miter on the tablesaw with a Rebbet Scale?

[AviOren]

Mitering Picture Frames on the tablesaw. I am wondering if anyone came up with a method to miter a picture or a painting frame on the tablesaw without calculations for the side’s length?

As I understand it, most professional picture framers prefer using miter saws (chop saws) equipped with REBBET SCALES for doing it. See one such arrangement here:

http://www.framingsupplies.com/Clearmount/Clearmount_Miter_Saw_System.htm

Notice that the 2nd 45 degrees miter on the frame side is done by clamping the workpiece after the first miter is cut, on top of the REBBET SCALE and going by the marked numbers which determine the length between the ends of the rebbet in the molding. There is no need for calculations.

See here Jolkovski, Robert M. (34 Hamilton Rd., Arlington, MA, US) patent on Miter saw measuring fence, United States Patent 6899006

http://www.freepatentsonline.com/6899006.html

Click on the sketch to enlarge it.

Jolkovsky’s company sells picture framing equipment.
See the Producer Miter Saw on which Bob holds the patent:

http://www.pictureframeproducts.com/products.htm


Bob, is quite a fellow! He wants to sell you his patented digital measuring gadget together with the expensive Rebbet Scale.



However, many amateur woodworkers would prefer using their tablesaws for it.


See here one method for using a REBBET SCALE on a tablesaw:



http://books.google.com/books?id=-AAAAAAAMBAJ&pg=PA98&lpg=PA98&dq=45+degrees+grid+ruler+for+mitering+picture+frames&source=bl&ots=qEPDFsBMu1&sig=stuzp7uuwi68Lbm3fSqEIJpmU&hl=en&ei=mZ7wS6vvIIPtlQfygrmOCQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBIQ6AEwAA#v=onepage&q&f=true


If the link does not work for you then Google- search for the article in Popular Science magazine of Dec 1970 by Frank L Greenwald, titled : “Build a better Miter Jig then you can buy”. On pg 98.


In Greenwald’s method I don’t like the fact that the workpiece is not supported on the back of the cut which could lead to tear outs.


Any idea?

 

[MIKE NOAH]

I'll be honest with you, I can figure the math much easier than I can figure out how those jigs work. For me the critical dimension is the required rabbet length to accomodate the glass or picture. Subtract 2 X the rabbet's width from the required length is the inside measurement and add 2 X the stock's width to that ( the inside length) is the outside measurement. That and a miter sled with stops or a miter gauge w/ stops is all I have ever done...that being said I don't build very many picture frames.
Mike

 

[AviOren]

​

Molding #107​

Glued two components:​

#1- available at xylo as item # OG-3 1/4 but only in poplar, needs some reworking
#2- available at xylo as item # 35-1 1/2, in several wood species and also in poplar, needs some reworking
#3- canvas 11/16" to 3/4" thick
#4- ribbed turn button 5/16" wide x 1" long and a #6 x 5/8" long flat head wood screw, to hold canvas in place​

Finish if all is poplar: water based aniline dye, several coats of Bartley's gel stain, and Bartley's clear stain varnish.​

xylo = http://www.savannahmillwork.net/xylo-site/​

p.s. it seems to me that xylo went out of business about a year ago. So I been making my own moldings, mostly from cherry wood, something like this:​

https://7012066802238894096-a-18027...e/canvas-painting-frames/Frame moldings3.png?​

and​

Molding #101​

Made of three or four glued components​

#1- Use Lonnie Bird's 7" Crown Molding Set, by CMT part # 235.006.07 to saw the cove on the 7/8" thick stock. Do it on the table saw with fences set at 45 degrees. But I have found that coving on the router table with a bit like this does a smoother job:​

http://www.mlcswoodworking.com/shopsite_sc/store/html/smarthtml/pages/bit_molding2.html​

The one for crown molding

#2- Canvas 11/16" to 3/4" thick.​

#3- Ribbed turn button 5/16" wide x 1" long, and a #6 x 5/8" long flat head wood screw, to hold canvas in place .​

Wood: Seen parts-Birds eyes maple, etc.​

Finish: water based anyline dye, Bartley's gel stain, and Bartley's clear gel varnish​

 

[AviOren]

Hi Noah, above I posted a cross section of one type of molding that I been using. Notice that the frame molding is sort of crown molding projected forward. I am not sure that your calculation apply in this case. It's in three dimensions. See here a similar frame:


Photo #1

http://picasaweb.google.com/PaEden/PictureFrames?authkey=Gv1sRgCKyMjfO36d3I_AE#5386232982214801954


p.s. first time that I see the name Noah as a family name and not a first name which I know dozens of persons as such. One of my family members is named Noa (a lady). Many ask why there is no "H" in the name. IMO, a male named Noah should be spelled Noach.

 

[MIKE NOAH]

Sorry about that Avi, I was paying more attention to the Greenwald example which was for a table saw. When I saw both cuts being done on the same side of the blade and only a 1" high flat fence I assumed the blade was staying at 90 deg. to the table and we were only talking about flat stock. The only time I have cut crown molding on a table saw I bolted an angled piece of scrap to the face of the miter gauge to represent the spring angle and used basically trial and error to get the lengths right :BangHead: . Looking at your example with the built up of pieces my math won't work.
Mike

 

[AviOren]

Mike, to miter the frame sides I used a similar sled as this but with longer fences (40"):

http://plansnow.com/dn3083c.html

I also used a core, like shown in the photo that had the same cross section as the rebbet made in the molding. This core ends were pre mitered to exact length of the canvas painting. In my case the core was clamped against the miter slider fence while the core's mitered end was kissing the table saw blade. I attached the core to the miter slider fence with flat head screws (could be double sided adhesive tape). Now I backed the miter sled and clamped the molding over the core and the fence while its one end fitted the end of the core, and the uncut end of the molding was protruding forward. At that point I used the miter slider to cut the molding to exact length.

Now, I am looking for a method to do it without making a core.:roll: