Poor man's "setworks"

[alecs]

I'm new to running my mill (Woodland HM130), and I don't really trust my eye yet on looking at the log scale.  So I have been measuring cuts with a tape measure before cutting to see that I am getting consistent boards.  That has had the predictable result of getting sap all over my tape measure (cutting pine).  So I came up with these little guides.  I laser cut some acrylic pieces, with a different piece for each board thickness, the idea being to put the long end on top of the cant and line up the blade with the stub end to determine the blade height when running each cut.

Thoughts?    

I'll try and get a couple of photos of them in use once I try them out.  In the meantime, working on designing a tag axle for bringing long logs out of the woods.



 



 

[Crusarius]

Thats a pretty sweet idea. I am starting to lose my touch identifying steel thicknesses from across the shop. I may need to make some of those for steel thickness.

[btulloh]

I find gauge is very helpful also. Making consistent Lumber is a good thing to do. I also made up a chart that shows how many clicks or holes it takes to make a certain thickness. You’ll probably want gauges for both hardwood and softwood scales also.

I saw a lot of pine for framing and I have a chart and gauges that help me to cut pine slightly oversize so that it dries and shrink to match store-bought thicknesses.  For instance to get a 2 x 4 that matches store-bought I’ll cut pine 1 9/16 thick by 3 5/8 wide. Even allowing for differences in shrinkage because of tangential versus lateral shrinkage and the way it varies as your Cutthrough account they still come out pretty consistent and can be mixed in with store-bought when necessary.

Anything that helps make more consistent Lumber is a good thing.

[Hilltop366]

The inconsistency in using your eye on a scale can be overcome, a great idea that I had seen here on the Forestry Forum was to have two pointers or lines stacked so you had to line up the pointers with your eye while you read the scale.

This eliminates the errors by having your eye at the same level every time in order to get the pointers lined up.

[moodnacreek]

So that's how you set , by eye. It can be done, is done and I used to do it also but it is not what you really want. Something mechanical like a screw with a hand crank [ one turn to the inch kerf included] or rachet or pin stop or detent any thing so youdon't have to look at the scale.

[ljohnsaw]

This eliminates
the errors by having your eye at the same level every time in order to get the pointers lined up.

That's called a parallax error.  The best way to overcome that (short of counting/mechanical - but that can have errors as well) is to use a laser line.  Like this:
 

 The red line is actually sharper and thinner then the picture shows.

[fluidpowerpro]

Similar concept to ones I have made using thin aluminum strips. I drill a series holes in them to correspond to board thickness plus a bit for kerf and drying. The mark on the wood is made with a sharp tipped sharpie through the hole.

 

 

 You can use them starting from the top or bottom edge of the can't.

[chet]

This may be what was Hilltop366 was referring to eliminate parallax error.  
I used a piece of 1/4" Plexiglass and put a permanent red line on both sides for my sight line. If you look at it straight on you see one line,  otherwise you will see two red lines.  The faint red line you see underneath is the shadow that the camera picked up.

[Hilltop366]

Yes, thats what I was thinking of, I was also wondering what effect the distance between the two lines has. Just holding up my fingers or two business cards to try it seems like the more distance the more accurate it would be....or it could be my imagination.

[chep]

I love the idea of gauges. I run a Lucas mill and the parallax stuff gives me fits on the provided scales. Anyone running a Lucas figured out how to improve the stock scales ?

[DixieReb31]

alecs, Do you place the gauge before every cut?  

[chet]

With the 1/4" between the two lines it is dead on. Before I put the second line on the backside, the reading I would see on the scale could very by as much as 3/8".

[NOCO Jim]

What about those cheap digital readouts?  Anyone have success with using one?

[KirkD]

What about those cheap digital readouts?  Anyone have success with using one?

I mounted one last summer and used it a bit but need to improve my mount as I offset it to leave the stock readout in place. I like how I can zero it after a cut and then go right back to zero at the start of another cut then drop down the amount I want to. I think it will work fine when I get it on a permanent mount.
This is what I got but I am pretty sure mine is longer than 24" I will measure it later.
DRO
I also want to make it removable so I don't have to leave it out in the weather when I am ot using the mill.

[alecs]

alecs, Do you place the gauge before every cut?

I haven't actually had a chance to try it out yet.  Placing before every cut was my plan.  

I've been taking a step back to try to get my track and bunks a little more accurate based on some cuts that I made last week.  In those cuts, I'm not quite sure how I did it, but I made more than one 2x8 that was 2" on the money on either end, but almost 2 1/4" in the middle.  But the 8" was consistent along the whole length of the board.  I'm still trying to replay in my mind what I did that would have caused this issue.  Might have been operator error, but my first thought was to check the setup of the track, bunks, saw carriage, etc. to make sure everything was aligned properly.

What about those cheap digital readouts?

This was sort of the direction I was heading in, but I was thinking about trying to do it with a different kind of sensor.  I wanted to be able to set it up to simultaneously tell how thick of a cant was left on the bunks as well as how thick of a board I was about to cut.  

I might first try the parallax-eliminating indicator design and see if that gets me where I want to go.  With the design of the Woodland Mills unit, the log scale sits up pretty high, and with the unit on its trailer (vs. on cribbing on the ground) it is not possible for me to look at it straight on.   

I will update the thread as I go in case there is something useful I come across.

[Hilltop366]

I made more than one 2x8 that was 2" on the money on either end, but almost 2 1/4" in the middle.

It is good to check the mill.
It is also likely that the can't bowed. Stress in the log.
Watch the log on the bunks after a cut, it can bow either lifting the ends of the log = next cut will be thin in the middle or lifting the middle = next cut will thick in the middle.

Try searching for "stress in log" or something along those lines for info.

[alecs]

Thanks for the reminder about the cant potentially bowing!

I made a clear acrylic pointer to replace the red metal pointer that came on the mill.  Here it is installed.  It is definitely easier to see what is going on with this one compared to the factory part.

I tried scoring the indicator line on both sides of the acrylic to see if it would make a difference, but the acrylic is only 1/8" thick and I can't really tell what line is on what side of the new pointer.  I think it would actually work OK if the acrylic was practically touching the log scale, but that might make it harder to move or remove the magnetic scale.

I think the linear DRO that NOCO Jim suggested might mount easily though.  Might give it a try. 





 

[chet]

It doesn't matter what line you see. The whole idea is when you look straight on (eliminating the parallax error)  you will see only one line. A fine permanent marker high lighting your score will help also.

[ljohnsaw]

This is what I got but I am pretty sure mine is longer than 24" I will measure it later. DRO

What is the rule made out of?  The listing says you can cut it to any length.  Wondering if you can substitute a metal yard stick so you can have more than 24".

[Vautour]

What about those cheap digital readouts?  Anyone have success with using one?

I've been looking at them and will be installing one soon,Norwood has them on some of there mill,.. Amazon  (600 mm 23.76'') in length at $75.00 + shipping.