Thread: Bandsaw woes

Sounds like the motor could be running on just the start winding, not switching over to the main? Centrifugal switch working? (if it has one)


As far as oil goes, the appropriate stuff is apparently something like Mobil SHC 634, which is an ISO460 oil, or alternatively SAE30 oil. That said, I just refilled my BS7, and I had a small amount of Redline gear oil left over, so in it went. Seems a large number of modern gear oils supposedly have no effect on bronze, according to their manufacturers (including the Redline I used). Bronze and gear oils seems to be one of those subjects with a million myths, and very little solid facts to be found. Plenty of discussions on that to be found on Google, up to you to make your own call for that one!

Originally Posted by Jekyll and Hyde

Sounds like the motor could be running on just the start winding, not switching over to the main? Centrifugal switch working? (if it has one)!

No Centf Switch on this one, just a run cap. Will check out the two coils and see what's up.

As far as oil goes, the appropriate stuff is apparently something like Mobil SHC 634, which is an ISO460 oil, or alternatively SAE30 oil. That said, I just refilled my BS7, and I had a small amount of Redline gear oil left over, so in it went. Seems a large number of modern gear oils supposedly have no effect on bronze, according to their manufacturers (including the Redline I used). Bronze and gear oils seems to be one of those subjects with a million myths, and very little solid facts to be found. Plenty of discussions on that to be found on Google, up to you to make your own call for that one!

Thanks

Bob,
I replaced the oil and the cover on my 6x4 BS recently. I replaced the cover with a bit of 5mm acrylic I had. I used diff oil. Now I can see the gears being lubricated and keep an eye on the gears. My original 1/4HP motor got too hot for my liking cutting bigger stuff, so I replaced it several years ago with a spare 1/2Hp motor. MUCH better!

Originally Posted by jhovel

Bob,
I replaced the oil and the cover on my 6x4 BS recently. I replaced the cover with a bit of 5mm acrylic I had. I used diff oil. Now I can see the gears being lubricated and keep an eye on the gears.

Good idea but doesn't the oil just cloud the acrylic?

My original 1/4HP motor got too hot for my liking cutting bigger stuff, so I replaced it several years ago with a spare 1/2Hp motor. MUCH better!

Mine was also getting too hot before these problems - I can't see anything but I suspect the main coils are shot. 1/2Hop replacement sounds like a plan!

The oil seems to run off the acrylic and the gears and oil flow over them remain quite visible.

Well, I stripped the old 1/4HP BS motor down again and had another look at it but couldn't find anything so I decided to give it the flick.
I purchased that BS as a well used unit 3 years ago and it's worked pretty hard since so I cannot complain.

I had a near new 1/2HP SP motor from my small Woodfast lathe (that I converted to a 1HP 3P +VFD) in a cupboard that looked like it would do the job.
- The lathe motor is flange mounted so I had to make a motor foot / flange adapter - I used 5mm steel plate for that.
- Mounting bolt holes in the new adapter were drilled to fit old holes in the BS motor mount plate sot no extra holes in he mount plate which was starting to look like a piece of Swiss cheese.
- 14mm shaft on both old an new motor should have made the pulley change over easy enough but the pulley was rusted onto the old motor so some heat and a big puller were required.

While I was at it I decided to change the oil and add a transparent cover to the gear box.


Electrically the power cord was hard wired inside the motor i.e. no junction box, and just the start/run Cap was located outside the motor housing.
As I had to reverse the motor direction to suit the BS I decided to bring all the motor coil connections back outside the motor and add a junction box which could also contain the cap.
The meant opening up the motor and finding and splitting the run coil/start coil neutral connection and bring these both outside the motor.

The motor is now able to easily be reversed (or converted back the other way if needed) without reopening the motor.


Works a treat.

While I was testing this the coolant lube pump started to leak its contents all over the floor!
So next will be chasing this - it never ends.

Good work there Bob, I hope that you pretty well have it nailed down now, and no more wheels fall off.
Does anyone have an idea how fast you can run these gearboxes? I have a partially completed project BS which was in a pretty bad way, after undergoing an ugly conversion to a wood cutting saw. A 2 pole motor had been substituted, and a different pulleys also. I would like to retain the dual purpose idea, but just do it by reversing the pulleys so as to speed increase for wood, and the normal speed reduction for metal, just wondering if there may be issues of overspeeding the gearbox. The range of speed variation for metal and wood cutting is up to 50:1 for professional cutting equipment, and I am not likely to get any where near this figure, even with a VFD, 3 phase motor and pulley reversal combination, but I do wonder what these worm drive boxes can reliably take. Any thoughts anyone,
Rob.

Thanks RT,

When I first got the BS I did run the BS on the Second Pulley and the gearbox t seemed to work OK but the little 1/4HP motor got really hot. Maybe that's what cause my problem in the first place.

I don't think those saws are designed to run as fast as is need for wood cutting. The Upright MetalFast saw at the mens shed has a 2 x 4 pulley arrangement that enables it to to reach wood cutting speeds if needed but we run it on Lo at belt position 3 - so its the 3rd lowest speed.