I have had some interested customers ask why the 1:4 ratio was used for the original Saddle-Tail dovetail marker. I have to note that while one side of the Saddle-Tail is for dovetails the other side is a convenient saddle square so there is no ratio at all on the second side! This is an important feature of the Saddle-Tail as its two tools in one and allows you to use one tool for both operations when making your dovetail joints.
I am a tails first woodworker so I use the slope side of the Saddle-Tail first to layout my tails. After saw the tails and chop out the waste, I use the completed tail board to mark my pins on the end of the board. I use a marking knife for this operation to ensure that the joints align tightly with no gaps. I then use the square side of the Saddle-Tail to drop the angled marks on the end of the board to extend the vertical exposed portion of the pin down the face of the board to the baseline. I plan to be working with a good friend and online woodworker to make a short video in the next Month or so to show this process. Stay tuned to this blog for its publishing.
I really like the slope of 1:4 or 14 degrees (it’s incredibly close as you will see here shortly) for my dovetails. Other producers of dovetail markers use ratios for a subset of their markers and degrees for others. A popular woodworking tool and catalog company for instance uses slopes of 1:6, 1:8 and then uses 14 degrees for their third dovetail marker offering. I decided that I would use ratios for all my dovetail marker slopes. I could have picked all angles but I chose ratios and stuck with it.
To help woodworkers out there that would like to know the equivalent angles that are represented by the ratios and what the ratios of popular round numbers, here is a helpful table:
You can see that these ratios are incredibly close to popular angles in degrees. It would be extremely difficult to be able to pick these differences up in your dovetails on a piece of furniture by eye.
So in closing your 1:4 Saddle-Tail is for all practical purposes 14 degrees, the 1:6 is close to 10 degrees and the 1:8 is about 7 degrees. It’s best not to worry too much about these small differences from ratios and angles and best to concentrate on getting your most accurate results with your dovetail projects with accurate layout, precision sawing and chiseling. By concentrating on these aspects you will get your show your best results! Please send me your photos of items you have built using your Saddle-Tail!