logs

[Vicki Hayden]

Hi,
I have about 40 pieces of tree limbs. They are 12 - 18" long and a foot or so in diameter. I made a saw buck and was going to cut 4 sides off to make them roughly rectangular. My thought was to save some storage room by making them smaller and to have less shaving and turning mess when roughing. Also, my lathe is only midi size if that and rocks with larger pieces. My band saw isn't big enough to cut round circle chunks unless they are only about 4" in length so I want to use a chain saw and the sawbuck. Is this just a waste of time? Will it affect the drying process negatively? I seal the ends with paint or wax sealer. Please give any advice.
Thank you,
Vicki

[Bob Bouis]

Cutting 4 sides off a log will almost certainly cause it to crack heavily in pretty short order. If you're cutting turning blanks to dry, you should try to cut them as close to the final size as possible. Smaller blanks are more likely to dry successfully. At the very least make one cut through the pith as well to cut your logs into halves.

Depending on the wood you might prefer to leave it as logs until you're ready to rough turn it. But be aware that most wood will degrade pretty fast.

ETA: In case I wasn't clear, for the most part you can't dry logs. You can only store them until you cut them up or rough turn them. During that time, they'll start to rot and crack and will be bored through by bugs (i.e., degrade). That might be desirable (in the case of spalting) but for the most part it's a ticking clock.

[Vicki Hayden]

So, should I just coat the ends, store them and then use the chainsaw when I'm ready to make something? I will be making smaller items, ring holders, 8" tall snowmen, Christmas ornaments and maybe a couple of small bowls. I like to make Christmas trees too......about 8 - 10" tall.
Thanks again.

[Bob Bouis]

Unless you're roughing the piece out to turn it later, the wood needs to be dry when you turn it.

You'll need to cut the logs into blanks to let it dry without degrading. There are all sorts of intricacies to cutting and drying wood, beyond what I can explain at the moment. I'd recommend you read up on it online. Here's one to start with:

http://c.ymcdn.com/sites/www.woodturner.org/resource/resmgr/FUNdamentals/WFSpecialHerrmann20150903.pdf

Be warned that it's mostly geared toward bowls, which it sounds like you're not.

[Paul Williams]

At the size you are talking about I think you have some options. I would coat the ends of smaller branches, perhaps up to 6 or 8 inches, and then store them as logs in the shade. Larger logs I would cut the length several inches longer than the width, and then cut lengthwise on either side of the pith. Coat the ends and store. I have lots of large pieces of walnut and white oak in my garage that I stored like that. Yes you do loose some to cracking, but that just supplies smaller blanks for smaller projects. The best results are probably achieved by rough turning while green. Coating and storing until dry. Then returning to final shape. The problem with that is it takes a lot of time if you have a lot of wood.

[John K Jordan]

So, should I just coat the ends, store them and then use the chainsaw when I'm ready to make something? I will be making smaller items, ring holders, 8" tall snowmen, Christmas ornaments and maybe a couple of small bowls. I like to make Christmas trees too......about 8 - 10" tall.
Thanks again.

If you want to turn green wood, leave the logs as long as possible. The other John Jordan (the famous woodturner) said he puts the log off the ground in the shade and when he wants to turn something he cuts off about 6" of waste then cuts a blank. I think he only turns green wood.

If you want to turn dry wood, you have to dry it some way. Almost all of my turning is with dry wood, often smaller things like you mention. If you leave the wood in log form it, as someone mentioned, will never dry. However, even with the ends sealed it will probably crack nicely on the ends and/or down the sides, depending on the species and the particular chunk. To minimize major cracking, it is best to at least saw it down the pith.

To get dry wood, I process all log sections into turning blanks, wax at least the ends, and set them on wire shelves to dry. I do this regularly so I have a constant supply of dry wood - the dogwood, persimmon, and some other wood I'm using now has been drying for 6-10 years. Bigger pieces, of course, take much longer to dry. Smaller squares may be dry in a few months or a year.

I don't usually turn big green bowls so I don't waste time and wood cutting out the pith - I just cut along the pith and plan my cuts so any pith is right along a corner of a turning square where it is unlikely to do any damage.

My bandsaw will cut up to 12" so I either stand a short log section on end or a longer piece on its side and cut down the pith. Then I square off into a variety of sizes. I always shave a thin wafer off both ends of each blank and bend to check for checks, even if the log sections were cut recently. Some wood will start to check and crack within hours or even minutes. If I decide to leave some cracks in the blank, say on one end which may end up in a chuck, I highlight the line with a red Sharpie before waxing so I won't be unpleasantly surprised if I miss it years from now. I use 1/2" 3-tpi blades on a Rikon 18" saw.

361583 361584 361585

I write the species and date process on each piece so I can keep up with them.

361586 361587

I have made blanks using hand saws and chainsaw but the bandsaw is far easier and much less wasteful than a chainsaw. If you don't have a suitable bandsaw perhaps someone in your area will cut them up for you. I've processed pickup truck loads of wood for friends and turning club members. They usually want to leave some of the wood for me but I try to be strong - I think I have three lifetimes worth of turning blanks at the moment!

Without a suitable saw you can always use the time-honored method of splitting the log section into turning blanks. A froe is perfect for this. The blanks aren't as pretty on the shelf, impossible with burls and wild grain, and you forgo diagonal grain/figure opportunities, but the pieces will dry nicely and be perfect for spindle turning.

Note that some pieces get waxed on the sides or even all the way around. This can prevent problems, in particular, where heartwood meets sapwood on some species, for example walnut and dogwood. Unfortunately, I don't know how to learn where to wax except from experience. (Wax, such as AnchorSeal, is a better sealer than paint.) BTW, wax, such as AnchorSeal, is a better sealer than paint. Note that if you purchase exotic blanks from a wood dealer it will probably be waxed completely, some is dipped in hot paraffin. This is the best protection but can greatly extend the drying time.

JKJ

[Bob Bouis]

I agree with just about everything John Jordan said, with one caveat: the first cut on a log (splitting it down the middle lengthwise, through the pith) is best made with a chainsaw. It's just safer and easier than trying to do it with the bandsaw. That first cut will give you a reasonably flat surface to rest on the table of your bandsaw (or sled) to do the rest of the cuts. It also allows you to cut larger logs than your bandsaw could otherwise handle.

[John K Jordan]

...the first cut on a log (splitting it down the middle lengthwise, through the pith) is best made with a chainsaw. It's just safer and easier than trying to do it with the bandsaw...

We will have to disagree on that. I think using the bandsaw is safer and easier than the chainsaw and I get better results with less waste. My experience is with hundreds of log sections, working both ways. A log jig/sled for the bandsaw is helpful but I don't use one. And it does, of course, require an appropriate bandsaw.

I didn't make the effort to provide every detail in the earlier message. Here is some more detail.

It is in fact dangerous to cut unsupported wood on the bandsaw. However, it is easy to insure the wood is well supported, even for that long rip cut down the pith. I find it quicker and arguably safer than using a chainsaw. It can also provide a flatter surface than a bandsaw used freehand. It's certainly a bunch quieter than a gas powered saw.

This is what I do to insure the log section is well supported:

1: Insure the piece will sit without rocking with the pith in the center. I set the log on a flat surface and try different positions to evaluate the best position based on where the pith is in the log, what blanks I might try to get, and perhaps which side of the log is perhaps already the flattest. I mark which side I want up.

I trim a flat strip on the bottom side if needed. Some logs will sit flat and take an effort to rock and roll - these need nothing.

I flatten a spot with one of several ways. I keep a SOG hatchet on the wall next to the bandsaw and stand the log on end to trim any irregularities. Test for stability on the workbench. Trimming usually only takes a few seconds and often logs need no trimming. If the log is a problem or needs more than a quick hatchet trimming, I might make a skimming cut with a chainsaw to make a flat side. I keep a Stihl electric chainsaw handy which is perfect for this, even inside the shop.

2: Once the bottom side sits perfectly on the workbench, I usually use a square to draw a vertical line on each end directly through the pith. There are some situations where I choose not to do this. I then use a straight edge and red Sharpie to draw a cut line down the top of the log.

3: I set the log on the bandsaw and for extra security I usually put a wedge on each side, perhaps two if the bottom flat is narrow. This wedge is visible in the second picture I posted earlier. You may also notice that log has a natural flat side which provided excellent support. I may move the wedge(s) as the cut progresses or add new wedges near the blade and let the others fall off the back. Most of my wedges are the waste from cutting round bowl blanks from square stock.

4: Make the rip cut down the center line. The person I learned this technique from didn't even draw a line - he just made adjustments in the cut by eyeballing the line of the kerf behind the blade. (This was from a book - sorry, I forgot the author and can't give credit unless I hunt through my library.)

5: If the log is long and heavy I will have a second person help support the weight at the rear of the bandsaw, or walk around when part way through and complete the cut by pulling, supporting it my self. I've cut log sections well over 24" long this way with zero issues.

Note that this method will give a very flat section on each half unless you are not careful. I can get this much flatter with the bandsaw than with the chainsaw.

6: After the log is split in two, I again use the hatchet to make sure one edge sits nicely against the bandsaw fence if needed, usually just a matter of knocking of a bit of bark. It is sometimes easier to trim a small irregularity or two with the bandsaw. For the piece in this picture, I chose to trim a little more with the hatchet to remove a projection on one end:

361618

7: Make the first flat cut on the opposite edge. This cut is only to get a perfect flat to rest against the fence for the next cuts:

361619

8: After this flat, the rest is straightforward, again cutting through the pith or from the sides depending on what I see in the wood and the blanks I want, spindle, bowl, etc:

361620 361621 361622 361623

9: I then trim the ends square, checking for end cracks as mentioned earlier, wax and dry. Before too long you will have WAY too much dry wood to chose from. A nice problem! These are from my shelf of spalted blanks:

361624

One more thing - some wood (e.g. dogwood, persimmon) will warp and twist significantly and the surface may darken as it dries and obscure the figure. Wax on the sides will also stain some species, further hiding the color/figure. After my blanks are mostly dry, I usually put them back on the bandsaw and make skimming cuts as needed to square them up. This does several things other than make them look pretty: it reveals any drying defects that I either remove or mark for the future. I often slice a thin wafer from the ends to look for end checks (cracks), rewaxing just the end if the blank if needed. Making the warped blank square again makes it easier to mark and mount on the lathe. Cutting clean faces on the sides lets me an others evaluate the color and figure better. I take blanks like this to our club wood auctions and believe me, a square, dry turning blank cleaned up to reveal the wood will bring more money. I read once that every processing step increases the value.

JKJ

[Vicki Hayden]

Thanks! That is very helpful.

[Vicki Hayden]

This is what I was talking about doing, like your pic top right. Only due to my narrow diameter I wasn't cutting out the pith, just making the rectangles. And since my BS is too small for a lot of it, I used the chain saw. Sounds like cutting the pith out part of what stops the sides from cracking? Thank you.

[Vicki Hayden]

Thank you so much for answering and helping everyone.

[John K Jordan]

... Sounds like cutting the pith out part of what stops the sides from cracking?

Some people do cut wood blanks or put the log/limb itself on the lathe with the pith running down the middle or even crossways. This can work well, especially for a hollowed vessel with fairly thin walls and base. The piece is often turned green to finish then left to dry. Some species are better for this than others. With this method you usually just live with or embrace any warpage or out-of-round. A rectangle with the pith in the middle will likely crack as it dries, depending on the species. Note that the wood from different parts of the same tree or different trees of the same species can behave differently. For example, Black Cherry will sometimes begin to crack soon after cutting - best to seal the ends immediately. However, I had to take down one large cherry that for some reason had the most stable wood I've ever seen in cherry. I still have one log section standing on one end out by my hay storage building that has been sitting unprotected in the sun and rain for maybe 6-8 years now. The chunk is getting weathered now and has some tiny end-grain checks on one end, but it just plain refuses to crack! I cut a bunch of big blanks from it and none of them cracked or warped. I wish I'd cut more!

The juvenile wood around the pith is more difficult to dry successfully since it may shrink at a different rate the the rest of the log. For most species, it's not so much cutting out the pith but cutting through the pith which gives parts of the wood that shrink at different rates room to move - that's what minimizes the cracks. When I leave the pith in the wood but running down a corner it lets it move as it will and doesn't hurt anything - even if it cracks there the cracks are not deep radial cracks and the corner is cut off anyway.

Wood, in general, shrinks much more along the rings (tangentially) than it does in the direction from the bark towards the pith (radially). The ratio of the percentage of shrinkage, the T/R ratio, is one metric along with the total volumetric shrinkage that can give you a hint about how much the wood will warp, and perhaps crack. For example, from the Wood Database the numbers for Southern Red Oak are: 4.7%, Tangential: 11.3%, Volumetric: 16.1%, T/R Ratio: 2.4. Compare that to, say, Black Mesquite, a much more stable wood: Shrinkage: Radial: 2.6%, Tangential: 3.5%, Volumetric: 8.5%, T/R Ratio: 1.3

Also, if you cut a small log or limb through the pith and leave the log in a 1/2 round, it has a better chance of avoiding radial cracks that start at the outside since the entire 1/2 can warp to relieve the stress. Dogwood rounds, for example, are horrible about radial cracking - I left one round about 6" diameter and a crack opened up like a piece of pie, probably nearly an inch wide at the bark. Since the wood shrinks so much more tangentially than radially something has to give. BTW, wood shrinks so little along the grain (longitudinally) that it can generally be ignored.

End checks/cracks are another issue. Since the pores of the wood exit a cut end of the log (transverse section) the wood there dries very rapidly and shrinks quickly close to the surface. Since the wood just a little deeper is still wet and not yet shrinking, something has to give so cracks form to relieve the stress. Sealing the wood with wax simply slows down the rate the water leaves the end and allows the internal moisture to more evenly leave the wood. In a lot of species not much moisture gets though the bark. Cutting rectangular blanks and waxing the ends lets the water leave more evenly through the sides and minimizes drying defects. BTW, there are other ways to keep freshly cut wood from cracking: one is called "ponding", simply submerging wood in water. Another it to freeze it.

I suspect you know all or most of this but someone else reading might find it interesting! One of the best references I know of on the structure of wood and how it dries and moves is Understanding Wood by R. Bruce Hoadley. https://www.amazon.com/Understanding-Wood-Craftsmans-Guide-Technology-ebook/dp/B004WYO862 Hoadley is not only a wood expert but a craftsman and much of his writing is done with other craftspeople in mind.

JKJ

[Damon McLaughlin]

My process varies depending on wood species and sometimes my motivation. I have some very wet elm and cottonwood that are in huge log chunks, for those I keep the wood in log form with the ends sealed and cut off what I'm willing to work with that day. The elm I turn to a very thin final shape and finish with oil, it makes for great slightly warped bowls and I haven't had any crack yet. The cottonwood I rough turn, seal and wait to dry. For my spalted birch I cut those into spindle and bowl blanks, seal and am waiting for them to dry, though I've also had some success in being able to turn to a finished product with no issues. The black locust I prefer to turn green as it turns much easier than when it is dry. The wood is very dense that I can turn to a final product and it won't warp or crack. For the black locust I just cut off what I want to work with that day. Those logs I don't even seal, the checking has never gone more than an inch from the end.

My logs pieces that are big and heavy I split with a chainsaw, smaller more manageable sizes I use the bandsaw to split down the middle.

[Randy Heinemann]

What size bandsaw do you have? I wouldn't think this would be practical on a 14" bandsaw, so I am just guessing but you probably own an 18" or 20".

I know Stockroom Supply sells a bandsaw resawing jig that is meant for sawing up logs, but I would be concerned about using it for a log that is 12" in diameter; 6" or 8" in diameter maybe.

Just asking so that I don't attempt something I think is possible when it isn't with my 14" bandsaw.

[John K Jordan]

What size bandsaw do you have? I wouldn't think this would be practical on a 14" bandsaw, so I am just guessing but you probably own an 18" or 20".
I know Stockroom Supply sells a bandsaw resawing jig that is meant for sawing up logs, but I would be concerned about using it for a log that is 12" in diameter; 6" or 8" in diameter maybe.
Just asking so that I don't attempt something I think is possible when it isn't with my 14" bandsaw.

Before I got my current bandsaw I used a 14" Delta I bought new around 2000 or so. I put a riser block on it to give a 12" cut. I tell you fact - I processed a bunch of green wood with that saw using the same techniques I use today (but a little less refined!) The Delta was relatively under-powered (3/4 hp?) but it handled anything that would fit on it, although perhaps not real fast. With sharp blades and a controlled cut the saw never bogged down, even with hard woods like osage orange and dogwood. I experimented with a bunch of different blades on that saw from 1/2" to 1". The larger blades worked but were pushing the limits of the saw. I settled on 1/2" 3-tpi blades.

The Delta with the riser block was fine for resawing as well, as long as I didn't get in a hurry. My biggest resaw project was when a friend brought over a 12' long 2x12 Douglas Fir board which we resawed into four thin boards so he could case in a post in his house. (To this day I can't imagine how I managed to do that successfully!) I mention this only to confirm that the 14" saw is certainly capable of more than some use it for. A caveat - I did tune the saw carefully, shim the wheels to co-planar (regardless of what Snodgrass says) and made sure the blade always tracked right in the center of the tires both top and bottom, beefed up the tensioning spring, added a quick release arm (I always release the tension when not in use), added blade/wheel brushes inside to keep gunk off of things, and bought a tension gauge to make sure the tension was right with no guessing. This saw was probably good for me to learn on, teaching fineness instead of force. I also learned to resharpen the blades myself since very sharp blades are important for big wood and since I was too cheap to buy new blades all the time.

My current bandsaw is an 18" Rikon, 220v, with more power (2 or 2-1/2 HP I think) and stronger frame. However, the maximum work height is the same as the Delta - about 12". I still use 1/2" 3-tpi blades for all my green wood processing. This saw has a lot more power than the smaller Delta, a larger table, and far better dust collection, but it's really no different in cutting up green log sections except it will cut a little quicker if I push it. However, I don't get in a hurry processing wood. To me it is a relaxing, enjoyable time with big rewards - start with a piece of almost worthless firewood and end up (eventually) with something quite useful to me or someone else. And I have plenty enough wood to give away to spread the joy around!

As I mentioned, I don't use any kind of sled or jig. I thought about it but never got around to making one. I might if I got into slicing up logs into thin boards. The method I use works fine and needs nothing but a fence.

JKJ

[Vicki Hayden]

I only knew a bit of this. Thanks so much for the great info!

[Vicki Hayden]

I have a 10" Craftsman BS.

[Vicki Hayden]

10" Craftsman.