Siminoff Joint Fixture

Jan 5th, 2016

I decided to use the Siminoff Joint for this mandolin build which requires a jig to cut the V joint at the proper angle into the head block..  His book does not explain very well on how to build one so I decided to buy the Pro plans from him.  Again, a bit frustrating that these were not included in the book.  Just charge more for the book.  I am sure I would eventually figure the jig out but I don’t have much time and would like to build a mandolin, not figure out a jig from a black and white picture from only one angle.  

The Pro plans for this jig were a bit confusing for someone who has not built a mandolin before.  I emailed Roger Siminoff and he sent some actual pictures of the underside of the jig.  There must be more than one way to build the jig since his pictures contradicted what the Pro plan said to do.  After building it, I think maybe it does not matter where you put the hinge, but if you have never built one it is quite frustrating since you only get once chance to do it right come time to cut the slot.  It does say to practice on scrap which is what I will do for sure.  One more issue I noticed, some of the dimensions are written down and some you have to measure off the plans.  It would be nice to have more detailed written down measurements.  

Part of my confusion on this particular jig is whether to put the hinge on the side of the angled block or on the top.  I have two separate pics with two different ways.  It would be nice to get some clarification for first timers who are nervous they may blow this and ruin the mandolin.  I can tell the book is written from a seasoned builder who forgot what it is like to start from a stand point of a total beginner.  With that said, I guess that’s why maybe most people don’t start out with an F style on their first build.  Then again, the book does say how to build a mandolin.  

As usual I glued the paper template from the plans and cut them out on the band saw.  This was probably the hardest jig to build out of all five that I have done.  Maybe next time I will try the dovetail joint.  It would be fun to compare the difficulty level.  For now I will make sure and test this on plenty of scrap wood.