By swirt on June 28, 2010
I had a need to take relatively small diameter (~8″) logs and mill them into lumber. I have a lot of fallen cedar trees in the area and I wanted to be able to mill some logs for use. I researched a lot of bandsaw sleds for re-sawing, but they all seemed to have the limitation of only being able to do either long lumber or short lumber. They did not do the full range. So I had to get a little creative.
The solution I came up with is pretty simple, very flexible, and very inexpensive. It does lack precision, so it is not intended for resawing veneer or final dimmensioning of lumber.
This shows the pipeclamp in place on the bandsaw milling sled.
Bandsaw Mill Sled Design
The sled is made using a pine 1×8″ (or wider based on your bandsaw). Ideally the width should be larger than whatever the distance is from the edge of the blade to the inside edge of the miter slot on your bandsaw table. The first time you run the sled through, it will trim the sled to the perfect width. I recommend pine because it is light yet stil strong. Being inexpensive doesn’t hurt either. I made mine 8′ long because that was the maximum length that I could forsee myself cutting. In reality you can can actually cut a log a few feet longer than the sled by having the pipe run longer. The edge of the sled that is farthest from the blade gets a runner glued and screwed in place. The thickness of the runner will have to be adjusted to match the width of the miter slot on your bandsaw. I made mine out of Douglas Fir because pine is a bit too soft.
This is the tail end of the sawmill sled. You can see the main board with the runner on the right edge. Notice that the pipe clamp saddles have one screw in the runner and one in the board.
The log is secured using a Jorgensen Deep Reach pipe clamp, a 3/4″ steel pipe. Ordinary pipe clamps will not have enough reach to secure a log(because the log is round) but may be used to secure already square stock. There is also an extra deep reach pipe clamp you can get if you have a very large bandsaw. I have one of these large clamps, but it is too big as it could actually come into contact with the blade of my saw, so I don’t use it.
The pipe is secured to the sled using Jorgensen pipe clamp saddles. The saddles are aluminum and have a thumbscrew to secure the pipe. This is handy because the pipe can easily be swapped in and out for different lengths as needed. I usually use a 6′ piece and add a 2″ extention if needed. For my 8 ft sled I used 6 saddles (1 every 18″) but if you wanted to be assured of less deflection of the pipe, you could use more. Keep in mind that you have to slide the pipe out of the saddles in order to move the clamping head if you are moving it more than the distance between the saddles. So adding more saddles makes it more difficult to adjust lengths.
Reinforce your Rollerstand
The wood of the sled and the pipeclamp makes the sled fairly heavy. Combine that with the log you are trying to mill and the weight can get pretty significant. You definitely need some kind of roller stand both in front of the bandsaw and on the outfeed side. I quickly found that my roller stands were not strong enough to stay horizontal. The weight of the log is usually not centered on the roller so it would tilt the roller.
For cutting large logs, it is important to reinforce the squareness of the roller. Position is important. Notice the sled runner is alinged to miss the edge of the roller.
I solved this issue by simply bolting some square cut braces of wood to the roller assembly. Overall, rollerstands like this are a pain in the neck because they need to be at a right angle to the path of the sled in order to keep it rolling straight. The weight of the wood and the weight of the sled make this even more pronounced and can lead to binding the sled in the miter slot. Ballbearing based roller stands are a much better choice. In the photo above, note that the edge of the roller needs to just miss the runner so that the flat bottom of the sled is the only part making contact with the roller.
Bandsaw Sawmill Sled in Use
To make the sled more functional I used a combination square and a pencil to run pencil lines down the entire lenght of the sled. I spaced them 1/2″ apart. These become my reference lines for the cutting. When I orient the log for the first cut, I mark the center of each end with a pencil. I then align this pencil mark on each end with a specific reference line on the sled. Which line is not that import, it just has to be the same line.
In this photo you can just make out the pencil lines that run the length of the sled. Notice also that unlike ordinary pipe clamps, the clamping head slides instead of the tail.
I first align the tail end of the log to a specific line, then go align the other end, then go back and see if the first end moved. It almost always moves a little bit. After a few adjustments I can tighten the clamp down and secure the log. Due to a little bit of flex in the iron pipe, the front end of the log almost always shifts a bit toward the blade. Typically about 3/8″ for a 6 foot log. The longer the log, the more it will shift. I try to take that into account when I align the front and actually plan it so that when I tighten the clamp it shifts out to where I want it. It sometimes takes a few attempts(nothing major).
The sawmill sled is ready for the first cut on the log.
From here, I turn on the bandsaw and start pushing the sled through. The sled is almost an inch high, so it reduces the amount of resaw capacity on your bandsaw by just under an inch. My bandsaw has a 8-1/2″ resaw capacity, so the biggest log I can mill is about 7″ in diameter.
Here the cut is quartering, half a log.
When the first cut is done, I unclamp the log, move the sled and log back to the starting position, then put the newly cut edge face down on the sled. I again use the pencil mark indicating the center of the log to align the log with the reference lines. I then push the sled through again. Now I have two faces at right angles to each other. At this point I can use the sled to cut off a slab of whatever thickness I want.
Safety Concerns
Safety glasses and hearing protection are a must
When pushing the sled from the back, I always push by putting my hand onto the tail-piece of the clamp. The clamp can’t contact the blade, so neither can my hand.
Since logs are round, you have to be careful not only of the blade entering the log at the top (usual concerns for a bandsaw), but you also have to watch out for the blade exiting the log because the log is not flush to the table.
I keep a couple of shims and a mallet handy and drive a shim into the end of the log once I am a foot or so in. This helps prevent the blade from binding in the kerf and stalling the saw.
Density of logs can vary within the log. It can be dense and slow cutting in one section then go into easy cutting punky stuff without warning, so don’t push too hard on the sled AND keep aware of where your hands would go if the log slipped. Keep them out of the path of the blade.
For my uses (not fine furniture) this sled makes it pretty easy to turn small logs into lumber, and that makes me happy.
I had a need to take relatively small diameter (~8″) logs and mill them into lumber. I have a lot of fallen cedar trees in the area and I wanted to be able to mill some logs for use. I researched a lot of bandsaw sleds for re-sawing, but they all seemed to have the limitation of only being able to do either long lumber or short lumber. They did not do the full range. So I had to get a little creative.
The solution I came up with is pretty simple, very flexible, and very inexpensive. It does lack precision, so it is not intended for resawing veneer or final dimmensioning of lumber.
This shows the pipeclamp in place on the bandsaw milling sled.
Bandsaw Mill Sled Design
The sled is made using a pine 1×8″ (or wider based on your bandsaw). Ideally the width should be larger than whatever the distance is from the edge of the blade to the inside edge of the miter slot on your bandsaw table. The first time you run the sled through, it will trim the sled to the perfect width. I recommend pine because it is light yet stil strong. Being inexpensive doesn’t hurt either. I made mine 8′ long because that was the maximum length that I could forsee myself cutting. In reality you can can actually cut a log a few feet longer than the sled by having the pipe run longer. The edge of the sled that is farthest from the blade gets a runner glued and screwed in place. The thickness of the runner will have to be adjusted to match the width of the miter slot on your bandsaw. I made mine out of Douglas Fir because pine is a bit too soft.
This is the tail end of the sawmill sled. You can see the main board with the runner on the right edge. Notice that the pipe clamp saddles have one screw in the runner and one in the board.
The log is secured using a Jorgensen Deep Reach pipe clamp, a 3/4″ steel pipe. Ordinary pipe clamps will not have enough reach to secure a log(because the log is round) but may be used to secure already square stock. There is also an extra deep reach pipe clamp you can get if you have a very large bandsaw. I have one of these large clamps, but it is too big as it could actually come into contact with the blade of my saw, so I don’t use it.
The pipe is secured to the sled using Jorgensen pipe clamp saddles. The saddles are aluminum and have a thumbscrew to secure the pipe. This is handy because the pipe can easily be swapped in and out for different lengths as needed. I usually use a 6′ piece and add a 2″ extention if needed. For my 8 ft sled I used 6 saddles (1 every 18″) but if you wanted to be assured of less deflection of the pipe, you could use more. Keep in mind that you have to slide the pipe out of the saddles in order to move the clamping head if you are moving it more than the distance between the saddles. So adding more saddles makes it more difficult to adjust lengths.
Reinforce your Rollerstand
The wood of the sled and the pipeclamp makes the sled fairly heavy. Combine that with the log you are trying to mill and the weight can get pretty significant. You definitely need some kind of roller stand both in front of the bandsaw and on the outfeed side. I quickly found that my roller stands were not strong enough to stay horizontal. The weight of the log is usually not centered on the roller so it would tilt the roller.
For cutting large logs, it is important to reinforce the squareness of the roller. Position is important. Notice the sled runner is alinged to miss the edge of the roller.
I solved this issue by simply bolting some square cut braces of wood to the roller assembly. Overall, rollerstands like this are a pain in the neck because they need to be at a right angle to the path of the sled in order to keep it rolling straight. The weight of the wood and the weight of the sled make this even more pronounced and can lead to binding the sled in the miter slot. Ballbearing based roller stands are a much better choice. In the photo above, note that the edge of the roller needs to just miss the runner so that the flat bottom of the sled is the only part making contact with the roller.
Bandsaw Sawmill Sled in Use
To make the sled more functional I used a combination square and a pencil to run pencil lines down the entire lenght of the sled. I spaced them 1/2″ apart. These become my reference lines for the cutting. When I orient the log for the first cut, I mark the center of each end with a pencil. I then align this pencil mark on each end with a specific reference line on the sled. Which line is not that import, it just has to be the same line.
In this photo you can just make out the pencil lines that run the length of the sled. Notice also that unlike ordinary pipe clamps, the clamping head slides instead of the tail.
I first align the tail end of the log to a specific line, then go align the other end, then go back and see if the first end moved. It almost always moves a little bit. After a few adjustments I can tighten the clamp down and secure the log. Due to a little bit of flex in the iron pipe, the front end of the log almost always shifts a bit toward the blade. Typically about 3/8″ for a 6 foot log. The longer the log, the more it will shift. I try to take that into account when I align the front and actually plan it so that when I tighten the clamp it shifts out to where I want it. It sometimes takes a few attempts(nothing major).
The sawmill sled is ready for the first cut on the log.
From here, I turn on the bandsaw and start pushing the sled through. The sled is almost an inch high, so it reduces the amount of resaw capacity on your bandsaw by just under an inch. My bandsaw has a 8-1/2″ resaw capacity, so the biggest log I can mill is about 7″ in diameter.
Here the cut is quartering, half a log.
When the first cut is done, I unclamp the log, move the sled and log back to the starting position, then put the newly cut edge face down on the sled. I again use the pencil mark indicating the center of the log to align the log with the reference lines. I then push the sled through again. Now I have two faces at right angles to each other. At this point I can use the sled to cut off a slab of whatever thickness I want.
Safety Concerns
Safety glasses and hearing protection are a must
When pushing the sled from the back, I always push by putting my hand onto the tail-piece of the clamp. The clamp can’t contact the blade, so neither can my hand.
Since logs are round, you have to be careful not only of the blade entering the log at the top (usual concerns for a bandsaw), but you also have to watch out for the blade exiting the log because the log is not flush to the table.
I keep a couple of shims and a mallet handy and drive a shim into the end of the log once I am a foot or so in. This helps prevent the blade from binding in the kerf and stalling the saw.
Density of logs can vary within the log. It can be dense and slow cutting in one section then go into easy cutting punky stuff without warning, so don’t push too hard on the sled AND keep aware of where your hands would go if the log slipped. Keep them out of the path of the blade.
For my uses (not fine furniture) this sled makes it pretty easy to turn small logs into lumber, and that makes me happy.
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