What factors govern the wander and twist of a bandsaw blade?

I rarely use a bandsaw, probably because I'm so bad with it. I have an old 14" Delta.
I can't get long, smooth curves. My blade always wanders more than I wish it would.
When I tighten the blade, I strum the blade and stop tightening when I hear the first musical note. I recently tightened it up much beyond that, but it didn't seem to make a difference.
I also replaced the upper guides with a new stone set.
When I try cutting circles and such, the blade twists. Is this an issue about blade thickness? How wide does a blade have to be to be stable?
(One thing I'm trying to do is doubleface tape two different wood blanks together, cut a long S through them, and reglue opposing pieces to make two tone cutting boards. I know I need to insert thin flexible shim strips in the glue up to compensate for the kerf.)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
In article

I'm guessing your blade is too wide for the radius of the curve you're trying to cut, so the back of the blade is rubbing on the side of the cut. What blade are you using?
Also, try taking a stone and rounding the back of the blade slightly so the back edges won't grab the sides of the cut as readily.
Oh, and make sure you drop the upper guide to just above the piece you're cutting to reduce blade flex.
You may want to pick up Mark Duginske's bandsaw book. It's very good and will probably provide a bunch of "Aha!" moments.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Lazlo wrote:

Wide? For curves you want a _narrow_ blade. The first hit I found with a table of width vs curve radius is http://www.furniturecebu.com/backoffice/catalogs/_uploads/f_20060607-060424_Vol.23May2006.pdf .
--
--
--John
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sat, 03 Jan 2009 07:36:45 -0800, Lazlo wrote:

All bandsaw blades have a drift angle.
When making the blades, the teeth are set left and right. Usually one side of teeth will end up with a sharper grind or further set away from the blade body. (More expensive blades have a much smaller drift angle, and could actually be not noticeable, you get what you pay for.)
As you manually feed the wood into the bandsaw blade, you need to be aware of the drift angle of that blade and compensate your feeding to match that drift angle.
For my 1/8 inch blade, the drift angle is about 8 to 10 degrees. As I feed the wood into the blade, the pattern line on the wood is not feed directly straight in-line to the blade, I swing the wood to my left 10 degrees and sort of feed the line sort of side-wise into the teeth at about 10 degrees.
Gosh, that's about as clear as mud. Much easier to show you than type it out. Maybe someone else who is a better wordsmith can explain better.
Note: high end bandsaw fences have elaborate blade drift micro- adjustments. This dramatically improves the rough kerf sidewalls that bandsaws are so notorious for.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Phil Again wrote: (snip)

What you need is a video, so here you go:

http://www.youtube.com/watch?v=5X_7Xt2ga-s

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Lazlo wrote:

Most bandsaws have tires with varying amounts of crown, and where on the crown your blade is riding has a lot to do with how it behaves. If you are lucky enough to have the wheels directly in line with one another (vertically), they are not tilted in any way (forwards or backwards, left or right), and the blade is riding directly in the center of the crown on both wheels, then you might stand a chance of the blade having little to no "lead" (the tendency for a blade to cut out of parallel with the wheel axles) or twist (where the blade is riding in front of the crown on one wheel and behind it on the other). Rarely do both blade and machine coexist in perfect harmony, so it's difficult to achieve such perfection; but you should at least attempt to ensure that the wheels on your saw are properly adjusted (a good book as mentioned by others can be helpful here). Blade lead isn't usually a big problem, but twist can be a pain, particularly if you're trying to resaw something.

The "twist" I think you're referring to here is simply the back of the blade rubbing the sidewalls of the kerf as you try to cut a tight curve. This could be a simple matter of using a blade too large to make the curve, or one with very little "set", causing a kerf too narrow to allow much navigation. By all means, your upper and lower guide bearings should be adjusted to "contain" the blade should such twist occur, but do not rely on them to prevent the twist; think of those bearings as simply a guard against allowing the twist to propagate up (or down) to the drive wheels, causing the blade to mis-track, jump off, or even break. You should instead select a good sharp blade of the correct size and sufficient set to navigate the tightest radius you intend to cut. Your blade should never wander or bind if this is the case.
You also mention that you use the bandsaw very rarely, so there is another trick to preventing binds and twists of which you might not be aware. Keep the workpiece moving as you navigate a tight curve. Cutting curves takes a bit of practice, and the natural tendency seems to be to cut in short bursts, stopping the advancement of the workpiece into the blade as you reposition it according to the curve. Don't do this. Keep the workpiece moving into the blade (however slowly) as you arc it into the curve; this will work wonders towards preventing binds and twists.
Hope this helps.
--
See Nad. See Nad go. Go Nad!
To reply, eat the taco.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Steve Turner wrote:

Or it could be that he isn't keeping his stock flat on the table. Not all that likely but possible.
--

dadiOH
____________________________
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
There are upper and lower guides.
What size blade?
How thick is the stock you are working with?
As mentioned the Mark Duginske book or dvd. Search on youtube for bandsaw videos.
(Amazon.com product link shortened)31007693&sr=8-1

http://www.youtube.com/results?search_query
ndsaw&search_type=&aq=f

http://www.youtube.com/watch?v=Xg9JaAckK9o


http://www.youtube.com/watch?v
j15Is-Wjs
wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I'm going to step in here and agree with what most every one has mentioned. However, IMHO most of what causes a blade to not be stable is actually the saw. I had a Craftsman BS for several years, it was so much trouble to keep in tune that I avoided using it and it basically became a waste of space. Three years ago I purchased an 18" Rikon BS, it was improvement over the Craftsman but IMHO not much of an improvement. I originally bought the Rikon sight unseen from Woodcraft and returned it 2 weeks later for a refund. Four months later I received my Laguna 16" HD BS. To change from a 1/2" blade to a 1-1/4" blade takes me approximately 10 minutes. I adjust the upper and lower guides strictly by feel and sight and that is absolutely all that I have to do to get perfect tracking with either size or brand blade. No more plucking the blade for the musical note, I strictly go by the built in gauge. I too once thought that cutting on a band saw was some what of an acquired skill. Buying the Laguna instantly gave me all the skill that I needed. I can adjust the fence for drift but there is no drift. I can tilt the top wheel but very seldom have to and if needed when going from a narrow blade to a wider blade the adjustment knob might get a 1/4 turn for a very subtle adjustment. The saw and what ever blade is such a dream to work with that I look for excuses to use it.
If you have an older Delta BS you should have a pretty descent machine but it is probably not a big honk'n heavy duty machine. You may be expecting too much from it. I suspect that you are going to be limited to a 1/2" blade for resawing, bigger than that and you will probably not be able to tension the blade enough for satisfactory results assuming a wider blade will even fit. Additionally, wider blades typically do not do well when made to go around smaller radius wheels. Good guides are also essential. I had roller bearings and absolutely hated them and cannot recommend them for various reasons. I do recommend ceramic guides and again IMHO the more points of contact the better. My Laguna has 10 points where the ceramic touches the blade.
I am in no way trying to sell you a Laguna BS but only pointing out that when I finally stepped up to this caliber of saw, blade size, blade brand, and my skills were no longer a factor in obtaining great results. I was cutting see-through thin 4" wide Oak veneer with the throw-in 1/2" "non-resaw" blade that came with the saw the first week. This fall I able to cut, with a 1-1/4" premium resaw blade, 1x6 hard maple in to 5, 5/32" thick veneers per board very quickly and with only a pass or two through the drum sander to clean up the slight tooth marks.
Use the suggestions made by others but know that if you still are not happy there are better saws out there. Yes you will have to spend lots more money but you do get a machine that makes cutting and resawing almost effortless and almost instantly after you uncrate it. Laguna also sells their 10 point ceramic guides for other make saws.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Interesting comments. A 1-1/4" blade is a honking wide blade. The width of that blade compared to a 1/2" blade has to offer a substantial improvement when comparing wander and twist and resawing. You sound pretty happy with your Laguna.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote in message

The 1-1/4" blade is very stable when resawing. With the 4.5hp Baldor motor it rips and or resaws faster than my cabinet saw. This particular blade however is made for resawing, it is a Laguna Resaw King and pretty expensive and I try to only use it for resawing. As for as an improvement over the 1/2" blade concerning wander and twist I really see don't see much of a difference. While the 1/2" blade has virtually no wander or twist the comparison in that respect does not reflect much of a difference. The saw literally has the back bone, HD components, tensioning spring , "and" guides that afford very good and consistent blade mounting. Having said that and I have never tried this but the reps at MiniMax indicated that their MM16 BS really did not need guides for the blade to track properly with out twist or wander. I was considering the MM16 and the Laguna LT16HD. Ultimately I preferred the Laguna guides over the MiniMax guides. The Laguna guides literally capture the blade on both sides in an upper and lower spot above the table and again below the table. The guides make certain that the blade is exiting and entering the upper and lower guides perpendicular to the bottom of the top guide and the top of the bottom guide. Laguna has a very good video on the Laguna guides at their web site. And yes I am very happy with my Laguna BS. The improvement comparison was similar to when I upgraded from my 1 hp Craftsman contractors saw to my 3hp Jet Cabinet saw, actually the improvement was probably much better than that.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.