new to dado blades and need help

[russell johansen]

Very new to woodworking and no one local that can help. I just bought a set of Freud dado blades for about $100. Now I have it home and I am not totally sure how to set it up. Can someone point me to a website or discussion on setting up the dados, hopefully with pictures. Specifically, I have the following questions: (BTW, this is NOT a wobble set)

1: can someone help me with the vocabulary: I see three distinct types of blades. what are these called- one looks more like a saw blade while two are black and two are small (shims?).

2: Once I know the names, can someone tell me the order these go in? Are there general rules of thumb to follow?

3: I have a large washer that goes on the normal saw blade. Do I use this with a dado?

4: Any special safety tips or maintanence tips? I know about hold downs and push blocks.

Thanks in advance for the advice and help.

[Mark Rios]

What model number is it?

Welcome to the creek, BTW.

Edit....Try this webpage at Freud.com http://www.freudtools.com/woodworker...tmr_srvc.shtml

See if they can help.

[Hoa Dinh]

Maybe this can help you.

[Andy Fox]

Russell,

It sounds like you have the SD506 or SD508 set? I have the 506, so I'll try to help. My blade package has a piece of paper with a chart showing chipper and shim combinations listed to setup for specifc widths. Although, it is somewhat of a cryptic.

The 2 "saw blades" are the cutters or outer blades. These must both always be used, and they always sandwich the shims and chippers. They can also be used as a pair without shims or chippers to make a 1/4" width dado. Install so that the carbide teeth of one blade are in the gullett (toothless space between teeth) of the other.

The long pieces with teeth at each end are chippers. There are 4 1/8" chippers, and 1 thinner 3/32" chipper. These are installed between the outer blades in different combinations to achieve the correct dado width. Install the first chipper so that the carbide teeth of the chipper are in the gullett of the adjacent blade. Rotate each successive chipper 90 degrees as it is installed, and make sure the final outer blade is installed so that the chipper teeth are in a gullett.

The small, round, toothless circular pieces of metal or plastic are shims to fine-tune the width. These can be placed anywhere between the two outer blades, but spread them out when using the thicker ones.

The arbor washer can be used if it will fit, but with wider dadoes there often isn't space to torque the nut properly with the washer installed. In this case, it's better to just not use the washer.

Don't cut more than about 1/4" depth at a time. Always use a miter gauge or sled for dadoes, and a rip fence for grooves. Make plenty of test cuts to fine tune width and depth. Verify that the dado or groove will be square or parallel to the edge of the workpiece. (If the edge against the mitre gauge or fence isn't square to the rest of the piece, you could end up with some funny looking shelves.... I tried that once. )

Make sure all blades and chippers are installed with the teeth facing the correct direction, and that none of them touch each other. Don't even turn the saw on unless you're sure the the setup is correct. Don't use any blades or chippers with cracked or chipped teeth. Flying bits of broken carbide kill with the efficiency of a hand grenade.

[Charles McCracken]

Andy has given an excellent response. I would add that I think the dado in question is the SD206 or SD208 and would, therefore, have (4) 1/8" chippers and (1) 1/16" chipper. The chipper thickness is measured in the body, not the tip. As Andy said, the two outside saws must always be used together and will make a 1/4" dado, Install a 1/8" chipper between the outside saws and you will make a 3/8" dado. Add a 1/16" chipper and you will make a 7/16" chipper and so on. Some saws have a slight undercut on the arbor right where the threads start so if you will be using the 1/16" chipper it is wise to install it right beside the first outside blade.

Charles M
Freud America, Inc.