The Kerfed Lining

I cut the kerfing on the lining this weekend.  It is used to hold the sound board and back board to the rim.  The lining is cut or "kerfed" so that it easily can be bent around the rim.  I made a  3/8" x 3/8" strip of walnut on the table saw and then used the band saw at a 45 degree angle to cut the strip in half diagonally.  This will give me the two strips of lining I need for the mandolin.  I then used the jig I made to cut the kefing into the strips of lining.

The jig is simply a board attached to a guild the fits into the table saw miter gauge slot.  The board on top is a backing board for the lining to rest against while cutting the kerf slots.  I am ready to glue the lining in once I an dome gluing up the rim.
  

Kerfing Jig

Bending The Rim (Done)

I ruined about 10 strips of maple before I succeeded in bending my first mandolin rim.  I took the thickness down to from 1/8^th of an inch (.12) to .09.  This time I made sure there were no saw marks at all on the strips of wood before I attempted to bend.  On some of the last attempts, they were not sanded well enough and that’s where the cracks happened the most.  A 1/8^th of an inch was way too thick on my last attempts.  I had much better success this last go around.  Using a bending strip is also key to keeping the bend uniform.  I think I am now ready to try some fancy wood.  There is one alteration I would make on the bending iron.  The smaller tube for tighter corners is not getting hot enough.  I will have to make a separate bending iron next time.  I also have my first loss of skin....  First Blood part one.  I sanded right through my glove on the belt sander.  I still have one good middle finger if needed for an outburst :)

Side Bending (with Video)

I cut four 1/8^” X 1 7/16” x 30” strips of maple and spent the evening testing my bending iron……and I broke every single piece!  I used a spray bottle to wet the front and back of the first strip.  My first bend did pretty good but it cracked in a couple of spots.  I tried less water on the next attempt and they snapped right away.  I also experimented only wetting one side with no luck.  There were a few flat spots as well and will have to try bending straps next time. 

As my strips dwindled, I tried wetting a rag and draped it over the hot iron and tried bending the maple on top of the rag.  I think with bending straps and the hot rag technique, I may have better luck the next go around.  I now have a pile of useless bent maple.  It looks like remnants of an angry John McEnroe temper tantrum. 

I will also try thinner strips and bring down to just under 1/8".  I may try soaking the strips first for 5 of 10 minutes and see if that helps.  

My 2nd go around was a but more successful,  but I still ended up with another pile of kindling.  I am getting closer and feel a bit more optimistic than my last attempt.

Hand planing the soundboard

The pegs for my workbench worked well for holding the top down while I planed the top.  I used two different hand planes and my small Ibex plane for this job.  I did not realize how small the Ibex plane is.  I am afraid I might lose it….or swallow it.  I have seen pictures of others with tape on their fingers.  I now know why.  I did use gloves but swear I almost rubbed the fingerprints right off.  I will be buying some white wrapping tape like they use in the hospital.  I have the rough shape on the top done and am now ready for graduating.  I still need to build my dial indicator before I can move on.  I was so excited to start that I forgot.  So far so good on the soundboard.  I will wait a couple of days for my fingers to heal.  

Cutting the soundboard and routing

After countless hours of late night studying I finally reached the tipping point and decided it was time to officially start on my mandolin.  It is quite a daunting task to start the process of carving.  There is only so much you can read, and at some point must cut into your project.  The worst case scenario I ruin a piece of wood and have to start over.  I wonder how many sound boards Stradivarius ruined before he mastered them??

I sanded the back of the soundboard flat and planed it to 5/8 which is the starting thickness.  I also planed a scrap piece of pine to the same thickness to use as a test board for my next step.

The finished edge of the mandolin will be .875 where it attaches to the rim.  I set my router table up with a 3/8ths rabbit bit and made multiple cuts on my scrap piece of pine setting the cutter up to leave a .200” lip.  This will allow about the thickness of a business card for finish sanding.  The mandolin soundboard will have to be routed upside down with the top on the router table since the router is set up underneath the table and not overhead.  The soundboard billet was slightly beveled when I bought it, but when I planed to 5/8ths, it left a flat surface.  This should be enough of a flat surface for my router table.  I am pretty confident I can keep it from rocking.

The routing turned out great and I now have a .200 most of the way around the soundboard.  It starts where the scroll ends and stops at the upper point. This will give me a ledge to hand plane down to from the center to the soundboard to the outer rim.  I will use my graduation templates and start the process of graduating the top.  I look forward to using hand tools for a change.  There is less of a chance to screw up.  Not that I ever have…..gulp! 

Fixtures finally done

Well finally I have all five of the main fixtures and templates finished.  This is why it took me so long to pull the trigger on actually building a mandolin.  I have be contemplating this build for years and was always stopped by the thought of the daunting task of building the jigs, let alone the mandolin itself.  Including the bending, the fretwork, binding, inlay and finishing, that can stop most folks from even trying.  If you also factor in the tools involved to do one from scratch, these are the reasons it took me four years to actually buy the book. 

It reminds me of when I built my house.  It took 1 ½ years to finish.  At times it seemed so overwhelming.  I use to call it the largest honey-do list.  As I started the building process, I would focus on one task or one day at a time.  As the weeks grew into months, my confidence grew as well as my skills.  When I took a short rest to look backwards at my progress, the overwhelming feelings dissipated.  I am counting on this same feeling for this protect.  This is the great milestone for me on this new journey that I almost did not start.  Let the carving, bending and no mistakes begin!!

Neck gluing Fixture

This next fixture is for holding the mandolin at the proper angle when you glue the neck on.  The curved piece of maple is set at the same height and location where the bridge will go.  The holes allow for clamping the neck down.

Truss Rod Fixture

Jan 5th, 2016

To properly cut the notch down the center of the neck for the truss rod I built a jig to hold the neck at the correct angle.  I used a 1/2" piece of plywood for the base and cut the neck support and safety blocks on the band-saw.  Once attached I cut out center out to allow the fret-board to lay flat while raising the peg-head which will allow to cut a slopped slot for the truss rod.

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.