cutting depth for BT3K

[ballard770]

What is the expected cutting depth capability for ripping 2X4 or 4X4 lumber wet and/or dry. 2" (1 1/2" nominal) goes well but sometimes it seems to cut well thru a 4X4 and other times it seems slow. With a sharp rip blade of course. If slow is it an indication of needing brushes? Results have sometimes varied between my two saws with the same blade.

[leehljp]

I am not at my saw at the moment and my memory has gone; however I think the BT3000/3100 can rip and cross cut at 3 1/2 inches. One needs to be skilled at ripping at that depth but there was a fellow from Australia years ago that made some beautiful and expensive table and chairs with the BT3000. He did a lot of ripping of 6 inch boards through the 6 inch side, if I remember correctly. The furniture sold in the thousands of dollars. The point being is that the BT IS capable with the right touch.

[cwsmith]

"The point being is that the BT IS capable with the right touch."

And, if I may add... that is generally a "light touch". While I have no where near the talents and craftsmanship skills of many that I've seen here on this forum, the one thing I have learned from my BT3100 is that it is a saw with tremendous capabilities. BUT, if needs to be handle with finesse. Unlike the big HP table saws, on which mighty motors might handle robust feeds, the BT requires a bit of patience and understanding. It's motor is lighter in HP; but, IMO, higher in cutting ability with it's faster RPM. I think at one time I read that the BT had a better depth of cut than other saws on the market at the time. Just let the blade do it's job and you'll be surprised at the quality of cut it delivers.

CWS

[Black walnut]

What is the expected cutting depth capability for ripping 2X4 or 4X4 lumber wet and/or dry. 2" (1 1/2" nominal) goes well but sometimes it seems to cut well thru a 4X4 and other times it seems slow. With a sharp rip blade of course. If slow is it an indication of needing brushes? Results have sometimes varied between my two saws with the same blade.

Wet construction grade lumber or any wet lumber for that matter is going to be harder to cut.
As already mentioned the saw is capable of full depth cuts through nominal 4x4 lumber. Ripping is best done in several passes.
The motor struggling is not a sign of brush problems in this case.

[LCHIEN]

There's a number of parameters that come together for thick wood and cutting speeds.
With the BT3 you are unfortunately fixed and limited int he HP your motor has.

When cutting challenging woods - thick hard, dense you have to have enough power, The sign of not enough power is that the saw blade sloes and stalls when you use too much feed speed. The motor will audibly slow down and threaten to stall. You do not want to slow the motor significantly nor do you want it to stall.. Running at protracted high load (slow speed) will cause excessive current to flow and it will cause motor failure if the heat gets too high and melts the wire enamel insulation. You cannot run the BT motor for more than a few quick seconds slowing down. If you allow the motor to stall, that can also burn it out and also you risk breaking the belts at $ 40 for the pair.

Your only alternative to allowing the motor to slow too much is to reduce the feed pressure and speed. That in turn can lead to burning of the wood and blade as the sides become burnished from continued friction since the wood is not moving on. Bad for the cut and bad for the blade.

Another problem is taking out a lot of wood from a deep cut can fill the gullet - the space between teeth. If this gets full it compresses the sawdust in the gullet to the point where it lifts the tooth off the wood and just spins burnishing the wood. This happens with deep rip cuts - the wood is more easily removed with the grain. The solution to this is to use a ripping blade - one with 24 teeth (less than normal) and deep wide gullets. THis gullet will carry the wood around to the bottom of the saw where it can fall out before becoming overly full.


The best solution is to get a high powered saw for which most of us is not an option.
Use the correct blade - particularly a ripping blade when making long deep rips. You can reduce the load by making a cut in stages, 2 inches deep first pass, then a full 3.5" deep the second pass. Takes twice as long but reduces the saw working load in half on each pass. As long as you have everything set up and locked the cut should be good and not visible or at least easily cleaned up. If a real clean edge is important, take your first two passes with the cut 1/16th or less overside and then do a shave pass with the blade set for full cut shaving the extra 1/16th off.

Other things to improve your saws power for long deep cuts:

• make sure the blade is clean - no resins on the edge to burn easing your slow speed end before burning
• Make sure the saw is fed with the best power possible - no extension cord, plugged directly to the wall with a 20A circuit if possible If you must use an extension cord, make it 12 Gauge or better! and short as possible. This will reduce voltage loss in the wires and reduce the additional current required to get the same power.
• Avoid significant motor slow down and stalling.
• Thin kerf blade (.093 or 3/32") will reduce power quite a bit over full Kerf (1/8")

[JimD]

I agree with LCHIEN except for the thin versus full kerf blade. I don't think thin kerf blades makes as much difference as most suggest. I use both and see little difference.

I recently built a bed out of construction grade 2x12s of southern yellow pine. I did the long rips with my DeWalt track saw using the stock 48 tooth blade. I also crosscut a few times. I had trouble only when the wood pinched the blade. The DeWalt has a riving knife but it did not completely overcome the warp of the wood. I used my Milwaukee to finish off one cut and it too struggled. So I started having a wedge handy and that solved it. The DeWalt only has a 12A motor. My son gave me a ripping blade for my track saw for Christmas and I will use that in the future.

The fact that you only sometimes have an issue with the BT3100 suggests warping may be an issue for you too. Getting the right blade is always a good idea but you might also want to have a wedge handy to drive into the kerf if the wood is pinching the blade.

[LCHIEN]

Uh, to the original question, the ripping capacity is 3-1/2 inches which is a bit more than most saws. THis is probably due to the small dimensions of the motor and the mechanisms allowing the blade to sit just a bit higher int he saw than most tablesaws.
I think must table saws are 3.25 to 3-3/8 inches.