A guy contacted me about having a load of 6/4 x ~20" x ~10' oak boards resawn into two halves, 3/4 each minus the kerf. Is this a bad idea for one or both of us?
It would be done on an LT15Wide.
If the oak is fully dry it may be much more difficult than if it were green.
I used a dedicated resaw with a carbide tipped band for resawing dry oak.
My experience is most 6/4 lumber that has had a chance to dry will no longer lay perfectly flat on the mill, thus creating variation in thickness when attempting to saw it into two or more boards.
Why don't we use carbide tipped bands for general milling?
That is asking for heartache. First off, don't believe the mill can cut that low without raising the boards off the bed by laying some plywood or some such on the mill bed first. Then, the stresses that you relieve when splitting the 6/4 is going to make some of the pieces unusable, think potato chip. Unless you like to push yourself and your equipment to the limit, and maybe even damage your mill, I would not do it. Sometimes it is better to just say no.
I have tried to resaw on the mill, it didn't work too well for all the reasons people have said. The only way I have really gotten it to work was the one time I had my wife stand on the board and walk on it to keep it flat while I was sawing.
For some reason, we stopped doing it that way. :D :D
I did my first and last resaw job two weeks ago, what a pain, I charged by the hour and still didn't feel like I got my worth, never again,
Quote from: YellowHammer on November 27, 2019, 09:09:07 PM
I have tried to resaw on the mill, it didn't work too well for all the reasons people have said. The only way I have really gotten it to work was the one time I had my wife stand on the board and walk on it to keep it flat while I was sawing.
For some reason, we stopped doing it that way. :D :D
Said the man with the one legged wife... :D
When I saw the OP I was thinking by the time you remove the kerf you are looking at 2 - 11/16" boards. Sounds awful risky especially with 10" oak boards.
I occasionally resaw a slab I cut too thick to salvage another 4/4 board I left in it. As often as not I regret it after as lots of times the slab lifts off the rails giving a thick and board and a 50/50 chance I will knock the set off my blade.
I have my 35 set up as a dedicated re-saw, wide and dry always results in problems / complications. I don't think I would do that job as the results are likely to disappoint the customer.
I'd agree with everyone on the wide boards being sawn thin causing problems. Where I would differ is the resawing method. If you are clamping boards to your bed and sawing them one at a time, it's a good way to cause insanity. Build a jig with hold downs or a weighted wheel. Push the boards through the head like you would with a table saw, it goes fast and works awesome. Do a forum search for the Arky Resaw. Simple, cheap and effective.
Agreed, I would not take that job. I would explain to the customer the perils of trying to do that. If you think you're doubling your board coverage, you're wrong. You'd have a lot of loss. You're 6/4 are not flat to begin with. Since they are wide, they should be flattened first. By the time you do that, you now have probably 1"- 1 1/8" slabs. You might might as well plane them to 3/4 if that is what you want. If you try milling them, they could curl due to residual stress as has been mentioned.
About two years ago, I had to do some resawing(for myself). I had to weight the boards down to keep them flat on the mill while I sawed so that they would be sawed evenly. In this case, it didn't matter if the final board was bowed as it would be screwed in place as a trim board. In your case, it's a wide board, that you need flat. It would not go well at all in my opinion. Planing it to 3/4 would be much better bet. You're not going to get two boards from one, but you'll get one good one.
On the second page of this thread I have a video of how I was resawing.
My resaw thread (http://forestryforum.com/board/index.php?topic=93570.0)
It's a job for a (vertical) band resaw with a hob feed. The feed rolls press the board into the fence and holds it and you get a uniform thickness regardless of any movement in the timber or curvature in the feedstock.
I'm the champion of workarounds for want of the right equipment - but for this job theres no really satisfactory way of doing it right without the right machine.
You could offer to do several of them for him and see how it works out.
Might be a good idea to let the customer know some of the things that "could" happen when taking on a project like that, with no guarantees!
Wood can change it's mind, half way through!
I just did 4" ash into 2" ash. They were 14" wide. He was hoping to get 1.75" when he finishes. He will not get full length, as some are a little skinny now before he planes.
I wish I had straightened them first with the carbide blade, then he would have got a nice 1.5" but he did not want that. I think he will now. :o
I've done that before with mixed results, and usually not good. Got one coming up with a bunch of old full 2" pine he wants sawn in half. I explained in detail until I was blue in the face that it's not a good idea and why, but he insists he wants to try anyway. So...
The one time I did it and it really worked well was with 4/4 cypress using an Arky resaw jig, but it was very well cut, not very wide and it was cypress.
I was asked to resaw pine 6x7 beams into 2x6 framing studs, a few weeks ago.
(https://forestryforum.com/gallery/albums/userpics/19307/20191111_104830.jpg?easyrotate_cache=1573747629)
The pine was old and frozen, but a four degree band worked well. We did a truck load and anther order is coming in a few weeks.
This goes against all the advice given above, but it's what worked up here in the Glaciated North Country. 😆
If you've got the time and inclination, experiment a bit.
I re-sawed some red oak 3"x16"x 10' that was about 20 yrs old. Did it on lt35. I had to weight it down then take a skim cut to flatten it. Then flipped it over and got a couple of 4/4 boards from each one. Most came out good, but some went several different directions. Had to go really slow, took a long time
I always tell them only to expect one decent board from each one put on the mill. It makes me cringe thinking of resawing dry oak that wide. My hourly rate would probably be higher than the customer would be willing to pay. Very time consuming! Not fun!
It all depends on how the resawn wood is going to be used. If he's making pencil boxes or going to machine it to 1/2-9/16 and staple it to the wall is different from expecting more.
The end use is the answer. For paneling, it might work to the customer's satisfaction, not so much for the Sawyer. If the purpose is flooring, quicker, cheaper, better is to buy more oak and plane it to thickness. I will not divulge how I learned this. Regards, Clark
@Pepe_Silvia (http://forestryforum.com/board/index.php?action=profile;u=42198) , did you decide what you're going to do or tell him?
Quote from: Brad_bb on December 02, 2019, 07:28:04 PM
@Pepe_Silvia (http://forestryforum.com/board/index.php?action=profile;u=42198) , did you decide what you're going to do or tell him?
I told him it was ill-advised and probably would waste a board, but if we was set on it (he is) we could try one out and if he's happy with the result then we could do them all.
My plan is use some plywood to shim it up so that the halfway point is above the stops but not so high that the stops are ineffective.
I'll update with the results.
I'm telling you man, make a resaw jig with hold downs and feed the material through the saw, not vice versa like normal.
Got to agree with Barbender. Spend an hour and make an Arky resaw jig. Chain the saw head in place and push the boards through.
I ended up having Rita push the saw while I pushed down on the board with a crowbar. It worked out ok but real slow trying to keep the bar close but not in the mills way.
I did some garden stakes that started a 2"x 6"s and the boards I was given were wavy from 2" to 11/4" to start. I don't like reworking other's work :o .
Quote from: barbender on December 02, 2019, 11:07:03 PM
I'm telling you man, make a resaw jig with hold downs and feed the material through the saw, not vice versa like normal.
Ok, I will take this advise. May have to reschedule because I'm not sure I'll have time, but that's fine.
Quote from: Nomad on December 03, 2019, 08:17:24 AM
Got to agree with Barbender. Spend an hour and make an Arky resaw jig. Chain the saw head in place and push the boards through.
You severely overestimate how fast I can work. ;D The head has lockdowns built in so that should be helpful at least.
Quote from: JoshNZ on November 27, 2019, 08:24:42 PM
Why don't we use carbide tipped bands for general milling?
I did that. was great. Up until I found 2 drywall screws in a 22" walnut. that was a costly mistake.
My most common boards are 1 x 6 oak for fencing. I take as many as I can but always leave a 6x6 which is my second most common. Figure can make more 1x6 from a 6x if needed but not a 6x from a 1x. When I have resawn have learned to take 3/8 inch off the top which curls because dry at surface and still wet interior. Then flip the bottom last 1 1/2 board and take 3/8 outter surface off it as well. End up with five nice 1x6 rather than four nice boards and two potato chips when I tried to get all six. (going after that last one still makes my heart beat even though I know the blade will clear the stops)