Cheap Chinese bandsaw issues etc.

[Flynth]

I have a cheap Chinese bandsaw that looks like this:


My first issue with it is that at the time I bought it there was no model with built in cooling so my unit has no cooling whatsoever :-(

When cutting I've been giving it a squirt of coolant from time to time, for long cuts I've rigged a piece of tube filled with oil plugged with a cotton bud that allows oil to drop slowly onto the cut. However, I found oil is not very good for it, it contaminates the drive wheels and the blade doesn't grip as hard. It is very easy to stall after oil was used.

So my first question is about cutting steel with no coolant. How much less of saw life I can expect when cutting with no, or occasional coolant? Is coolant really necessary when cutting thick solid rods with such saw? I use m42 bimetal saws.

Second question is sort of related to the first. Because the saw would stall I had to set very slow down feed when cutting a particularly large piece. Unfortunately twice during the cut the down feed just stopped! I had to crack the valve open and close it again to get it going again. I bought the saw 4 years ago. Do I need to change the oil on the down feed cylinder? Or perhaps does it need a clean?

In general I would be quite happy with this saw if I managed to resolve that downfeed issue. I have some huge blocks of metal to cut, basically at the limit of the machine, but if the feed just stops on its own its going to be very annoying coming half an hour later seeing it hasn't moved.

Finally, does anyone have a good method for setting the saw guide rollers? They are kept and swivel on a single m8 bolt. There is no reference surface to set them to. It seems the only way is to adjust, then cut and see if it cuts crooked. If it does adjust a tiny bit by loosening the bolt and tapping, then cut again. Does anyone know a betteer method?

 

[ddillman]

I have a portable handheld bandsaw and only cut dry. The blades last a long time cutting dry.

 

[tq60]

Buy good blades.

Let the saw do the work.

These cut slow so they do not build up much heat.

Hood blade at slow speed will last long time.

If cutting something harder, some oil from a squirter can help.

Sent from my SM-G781V using Tapatalk

 

[MrWhoopee]

It's hard to quantify the difference in blade life unless you are doing production sawing. For most of us hobbyists, coolant is just a pain in the a** and not worth the hassle. There is not much heat generated when band-sawing due to the short time in the cut and long time out. Some people will use a drip or squirt bottle of coolant, but if you've ever dealt with a pump and tank of coolant, you will avoid it if at all possible. I don't miss coming home smelling of rancid coolant. My wife doesn't miss it either.

 

[Flynth]

I have a portable handheld bandsaw and only cut dry. The blades last a long time cutting dry.

Buy good blades.

Let the saw do the work.

These cut slow so they do not build up much heat.

Hood blade at slow speed will last long time.

If cutting something harder, some oil from a squirter can help.

Sent from my SM-G781V using Tapatalk

It's hard to quantify the difference in blade life unless you are doing production sawing. For most of us hobbyists, coolant is just a pain in the a** and not worth the hassle. There is not much heat generated when band-sawing due to the short time in the cut and long time out. Some people will use a drip or squirt bottle of coolant, but if you've ever dealt with a pump and tank of coolant, you will avoid it if at all possible. I don't miss coming home smelling of rancid coolant. My wife doesn't miss it either.

Thank you. The saw has 3 speeds. The manual said (If I remember correctly) to use the middle speed for steel (28m/min or 84sfpm). The lower speed is 19m/min (57sfpm). Top speed is 50m/min(150sfpm).

I cut mild steel at middle speed, tool steel (o1 - in soft state) on slowest and aluminium on highest.

Do those of you that cut dry do the same? Or do you cut mild steel on the slowest setting?

 

[mikey]

Try a wax stick lubricant. Blades cut well and can last for years with that stuff, especially in a hobby shop. Plus, no mess to clean up.

 

[jbaccell]

Try a wax stick lubricant. Blades cut well and can last for years with that stuff, especially in a hobby shop. Plus, no mess to clean up.

That's what I use on my horizontal bandsaw, wax that comes in a tube/stick. Works well...

 

[Flynth]

Try a wax stick lubricant. Blades cut well and can last for years with that stuff, especially in a hobby shop. Plus, no mess to clean up.

That's what I use on my horizontal bandsaw, wax that comes in a tube/stick. Works well...

Great, I'll do that. BTW, it seems the coarsest blade for this saw width is 6 tpi. That is supposedly good for up to 60mm rod. Those saws are sold as "capacity up to 150mm round". So how do people cut such thick materials?

The manual says for such material one is supposed to use "vario 2/3" blades, but these don't exist! (at least here in EU).

So, how do people cut thick bar with it? Grind every second tooth for more chip clearance?

 

[rodm1]

I have the same down feed I just set it to a good feed and leave it. Works good that way but part setup is a pita. Try a 14 tooth blade and see how that works.

The rollers adjust them after the blade is full installed they should just touch the blade or small gap.

 

[Flynth]

I have the same down feed I just set it to a good feed and leave it. Works good that way but part setup is a pita. Try a 14 tooth blade and see how that works.

The rollers adjust them after the blade is full installed they should just touch the blade or small gap.

It used to be like it, that I could set it and leave it. Now however, occasionally (every 15min?) down feed will just stop until I fiddle with it. I thought of starting this thread in hope someone has this problem before and knows what caused it. Those saws are pretty popular all over.

14tpi? For thick solid bar? That's a big "no no" isn't it? If 6 TPI is supposed to be too coarse 14 TPI is going to jam very quickly unless you set the down feed really slow.

I have a circular metal cutting saw. (so called dry/cool cutting). I use it all the time for thin wall profiles and solid bars for up to 2 in in diameter. So all I really need the bandsaw for is material over 2in. Most often over 4 in at the capacity limits of the saw.