Setting Up Initial Cant - How Much To Slab Off?

lxskllr · July 13, 2019, 08:36:10 AM

Mentally prepping for getting my Alaskan setup, and I'm wondering about the slab cuts, with dimensional lumber as the end product. The little manual the Granberg came with shows very little coming off the small end of the log. Looks like it's just taking off the cambium layer. I'm having some trouble wrapping my head around that. Do I want to do that, or set it up to get the largest true square possible from the log?

WV Sawmiller · July 13, 2019, 08:54:53 AM

I don't know why it would be different with an Alaska mill but the thickness of my first cut is based on the width of the face I want to open. The difference between getting a 4" face and a 6" face is often only about half an inch thicker opening cut. I would think because of the extra work involved between cutting with a CSM or a bandmill I'd be inclined to slab a little deeper to make sure I hit my target width. Good luck.

Southside · July 13, 2019, 11:09:22 AM

Just keep in mind your best lumber comes from the jacket boards, so the more you slab off, the less value you recover from the log. Personally I cut just the bare minimum on the small end, sometimes if the log has a hump (talking pine here as with hardwood it would be different) I will end up with several shorter boards at first to result in less of a opening slab as the full length cut does not actually start at the small end but rather part way down the log for a few cuts. I realize things are significantly more difficult with a CSM so you will have to weigh that out.

Magicman · July 13, 2019, 11:31:51 AM

Never make the initial cut or any other cut without knowing where your target is within the log. Kinda like a roadmap. Know where your destination is before you leave home.

YellowHammer · July 13, 2019, 11:45:14 AM

CSMing is tough, get the good wood first, then the lower grade.

moodnacreek · July 13, 2019, 12:52:34 PM

What is CSM, is it circle saw mill?

lxskllr · July 13, 2019, 12:56:02 PM

ChainSawMill

Oddman · July 13, 2019, 01:41:29 PM

You have probably seen pictures or video of the end of a log marked up to show where each cut will be made to make it into the desired lumber...that's basically the roadmap that magicman mentioned. Take some time with a framing square and a pencil to map out the cuts you want to make on the small end of the log. Remember to allow for kerf.
Do this for a while and you will probably be able to get a mental image of the map without needing to mark it out.
I didn't bother with this when I started and I wasted a lot of time making shim cuts to whittle the cant down to my desired size. With an Alaskan I guarantee you do not want to make any wasted cuts...
Good luck.

LeeB · July 13, 2019, 03:55:29 PM

Quote from: Magicman on July 13, 2019, 11:31:51 AM
Never make the initial cut or any other cut without knowing where your target is within the log. Kinda like a roadmap. Know where your destination is before you leave home.

Very true. And like a road trip, your starting point depends on your needs. Are you looking for utility, quality, or quantity.

Don P · July 13, 2019, 05:48:58 PM

Somewhat deeper than the screws used to hold the guide, especially if they are those really good hardened screws.

btulloh · July 13, 2019, 06:01:21 PM

Quote from: Don P on July 13, 2019, 05:48:58 PM
Somewhat deeper than the screws used to hold the guide, especially if they are those really good hardened screws.

!!!! True dat!
It's amazing how fast "out of sight, out of mind" can take over in a situation like this. I've sawed right into a timberlok or two immediately after putting them in to hold something I was working on. There was very little damage to the heads of the timberloks. :D :D I wasn't setting up a CSM cut, but it was a similar situation. It took a lot of filing to get the chain back.

Southside · July 13, 2019, 08:01:59 PM

It should be illegal for the general public to possess hardened screws. :D

Tom the Sawyer · July 14, 2019, 12:19:52 AM

Probably not applicable to a CSM but, since my offbearers are almost always my clients, I consider the weight of the slab, and their ability to handle it. I would much rather take 30 seconds to make an extra cut and take it a bit easy on the offbearers, I need them to last to the end of the day.

WV Sawmiller · July 14, 2019, 07:05:24 AM

Tom,

Very good point. Last Tuesday I was cutting for a client who had some very large and some real crooked pine and maple logs requiring some deep heavy cuts to get the face we needed and I was generating some heavy first cut slabs and would have to help my helper carry them to the slab pile. It was very hot and by the end of the day I was making an extra cut or two to reduce the weight of those scrap slabs so he could handle them alone. It did not take me any extra time and saved a little wear and tear on both of us. If I'd been using a CSM the sawing would have been more work than toting a heavy slab.

JohnW · July 14, 2019, 11:23:44 AM

lxskllr, I'd say your idea to go for the largest square with your first cut is right for a csm. If you think there's a good board in the slab you cut off, turn it flat side up and mill it. Check out Will Malloff's book, Chainsaw Lumber Making. You can probably read it online some place.

WV Sawmiller · July 14, 2019, 05:05:00 PM

John,

I have and still occasionally try to recover an extra board out of a first cut slab like you mention when I think I cut too deep. However if I put the slab back on the mill and it wants to curl up at one or both ends, which they often do, I generally just toss it as I know at best I am going to get a thick and thin board. Usually the juice just ain't worth the squeeze in such cases and, because such slabs don't clamp well and are so close to the dogs when trying to recover that last 4/4 board, I am sure I have broken or knocked the set off more blades than the actual lumber value I recovered when the slab jumped out of the clamp and ruined a blade or I got so close I nicked a clamping dog and at least knocked the set off a few teeth. It might work better with a CSM since it is following the curve of the wood when you are guiding off the previously cut piece/side instead of following the rails on a bandmill. I am not a CSMiller but I still think I'd be awful inclined to slab deeper if I were. I just can't see making many trim cuts with a CSM. JMHO.