CHJ
Established Member
OK, maybe, moving fence to the opposite side of the blade for a trial cut would prove the point by binding.
Bandsaw..Straight Cutting
- Thread starter SteveF
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Steve Maskery
Established Member
Indeed it would.
S
S
defsdoor
Established Member
Steve - how long is your "Winter Sale" going to be on for ? I'm tempted to buy the full set but can't afford it right now 
Steve Maskery
Established Member
Well I set it up on Monday, and I'll see how it goes. I don't have a particular end date in mind. Feb is always quiet as people are paying off their Christmas credit card bills, which is why I try to tempt them to succumb to my wily charms. I did the same last year and it worked quite well. You are safe for a couple of weeks, at least.
S
S
just an update
fitted a new 5/8 fastcut blade today..i had some 8 x 8 to cut 4' lengthways
i could not get it to cut straight
spent a good hour messing and gave up
it is what i assume u call drift
as soon as i touched timber it turned right and would have gone across 4" by the time i got 8" into cut
fitted a 1\4 blade just so i could get the job done...cut straight ...just took a while
i will play with the fastcut blade when i get some more spare time
i have some more bits to resaw and i am sure it will be the blade for the job
Steve
fitted a new 5/8 fastcut blade today..i had some 8 x 8 to cut 4' lengthways
i could not get it to cut straight
spent a good hour messing and gave up
it is what i assume u call drift
as soon as i touched timber it turned right and would have gone across 4" by the time i got 8" into cut
fitted a 1\4 blade just so i could get the job done...cut straight ...just took a while
i will play with the fastcut blade when i get some more spare time
i have some more bits to resaw and i am sure it will be the blade for the job
Steve
CHJ
Established Member
That sounds more like blade twisting not just tooth set drifting, are you sure your guide supports are not pivoting?
i am sure they was tight
before i fitted the 1\4 blade i undone everything and started from scratch
i will put the fastcut back on tomorrow and see what happens
i am worried about over tension blade...how do u know when to stop tightening ?
Steve
before i fitted the 1\4 blade i undone everything and started from scratch
i will put the fastcut back on tomorrow and see what happens
i am worried about over tension blade...how do u know when to stop tightening ?
Steve
awbawb":2jwdyxpm said:
this latest problem is free hand , timbers too heavy to hope of using a fence
it is as much as i can do to lift them onto edge of table
had to bodge an outfeed up to support timbers
luckily the table had threaded holes on the back edge
Steve
I would like suggest a setup technique
Remove power
Place A good quality blade onto the wheels with the teeth cutting downwards into the table.
Move the upper and lower guides away from the blade.
Place a little tension on the blade, but not too much. Now tilt the upper wheel to the point where the inside edge if the gullets (cut out section of the blade) is riding in the middle of the top wheel. The wheels are crowned, or curved and you are looking to get the tension in the blade transferred to just behind the teeth. If at all in doubt it is better to have the centre of the blade riding in the centre of the wheel. You do not want the teeth riding in the centre the wheel.
Don't worry about what the blade is doing on the bottom wheel, they are designed to be out of alignment.
Now tension up the blade fully. Have a look at the blade from every direction, it should be straight and true running through the table with nothing touching it. If there is anything touching it all other than the two wheels resolve this first.
Now, if you have a modern bandsaw the guides will be bearing based. I believe that the bottom guide is the most important so always work on setting this up first followed by the top guide.
Move the bearing at the back of the blade forward so that is is circa 0.5 mm away from the blade. It must not be touching. Now set the upper guide back bearing. Check the blade from all around. It should remain true and straight, if there is any bow one of the bearings is touching.
Now set the two side bearings. Move them forward so that they are just behind the gullet. If they are any further forward the set of the teeth will interfere with the setup. Move the bearings into the blade such that if a piece of good quality paper is slid between the blade and the bearing the bearing rotates. The bearing must not touch the blade. Check the setting by rotating the blade, if the bearing rotates it's too close. Repeat for both sides on the lower guide and then repeat for the upper guide.
The guides do not position the blade, they are there to 'bump' the blade back into alignment if its forced off line by too much feed pressure. The blade is held square and true by the tension on the blade and where the tension is created on the blade by the wheels. This is why having a good blade is very important, a poorly manufactured blade will never run true.
Check the table is at 90 degrees to the blade, and the fence is true to the table.
If your machine has multiple speeds set it on a wood speed. I have found that you cannot run it too slowly only too quickly. If the blade is running too quickly it will wander and heat up destroying it very rapidly.
The blade should now cut straight and true, if not there is probably something wrong with the wheels and I would call the manufacturer.
Remove power
Place A good quality blade onto the wheels with the teeth cutting downwards into the table.
Move the upper and lower guides away from the blade.
Place a little tension on the blade, but not too much. Now tilt the upper wheel to the point where the inside edge if the gullets (cut out section of the blade) is riding in the middle of the top wheel. The wheels are crowned, or curved and you are looking to get the tension in the blade transferred to just behind the teeth. If at all in doubt it is better to have the centre of the blade riding in the centre of the wheel. You do not want the teeth riding in the centre the wheel.
Don't worry about what the blade is doing on the bottom wheel, they are designed to be out of alignment.
Now tension up the blade fully. Have a look at the blade from every direction, it should be straight and true running through the table with nothing touching it. If there is anything touching it all other than the two wheels resolve this first.
Now, if you have a modern bandsaw the guides will be bearing based. I believe that the bottom guide is the most important so always work on setting this up first followed by the top guide.
Move the bearing at the back of the blade forward so that is is circa 0.5 mm away from the blade. It must not be touching. Now set the upper guide back bearing. Check the blade from all around. It should remain true and straight, if there is any bow one of the bearings is touching.
Now set the two side bearings. Move them forward so that they are just behind the gullet. If they are any further forward the set of the teeth will interfere with the setup. Move the bearings into the blade such that if a piece of good quality paper is slid between the blade and the bearing the bearing rotates. The bearing must not touch the blade. Check the setting by rotating the blade, if the bearing rotates it's too close. Repeat for both sides on the lower guide and then repeat for the upper guide.
The guides do not position the blade, they are there to 'bump' the blade back into alignment if its forced off line by too much feed pressure. The blade is held square and true by the tension on the blade and where the tension is created on the blade by the wheels. This is why having a good blade is very important, a poorly manufactured blade will never run true.
Check the table is at 90 degrees to the blade, and the fence is true to the table.
If your machine has multiple speeds set it on a wood speed. I have found that you cannot run it too slowly only too quickly. If the blade is running too quickly it will wander and heat up destroying it very rapidly.
The blade should now cut straight and true, if not there is probably something wrong with the wheels and I would call the manufacturer.
Tony Spear
Established Member
SteveF":1bk8fka4 said:
From my childhood:
Q : "Grandad - how tightly should I do this up?"
A: "Until just before it breaks"
:lol:
Giff
Established Member
A blade from Tuffsaws is a must but I have also found the Magswitch re-saw guide http://www.rutlands.co.uk/sp+woodworkin ... ch+8110125 to be really useful as it holds the timber against the fence without pinching. I am not sure who else sells them, I think Axminster used to.
rspsteve
Established Member
SteveF":wnx4lmd6 said:
I need to order up some too.
rspsteve":2csrpqnw said:
i emailed Ian
he was very helpful
u will need custom made as blades are 2750mm...not standard
it took 3 days from email until delivery..excellent service
i got 2 of each incase i busted one
Steve
CHJ
Established Member
As for deflection this is my 3/8" sabre cut for what it's worth, that's how I run it. That's a 3mm drill and I can only just touch the blade with the ends of the rule pushing as hard as possible.SteveF":2goq01ge said:
You should have difficulty twisting the blade when pinched between the fingers, difficult to show but this is as much twist as I can force.
Don't know if the above is the accepted wisdom but it works for me and I've not had one of Ian's blades let go prematurely on weld or tooth gullet so far.
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Random Orbital Bob
Established Member
That's an interesting test. I suspect many people under tension their blades for fear of them breaking. Given its the tension that underpins the straight cutting I think a more objective test like that is better than the garbage in the typical manufacturers manual. Mine says you should be able to flex the blade by 1/4" when the guides are 6" above the table using "reasonable Pressure". Excuse me....in this age of fine precision....when did reasonable become a yardstick? What if I've got hands like hams....or like pixies for that matter. So because in your test you're pushing as hard as you can, although still subjective, its more dependable than "reasonable".
When I first setup my bandsaw some years ago now, I ran a test where I did a test cut with none of the guides in place (carefully mind) and with a brand new blade, it still cuts straight as long as you go slowly in relatively small stock. This proved that the tension, tracking, speed and belt tightness were good enough. The guides are important of course, especially as the timber dimensions increase or the wetter it is etc but a decent blade and decent tension are the most important.
When I first setup my bandsaw some years ago now, I ran a test where I did a test cut with none of the guides in place (carefully mind) and with a brand new blade, it still cuts straight as long as you go slowly in relatively small stock. This proved that the tension, tracking, speed and belt tightness were good enough. The guides are important of course, especially as the timber dimensions increase or the wetter it is etc but a decent blade and decent tension are the most important.
Rhossydd
Established Member
But it still remains a vague measure. There's a lot of advice about bandsaw set up across the web, but it nearly all fails when it comes to this issue as it's so subjective.Random Orbital Bob":4s8jl0cd said:
John15
Established Member
Yes, it's a strange test for a cutting machine - not very scientific but by enlarge it seems to work. It's similar to the test we use to check a bicycle tyre - 'there should only be a slight indentation when applying reasonable pressure with the thumb!'
John
John
Random Orbital Bob
Established Member
Aye.....I spose its because other than invest in very expensive industrial measurement equipment there is no alternative.
