.../sawstand.html

[lynnl]

I realise this might sound somewhat cynical but find it hard to believe someone bothered to make a video of fitting a wooden base and changing the legs and bandsaw gear box oil and to then call this a way to tune up a chinese bandsaw. I was expecting to see something more significant like fitting ceramic blade guides or adding a coolant tank or something of a worthwhile nature.

I didn't watch the video BobL, but I know where you're coming from.

I'm amazed at some of the drivel people will bother with putting on a video.

"....hi folks, Marty here. Today I'm going to show you how to open a new box of breakfast cereal...."

[DICKEYBIRD]

Shoot, I wish someone'd show me how to open the plastic inner bag in a cereal box. The stupid manufacturer's turn up their RF sealer machines so high the bags are permanently welded together and won't split apart neatly like they used to.

[lynnl]

Shoot, I wish someone'd show me how to open the plastic inner bag in a cereal box. The stupid manufacturer's turn up their RF sealer machines so high the bags are permanently welded together and won't split apart neatly like they used to.

Well, that's true too, Dickeybird.

I guess I picked a bad example.

[outback]

The reason the saw blade jump off the drive wheel is the blade hits a snag in the saw kerf and stops the blade. The drive wheel keeps on turning against a blade that won't move and in a couple of turns of the wheel the blade works
its way off the drive wheel. This is why my plate works.

Another thing I have noticed when sawing near the end of a cut is the cut piece can swing upward and work just like a disk brake caliper, pinching the blade and stop it cold in its tracks. Usually the saw swarf under the stock makes it work like a disk brake. Keep the cutting area clean seems to reduce problems.

The problem with my "Saw blade retaining block" is when the blade snags and stops moving sometimes the drivewheel also stops leaving slippage in one area??? The drive belt!!!!! I have completely burned up the plastic belt guard and 2 drive belts because the blade snagged I the saw was running and I was not around the stop the saw. Scary because the shop fills up with smoke.

Bi-metal blade are the only way to go. I gave away some new flex back blades to my bro-in-law. I figure the flex back blades are not worth the time
to install.

Oops,,,by the way, my 4 X 6 saw is running. I better go check!!!!

Okay this time but this is what I find sometimes!!!



Jim

[panofish]

I realise this might sound somewhat cynical but find it hard to believe someone bothered to make a video of fitting a wooden base and changing the legs and bandsaw gear box oil and to then call this a way to tune up a chinese bandsaw. I was expecting to see something more significant like fitting ceramic blade guides or adding a coolant tank or something of a worthwhile nature.

Please realize that there are many levels of experience.
I do appreciate that many on this forum have much more experience than me. I only wished to share what I had done with anyone else that might find it useful.

[Rex]

Please realize that there are many levels of experience.
I do appreciate that many on this forum have much more experience than me. I only wished to share what I had done with anyone else that might find it useful.

Thanks for sharing, you opened up a good discussion.
I bet most of us did not realize you were posting your own work, as opposed to an anonymous website.