bandSaw mill trouble shooting!

[FJH]

Well men ,Just to up date you guys ,I think the worst is over i hope for now !All of the blades seem to be doing there job now even most of the problem blades!
I upped the the rpms on the wheels 1/3 and am thinking I may do one more pulley change ,and drop from 8.75 to 7.75 pulley to get just a little more out of it Im running approx 830 rpms no load now and a little fluid left to spare (Not MUCH)to run the height control.The drop should enable me to get a decent amount of oil to run the height control no problem , keep the saw at the 4800 to 5000 bfpm and keep the tractor rpms where I'd like em. 12- 1300

Again thanx for the help!
And the input.

Fred

 

[redprospector]

If you're running your blades at 4800 to 5000 sfpm you could up your blade speed some. It depends on your blade size and construction, and wheel size.
If I remember right I'm running mine at about 55 or 5600 sfpm.

Andy

 

[FJH]

If you're running your blades at 4800 to 5000 sfpm you could up your blade speed some. It depends on your blade size and construction, and wheel size.
If I remember right I'm running mine at about 55 or 5600 sfpm.

Andy

Andy

If you go by what Tim wrote in this article

http://www.cookssaw.com/Articles/bandsawturn.php

I,m right in the zone now just want that little bit extra oil for height control! as my head rig lifts by the leftover oil that is not being used to turn the wheels. My wheels are 23.75 inch That means I need aprox 850 - 900 rpm and should @ no load have 1200 just to have that little extra for adjustment.
One thing Tim did not mention was if the speed was in the cut!!?(I asume it is)
I would asume the rpm is going to slow sum in the cut (specialy) in my case using hydralics But even with a motor your going to loose sum!Once I get the new pulley I will take shots on the wheel in the cut and find the sweet spot!

 

[redprospector]

I'd have to check for sure what mine is running. I'm only running 20" wheels with 1 1/2" blades.
My mill is powered by a 1600cc Volkswagon engine so it really doesn't loose much in the cut.
My memory on blade speed could be faulty.

Andy

 

[redprospector]

That's a good article.
I'll have to check some things on my mill and make sure it's about 5500 fps. If I remember right when I built my mill some were saying I could turn it at around 6000 fps.
The only reason I consider wheel size is metal fatigue in the blade. The tighter the radius the faster the fatigue, so in my little mind a little less speed on a smaller wheel = longer blade life (maybe).

Andy

 

[FJH]

Andy heres what Tim had to say about the rise isodent with the new blade!
Also that seemed to heal its self for a time .

Subject: Tims set!


OK Tim !
Did the Cooks set and all seems much better with (new) Blades.
I find the blade tends to limb the first 4 inches into the cut aprox 32 of an inch then finds the sweet spot Any fixes for this ?I'm at aprox 1/6- 1/8 top lead on the wheels now And the rollers are set to the plane of the bed! Should I try and tweak the rollers forward a tad??? Ideas please!!!!

Thanx
Fred

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The Roller guides should always hold the blades straight away , never up nor down.

if the blade wants to climb when entering, I look at 2 things. #1 look at the flatness of the blade. if Too much dish it will climb. if you have the lead on the top of the wheels at 1/16 I would increase if I could to 1/8, but just a tweak will do it.

What the blade is telling you is that the least path of resistance is slightly up. It is not refusing to saw, but it is following the easiest path. When enough change is made to make the path straight away the problem will be gone.

Remember if there is a little too dish in the blade it will rise a little out of the box , but will get better when sharpened. By the 3rd run it could be running at its best.
you might watch this to see if it is a flattness of the blade variation.

1 more thing to watch. if the guide mechanism is flexing when you hit the log this will allow a rise.

As far as the set it seems to be good on the blades.

hope this helps

Tim




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