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General Forestry => Sawmills and Milling => Topic started by: Cruiser_79 on July 20, 2020, 07:46:55 AM

Title: Cheat sheet
Post by: Cruiser_79 on July 20, 2020, 07:46:55 AM
I started making a cheat sheet to make things easier a bit. Getting sick of ending with a useless thin bottom board every time. 
I have a circular scale on my sawmill, with one fixed pointer that shows the distance between saw bed and bottom of my blade. I use that one to make sure my bottom board has a proper dimension. The other pointer has a hand knob and can be adjusted by your self, convenient when you want to cut some other dimensions. You set it when leaving the cut at the size you want, and when you start your new cut you lower it to zero. The cheat sheet would be for the first cut, to make sure I end up with a size I want to. 
But when making a sheet I saw somewhere on the internet this formula; 

heigth = (base dimension x number boards) + number boards -1 x kerf

If i do this, I will miss the kerf on the bottom board or am I that bad in maths? ?   :) 
I would think that the minus 1 shouldn't be in the formula?

I made a simple sketch with what I mean. 


(https://forestryforum.com/gallery/albums/userpics/53550/kerf_losses.jpg?easyrotate_cache=1595245183)



(https://forestryforum.com/gallery/albums/userpics/53550/kerf_losses2.jpg?easyrotate_cache=1595245152)


Title: Re: Cheat sheet
Post by: Sixacresand on July 20, 2020, 08:14:33 AM
I made this chart for my manual mill based on 1/8" blade kerf. 

(https://forestryforum.com/gallery/albums/userpics/25201/Chart_Sawmill.jpg?easyrotate_cache=1365122522)
  
Title: Re: Cheat sheet
Post by: WV Sawmiller on July 20, 2020, 10:20:53 AM
   Attached below is my current cheat sheet. I keep it in a gallon ziplock bag attached to the inside cover of my control panel lid with a heavy magnet about 1" X 2"X 3/8" I got from HF.

  I use a 1/8" kerf for my calculations and set up to leave a 1" board for cuts under 3/4". I set the pointer on my scale to show the thickness of the cant/board below so when my marker says 2" there is a dog board exactly 2" thick left on the bed of my mill. I start using this scale on the 4th face and end up with a board exactly the preset thickness desired. When cutting 8/4 if I start and see I can't get a clean 8/4 but can get a 4/4 I set the mark on the first clean 8/4 then raise the head 1-1/8", cut the scrap slab, drop 1-1/8" to get the 4/4 flitch then change the setting on my SimpleSet back to 8/4 (2-18") and cut to the rails.
Title: Re: Cheat sheet
Post by: Nebraska on July 20, 2020, 12:05:20 PM
Going to print them both off and wall paper the mill shed wall.  It will save some mental gymnastics later. 
Title: Re: Cheat sheet
Post by: Cruiser_79 on July 20, 2020, 01:41:18 PM
Quote from: WV Sawmiller on July 20, 2020, 10:20:53 AM
   I set the pointer on my scale to show the thickness of the cant/board below so when my marker says 2" there is a dog board exactly 2" thick left on the bed of my mill. I start using this scale on the 4th face and end up with a board exactly the preset thickness desired. 
That's exactly what I want to achieve! Problem is that I'm not used to the imperic system at all, not even a little bit.    
So your sheets look like some calculations from the NASA to me :D But the idea is the same, I will make some excel sheets and check or it works. 
Title: Re: Cheat sheet
Post by: WV Sawmiller on July 20, 2020, 02:11:34 PM
  I built my cheat sheets by starting with the bottom board and adding each additional measurement from there. For example if I am cutting true 1" boards it looks like this:
1
2-1/8 (1+ 1-1/8 )
3-1/4 (2-1/8 + 1-1/8 )
4-3/8 (3-1/4 + 1-1/8 )
5-1/2 (4-3/8 + 1-1/8 )
etc.

for half inch since I have to allow at least 5/8" for clamping I start with a 1" board then:

1
1-5/8 (1+5/8 )
2-1/4 (1-5/8 + 5/8 )
2-7/8 (2-1/4 + 5/8 )
etc.

  Its a bit tedious the first time but I only have to do it once for each thickness then its there for use forever..
Title: Re: Cheat sheet
Post by: Nebraska on July 20, 2020, 02:25:50 PM
2.54
5.3975
8.255

Thats enough converting to cm...I would need stronger readers to see all those little lines on a metric scale. ;)
Title: Re: Cheat sheet
Post by: WV Sawmiller on July 20, 2020, 07:35:58 PM
@Nebraska (https://forestryforum.com/board/index.php?action=profile;u=45256) ,

   Or you could just upgrade to a bigger mill with Accuset II and start on your mark for your bottom board then set the board thickness and hit the "Blade up" toggle and record each number so you know where to start next time.
Title: Re: Cheat sheet
Post by: Haleiwa on July 21, 2020, 07:22:27 AM
To answer your original question,  the scale measures to the bottom of the blade, so the kerf from the top board is already removed in the slab.
Title: Re: Cheat sheet
Post by: Nebraska on July 21, 2020, 10:48:58 AM
Yeah.....I got nearly new round baler and a rake this year. My wife would likely not be too impressed if I brought that up. I must confess to looking at an ad for a nearly new tk1600 just before I logged on.... :)
Title: Re: Cheat sheet
Post by: Resonator on July 21, 2020, 11:40:41 AM
One thing I will do when cutting paneling, is set my crank scale to 10, 9, 8, etc. and get 7/8" boards each time. Fast easy math, and I get an extra couple boards out of a large log instead of cutting 4/4.
Title: Re: Cheat sheet
Post by: jb616 on July 23, 2020, 12:00:12 PM
Not sure how the electronics work as I have the old manual scale on my 1984 LT30. When I am doing the last cuts on cant I adjust my scale whether I am cutting 4/4, 5/4 or whatever thickness so that the marks line up with zero inches. That way all the cuts are the same. I basically work it backwards. 
Title: Re: Cheat sheet
Post by: caveman on July 24, 2020, 06:18:54 AM
Cruiser, when we had an lt-28 with the notched wheel and a pointer (once around the wheel was 2" and each notch was 1/16"), on the fourth cut when making a cant I would wind the head down to the thickness of the bottom board - say 1".  Then, I would raise the head in 1 1/8" increments until I reached a logical opening spot on the cant for the last face.  After that cut, drop the head 1 1/8 (half way around the notched wheel plus two notches - this is where the pointer comes in handy) for each cut.  All of the boards will come out right and no need for a cheat sheet and no missed cuts due to parallax using the ruler scale.  The extra 1/8" accounted for the kerf.

This only took a few seconds and once we started using it this way along with a good log deck we could crank out consistent lumber, considering it was a manual mill.  The first 20 or so hours of running our lt-50 I wanted our manual lt-28 back.  Now, I have grown fond of it.

One other thing I did recently was to make some plexiglass templates with a centerline marked which are the width of the commonly cut dimensional widths (3 5/8", 4", 6 5/8", 8" etc.) so that I can quickly and roughly mark the small end of the logs for the opening cuts and to give me a visual of what I can get out of each log.  This is really handy for me when cutting multiple cants out of a large log.  Many sawyers would not benefit from this but I find it helpful.  The indicated centerline helps ensure the pith is contained in the center of one cant and the adjacent cants are the same distance from the pith.  The templates have holes drilled so they can hang near the front of the mill.

.
Title: Re: Cheat sheet
Post by: offrink on July 24, 2020, 01:15:09 PM
I used some magnetic strips and marked out the correct thickness. Put that over the ruler on the mill and you have every thing I needed. Line up the pointer with the line and make cut.