Quantcast
  • We invite you to join UKWorkshop.
    Members can turn off viewing Ads!

Baffled by bandsaw

UKworkshop.co.uk

Help Support UKworkshop.co.uk:

sometimewoodworker

Established Member
Joined
4 Dec 2008
Messages
610
Reaction score
57
Location
Watford, Non S-At, Udon Thailand
OK, I tried that. I failed. On the bandsaw, following the table saw kerf on the top of the wood was easy, but after only 70mm or so the blade emerged from the side of the wood at the bottom. I expected the blade to stay within the kerf automatically as it is "easier" than wandering off, but that didn't happen.
Did you kerf both top and bottom?
How deep kerfs did you cut?
How much was left for the band saw to cut?
Is the bandsaw blade correctly tensioned?
Is the bandsaw blade reasonably sharp?
Did you use the bandsaw fence?
Is the material flat and parallel?

At the moment from the limited information I would guess that it could be lack of knowledge causing a possible operator error or an incorrect setup.

The blade staying in the top kerf will be guided by you. The blade pulling out of the side at the bottom suggests one or more of;
only a single kerf,
a blade that is not equally sharp on both sides,
a badly tensioned blade,
possibly blade guides that are loose,
no fence used,
material where the faces are not square to each other,
or attempting to make a seriously large cut.
 

Steve Maskery

Established Member
Joined
26 Apr 2004
Messages
11,791
Reaction score
127
Location
Kirkby-in-Ashfield
Bandsaws are very simple machines. I'm sorry to have to say it but unless there is some sort of mechanical failure, such as a bearing, which you would hear and feel, failings are almost always down to wrong choice of blade or poor machine setup and technique. If the machine is man enough for the job, it should be possible to get it to do it properly. You just have to do the right things in the right order.
 

Just4Fun

Established Member
Joined
21 Sep 2017
Messages
532
Reaction score
36
Location
Finland
Did you kerf both top and bottom?
Yes
How deep kerfs did you cut?
About 50mm deep from each side.
How much was left for the band saw to cut?
About 55mm left in the centre.
Is the bandsaw blade correctly tensioned?
No idea. I have no experience with bandsaws.
Is the bandsaw blade reasonably sharp?
Again, no idea. In my previous session the blade was changed to a new blade so I assume that one was sharp. I don't know what blade was fitted for my latest attempt.
Did you use the bandsaw fence?
There is no fence, so no, I did not use one. I just guided the wood through the saw freehand, keeping the bandsaw blade in the table saw kerf at the top.
Is the material flat and parallel?
Yes.

At the moment from the limited information I would guess that it could be lack of knowledge causing a possible operator error or an incorrect setup.
Yes, it could be either, or a combination of both. Certainly I plead guilty to having a lack of knowledge.
 

Just4Fun

Established Member
Joined
21 Sep 2017
Messages
532
Reaction score
36
Location
Finland
... failings are almost always down to wrong choice of blade or poor machine setup and technique.
Any or all of these could be true.

One issue is that the bandsaw is not mine so I am restricted as to what blade I can fit and how the machine is set up. Also I will never know how it has been set up by the previous user.

One conclusion could be that I should buy a machine of my own so that I eliminate a lot of the unknowns. I assume that a bandsaw capable of resawing 150mm or 200mm wide material is going to be a substantial machine and will probably beyond my budget.
 

Woody2Shoes

Impressive Member
Joined
5 Jan 2015
Messages
1,575
Reaction score
71
Location
Sussex UK
I'd attach the workpiece to a squared-off lump of scrap using DS tape or hot melt glue (to stop it from tending to topple over while 'on edge', and to keep it under control while keeping my fingers attached) and then just freehand cut - following a pencil line along the top of my workpiece. I'd forget fences if they're not working for you.
 

Ttrees

Iroko loco!
Joined
18 Nov 2012
Messages
2,286
Reaction score
72
Location
In me workshop
I think the real question is are you willing to do the work to the machine as seemingly the tutor is not keen on doing the work.?
It could take a few days to sort out.
There is no fence on the machine, why?
Tell us more about if its a new to him machine, or if he has any interest in it running again, might he sell up, or it after all your hard work. etc.

Presuming that all set up was done to the book, suitable tension on a suitable blade for the job at hand, the tutor should have that sorted for you.
I am guessing bad blades or tires that need dressing.
Are you willing to buy blades that might sort things out?
How does the machine run on the wheels (without cutting) with all guides taken out of action well outta the way , are both tires crowned or flat?
You can use a plane iron on its side rigged up with clamps to scrape them, doing freehand will introduce bumps, and freehand might encourage to dress the tires under power, that would be a bit dodgy.
It takes a while dressing, and I'd not want the blisters turning those wheels by hand if there was a chance the machine could be sold on a whim.

Tom
 

hodsdonr

Established Member
Joined
3 May 2017
Messages
34
Reaction score
1
Location
South Africa
An easy way to resaw on a bandsaw without a fence is to mark two lines down the centre about 1, 2 mm apart then saw by eye between the lines. it is a lot easier to keep the blade between the lines than follow a single line and to correct the wander.
 

sometimewoodworker

Established Member
Joined
4 Dec 2008
Messages
610
Reaction score
57
Location
Watford, Non S-At, Udon Thailand
About 55mm left in the centre.
”was the blade correctly tensioned”
No idea. I have no experience with bandsaws.
gives a reasonable idea of what to check and how to check it, all you need is a ruler, you may not be allowed to adjust the tension but you cad certainly check it.

from the information you’ve posted I would say that it’s extremely likely that the fault lies with the; blade or blade’s tension. So most or all of the fault is definitely not with you.

While you may be a novice user it’s clear that the blade can cut through about 105mm as it exited the side of your stock.

The possibility of blade drift is eliminated by the fact that you followed the 50mm kerf and had no fence. The lack of a fence also means that the blade position on the wheels is not important as any drift that a misaligned (on the wheels) blade might have dosen‘t matter as you would be keeping the top line straight guided by the kerf.

I would assume that you kept the workpiece flat on the table and angled the direction of the wood so that the top of the blade stayed in the kerf.
 

sometimewoodworker

Established Member
Joined
4 Dec 2008
Messages
610
Reaction score
57
Location
Watford, Non S-At, Udon Thailand
bandsaw capable of resawing 150mm or 200mm wide material is going to be a substantial machine and will probably beyond my budget.
a 150mm depth of cut is within the capabilities of my elu 3401 bandsaw, they come up used for £100~200 and with a blade fro TuffSaws will do the job.

over 150mm you are looking at double that used and probably about £600+ new.
 

Steve Maskery

Established Member
Joined
26 Apr 2004
Messages
11,791
Reaction score
127
Location
Kirkby-in-Ashfield
Bear in mind that small saws cannot tension wide blades very well, there is not enough rigidity in the frame. The 3401 that STWW mentions above (which was also my first BS - nice little machine, wish I still had it) will do 1/2" max, even though the wheels themselves are considerably wider. OK, you might squeeze 5/8 out of it but I'd be surprised. But it will work sweeter at, say, 3/8". So to resaw with such a narrow blade needs good technique as well as good setup.
 

Sideways

Established Member
Joined
26 Dec 2017
Messages
1,015
Reaction score
41
Location
United Kingdom
Observations from a men's shed:
Everyone used the bandsaw for everything except when they were using the belt sander.
Almost no one had a clue what they were doing but they loved to mess with the setup anyway.
We went through blades like candy.

Bought a bigger machine that wasn't worn out,
Changed the blade to a 20mm one with 3 teeth per inch for ripping,
Taught everyone how to use it before they were allowed on.
Different machine with a different blade for cutting anything but the shallowest curves.
Only two people (who learnt how) were allowed to touch the setup else you buy the replacement blade out of your own pocket
No more logs or pallet wood.
It worked wonders !!!

I would study the Snodgrass video, learn how to set a bandsaw up properly, then assume it is always wrong and you have to check every aspect of the setup / tracking / tension / upper and lower guides before use. It becomes boring but you'll also get quick at it and it's a useful skill to acquire before you buy your own bandsaw.
 

Mcdemon

Established Member
Joined
16 Jun 2019
Messages
19
Reaction score
15
Location
Lincoln
The Snodgrass video is enlightening.
I have the little Record machine and although running ok centring the gullet to the centre of the wheel has turned it into a different machine!
thanks for posting that.....
 

sometimewoodworker

Established Member
Joined
4 Dec 2008
Messages
610
Reaction score
57
Location
Watford, Non S-At, Udon Thailand
Just 1 caveat, the snodgrass setup is correct for the vast majority of bandsaws but not all of them. If your saw is not designed for use with a crowned tyre and has a flat one the positioning on the tyre is different, and the fence, if you use one, setup is different.

My bandsaw has flat tyres. I have used the setup process listed in the manual for all the years I’ve used it, despite the statements of some people here, it works well.
 

ivan

Established Member
Joined
4 Feb 2006
Messages
817
Reaction score
1
Location
Devon
Bandsaw blades seldom cut where you might expect when first fitted. Imagine you have backed off all the guides, and are turning the wheels by hand to track the blade. If the wheels are crowned with a bulge in the centre of the tyre, the angle of the vertical part of the blade will change as the tracking is adjusted. It will probably change as you alter the tension. You can try to set it parallel with the mitre slot. Even if you do carefully adjust, the blade, it may still not cut in line with the bulk of the band as either the set, or sharpness, (even on new) won't be even on both sides. You have to set the fence to whatever angle the blade is cutting at. You check this with a freehand cut along a straight pencil line. Freehand, if the blade was bowing in the cut from top to bottom, either the tension was too low, the blade very blunt, or the feed was too energetic.
 

Steve Maskery

Established Member
Joined
26 Apr 2004
Messages
11,791
Reaction score
127
Location
Kirkby-in-Ashfield
You have to set the fence to whatever angle the blade is cutting at.
I'm afraid I disagree. The tracking knob is there for a reason, it alters the position of the blade on the tyre. Too far back and the blade will be in the 11-5-o'clock direction (looking from above), too far forward and it will be in the 1-7-o'clock direction. Somewhere between the two it will be cutting 12-6-o'clock, parallel with the mitre slots and you will get straight cuts both when ripping and when crosscutting, which you won't get if you skew the fence.
 

clogs

just can't decide
Joined
24 Jul 2020
Messages
401
Reaction score
150
Location
Vamos, Crete, GREECE.......
Just for fun.....
it just takes a while to learn how use all machine......thats why the apprenticship scheme was 5 years long.....
to learn the proper use of a machine requires a good teacher and a machine suited for the job.....
most band-saws work very well.....but like a handsaw/plane.....if u spend a morning just using the thing, altering settings u will find out how to get the best from it......
normally by lunch u've got it down......
bit like a jig saws, they looks easy but does take some skill to get the best out of it......
with the bandsaw in question...try cutting other things like corners and circles....making sure the blade support is lower'd from the re-saw position.......
get a 2x4 and just cut the end off, like square washers.....by the end of the morning u should be able to almost see thru them plus there should be a square end to the stock.....
if u can't do that after a few hours use, dont give up but take a break for a few days and then go back to it......
it is not a race to learn.....!!!!!

hand saw use is also quite a skill but hard work.....spend ur energy doing the fun things...let the machines do the donkey work.....
 
Top