Board thickness

Angleblade11 · April 05, 2015, 03:34:03 PM

Ok guys so I'm having issues with boards not being the same all the time. I have a Woodmizer LT 30 manual. The mill was my dads and I always was around it and we used the mill for our own personal use. Sometimes we would saw logs for a friend but for the most part it was just another toy. The guy we bought it off made pencil marks on the ruler for 1-1/4 thickness. Which works fine. But we saw 3/4 most of the time and my dad made a gauge of some sort to mark the log every time before each cut, which is a pain and time consuming. So I made my own marks on the ruler for 3/4 and just can't seem to get it right. I measured from the bed rail up to the blade at it's lowest point and went from there. What I didn't take into consideration was blade thickness and pencil mark thickness. So when I marked up the ruler 3/4 all the boards came out 5/8 or less. So I made 1" marks and boards are coming out 7/8. So do I need to do it again and make 7/8 marks for it to come out 3/4? And each board isn't consistent. They are off about a 1/16 give or take. Am I being to picky with ruff cut lumber or should it be right on the money every time? I want to start sawing for money but would think customers want what they ask for. Although I have bought from a local mill and board thickness was never the same. Is there a better way then pencil marks on the ruler for board thickness? Is there an upgrade I can do of some sort? I know that's a lot to read but thanks for the help.

uler3161 · April 05, 2015, 03:45:40 PM

They should all be fairly consistent on thickness. Also, be consistent on what direction the head is moving when you arrive at your mark. We always start above the mark and come down to our mark. Depending on how much backlash is in your gearbox there could be a lot of difference if you raise the head to the mark on some cuts and come down to the mark on others.

As for having it set to 3/4 and getting 5/8, You're not accounting for saw kerf. Do you have a factory gauge? I'd recommend having one. We used to cut on the 1" on the factory gauge and get about 7/8" boards. But we went to 4/4 (not the same as 1") to get a little more for planing purposes.

homesteader1972 · April 05, 2015, 03:58:36 PM

Just make a new scale like you want. I wanted one for making 2x's that were dimensional sized. I basically just cut a template the size I wanted plus kerf. I got a piece of aluminum at TSC for $9, enough to make two if I needed it. Then scribed vertical lines with a box cutter. Then using the template, scribed the measurements with the cutter too, carefully. Then used a stamp set I had to label them. On the back of this one are the ones for 2x8 an 2x10's. Once I decided how to do it, it didnt take an hour to complete. I rubbed some used motor oil on it to fill in the scribed areas so I can see it. Be sure to start all your measurements on the same line, a couple inches from the bottom so it isnt hidden behind the bracket. Maybe this will help.

drobertson · April 05, 2015, 05:12:52 PM

I like homesteaders idea, with the only exception of how to get the numbers on the scale, taken from the tool room we used to use gauge blocks to verify heights of a given part, so I was thinking if you could accurately cut a board to length in the increments you need, then lower the band to each height and then transfer the mark to the blank scale as homesteader showed. I would lower the band down to it till it just brushes the tooth, making sure the gauge is square to the blade and bed. It will take a little time but once done it would seem to be done. Keep in mind however, that band thickness and kerf would have to be used for this too keep the numbers you marked. I will say, I've never ran a manual, and never have used my scale either, so this may not work at all, the other issue is getting your mill to cut down to the 3/4" mark, this could be problematic, not sure, 7/8" is as low as I go with mine. hope you find a resolution soon,,

Angleblade11 · April 05, 2015, 05:26:08 PM

Never even thought about the backlash in gear box. There is quit some play in it. I'll have to remember to do that. And that is a pretty nice gauge. How much do I allow for saw kerf

Angleblade11 · April 05, 2015, 05:36:56 PM

Drobertson, the lowest my blade goes down is 2-1/4 from the bed rail. We have to put boards underneath the last 2 cuts to finish. Which doesn't help either.

Dave Shepard · April 05, 2015, 05:47:27 PM

When I ran the manual LT40's, I would drop just below my mark, and then raise up to it. This would take out any backlash there might be in the system. You would get so you could land exactly on the mark the first time. What thickness and set bands are you running? I'm running .055" bands with .030" set. That's .115" kerf. Add the kerf to the thickness of board you want to get your spacing on the scale.

thecfarm · April 05, 2015, 06:44:58 PM

I have a hand crank on my mill. And I do what Dave does,I drop down below the mark just a little and crank up to the mark. But I don't have the backlash problem of a gearbox.

reswire · April 05, 2015, 09:02:25 PM

You can also purchase a linear measuring tool with digital readout for under $100.00 online or on e-bay. They will glue or attach easily onto your mill and work extremely well. I had one on my TK 1600, and it was extremely useful. Check them out, they are cheap and easy to install.

gfadvm · April 05, 2015, 09:34:57 PM

I have a magnetic strip on my LT15 that it came with when I bought it used. It is marked for 4/4, 5/4, 6/4, and 8/4. Super simple to use and all my boards are right on thickness wise. There is no manufacturer or info on my tape but I know someone here knows where to get one!

trapper · April 05, 2015, 10:19:51 PM

check out this thread My New "Setworks"
in Sawmills and Milling Sorry dont know how to post a link to it.

Magicman · April 05, 2015, 10:45:32 PM

LINK to My New "Setworks"

Brucer · April 05, 2015, 11:56:02 PM

When you are making a fine adjustment (of any kind) always make the adjustment against the load.

In other words, when you're adjusting the height of your saw head, gravity is pushing the head down so you should be raising the head to the final mark. Make it a habit to lower the head below your mark and then raise it. If you overshoot a little, drop back down and come up to the mark.

The same principle applies to any type of adjustment: tension on your belts, squaring the back stops, tuning your guitar, ...

uler3161 · April 06, 2015, 12:04:29 PM

Quote from: Brucer on April 05, 2015, 11:56:02 PM
When you are making a fine adjustment (of any kind) always make the adjustment against the load.

In other words, when you're adjusting the height of your saw head, gravity is pushing the head down so you should be raising the head to the final mark. Make it a habit to lower the head below your mark and then raise it. If you overshoot a little, drop back down and come up to the mark.

I guess I'm going against the grain here, but I'm confused why everyone says you should raise to your mark? On my mill (and the LT40 manual we had before it), the up/down had an exposed pulley and fine adjustment was much easier coming down to the mark. Just run the head down close to the mark, then roll your hand over the pulley and it would easily "glide" down to the mark. Going the other way isn't nearly as easy because you don't have gravity on your side.

coalsmok · April 06, 2015, 01:18:23 PM

There is a phone app called sawmill calculator. It will give you you cut list after you enter in blade kerf. Just watch though I think some of the other forum members found a few mistakes with it. I have never used it for that, but use the BF calculator side of it to keep up with what I have on hand at the end of a day.

beenthere · April 06, 2015, 03:29:56 PM

uler3161

The "gravity" is the reason you want to "fall" below the mark and come back up to it.
That takes out the slack for better accuracy. Something that becomes second nature when adjusting cutting tools.

uler3161 · April 06, 2015, 04:14:16 PM

Quote from: beenthere on April 06, 2015, 03:29:56 PM
uler3161

The "gravity" is the reason you want to "fall" below the mark and come back up to it.
That takes out the slack for better accuracy. Something that becomes second nature when adjusting cutting tools.

I guess I just find it strange is all. We've been coming down on our cuts for 25 years (and probably around a million bdft) with no problems. I must have OCD because I've been thinking about the physics of it all morning. Maybe we've just had so little backlash that it wasn't really noticeable.

Just curious for those who have an accuset... Does it come down below the cut, then raise up?

homesteader1972 · April 06, 2015, 04:27:01 PM

I was wondering the same thing for the mills with setworks. Like ulcer3161, I come down and use the pulley to stop exactly where I want it. I am not saying I am right at all, but thats how I have been doing it. Do the mills with set works go down then up?

Dave Shepard · April 06, 2015, 05:29:50 PM

My Accuset2 drops below the mark then bumps up.

Peter Drouin · April 06, 2015, 05:59:18 PM

Quote from: Dave Shepard on April 06, 2015, 05:29:50 PM
My Accuset2 drops below the mark then bumps up.

x2

drobertson · April 06, 2015, 06:05:50 PM

the settings on the amount below the set height and the amount up are adjustable, but they do go back up on accusets,

Andre · April 06, 2015, 09:06:52 PM

If things are loose and lubed well enough that gravity can always pull the head to the bottom of the backlash it can work fine to come to a mark while moving down. But if there is enough friction in the system such that vibration causes the head to creep down after you start the cut then it is better to drop below and move back up to the mark.

Magicman · April 06, 2015, 09:52:03 PM

My older Setworks comes down to the mark and so do I.

bandmiller2 · April 07, 2015, 07:17:29 AM

My homebuilt mill has an aluminum yardstick and pointer. When I cut boards they are 1" less kerf, same with dimention, never had anyone complain. If someone requests exactly 2" or a special thickness I drop down the thickness plus 1/8" and remember it for my next cut. If you forget you can always measure the cant. Its simple but simple works. Frank C.

Kbeitz · April 23, 2015, 03:20:01 AM

Quote from: bandmiller2 on April 07, 2015, 07:17:29 AM
My homebuilt mill has an aluminum yardstick and pointer. When I cut boards they are 1" less kerf, same with dimention, never had anyone complain. If someone requests exactly 2" or a special thickness I drop down the thickness plus 1/8" and remember it for my next cut. If you forget you can always measure the cant. Its simple but simple works. Frank C.

I building my mill now... I thought about what your doing and when I put on my aluminum yardstick I'm
going to make my pointer adajustable. this way I can allway have the pointer start ant the inch line.