Crawls Backward (When Alarmed)

IconProjects, musings about guitar builds, guitar repairs, vintage tube amplifiers, old radios, travel, home renovation, and other stuff.

Attack of the Hummingbirds!

I was in the desert for the last five days.

Some friends there have a couple of hummingbird feeders and I managed to get pictures of those amazing little things! 

If you've ever seen hummingbirds in action, you know they just zip around at super fast speed.  Hard to get a close look.

I saw five or six different ones, I think.

Most of them actually stopped and perched for 30 seconds or so to load up with nectar from the feeder.

Most of them have quite striking colors, but some of them are relatively plain.  I wonder if the females are the plain ones - that's the case for most bird species, I believe.

Look at how large their wingspan is.  When you see them fly, their wings are going so fast they look like dragonfly wings.  But they're pretty conventional once you see them sitting still.

I saw this cool green one a number of times.

Lookit his little claws.

You can see this one's tongue out of his bill.  They use their tongues to drink.

I wonder if they ever sleep.

This was one of the coolest ones, but it was also very hard to photograph.  He wouldn't land on the feeder - he would just suspend himself over it and feed.

This one also did the 'flying while feeding' thing.

Aside: all of these hummingbird pictures made me think of my hummingbird toy.  (I wrote that post six years ago!)

Here's that purple-headed one actually feeding.  Look at those wings go!


Headstock Veneer Replacement on Princess Banjo Mandolin

You may recall in our last episode we were left hanging with a new piece of rosewood glued to the back of the peghead.

The piece was more or less rectangular shaped and overlapped the peghead so I could trim it back.

This gives you an idea of how much I had to work with.  You can see the long section has already been trimmed - this contoured section at the top remains to be done.

I used a couple of small files and 220 grit sandpaper to trim the excess.

And here it is finished.  I still need to smooth it out a bit more, but it's there in terms of the shape.

I think this is going to work.

Lesson learned:  don't try to remove old veneer to fix cracks.  Leave them on the instrument and fill them.

There is a seam between the old veneer and the new.  The old piece is about .058 of an inch (about .58mm) thick, and the new one is about .010 thicker (.1 mm).

I just block-sanded the new piece down to the same height as the old one so it would match up.

Here it is.

I think this is going to work out.

Fortunately the original pieces were black.

I filled the seam with rosewood filler, sanded it flush and then used Fiebing's leather dye as a finish.

I had also sanded the old finish off the mating piece on the "heel" of the headstock.

The dye is like stain - messy, goes everywhere and will spread like crazy through porous surfaces.  I spread some on the top, and used a very fine paintbrush for the edges.

Came out well I think.

Now I'll spray clear nitro lacquer over it as it had been finished originally.  I think it will look good.

Just need to wait until the humidity outside drops some so I can spray outside.


Headstock Crack Repair on the Princess Banjo-Mandolin

There are some cracks on the headstock veneer plates that I want to fix.

There are veneer plates on both the front and back of the headstock.  So I need to remove the tuners to get at the back plate.

The construction of the head is a little unusual.  Not only are there two plates, there is also a large cutout to fit the tuners.

The tuners are made by Waverly - high quality.  This is one interesting instrument.

You can see how the head is a sort of "T" shape, with the front veneer covering the open space.

Here's another picture, this time with both sets of tuners removed.  The headstock is part of the neck as far as I can tell - both the neck shaft and the head are maple.  I don't think there is a scarf joint there.

But I could be wrong.

So I had this bright idea (right) to remove the veneers in order to close up and glue the cracks.

The front veneer was easy.  It's pretty thick.  Although, the cracks closed up just a little.  Probably should have left it on the banjo-mandolin.


It gets worse.

I had a heck of a time figuring out what kind of wood was used.  I finally took a shot and used some rosewood filler.

It worked fine, and I'll be able to sand it smooth as the bottom of a baby.

Then I think I'll shoot some nitro over it.

As for the back veneer...
...I tried to take it off with my usual heat-and-knife approach.  The approach that has never failed me.

Until now.

The veneer is/was so thin that it just shattered into a gazillion pieces.  What was I thinking?  Why didn't I just fill it?

I guess I got crack-fill happy.

In the picture here, I'm measuring a piece of the shattered veneer.  Yes, it's merely .047 of an inch!  (1.19mm).

So I took a piece of rosewood headplate stock which started life at about .090 inches (2.29mm) and sanded it on the ROSS down to about .055 inches.  It was very fragile at that thickness so I didn't dare go thinner.

Then I glued it up to the headstock.

I'll stain it to match the trim on the neck and hope for the best.  I think I can recover from this stupid goof.  Hopefully.

To quote the legendary philosopher Bugs Bunny, "Eh, what a maroon!"


Installing Oil Pressure Gauge in the SAAB c900

I'm waiting on some bits for the banjo mandolin, so I needed to find some other project to work on.  I have a short list of stuff left to do on the SAABmarine, so I worked on a couple of things.

One of them is actually connecting the senders/sensors for the oil pressure and water temperature gauges.  You may recall that a while back, I put the gauges in the dash, and ran the tubing for the gauges, but didn't connect them.

I'm going to connect the oil pressure gauge first, since it will be a bit less daring than the water temp.

We need to remove the factory oil pressure warning sender.  First, we disconnect the hot lead from the sending unit.  You can see the blue arrow pointing to the connector - I've already pulled the wire off at this point.

You can also see the sender has a big hex on it - which is what we'll need to undo.

Digression here: for those of you who own (or have owned) English cars with wire wheels: you know about 'undo' - it's on the wheel nut with an arrow indicating which way to remove the nut.

Do Ferraris with Borrani wheels have a similar instruction?  I have no idea.  I have never had a tool in my hand within striking distance (ha ha, striking) of a Ferrari.

The nut is 24mm.  I suppose you could use an open-end wrench, but as a relatively experienced SAAB mechanic, I have the proper tool - a deep-well 24mm socket.

The perfect thing for the job.

Funny how that wide angle setting on the camera lens makes close-up stuff look huge.  That wrench looks like it's about 50cm long!

Or the car has suddenly shrunk.

Here's the sender after removal. Piece of cake.

Mmmm.  Cake.

Now, this is the factory sender for the oil warning light on the dash - the one that lights up when your oil pressure is like 5 lbs or below.  Meaning: Stoppa motorn nu!

I am basically daring to run without a warning light.  I actually have a bunch of adapters which will let me use the new gauge connectors AND the factory light, but right now, I'm just connecting the new gauge.  Time will tell if I bother to reconnect the old warning light. I'm starting to think since I have a gauge I'll be ok.

Here's the new connector that goes into the engine block.  There's a little brass ferrule that goes over the hose and seals the thing up tight.

Then the outer nut tightens up over it.  The business end screws into the block.

We need to put some thread sealer on the threads so they won't leak.  This is a mechanical gauge, so oil goes into the hose.  We don't want leaks.

I tightened the block nut first, then the top (hose) one.

This picture makes it look so easy, doesn't it?  Let me tell you, this was a beast.  I could only turn the nuts about a quarter of a turn before the wrench contacted the dipstick tube.  Took a while to get them tightened up.

We don't need a lot of torque on these pieces - the little ferrule might get crushed.  We have to treat the ferrule with caution, bless its little brass head.

The gauge end, inside the car, is a whole lot easier to connect, since we have complete access to it.

Again, don't want to tighten it up too much.

And use sealant on the threads as well.

Remember when I said oil runs in the line?  Well, here it is!  (Blue arrow points to the oil line).

You can see there are no leaks.  The hose has a fairly thick wall, so it's unlikely it will ever leak along its length, and there aren't any places where it makes a tight bend or contacts something sharp which might cut or abrade it.

Also, it's not hot at all - by the time it travels through the hose it cools down.

When the engine is off, the oil goes back down into the engine.

Crazy, huh?

Generally speaking, main difference between this mechanical gauge and an electrical one is accuracy and reliability.  An electrical gauge relies on a sensor which may not be accurate, lose its accuracy over time, or fail entirely.

With a mechanical gauge, we eliminate the sensor, and the gauge itself is reading the pressure directly.

Trollhättan, we have oil pressure!

The car was starting to warm up at this point.  From cold, the pressure is about 60-62 psi.  It drops to about 20 psi at hot idle.


Vintage Princess Banjo Mandolin Crack Repair

Now that the Princess banjo mandolin is lying in state pieces on the workbench I can start fixing the cracks.

First one is this crack on the heel cap.  The cap is a nice pice of birch I think.  It looks like the laminate in the center of the neck underneath began to crack and took the cap with it.

This shot is a little out-of-focus, but still illustrates the point.  You can see the split where the laminate piece - I think that's birch also - began to crack.  Since the cap is glued to that, it also cracked.

So I got some hot hide glue into my syringe.  I'm using a 0.9 mm needle.  I had to thin the glue down - it's not quite water-thin, but close.

The glue has to be thin or it won't pass through the needle.

I squirt the glue into the crack until it starts coming out of the top.

Then I clamped it up in a vise with come cork-faced cauls.  The white paper you see is waxed paper, so the glue won't stick to the cork.

It's hard to tell, but I think the crack on the cap isn't closed all the way.  We shall see what happens.

The next crack is this one on the maple trim piece that covers the laminations on the rim - see the arrow in the picture.

I was gently pulling on the crack to see how far the piece was pulled off the rim.  A couple inches...couple more.  Then, small crack noise and the whole piece popped off.

It's actually better that it came off.  Now I can reglue the whole piece and know it will stay on.

I glued the ends of the trim piece together and clamped them down to dry overnight.

Then I'll be able to attach the piece onto the rim as one assembly, rather than try and deal with the crack at the same time.

The round trim piece is sort of 'springy' and isn't exactly the same size as the rim.  In other words, I have a bit of play in terms of its fit.

So I'm going to glue a small section at a time so it will line up properly.

Brush some hide glue on the rim...

...and align and clamp down that section.

I left this piece to dry and the next night did another small section.  And I started thinking: this is going to take a week at the rate I'm going!

I kept thinking to myself: "self, if you only had a bunch of spool clamps to do this, you could do the whole thing at once!"

Then it hit me: I don't have spool clamps (yet...) but I do have rubber bands!

So I used rubber bands to hold the rim down, with clamps in a couple of recalcitrant sections.

It worked great.  Got it lined up all the way around.

Do you remember the crack in the heel cap?

My first repair closed the crack in the heel itself, but only tightened up the heel cap a little.  I thought that might happen.

So I used my Crawfish Instruments Bridge and Veneer Removal Iron™ to heat the cap.

Careful use of a seam separation knife gets the veneer right off.

Now I can fit the two pieces back together properly.  Which is what I should have done the first time.

Here is is glued up (again).  Should be much better this time.


ca. 1935 'Princess' Banjo Mandolin Restoration

Who woulda thunk it?  Two mandolins in two weeks?

And this is not just any mandolin - it's royalty! 

Not only that, it's a banjo mandolin.  As if a mandolin wasn't loud enough to start with.

This is a sort of mystery-make banjo mandolin.  I'd guess it dates from the late 1920s maybe up to 1940 or so.

Told you it was royalty!

It's a 'Princess.'  Very nicely made - 5-ply maple rim, three piece maple and rosewood neck, and what appears to be a rosewood headstock inlay.

I suspect this was made by Regal or one of the other Chicago makers - there is a plate covering the rear of the tuners that sure looks Regal-esque.  Plus, the name could be a play on 'Regal' as well.

At any rate, it belongs to a friend of mine and I'm going to do a little fix-up and get it going again.

There are a couple of cracks to fix, I'm going to put a new head and possibly a bridge on it as well.

First order of business is to take the head off.  I'm using my new 'MyBanjo' tuning head wrench.  Pretty neat and handy - three common sizes on one wrench.

The lugs were pretty loose - virtually no tension on the head.

I need to take the neck off in order to remove the head.  There is a lug at the strap end that attaches to the coordinator rod.

The rod isn't adjustable, but it's not made of wood, so I think the proper term is coordinator rather than 'dowel.'

OMG.  I am speaking banjo language.  We're in trouble now.

You can see how I just used the lug itself to turn the nut that attaches to the rod.

Here's the lug detached from the pot and the rod.

I'm leaving the other lugs on for now.  I'll polish them, and I think it will be easier if they stay on the banjo pot.

Closeup of the MyBanjo tool.  I believe it's an English design.  This should fit 95% of the banjos in existence I would think, since there are three nut sizes - 1/4, 9/32 and 5/16.  Imperial measurement still lives!

If you have one of these, you will be able to tune the head on virtually any banjo on earth.  That, my friend, is power.  Use it carefully.

I bought this and the new head from Elderly Instruments. And ironically, my friend, whose banjo mandolin this is, worked at Elderly in the early 1980s.  Small world.


So now we can just pull the neck away from the pot.

When I did this, I thought of another good friend who says "Banjos are easy to work on.  They're just a bunch of parts."  And so they are.  And it's pretty logical as to which part goes where.

The internal rod just slides out from the bigger coordinator (or is it just a rim?) rod.  There's a thread that goes into the neck heel.

With all of the tension lugs undone, it's a simple matter to pull the tension hoop up off the head.

And the head just comes up off the rim.

There was a spot at the heel end of the neck where the fingerboard was pulling up off the neck.  So I just gently tugged on it, and the whole board came off.  Better now than when my friend is in the middle of some fingerboard-burning solo.

The frets are really sticking out from the fingerboard, so it will actually be easier to dress them back with the board off the neck, I think.

Check out the beautiful black and white pearl "moon" inlays.  Very nice.

Next, I'll work on those cracks I mentioned.