I picked up an old JWBS-14 not long ago – I’ve used bandsaws before, but not owned one.
I got a new fence, put in a new belt (which eliminated the wobbling), got new bearing guides, and new timberwolf blades.
Seems to work pretty well. However, I was resawing some 5″ walnut with a 1/2″ 3tpi blade, and it started screaming. It was still cutting pretty good and not burning at all, but the noise was ungodly. The screaming stopped when I backed off the cut.
What’s the fix, do you think? I think I have it adjusted correctly… but I’m a rookie, what do I know??
Thanks for the help!
Chris
Replies
Sounds like your blade is hitting one of the guide bearings.
Assuming your wheels are tracking correctly and your fence is aligned to the blade to account for drift the guide bearings shouldn't be touching the blade during cutting. The thrust bearing does touch the blade but only when there is material being pushed into the blade mine squeals every once in awhile but a simple readjustment usually resolves that problem.
>bearings shouldn't be touching the blade during cutting<When should the bearings touch the blade ; if ever ? What are the bearings for any way ?rocGive me six hours to chop down a tree and I will spend the first four sharpening the axe. Abraham Lincoln ( 54° shaves )
Roc,
"When should the bearings touch the blade ; if ever ? What are the bearings for any way ?"BEARINGS SHOULD NEVER TOUCH THE BLADE. If you try, you can get them almost a quarter inch from the blade. What are the purpose of bearings? They are a test of woodworker's willingness to submit to the rules of the "tool gods" who demand that the bearings be placed within .0000000000000001 of the blade and not touch it even when the weld comes through. Of course, with sufficient care, one can grind the weld down to almost nothing. Lie Nielsen is coming up with a special tool which will do this. It will be their first foray into hand tools for the purpose of fettling machine tools. I am talking to SawStop to see if they can use their technology to develop an attachment for setting band saw bearings within a few thousandths of the blade. I am developing a special hat for use while bandsawing. It can also be used for dovetailing by hand. It has two lights on it, and a fan. THis automatically places the light in the correct position for optimal visibility of knife and pencil marks, and the fan keeps the dust off. Am also considering adding an IV-drip capability to the hat which will allow nervous woodworkers to use modern chemicals to relax and enjoy their hobby. The great thing about Knots is that you can ask a question and get back "THE" answer very quickly. I am glad to have been able to help. Now let's get down to some REAL woodworking questions, and look at the issues inherent in developing a lightweight, flexible, efficient, comfortable bicycle using all wood parts. I believe the answer to construction problems is to use Maloof type joints. Stay sane.
MelPS I am developing a method of testing the validity of answers to questions asked on Knots so that newbies can tell which of alternative answers given to them is the best. I am trying different parameters to see which gives the best results. So far, the computer tells me that the best way to do this is read the name of the person who posted each reply. For a small fee, I can provide ratings for each name. :-)Measure your output in smiles per board foot.
> IV-drip capability <Don't forget us pisces wood workers. For me at least I suggest something caffeinated. Perhaps an espresso con panna drip. I think I will skip the IV and go straight into the old noggin via my flapavocal labial commissure.Oh yessss . . . that would do nicely. Please let me know when you go to production and I will place an order for mine.rocPS: Oh and thanks for straightening me out on the blade bearing thing.Give me six hours to chop down a tree and I will spend the first four sharpening the axe. Abraham Lincoln ( 54° shaves )
Edited 10/27/2009 11:09 pm by roc
Guide bearings are the Kung Fu rice paper of the bandsaw, and are there to teach one the zen of feed rates and such. Just as Master Po taught Kane to walk on the rice paper without tearing it, the never-touched guide bearing, adjusted to within a paper-thickness of the blade, is the goal. Once the goal is achieved, the bandsawyer is allowed to burn the profile of the blade into the inside of his/her forearms. ;-)
>never-touched guide bearing, adjusted to within a paper-thickness of the blade<My vision is a bit, well you know, as it is. Often I am trying to see the blade from six or eight feet back on the end of a plank and now you tell me I gotta see the thouish gap between blade and bearing.Wood working is harder than the layman can imagine ! No prob though I will just listen for the sound of the change in air whoosh between blade and bearing and go by that.I may be loosing my "eagle sight" but at least I still have my "cat box reflexes".: )rocGive me six hours to chop down a tree and I will spend the first four sharpening the axe. Abraham Lincoln ( 54° shaves )
>Master Po . . . Kane walking on the rice paper . . . Once the goal is achieved, the bandsawyer is allowed to burn the profile of the blade into the inside of his/her forearms. ;-)<I see. I was never good with the walking on the rice paper thing. I used to get brownie crumbs from my lap on the paper which left unsightly, spreading, oil stains.I am allergic to pain and stuff to. This is going to be more difficult than I thought. Guess I will just stick with my Laguna. It is forgiving of my unworthiness. As long as the guides are set to just lightly touch the blade.: )rocGive me six hours to chop down a tree and I will spend the first four sharpening the axe. Abraham Lincoln ( 54° shaves )
>bearings shouldn't be touching the blade during cutting<
When should the bearings touch the blade ; if ever ? What are the bearings for any way ?
roc...
I'll give you a little different perspective than Mel. In re-saw I discovered it is rare for my blade to touch the bearings. I set the side bearing at about 1 mm which is farther than recommended on my larger re-saw BS. I set the rear thrust about the same. So.. why do I bother to set the side guides shallow as IMO they really don't come into play?
In my mind I feel more comfortable with side guides set if the blade breaks as I have a vision of them helping contain the blade to some degree. But.. with that said I have never had a blade break in re-saw but I have on a smaller BS in curve cutting and in TS kick-back.. you cannot predict what will happen.
Also.... if I ever see my blade touch the rear thrust bearing the way I have it set loose... I know to slow the feed rate as I am forcing the cut even though that rarely happens as you just get the feel after you have re-sawed a lot. And... if I see the blade starting to touch the side guides often in re-saw... it is a tip-off to me that the blade is beginning to dull or possibly I have lost a tooth set and I evaluate further to make a determination if a blade change is necessary.
But... the bearing play a major role in curve cutting and I set them as reccomended on my smaller BS with a 1/4" blade I use to cut many templates. The blade will definitely touch the bearings often there making radius cuts and they help prevent the blade twisting.. distorting and breaking. The reason you have to flatten carbon guides often and replace wooden ones.
So IMO... the statement about blade not touching guides only applies to re-saw.. not curve cutting which are apples and oranges. And to me they are important on both re-saw and curve cutting but.. for totally different purposes.
Sarge..
Woodworkers' Guild of Georgia
Edited 10/27/2009 11:11 am ET by SARGEgrinder47
Edited 10/27/2009 11:13 am ET by SARGEgrinder47
>you cannot predict what will happen<Sure I can. Well in general any way. What will happen will usually be something other than what I expect will happen. At least when I make plans or go out my front door.The wood shop, being a magical place, thankfully is all together different and fairly predictable.In the book called Mostly Harmless by Douglas Adams Trisha says that trying to live life by any plan that you actually work out is like buying ingredients for a recipe at the super market.You get one of those carts that simply will not go in the direction you push it and end up buying completely different stuff. What do ya do with it ? What do ya do with the recipe? She said she didn't know.I don't know either. Thanks for trying to help though.: )rocGive me six hours to chop down a tree and I will spend the first four sharpening the axe. Abraham Lincoln ( 54° shaves )
Edited 10/28/2009 12:18 am by roc
I've had this happen occasionally with tall cuts, especially in difficult/green woods. The band starts to sing in the cut. It tends to be worse if the band is dull or if the workpiece isn't going straight (moving away from the fence, twisting, etc). You can try messing with the tension, but if you're getting a good cut (ie flat, straight) I don't think there's anything to worry about.
Pete
Edited 10/26/2009 11:03 pm ET by PeteBradley
Ditto Pete B...
Sarge..
Woodworkers' Guild of Georgia
Check the blade tension, too little may cause the blade to wander and scream. Usually 3/8" deflection is about right. If the noise is only on feeding thru the blade this may be a simple answer. My saw needs a spray shot at the motor shaft where it comes thru the pillow block to the bottom wheel. My saw would "scream" only at start up until I realized what the fix was. This sounds different than your problem.
A friend of mine had a similar problem only with a new blade. The manufacturer suggested a lower than normal blade tension. I suppose he just tensioned the blade too low as I retensioned the blade,the noise stopped.
mike
Someone at Timberwolf once told me to set the blade tension, with the saw off, to the built-in recommendation on the bandsaw. Mine has a recommended setting based on the width of the blade. Their advice was then to turn on the bandsaw and carefully loosed the tension until the blade started wobbling, then tighten just enough to stop the wobbling. They said the tension set this way probably would be less than the saw's built-in setting.
When I had screaming as described, it was due to teh bearing behind the balde that was going bad. (The blade only contacted the bearing when wood was being sawn.) Replaced the bearing and the screaming was gone.
Don, those instruction are just a sentence or two short of accurate. Here's that last step, from the Timberwolf web site (I've bolded the missing bit):
Not everyone believes in this form of blade tensioning, but many of us use it with success. The proof is in the cutting, of course.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
So when you adjust it this way, do you have to back off all the guides?
Often I forget to back off the tension after sawing, so I only have to adjust the tension the first day. To find the "flutter" tension I simply raise the upper arm assembly as much as possible, giving the blade some 8" or so to flutter. After adjusting the tension I lower the upper arm so the wood being cut just clears the lower end of it.
Well, that is a relief. I've never done it because I thought I had to relieve all the guides and that is a job to readjust the lower ones on a MM16. Thanks.
>job to readjust the lower ones on a MM16<Does it help to tilt the table ? It helps on my Laguna.rocGive me six hours to chop down a tree and I will spend the first four sharpening the axe. Abraham Lincoln ( 54° shaves )
I had it also. Operatic saw. Thrust bearing was bad/frozen. Nice groove in it from the blade singing. Also,blade should only touch bearing on outside moving ring.Have seen them come centered from factory.
Full tension.Replaced bearing. Saw all happy.
As a "rookie" you may want to buy Lonnie Bird's Band Saw Book. It will tell you how to set up and align your saw, set the side and back guides and answer any questions you have. It will also tell you about blades and when to use each one.
You are getting some dubious advice here.
Your problem may be caused by a bad bearing but sometimes a good bearing will make a fair amount of racket during a resaw cut.
The after market side ball or roller bearings are more trouble than they are worth. For resawing going back to steel, or even better, ceramic side blocks. They will save you time, money, trouble, and noise.
No matter what side bearings you use, ceramic, steel, or roller, they should be set close to the blade, setting them back the thickness of a piece of paper is a good guide. Before powering up the machine, rotate the entire blade through the guides once, while turning the wheels by hand, to make sure that the blade doesn't have a bad weld or a kink that will cause the blade to jam in the guides.
Fixed ceramic thrust bearings also work better than the roller type, and again they are noise free and require virtually no maintenance. No matter what type of bearing you use, both of the thrust bearings should just barely touch the back of the blade when the blade isn't actually cutting stock. The blade will almost always touch the bearings during actual cutting, but the bearings are designed to handle that.
On most 14" saws, where the thrust bearing are positioned crosswise to the blade, the upper and lower thrust bearings are mounted on hex shaped shanks in the blade guide supports. Removing and rotating the hexes into different orientations in their holes will change the side to side position of the thrust bearing. For ball bearings use the bearing position that aligns the blade as close to the outside edge of the bearing as possible. For ceramic bearings the opposite orientation, with the blade running close to the center of the bearing, is best.
Always tension and track the saw blade with the guides and thrust bearings pulled well back before making adjustments to bring the guides and thrust bearings close to the blade. Set the thrust bearings first then the side bearings.
John White
Shop Manager for FWW Magazine, 1998 to 2007
Edited 10/28/2009 6:24 pm ET by JohnWW
hi john,
what about when you release the tension on the blade. in my case (21" felder/acm), i typically re-tension with the guides and bearings out as you suggested, and then re-set the bearings and then guides. i've had other (trusted) woodworkers tell me i could just leave the bearings set, re-tension, and then adjust as needed. what's your opinion?
if it's worth doing at all, then it's worth doing well.
You have got to be kidding! (OK, I know you're not) Seriously though, the object is to run the machine; don't do anything that requires you to fiddle with it every time. Just back it off a few turns when you want to detension, then put it back to the same spot when it's time to use it again.Pete
Edited 11/1/2009 7:41 pm ET by PeteBradley
Adjustments to the blade tension do not require doing anything with the guides and thrust bearings unless you are changing the blade. You can in fact change the blade out without changing the guides and thrust bushing if you are replacing with an identical blade.Don
If you are only releasing the tension and resetting to the exact same tension later you don't need to back off and then readjust the guides. If the tension is different then the blade will track differently and the guides should be readjusted. You shouldn't adjust the thrust bearings with the side guides already up against the blades, if the blade moves back too far the saw teeth will hit the side guides which can damage the blade and the guides.Having already said that I don't know how important it is that a saw's wheels be perfectly coplanar, I also have to say that, so far as I know, no one has ever run a test to see if releasing blade tension makes any difference. I have seen a lot of different theories about why it should be done but no real data. Older text books on band saws never mentioned the subject. We never released the tension on our bigger band saw in the FWW shop and it ran fine.John White
Shop Manager for FWW Magazine, 1998 to 2007
Yeah, I left out "don't detension at all", but that would be my advice.Pete
So why wouldn't you de-tension the blade after each use?From Suffolk Machinery and Viking Blades
ALWAYS DETENSION YOUR BANDSWhen you are done cutting for the day, take the tension off your blade. Band saw blades, when warmed up from cutting, always stretch; and upon cooling shrink by tens of thousandths of an inch each cooling period. Therefore, blades, when left on the saw over tension themselves and leave the memory of the two wheels in the steel of the band, which will cause cracking in the gullet. When you leave the band on your saw under tension, not only do you distort the crown and flatten out the tires (which makes them very hard), but you also place undue stress on your bearings and shafts. Believe it or not; you can, and will damage your wheel geometry sooner or later and considerably shorten bearing life. You are also crushing your tires or V-belts.Again I defer to the wisdom of the blade manufacturers in this matter.Don
As much as like Suffolk Machinery's blades their website information sections are not well written. They post a lot of information that primarily applies to large lumber mill saw blades and then post it as though it applies to all saws. Small saws aren't tensioned very high so there isn't a lot of stress on the wheels in the first place and if the blade expands when running and then cools off when the job is done it will only come back to the same length and tension it was set at to start. In addition the spring in the tensioner will just move a bit and prevent the tension from increasing even if the blade did shorten a bit for some reason. I have used a lot of saws over the years most of them never had the tension released for months at a time and the machines and blades held up just fine.John White
Shop Manager for FWW Magazine, 1998 to 2007
I will add my voice to Johns here. I am a heavy bandsaw user and never detension on either the 14 or 18 inch.
................................................
Men will never be free until the last king is strangled with the entrails of the last priest.~ Denis Diderot
You'll find that for topics like detensioning, optimum drill speeds, and many other issues that get discussed in forums like this, you can find an 'authority' for almost any position. That's why I hesitated to mention it. A buddy of mine in a professional shop laughs at the notion, and some of the real machine experts over at OWWM argue there's no benefit. Also, some advocates of detensioning are ridiculous. Minimax used to claim in their manual that leaving the tension on will flat spot the tire and unbalance the wheel, as if their balance is so fine that a few grams of rubber would upset it in some 'Princess and the pea'-like fashion. I've also seen claims of increased bearing life, but I have yet to see one with any metallurgical or engineering explanation to back it up and I doubt I'm going to.If detensioning works for you, go for it. I generally detension if I'm not going to run my machine (20" old iron) for a while, otherwise I don't bother. So far no discernable difference. Saws with small wheels may see more effect since there's less tire supporting the band for a given tension, but whether that's really significant, who knows? Tires are cheap when they wear outPete
Edited 11/5/2009 8:17 am ET by PeteBradley
If your saw is reasonably well tuned and all it is doing is squealing you might try a light application of vegetable oil on both sides of the blade. I haven't tried it but the some of the blade manufacturers recommend it.
Follow Michael Fortune's 5 Tips for Better Bandsawing
https://www.finewoodworking.com/ToolGuide/ToolGuidePDF.aspx?id=24093
Don't get to hung up on better guides and bearings, just learn to make the adjustments and start enjoying your saw.
I think that all 14" saws will squeal as they cut. And it gets worse when with the riser kit installed - an extra 6" of blade to resonate. It gets worse as the material gets thicker and harder. I think the worst I have experienced is figured Kentucky Coffeetree
There is not enough mass in the blade to dampen the vibration and the blade is not the most efficient at dust removal so a certain amount of dust gets trapped between the blade and the work and gets pulverized even further. You might back off your feed rate a bit and give the blade a chance to clear the dust. The saw will do a good job, sometimes not as fast as you would like, especially when resawing.
Good hearing protection and good dust collection. The bandsaw will generate some extremely fine dust.
Don
People oil bands on outdoor band mills. I wouldn't want vegetable oil gunk on a vertical machine.
You might not, I might not but the guys a Suffolk Machinery seem to think it is a very good idea and they probably know more about bands than the Knots collective.
The condition is "sparingly"http://www.suffolkmachinery.com/six_rules.asp"CHOOSING THE PROPER BAND SAW BLADE LUBRICATIONNEVER USE WATER as a lubricant on band saw blades. Water is NOT a lubricant and is the WRONG thing to use for many reasons.For the woodworker using 1" and 1 1/4" bands, not only is water unacceptable as a lubricant, but it also rusts the bands causing deep pitting, and inappropriate chip swelling. This prematurely destroys the body of the band and its gullets. It also dry rots your tires or V-belts.For proper lubrication mix HIGH ADHESION CHAIN SAW BAR OIL, with 50% kerosene or diesel fuel. Apply the solution with a spray bottle to BOTH sides of the band about once every four minutes, while the machine is running. When this lubrication is applied, the sound of cutting decreases over 50%. DO NOT APPLY AGAIN until the sound of cutting starts increasing. I guarantee you will be amazed! Longer life; No pitch buildup; No rusted or pitted bands! A great delivery system is the 12 volt windshield washer assembly out of an old car!"Pam" spray-on vegetable shortening is a great lubrication for 3/4" WIDTH AND UNDER band saw blades on vertical saws. (EXAMPLE: Delta, Grizzly, Jet, etc.) Unplug the machine. Spray Pam vegetable shortening on a rag and wipe on both sides of the blade while turning the upper wheel by hand. You will hear a 50% sound reduction when cutting.A band saw blade is a tool.
You must lubricate both sides!In both cases, we know for a fact that lubrication of the body of the band increases band life by over 30%. Applied sparingly, you can cut grade lumber with NO staining to your product."Don
Edited 10/31/2009 1:17 am by Don01
Suffolk sells a lot of band mill equipment. I'm pretty sure they're not recommending bar 'n chain mixed with diesel for indoor use. I see Suffolk recommends wiping on cooking spray sparingly with a rag for vertical machines. I agree that shouldn't be a problem. I'll second the recommendation of wax sticks too. They've worked well for me.Pete
Edited 10/31/2009 9:12 am ET by PeteBradley
I agrree, I once used cooking spray on a metal lathe for a lubricant.It worked but the cleanup was a pita. It is sticky and only comes off with water.Then you have to thouroughly dry everything and reoil with a solvent type.I ran out of the lubricant I usually used and was told that Pam would work okay til I got more lubricant.
mike
I too have had this happen when resawing. I blame it on one of the following. I may be trying to get too much out of a machine. By this I mean that the job may be a little too big for the tool. It may be also that I am feeding too fast for the blade that I am using. Sometimes using a coarser blade(one with fewer teeth per inch) will help. It may also be caused by a dull blade. When resawing on a light duty machine, it is best to start with a new blade.
>What's the fix, do you think? I think I have it adjusted correctly... but I'm a rookie, what do I know??
Another rookie here, but I have learned that those $6 sticks of wax sold for scrollsaws and bandsaws work well. (Won't stop your thrust bearing from being noisy, if that's the source.) I trimmed both sides of several hundred feet of air-dried wood recently with a shot of wax before each board. ymmv. JW may correct me or tell me I'm wrong or simply ignore me.
I agree with JW that most advice here is shots in the dark. I intuitively tuned my saw the way he mentions (good to know it was correct). Don't know why others are telling you this and that and being so long-winded about it. <cough cough-Mel-cough...> ;)
Andy
Thanks, everyone, for all the suggestions! I ended up adjusting the bearings (turns out I forgot to move them when I switched from 1/4" to 1/2" blade... D'oh!) and lubing up the blade. It's still a tad noisy, but certainly tolerable.
Thanks, again, for sharing your knowledge!
Chris
That will make a difference Chris. Now you have to take the "misery" out of your ID.Don
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