Troubleshooting Curved Miter Cuts

Big chopsaw cutting a little concave? Blade quality and technique might both play a role. August 8, 2008

Question
I have a 12" Dewalt miter saw with a 12", 80 tooth, Dewalt blade. When cutting 45 degree angles I sometimes get a tight fit on both ends but the middle is loose. The cut is not straight- it is concave. Could this be the blade? What is a good blade to use?

Forum Responses
(WOODnetWORK Forum)
From contributor A:
I have a 12" Bosch with a Freud blade. I sometimes have the same problem. I have come to the conclusion that the saw has the power to "hammer down" through anything, but when you do it causes the blade to deflect. Try easing into your cuts a little slower. As for your blade question, blades are a "get what you pay for" kind of thing. I use the Freuds because they work pretty well and I can afford them. There are probably better blades out there, but I'm stubborn enough not to take out a mortgage to get a better miter saw blade.



From the original questioner:
What Freud blade do you use? I saw one that is described as a cabinet makers blade and I think it is not a thin kerf. Would a heavier blade make a difference?


From contributor B:
Get the Forrest Chopmaster Blade, as many teeth as you can afford. It's probably $50 more than what you get now. It has a thick blank that resists moving under load. Also slow your cut down and let the saw do the work.


From contributor A:
The blade I have on my 12" Bosch is a Freud Diablo and it is a thin kerf. The blade I have on my old 10" Delta is a Freud industrial that is a full kerf. It is a much better blade, but the equivalent blade in a 12" was very pricey and I was feeling poor at the time. The Bosch saw came with a 40 tooth construction blade that is fine for chopping off 2 x 8s, but worthless on trim.


From contributor C:
My experience echoes what contributor C said - get yourself a professional blade, the thicker the better and you will have better results. I changed out Dewalt's super thin blades for the Forrest Chopmaster and they are worth every penny in my opinion. There are other companies that make good blades too, but the prices are similar.


From contributor D:
The Dewalt blades are barely worth what you paid for them. Not stiff, not sharp, not properly trued. Like others have mentioned spend the money and get a Forrest or another high end blade. The more expensive blade pays for the difference in cost in the first sharpening. Also with the Dewalt saws take a few seconds to come up to full blade speed.


From contributor E:
A very good blade to use is a 12"x 80t with a -5 degree hook with an atb grind. You will be very happy with this type of blade and most high end blades will have c-4 micrograin carbide for longer life, and you don't have to pay much more.


From the original questioner:
Other than the Forrest blade what are some other good brands? Where can Forrest blades be purchased?


From contributor C:
For the 12" blades you'll most likely have to get them from Forrest. I don't think many of the local woodworking stores will have them. You can also try the Freud blades, but stay away from thin kerf blades.


From contributor F:
I have a Dewalt miter saw and I have the same problem. I tried different blades but nothing helped. I think the problem is in the arbor, with not tight enough tolerances. I even took it to Dewalt service and they tied replacing the bearings and arbor but it did not help. I bought a Hitachi 10" and it cuts perfectly but I don't know if the 12" would do as well. I would see if you could try your blades on another brand of miter saw first to see if they work alright there.


From the original questioner:
I ordered a Forrest Chopmaster blade and should get it Tuesday. I hope it makes a difference.


From contributor G:
You should be quite impressed with the Forrest, but listen to what others have said in letting the saw do the work, and keep the blade sharp. You shouldn't use it until it's burning its way through the cut. The Dewalt is an excellent saw, my personal choice, as are the Forrest blades. Other names would be Amana, DML, and Tenru, but stick to the heavier bodies. Thin kerf blades are not for mitering, as they will all deflect, causing the conditions you reported in your original post.


From the original questioner:
I got my Forrest Chopmaster blade today and tried it out right away. What a difference the blade makes. It cut through a maple 2 x 4 like it was butter and miters in oak could not be better. Thanks for all the advice.


From contributor B:
Glad to hear it. I got my first Chopmaster when I picked up my 12" Hitachi slider. It's really a nice blade.