Sunday, October 20, 2013

Soft Case Gig Bag for the Clawhammer Banjo (full size)

Years ago I made a guitar case cover to protect a guitar from heat and sunlight during a long summer road trip through Wyoming, Colorado, Kansas, Oklahoma, and Texas where the guitar was going to be riding in the back seat.   A musician friend introduced me to a product called "Reflectix" which she uses inside her van windows and roof for insulation and cooling when camping.   It is basically some bubble wrap with mylar surfaces to reflect heat and light.  It comes in various sized rolls at your local hardware center and is quite inexpensive.   I put the newly covered case out in the direct sun and left it for hours.  It did not even warm up inside.

Not that I need much in the way of sun protection with the banjo, it will benefit from some cushioning and insulation,  as well as the banjo gig bag/case being quite light.

The plan initially is to cut out 4 oversized banjo shaped pieces, two to be used per side with some cardboard reinforcement inbetween, all spray glued together.  Side strips will be cut out and both the side strips and the front and back pieces will have denim from some sacificial jeans from St. VDP glued to them on the outside surface, and some flannel from old shirts glued to the inside. 

After the glue is dry I will sew all the edges together using my White's Family Rotary treadle machine, covering the raw edges with cloth adhesive tape which will then get another row of stitching.  A zipper will be centered along the bottom end for a bottom loading case.  Straps and handle will be attached at the end.

For now, here are some pix showing where I got to tonight.

More during tomorrow's session.

21 Oct update

Took the table and stuff outside and sprayed and glued.  The front and back pieces are laminated from two pieces of Reflectix with a banjo head sized piece of cardboard between them.  The denim front and back were then glued on.

I inserted some zipper flys in the ends of the side piece denim to form the end load zipper opening.

Then back to the thrift store for some sacrificial flannel shirts for the inner linings.  Below they have been glued to the other side of the pieces.

Tomorrow I will decide how I am going to assemble it.  So far I have broken 3 leather needles in my treadle machine attempting to sew too thick a spot....

I trimmed the inner reflectix on the top and bottom to 1/2 inch larger than the banjo to make the suturable parts thinner.  Still not going to be able to machine sew it.


Oct 24 - Stapled a side into place and hand stitched with fairly large stitches, and pleased with the overall look.

Outer edges will get trimmed and covered with "athletic adhesive tape" then sewed again either with a running stitch or a spiral whip stitch...

OR....   perhaps there is a cobbler/shoe repairman locally that would be willing to run the taped edge through his sewing machine he uses for sole edges.  I will look into that.

Both sides are on, top is ready to attach..

As soon as my finger stops bleeding...  apparently tried to snip a chunk off the tip...

Not the best thing I could have done a week away from a music camp...

Oct 27 update...

Finger healing well, should be good to go for the camp next weekend.

As the cobbler/shoe repairman wanted $50.00 to sew the edges, (twice what I have in for materials), and that my treadle machine would not feed this thick a "fabric" sandwich I resorted to manual assembly, a task which proved fairly strenuous...

Gig bag top attached with big basting stitches to put shape to it and test fit the banjo.  The edges will be trimmed to about 1/2 inch from stitch line then covered with white tape and sewed again.

I am pleased with the rigidity of the case once all the edges are joined.  

I still need to make a foam/denim/flannel flap for the opening, construct a handle and shoulder straps for backpack carry.

Coming along nicely...

Oct 31 update - - - - - - - - - - -

The flap has a piece of spring steel in the bottom edge to keep it in place behind the zippers when closed.

Instead of white cloth tape for the edges I opted to use black gaffer tape and I think it worked out well. I whip stitched around all edges with denim orange thread, breaking no less that 6 needles in the process.  Each stitch was made by pushing the needle through with a pair of spring open pliers.  Going through tape both gunks up the needle, and dulls it to the point of it breaking once in a while.

Once stitched, back to SVDP for some handle strapping, which matched the case surprisingly well.
I also got a backpack for sacrificial straps for the future.

As for now though, I deem this project not only complete, but functional and fitting with the theme of the instrument safely cushioned within.

Til next time...   stay tuned


Wednesday, October 9, 2013

1/12 Scale Clawhammer Banjo (This project is on indefinite hold)

Last month I went to Uke Fest at Ft. Warden in Port Townsend, WA.  During a visit to the local musical instrument emporium I was drawn to a tack head clawhammer banjo for sale.  It turned out to be a Civil War era recreation fretless banjo with a huge 13 Inch diameter calf skin head, oak rim and maple neck.  It is one by banjo builder Eric Prust who specializes in this particular era of banjo.

As it has pseudo gut strings, a through dowel rod that the tailpiece ties onto and friction tuning pegs it might be a candidate for fairly easy shrinkage.

Here is the original on the day I brought it back to Ft. Worden.

The build commences with a thin strip of oak on which I sanded tapers on the end faces, steamed and then bent around a 1inch steel punch handle.  When cooled I slathered Elmer's glue all over it and rewrapped it, clamping it in place with a dozen miniature plastic clothespins. 

When this was dry I was able to mount it to a mandrel on my drill press and sand the outside smooth, and then sanded the inside with paper on the mandrel.  A quick touch of the edges to the belt sander to even up the wrappings produced a plausable and rigid banjo rim.  Final measurements will be approached later.

It is out of scale in thickness, but the unbent strip in the picture above should make one closer to scale.  I will take pix of all the steps with the next rim.   Banjo rims vary in thickness in the real world so it would not be totally out of place if i used the first one.

10 Oct  update - 

I cut a square strip of maple scale 2.5 inches sq, laid out and sawed, filed, whittled, and sanded a neck.  I also cut a scale 3/4 inch sq dowel rod, and rounded off the part that will inserts into the hole in the neck heel.  I still have to drill and file a hole in the dowel stick for the wedge holding the neck to the rim.

That will complete the major big work leaving things like final fittings, ebony pegs to be turned, carved and drilled, and some star branding irons to be made to brand the markings onto the outside of the rim and the peg head and scoop.  I also need to cut out a bridge and tailpiece.

Material for the top is still being debated.  I am not sure what skin would be thin enough to mount and shrink...   mouse maybe?  Think I will call some local taxidermists to see what they would recommend/have available.  I will also have to index drill some 40 tack mounting holes 0.083 inches apart and glue in teensy round head tacks.

It sounds worse than it is, but putting my process into writing helps me concentrate on the project, and you get to see how my mini mind works.

Oct 12 update -

I went back and remeasured and recalculated the shrinkage for the hoop as the first one looks considerably too thick and slightly small.   

I sawed a new oak strip just under 0.02 in thick and steamed and bent it around the same mandrel with enough wraps of blue tape to equal 12 1/2 inches which is the ID of the full size banjo.

Tape around a forstner bit with double sticky tape for outer sanding on the drill press.

A piece of plastic vacuum hose fitting serves as a mount to file the holes square without puncturing fingers on the non file hand...   (lessons learned the hard way are the best retained)

Much closer to true scale now.  The first pot will probably find it's way into a tenor or a bluegrass banjo at some point in the future.

I suppose that I should have used an ink stamp or stencil to do the stars.  The original has them branded in.  I made a little branding iron and went for it.  a couple came out nicely...

And a couple were slightly overdone.  Temperature control at that size gives a very narrow window for getting a clean stamping/branding.

As this is more or less a proof of concept model I will learn my lessons here, and do better on the next one.

Still debating what to use for the head...  it has to be slightly translucent, thin, and apparently taut enough when mounted.   Real hide would be nice, but I fear impractical.

Any ideas out there among the readers?

Off to the watchmaker's lathe to turn some ebony pegs...

20 Oct update -   Did not get to the pegs as expected, however one of my followers here and on CAMP passed a great idea for the head material.  She suggested I use real leather parchment and sent a link to a firm that provides various thicknesses (from apx 0.01" up) of calf, goat, deer etc.  They sell a 1 lb box of mixed scraps with apx 4 sq in ea, and 3 dozen pieces per pound for $25 plus shipping.

While I eagerly await it's arrival I decided to embark on a new project (a gig bag/soft case for the full size banjo)  as follows in the next post.   I will continue this one as it progresses.

6 Nov update...

I received the parchment and while thin, I do not think it is as thin as it needs to be.  I sanded a small piece thinner, soaked it in water and after cutting a hole in the lid of a snaptop container (for air flow for drying) I stretched the skin and snapped it shut.  I think this is going to work.  Photo results follow.

Results were quite promising.  I will have to make a form the same size as the rim with a close fitting outer ring to do the stretching of some even thinner skin.  I am not too concerned about perfect tightness as it will not actually produce audible notes with the strings I have, but this test gave me what I am looking for.

I have been slightly distracted by a new project idea and may be bouncing back and forth a bit.

Stay tuned...