Thread: Need Help to identify a special notching circular saw and / or blade.

Dado blades.
Use them for checking out top and bottom plates when building walls. Something that is rarely done now.
Lots of other uses.
Have a look on ebay. Google is your friend.

Hooroo.

Hi Chela.
I have never seen a 2 inch wide blade for a circular saw or a saw that could take such a blade.

It may be that what you saw was a method of using a circular saw to cut the notch .... it is the way that the saw is used not the blade ... repeated cuts across the timber that leaves thin remnants that are then broken out with a hammer

Regards

Rob

https://www.timbertools.com/Notchers/
http://mydougu.blogspot.com.au/2010/...er-cutter.html

I believe they're way more common in the UK, where notching top & bottom rails is still common. (I've only ever used one once and, frankly, it terrified me for several reasons. Which says a lot, given some of the frankensteined contraptions I've used out of necessity. )

They are hand-held circs specifically designed to take dado blades.

For God's sake, don't try fitting a dado blade to a standard Aussie CS! It would not end well for the saw or the operator.

As said above they are virtually unheard of in Aust. very big in the US

If you are looking at doing a lot of framing with trenched top and bottom plates then the way we used to do them was with a Radial Arm Saw and a dado blade. Pretty quick with sharp blades and once set up. If you want the more portable option then Makita make the 3800N and the 3803A Groove Cutter. Basically a circular saw with a long arbor to take a 2" Dado blade. The blades are 120mm in diameter by 46mm with a max cutting depth of 30mm.
I've seen a few come up for sale on ebay and gumtree over the last few years and they sell for $400-$600 secondhand. Brand new I think they go for more than $800 + and I'm unsure whether you can actually get them in Australia.
I'm unsure why you would want to use them for notching roofing frames ??

Stewie

Thank you all for your help and advice

Very Much appreciate it.

Originally Posted by Wimmera Jack

Dado blades.
Use them for checking out top and bottom plates when building walls. Something that is rarely done now.
Lots of other uses.
Have a look on ebay. Google is your friend.

another approach is to look at the relative cost of labour and materials

In days gone by, labour was relatively cheap compared to materials and nailing laborious.
These days, pine framing is relatively inexpensive and power nailing as cheap as. The easiest & fastest way to create a "notch" in the top or bottom plate is to nail on a spacer between each stud.

Trenched and untrenched plates



Plates are sometimes trenched where the studs are located. This was a very common practice in the days when wall frames always used rough sawn material, because off-the-saw timber tends to vary in size along the length of the piece. It was also used when wall frames were made with green timber, to help stop the studs from twisting over time as they dried out.

But with planer-gauged, kiln-dried material, trenching is no longer necessary for these reasons. Nonetheless, it is still sometimes requested by builders, and it is also used by some manufacturers to help set out the positioning of studs. Timber Plus Toolbox, Assembling wall frames, Wall frame components, Trenched and untreched plates