Worth dropping the speed when the going gets tough?

[rsser]

Hi folks,

Have just finished ripping some blackwood, up to 120mm deep, and it's been very slow going even with a sharpened blade. This batch of timber has been the hardest going that I've ever done.

Is it worth dropping the speed? There's a pulley set to halve it for metal. Does the torque increase?

It's Woodfast BS-350 with a claimed 1.5HP.

TIA.

[elanjacobs]

Torque should increase with a slower speed so it's worth a try. What blade are you using?

[rsser]

Thanks. I'll give it a go.

The blade is a bimetal 13mm 3 TPI, with 1 in 5 teeth a raker.

[RETIRED]

Try changing the blade to a 3/8 3 skip tooth.

This is the one we use for all our work and it deep rips 250mm Red Gum boards.

Our bandsaw is only one HP.

The feed rate has a lot o do with it too.

[rsser]

Thanks .

Feed rate was snail's pace. No clogging or binding or burning.

Changing blades on this unit is a royal pain I was hoping to avoid.

[China]

Just out of interest what is the problem with changing the blade I have the larger Woodfast and don't have any problems

[rsser]

Just the time needed to readjust the blade guides and upper wheel.

[vk4]

Are your tyres worn ? this could cause the need to adjust everything when you change Blades.

Jeff

[rsser]

Thanks for the tip Jeff. No, they're good.

It is the case that the wheels are not co-planar and can't be adjusted to be so. But the tracking is OK and that shouldn't affect grunt ... ?

[rsser]

Update:

1. Halved the speed. No improvement with the same batch of Blackwood.

2. That got me thinking. The blade I'm using is not that diff from 's, so what might be robbing my unit of grunt? Allowing for Chinese HP differences ;-)

Blade tension it was. Backed that off a fair way and bingo.

Thanks for your assistance anyway gents.

[tgbrooks]

Ern,

I would have expected it would cut better with a higher tension, not lower. Without a tension meter I thought one adjusted the tension so that a 5 mm sideways movement with a finger tip caused the finger tip to just turn white, or until it just hurt a bit !

On another matter, where did you buy your bi-metal 3tpi blades ? I tried Carbi-Tool in Moorabbin (taken over C&S Saws Mt Waverley) and was told they only have 6tpi minimum and that is for metal .

Trevor

[LGS]

Hi Trevor,

Try here. They come highly recommended.

Regards,

Rob

[rsser]

Proof was in the pudding Trevor.

I mainly do bowl blanks out of green timber where clearly it didn't matter.

The blade came from Henry Bros.

I favour bimetal cos it can be sharpened: less waste; less messing about changing blades.

may weigh in with his Melb. source of preferred blade.

[Durdge39]

I've got the larger Woodfast (the BS-500) and have been using the slower speed setting all the time, whether I'm using the 1"x 1.25tpi ripping blade or the 3/8x10tpi. It seems to cut nicer at a lower speed. As for tension I have started using the flutter method that I read about somewhere long ago. Essentially you run the saw with the guides out of the way and just enough tension on the blade to keep it running on the wheels, and slowly increase tension until the blade ceases to flutter sideways between the two wheels. Seems to work just neato for me.