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General Forestry => Sawmills and Milling => Topic started by: Quebecnewf on April 15, 2017, 04:57:52 AM

Title: A clamping question
Post by: Quebecnewf on April 15, 2017, 04:57:52 AM
This is kind of difficult to explain but here goes.

I am sawing a fairly large ( for me ) order of 4x4x12 and 2x4x12 . I am having some issues with the length and suppleness of the cants once I slab them three sides. They have a tendency to not want to lay flat on the bunks. My question is there someone out there that has a type of clamp made that is sort of two stage. First stage it clamps into the can't and then second stage is a clamping stage that pulls the can't down to the bunk. This I know would only work for small cants like 4x4  but would be a good option for any small springy wood.

Sorry if the question is a bit vague ..
Any pictures of such would be great

Quebecnewf
Title: Re: A clamping question
Post by: bandmiller2 on April 15, 2017, 06:49:27 AM
A two plane clamp would do what you want, but with that stress your finished pieces will look like an archers bow. I don't mess with them but theirs guys here that know how to handle stress. Frank C.
Title: Re: A clamping question
Post by: kelLOGg on April 15, 2017, 07:03:38 AM
I first tried this.
https://forestryforum.com/board/index.php/topic,53297.msg769079.html#msg769079

and then made this.
https://forestryforum.com/board/index.php/topic,71122.msg1068700.html#msg1068700

Orient the cant so you get bow and not crook. The lumber is still unavoidably bowed but is uniformly thick and more usable in construction where you can use nails or cross-bracing to hold the lumber straight.
Title: Re: A clamping question
Post by: rl on April 15, 2017, 07:31:46 AM
I see that often when sawing any size..4x12 the 12 probably does not bow?  the 4 cut does  if I catch it I cut the amount of bow over sized  [4 1\2 ] or 4 3\4 that side might be straight..then flop 180 degrees and cut at 4"..a pain but usually works   rl
Title: Re: A clamping question
Post by: Ga Mtn Man on April 15, 2017, 10:09:03 AM
Something like this maybe?  Look at 2:45 into the video.

https://youtu.be/zlc9Ykixzeg
Title: Re: A clamping question
Post by: Sixacresand on April 15, 2017, 10:14:13 AM
Quote from: rl on April 15, 2017, 07:31:46 AM
I see that often when sawing any size..4x12 the 12 probably does not bow?  the 4 cut does  if I catch it I cut the amount of bow over sized  [4 1\2 ] or 4 3\4 that side might be straight..then flop 180 degrees and cut at 4"..a pain but usually works   rl
I have tried to stand on bow to press it down and pull the clamp lever with a rope to hold it down.  Most of the time my 250 is not enough.😅
Title: Re: A clamping question
Post by: Ga Mtn Man on April 15, 2017, 10:26:02 AM
Here's a better video.  See time 2:35.

https://youtu.be/3qeLALgC6fI
Title: Re: A clamping question
Post by: Quebecnewf on April 16, 2017, 05:51:06 AM
Thanks for the replies . I like the screw type pull downs that Kellogg fabed up with his welder . They do the job that I need done. My concern is they look a little cumbersome to work . Reaching down under the bunks to screw them up plus having to tap them into the can't ' . Good rig if you have to do it on only a few logs . My concern is that with this order of approx 200 logs , most of which would need this dogging down done to them it would be slow . Still an option though.

The Woodmizer system is great but hydraulic powered so not an option for my mill. If there was a clamp like that exactly but powered by a lever . In other words you would slide the clamp along and drive it into the can't and as you pushed down on your lever it would drive into the can't and pull down. Even just a 1/4" haul down would solve the problem 90% of the time.

I know in the amount of knowledge that is represented here on this forum there is design sitting in the back of someone's mind.if we could get something like this designed I can see where many Sawyers would adept it to their mills.

Let's put on our thinking caps ......

Quebecnewf
Title: Re: A clamping question
Post by: Peter Drouin on April 16, 2017, 07:47:08 AM
I put fangs on my clamp, Works good if you're careful not to rip the cant up.
With the back stops up a little I clamp, Pull down some with the clamp then go down with the back stops some and the wood is down to the bed .


 (https://forestryforum.com/gallery/albums/userpics/22511/mill_clamp_062~1.JPG?easyrotate_cache=1323130190) 
Title: Re: A clamping question
Post by: Magicman on April 16, 2017, 09:34:35 AM
With a bowed cant I sometimes have to resort to using this:


 (https://forestryforum.com/gallery/albums/userpics/20011/DSCN0375.JPG?easyrotate_cache=1366846513)
I turn the hump up, squeeze the cant down to the sawmill bed with this oversized C clamp, clamp it with the sawmill clamp, and then remove the C clamp.
Title: Re: A clamping question
Post by: Kbeitz on April 16, 2017, 09:50:30 AM
Quote from: Magicman on April 16, 2017, 09:34:35 AM
With a bowed cant I sometimes have to resort to using this:


 (https://forestryforum.com/gallery/albums/userpics/20011/DSCN0375.JPG?easyrotate_cache=1366846513)
I turn the hump up, squeeze the cant down to the sawmill bed with this oversized C clamp, clamp it with the sawmill clamp, and then remove the C clamp.

And here I was thinking that you dint have anything made in China...
Title: Re: A clamping question
Post by: Ox on April 16, 2017, 10:32:55 AM
 :D  I wonder if it's actually unavoidable today, K.
Title: Re: A clamping question
Post by: Magicman on April 16, 2017, 05:34:47 PM
Didn't come from China......it came from Harbor Freight!   ;)  :D
Title: Re: A clamping question
Post by: Kbeitz on April 16, 2017, 05:47:47 PM
Quote from: Magicman on April 16, 2017, 05:34:47 PM
Didn't come from China......it came from Harbor Freight!   ;)  :D

yep... Your right China... :D
Title: Re: A clamping question
Post by: Quebecnewf on April 16, 2017, 06:58:46 PM
That clamp would do the job . Screw down the cant then dog it and remove the clamp.

Now come up with the same idea but positioned below the cant . Part of the clamping system . Will not have to be removed before you pass the saw and is lever based not screw.

Easy to type maybe harder to design ..

Quebecnewf
Title: Re: A clamping question
Post by: Magicman on April 16, 2017, 07:50:38 PM
Suction from below?  OK, try one of these:  LINK (http://www.houzz.com/photos/35379680/Toilet-Plunger-traditional-toilet-plungers-and-holders)   :D
Title: Re: A clamping question
Post by: Quebecnewf on April 18, 2017, 05:11:56 AM
Did some more poking around and found this ( in my own Provence no less)

http://www.vieltools.com/detail.php?p=MTUzOA==

There is a short video in French but if you notice in the video as the clamp moves ahead it also forces down maybe 1/4" . I think these guys have nailed it. All the other lever clamps I have seen only dog the cant sideways . This one because of the way it is built pushes both sideways and down. It's a winning design . now if only it did not cost 299.00 dollars.

https://m.youtube.com/watch?v=djlUXggHuHU&ebc=ANyPxKpdHmH7-homCFyp4CeshBdFjhn0dz41q8V3iN6rVGMnfMXTHFLx2QZILuVmrKbrb7PBr8si2MHMr6JwP7sN3dZ1NbfJEw

This clamp is designed as a retrofit on this mill which is also built in Quebec. The clamping system that this mill comes standard with is not to shabby as you can see in this video. I have checked out these machines myself ( their main retail store and factory are in Quebec City). They are well built and very well engineered machines. The controls are second to none ( notice in the video how quick he can raise and lower the head all Manuel )

To all you US guys up near the border you would do well to check out these machines. With the difference in the Canadian and US dollar this one is a winner. The best mill you will get at the best price. IMHO

Quebecnewf
Title: Re: A clamping question
Post by: 4x4American on April 18, 2017, 06:06:55 AM
You have stress in the piece you need to balance it. Just last week I was sawing a customers logs who wanted "as many 4x4's as possible out of each log".  They are young black birch logs.  After explaning to him til I was blue in the face why that is a bad idea, he gave executive orders to do it anyways.  So I cut to an oversize cant maybe 11x11 and then split into quarters.  I got 5.5x5.5" pieces that had twisted and looked like pasta noodles.  So the problem here is you cant just cut willy nilly because it will come out wicked thin.  I marked on the wood for a visual where 4x4 would be.  The trick is to clamp it without pulling it down.  If you pull it down it will spring back out after you release. You need to saw it how it sits.  Just have at it and keep flipping it.  Saw the belly then the ears then back and forth and back and forth.  After working the cant for a bit, get it back to square and only take 1/2" cuts or less.  It is alot of fiddle-farting around but he wanted it and job was by the hour.  What a pain, I got some straight 4x4's though that were 4" the whole way.  My worker thought it was magic 😂
Title: Re: A clamping question
Post by: Ox on April 18, 2017, 12:06:08 PM
I like that mill, Quebec.  It looks easy to use and well built and thought out.  I'd buy one.
Title: Re: A clamping question
Post by: rl on April 18, 2017, 01:31:11 PM
  all good options.....but if you want it to still be straight when you take it off mill [by itself] you need to let it do it's thing's before actual sizing
Title: Re: A clamping question
Post by: Quebecnewf on April 18, 2017, 08:43:33 PM
The discussion is about clamping not about how to saw out a 4x4 . Let's do that discussion on another thread .

Quebecnewf