Line reading problems

flip · April 02, 2007, 04:06:03 PM

I must be losing my mind. I'm cutting some red oak for a guy this weekend and for some reason am unable to cut 1" boards using my scale. I find that sometimes it is easier to use the magnetic scales than the setworks. So, he wants 1" boards and I pull out the scale with 1" and start going to town. Get my slabs off and get ready to go. I move down to 1" and take a test cut, measure and adjust my scale for my next board. Board comes off perfect 1", I go up, come back and split the line for my next board. The scale is set up to accomodate for the 1/16 kerf so I ASSume all is well. Set up for next cut and go in about 1/2" but something looks wrong so I back out and notice it is only a thin 7/8" ???. I figure I'm losing my mind so I take another test cut and it is a perfect 1" and I reset my scale. I know this : the blades are new so set is not the culprit. My tape measure is accurate. I don't need glasses to see. I was not drinking. Then log was not moving. I got the scales at Timber King this past fall.

I don't really like the scale strips I am using and may have some of my own made. Any ideas what my problem is?? I know I'm asking a loaded question but...

Tom · April 02, 2007, 04:27:37 PM

Sounds like your scale is a true scale rather than a quarter scale that includes kerf.

Put your tape measure on the scale.

ronwood · April 02, 2007, 04:50:14 PM

flip,

I have notice on my scale that I need to look the same way each time. What I mean by that is I need to maintain the same eye level each time. On the woodmizer scale the indicator is some distance back from the scale. Not sure if that may be some of your problem.

Ron

Ron Wenrich · April 02, 2007, 05:30:24 PM

Since you got the scale last fall, is this the first you've had any problems with it or has it been a problem since last fall?

flip · April 02, 2007, 05:39:41 PM

Let me explain the scale since I'm using 1" as my marker and it has a 1/16" kerf figured in already. The 1" goes from black to white blocks for about 24". The way I was told to use it was to put my mark between the white and black and you should have a 1" board, kerf already figured in. How it has been working ever since I've had it was that I had to go into the next "block" about 1/16"-1/8" to get my 1" board. Let me get a pic. tonight so you can have a good idea of what I'm talking about. Being a 32nd over or under is not a great concern, but more than that is unacceptable for me.

It really shouldn't be THIS hard.

LeeB · April 02, 2007, 07:29:46 PM

I have the same sale on my TK 1200. I never did like it either for the same reasons. I always just used the true scale and did the math for the kerf. For actual 1", I would drop 1 1/8 for each cut. Mostly I would just drop 1 1/4 per drop and get 1 3/32 thick boards. LeeB

Ron Wenrich · April 02, 2007, 08:21:41 PM

Before I started using my Silvatech setworks, I always used the math method. That always got me to a good starting point. Every circle mill I have run has had some sort of mechanical stops for the setworks.

But, my setworks moves the log, not the head. With mechanical stops you get a real consistent cut every time.

ladylake · April 02, 2007, 08:30:38 PM

why don't you use the setworks? Lots of stress in the logs?

flip · April 03, 2007, 08:29:47 AM

Here's the scale...

I put my mark between the white and black blocks which in theory, should divide the kerf between the top and bottom cuts. The mark is 1/64 whick may be amplifying any misreading on my part, but like I said I can live with being off 1/32 but any more is just not acceptable. My mark usually ends up being a 1/16" to 1/8" below the block I'm using. Yes, I am resetting my scale when I have my test cut at 1". I think I'll move my mark closer to the scale tonight and see if that helps. I think I'm an idiot...maybe I should be drinking while I cut :

dad2nine · April 03, 2007, 09:43:15 AM

Lots of strange thing can happen. When my WM starts cutting funky I run through a few check list items. So far it's been one or a combination of these that has fixed my problem and usually has something to do with the blade. You can also listen and get a good idea what the problem is too. Mine sings a song, when it's singing differently it's time to stop and figure out why.

* Are the bed rails clean?
* is the blade sharp and in good condition?
* is the blade tensioned? I tighten mind down way more than WM recommended, lets put it this way the WM gauge don't read that high.
* is there enough joy dish washing soap in my water lube mix?
* is my head travel speed to high / low?
* remove blade check blade guide assemblies are they good and tight?
* replace the blade with a freshly sharpened set blade.
* is the mill level?
* Is the the mill head chain good and clean, lubed, is it too tight?
* Is the belt on the motor that advances the head tight, is it slipping?
* is the log weird? - replace log and try another.

Hope this helps.

raycon · April 03, 2007, 10:01:23 AM

What thickness bands you using? I set my kerf allowance to 2 times the band thickness. Right now its set for 3/32. This led to me making my own scales on one of the mills. Pretty easy process. I'd rather come in a 32nd to 16th over anyway so thats the side I error to.

flip · April 03, 2007, 10:07:17 AM

Standard Munks .042 blades (new) 7/8 tooth spacing.

Tom · April 03, 2007, 10:55:11 AM

Personally, I think that your expectations of 1/32 accuracy is unacceptable. It would be nice to be able to hold that, be it isn't realistic. Even if your saw can do it, the wood can't, and won't. Drying will often cause shrinkage greater than that dependent on the orientation of the grain.

I think that you need better instructions than "putting the mark between the white and black" to use that scale. It confuses me to look at it. If you do, it better be the same place in relativity each time.

What I am noting is that the 1" black marks seem to be 1 1/16" long and the white between them is about the same. Paralax will eat up 1/16 of an inch and you won't even know it. The set in the blade is probably .021, or better, on each side. Just the set in the blade could eat up 1/16".

As I look at the black mark in the middle of the picture, I'm not so sure your scale is giving you even a 1/16" for kerf.

I'm having problems following your procedure, too. What is this "test" cut you are performing? You say you are dropping the head to an inch to adjust the scale. Do you mean that you are taking the blade to an inch above the bed, or are you dropping it an inch below the top of the cant? When you are making these adjustments, what is the relativity of the place between the black and white where you will put your mark and the readings on the true scale next to it? Those can't change and will indicate a positioning error.

Cut a cant using your true scale and make your drops 1/16"

Remember that you are using a sawmill, not a shop tool. There are a lot joints, fixtures, and moveable parts between the teeth on the band and that little line on the scale.

Larry · April 03, 2007, 11:20:06 AM

You need a sharp pointer as close to the scale as possible to reduce parallax. Keep the point adjusted where you can still see the black and white. TK has had a few different styles of scale's over the years...and I had one that was inaccurate due to stretch.

Better yet is the home made scale using a black wire. When set it is easy to see white space on each side of the wire. It is simple and no way to make a miscut due to confusion on the scale.

I'll normally run better than plus or minus 1/32" and I'm not toggling my up down button to get it either.

Pictures on this thread is a better explaination of a TK scale along with my home made scale.

https://forestryforum.com/board/index.php?topic=6398.0

flip · April 03, 2007, 12:15:47 PM

If you measure the spaces they measure 1 1/16" which includes the kerf. My test cut is basically when it's time to cut a few boards off a face I will advance my head until the blade touches the cant, maybe going in 1/4", back the head off and get the tape measure out and make sure the board is 1" or just a 1/32" over. I set my scale to the pointer where the pointer basically bisects the the line where the black and white boxes meet. I make my cut, pull board off, bump up 1/8" come back, drop down until my pointer bisects the next black and white blocks and make sure, by making another test cut I'm at 1". Usually it thin by a heavy1/16" so I end up dropping down to compensate.

Brian_Rhoad · April 03, 2007, 12:51:46 PM

Woodmizer scales are a line at each set point. They are very easy to read. I got some stick-on scales for my Breezewood mill from Marty and they work great! They have scales for hardwoods and softwoods.

raycon · April 03, 2007, 01:34:40 PM

Whats the set in the bands? Reads like you should add an extra 32nd allowance for the kerf.

Tom if you ever decide to make a video series on milling I'm first in line to purchase one.

fstedy · April 03, 2007, 01:47:09 PM

I use the standard TK scale and move down 1 1/8 for each cut gives me good consistant 1"+ boards on the TK B20 same as your are using. For 4/4 use 1 1/4" move down each time. I don't trust the TK setworks they aren't consistant never had worked properly. I thought you had that problem solved with the extra cable reel for the setworks ground? Its easy to use the scale once you get used to it. Remember its rough cut lumber meant to be finished further. The 1/8" alowence for dimension boards and 1/4" for 4/4 5/4 ect. works well for me on the B-20. Don't know about sets on WM these were meant for your TK B-20 which we are both using. Send me an IM if you want the proceedure I use.

flip · April 03, 2007, 02:06:55 PM

How I understand it is that if you split the line you leave a 1/32" on top and bottom-splitting the 1/16" from the last board. Too complicated...but yet so easy. I guess why I'm bothered by this is that the customer wants 1" boards, I suggested 1 1/8" he makes cabinetry and says most of the stuff he uses is 3/4 or 5/8. Maybe I'm just being paranoid about his satisfaction with my work and frustrated because I can't trust what my scale reads. If it were just siding or something like that I wouldn't get so bothered but it's all grade stuff I'm cutting now.

BBTom · April 03, 2007, 02:21:27 PM

Kerf on .042 blades is somewhere around .092 - .096, halfway between 1/8" (.125) and 1/16"(.0625). If you drop exactly 1 1/16 (1.0625)" you will normally be making a ~31/32 (.9685)" board.

I am not trying to be anal, but the point is that 1/16" is not enough for the kerf. I think WM allows 1/8" for kerf on its scales.

flip · April 03, 2007, 02:27:51 PM

That would make perfect sense WHY each subsequent cut seems to be "growing" on the scale. I would rather take a 1/8" kerf into account and be fat than follow my scale and keep getting thinner. I do not find any of that to be anal retentive at all.

Furby · April 03, 2007, 03:08:16 PM

Next time you do a test cut.... measure your kerf in the cant. ;)

Dan_Shade · April 03, 2007, 03:18:21 PM

.045+.023+.023 = .091 = ~3/32

flip · April 03, 2007, 03:21:35 PM

All well and good but it does not help much when your scale is *supposed* to have taken that into account. Makes the scale pretty much worthless after the 2nd or 3rd cuts.