Replies

1. 
   gerry001 | May 22, 2002 07:49pm | #1

   Campbelldust,

   The ridges will always be there; it's the nature of the beast. The more teeth-per-inch (tpi) for the blade, the smoother the cut, but the less the amount of sawdust they can carry away. IOW, I can resaw thin slices from 2" hardwood with a 3/16-10tpi blade and get a pretty smooth finish (still some ridges, though). To make it though a 10" wide piece, I'd have to go to a 3tpi blade, and the surface will be rougher.

   As to roughness, and beyond general saw alignment, check a few more things. Rotate the upper wheel (with BS off, please) and watch the back of your blade. If it's moving forward-and-back, that adds to the roughness. Thrust bearing distance will have an impact. Your guide blocks will have little impact, since you're moving in a straight line.

   Feed rate shouldn't be too fast or you can't clear the sawdust fast enough. Tension should be high enough so that, at your feed rate, the blade is held rigid (no crowning, i.e. bowing). Timberwolf's tension guidelines work but you need to keep the feed rate down due to the low tension the recommend. This, of course, gives you longer blade life (they say). You can up the tension a bit and increase the feed rate if you like, since their blade design does a nice job of clearing the kerf.

   In general, a slow and very-very steady feed rate will give you a visibly improved cut. Try a test case where you start slow and change the feed rate several times, at points you've marked with a pencil. When done, examine closely and decide what you like. When cutting veneer I set up for one slow, continuous feed, never stopping or slowing down just to shift hands or scratch itch, since you'll see that in the cut edge.

   Push sticks--I use two types. One is a modified TS push stick, where the end piece swivels on a pivit. It allows me to give equal pressure across a several-inch area and holds it even if the hand angle changes. For most cases, I just use a notched piece of wood, so I don't feel guilty when it hits the blade. With resawing, as you're near the end, you may need to steady and pull from the other side, since your entry side now is too small to hold flat and firm. This, of course, depends upon your resaw fence type, e.g. high-regular, point, 2-point, half-fence, etc. I use a full length fence, with a face board to the right height.

   For large pieces, I also use a magnetic feather board to hold the bottom against the fence.

   If you've read the other posts here, the one thing you shouldn't do is use spray Pam to prevent straining your tension (no, don't ask me to explain that:-).

   Gerry

1. 
   ccampbell | May 22, 2002 08:01pm | #2

   Thanks for the feedback, Gerry.  My blade is a 3tpi 3/4", recommended by Suffolk for resawing.  It does move back and forth some, and rubs the guides on either side.  Is there an adjustment for this?

   So far I've just been using the tension guide on the saw since I dont' really know what I'm doing yet.

   Last night I was experiencing what you describe about pausing and seeing it in the cut.  That is partly why I decided to ask for technique advice.  I couldn't find a way to get a smooth feed from start to finish.  I would be pushing along, then get a few inches from the blade and need to switch to a push stick or move one hand to the back to pull and the hand change would show up in the cut.  I don't have any idea if I'm doing it right.

   Also last night I was using the stock fence with the metal rod attached for resawing.  It seemed to me like the rod made it a little more squirrelly.  Is it better/okay to just use the fence by itself?

1. 
   gerry001 | May 22, 2002 08:30pm | #3

   I use the same blade for thick stock. I've seen that blade vary from 0.008 to 0.032, and they should be near the former. There's no way to adjust this. Here I assume, of course, that your BS is okay.

   For tension read up on the stuff in Suffolk's web site on their blades.

   Maintaining a smooth feed is sorta a little dance and takes practice.

   Now, what's this about rubbing the guides on either side? Do you mean the guide blocks, and do you know how to set them? Hopefully, you don't mean the metal block retainers...

   On the "metal rod", I don't know what that is. I have the Jet, and just use the fence with a face board high enough for the stock width. I add paper shims to get it perfectly square with the table. You might want to pick up a book on the BS, I recommend Lonnie Bird.

   Gerry

1. 
   ccampbell | May 22, 2002 09:27pm | #4

   What I meant about rubbing the blocks on either side was that the blade doesn't seem to hold dead still when the saw is running.  It has a little play in the path it takes, so that it may rub one or the other of the guide blocks as it moves.  I have adjusted the guide blocks as close as I find reasonable, given that.  How close should they be?

   The resaw rod I'm talking about comes with the stock Delta (and Jet, I think) fence.  It's basically a short metal rod that attaches upright to the face of the fence and is held in position by a hand screw from the other side of the fence.  It is supposed to give you a swivel point to more easily follow the line and correct for blade wander.  It seems to me like it also allows you to be able to get off of the line just as easily.  I'm wondering if I shouldn't just use the fence alone.

1. 
   gerry001 | May 23, 2002 02:11am | #5

   If you turn the upper wheel by hand, how much side-to-side play is there? That should be pretty darn steady in that direction. What I referred to earlier was a forward-back movement, not this side-to-side. Unplug the saw and check while turning by hand is the best. Use standard tension on the blade. With a good blade and everything well aligned, it shouldn't move in either direction. If the blade wasn't perfectly welded, it will move slightly back-and-forth.

   For any type of blade movement, look first for the periodicity, and see if it relates to the wheels, blade, or pulley. Take your time, and look very carefully at what's happening.

   While a soft spot in the tire can cause what you describe, some other things will only show up when the machine is powered. For instance, the upper wheel can move vertically, but is restrained by the tension spring. Too little tension will allow it to bounce, although this is unlikely since the blade probably wouldn't stay on at that point. If the pulley belt was sharply bent in shipping it may not run smooth until it wears straight again, and that could cause a bounce in the wheel, even under normal tension. Look and listen carefully. See how it reacts to a change in tension.

   The Delta has a difference fence than the Jet, and I don't recall that metal rod. You'd need a Delta owner to respond on that one.

   As for following blade wander, the Suffolk blades generally have no bias, so there's no need to correct for lead. My fence is just set inline with the blade, and is never changed. I have a variety of blade sizes, all from Suffolk.

   Gerry

2. 
   Ricky_Yu | May 24, 2002 11:19am | #6

   Since I am a Delta owner, I'll weigh in about the metal rod or guide post for the rip fence. You are correct about its usage. Personally, I use it for reswaing, but I could see how it could be vexing in that while I try to follow my cut line, I constantly have to make sure that my stock is tight along the entire length of the guide post as I run it through.

   If you want to go fence only, then you have to account for the drift angle of the blade. I recommend Mark Duginske's band saw book to explain this procedure (and many others) more thoroughly, but in a nutshell get some straight stock about two feet long and rip off a piece about 3 or 4 inches wide. Draw a line lengthwise right down the middle. On the bandsaw, cut along the line freehand. Try to follow the line as closely and smoothly as possible. About halfway through the piece, you will see the stock angled a certain way in order to cut along the line. This is the drift angle. At this point, turn off the saw, but leave the stock in place. Realign your rip fence to match this angle. The Delta fence has a decent range for readjustment, but if the drift angle is beyond this range, then a shopmade rip fence (straight board and a couple of c-clamps) will have to suffice.

3. 
   DonStephan | May 25, 2002 03:10am | #7

   Heartily second the recommendation to get the second Duginske book, Band Saw Bench Guide or some such title. I learned quite a lot regarding band saw tune up. He also addresses ridges in the sawn surface.