Crawls Backward (When Alarmed)

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ca. 1931 Gibson TG-1 Tenor Guitar Assessment for Repair

A bit of a respite from the Saab dash.  Actually, the dash is back in the car - and the clock works (if you were curious), but I thought I'd write about something different before bringing those posts up to date.  Or something like that.

About 6 weeks ago (maybe longer...), a friend passed along her wonderful old Gibson tenor guitar for me to do some repairs on.

It's a ca. 1931-32 Gibson TG-1 to be more exact.  Early Gibby numbering doesn't enable one to pinpoint an exact year for the most part; we have to rely on features and what we know about FON (Factory Order Numbers) and serial numbers when (if) they are present.

This guitar has that fabulous late 1920s-early 1930s sunburst finish.  I'm not a huge fan of sunburst finishes, but Gibson's sunbursts from this time period up until about 1940 are just wonderful.

Plus this guitar has body and neck binding which has that nice old yellowed lacquer patina.  And check out that pointed end on the fingerboard, which Gibson reserved for its more deluxe models.

And then we have this fancy pearl inlay on the headstock.  This guitar was made during the 'transition' period where the older "The Gibson" logo was being phased out.  Guitars made during the early 30s may or may not say "The..."

And - an adjustable truss rod!

This is one of the things I'm going to work on.

It looks like the guitar sustained a hit on the top edge.  There are a couple of cracks that go through the spruce, but most of the damage is where the spruce sort of split and cracked upward.

One of the cracks has already been glued, and I'm going to see if I can get the others to lay flat and tuck back under the binding.

This damage actually looks worse cosmetically than it is structurally.

There are also three cracks on the treble side bout.  These go through the mahogany.  Should be easy to repair.

Here's a view of the top damage from the inside.

The green arrow is the one repaired crack.  It's not a big split at all.  The glue looks to me to be hide glue, which means the repair was done some time ago, and/or it was done by someone who knew what they were doing.  Very well done.

And surprisingly (and strangely) enough, there aren't any other cracks through the top - it seems that the spruce just cracked and bent up.  There is a top brace right under that area, which clearly supported the top when it was hit.

Gibson build quality was clearly not on par with Martin at this time.  The quality of the braces is good, but note the excess glue (red arrows).  You just don't see this on Martins from the same time period.

Two of the three side cracks.  Should be a straightforward repair.

Again, note the excess glue under the kerfing.

Here's the FON stamped on the neck block.  This number puts the guitar sometime in 1931 (probably). 

Now, to cook up some hot hide glue.


Saab 900 Dash Panel Recovering and Renovation

Finally got a chance to put the dash back together a few days ago.  It's taken a while because I'm thinking I should do it right while I have it all apart.  I don't want to take the instrument panel out again any time soon.

Which sort of reminds me of an old Peter Egan column in Road & Track magazine many years ago in which he talked about an MGB on which he "went to replace the brake master cylinder and wound up restoring the whole car."

This has bugged me since day one of ownership.  The PO used that awful Gorilla Glue to slap the UNLEADED FUEL ONLY badge on the dash.  We're going to fix that, I am certain of that.

I think I mentioned the peeling off/sagging vinyl dash trim.  That bugged me too.  I was planning to reglue it, but the more I peeled it back to get glue under it, the more it kept peeling and peeling.


Enter a brand-new dash trim piece!  Why try to clean up the old one when you can just put a new one on?

Grrrr.  A GM part sticker.

I recognized Rüsselsheim, Germany immediately as the location of the Opel car company (owned by GM since 1931!).

Before we can get the old covering off, we need to remove a few last pieces.

This is one of the power mirror switches - made in Holland by Mirror Controls International

It just pries out of the panel.

Here's the legendary 'beast' of the 900 dash - the panel rheostat knob. 

I got one screwdriver under one side, and a second one on the other side.  Couldn't get a picture because it popped off after some concerted levering.

It looks like I damaged it - but it's fine.  Just one tiny nick.

It's easy to get the rheostat off once the knob is removed.

And I do mean rheostat.  When you consider there are a number of 1 watt bulbs in the dash, there's a fair amount of current flowing through that circuit.  A regular pot would burn up.  I think there are 9 bulbs total - so there might be close to 10 watts of current draw.

The solution was to use a heavier control - a wirewound rheostat.  You can see the winding and the contact in this picture.

Now we can just pull the old cover off the dash.

It's held on with an adhesive on the back of the cover.

I take the time to get all the old dust and dirt off the switches and corners of the panel.

And I popped the two air vents off as well - they just clip on.

I soaked them in a weak mixture of Simple Green and water for about 30 minutes, rinsed them under warm water, and repeated.  They're nice and clean now.

It was a lot easier cleaning all the parts while the dash panel was off.  There are always some corners you can't reach while it's mounted on the car.

I also cleaned all of the switch contacts with contact cleaner. 

The new panel needs to be cut in a couple of places.  Namely, the mirror switches, and oddly enough, the dash panel dimmer.

I can see where the electric mirrors were optional on some cars, so those holes would be covered by the panel.  But you'd think every car would have the dimmer.

I traced the outlines of the cutouts onto the backing as you see above.

Then I carefully cut the panel with an X-acto knife.  This picture is misleading - I didn't do it freehand.  I used a metal ruler as a guide.  I did not want to ruin my nice new cover.  

I suspect the factory had punches to do these cutouts more cleanly than cutting them with a knife.

You can also see the paper covering the 3M VHB adhesive on the back of the panel.

It's easy to put the new cover on.  I peeled a little at a time to make sure it seated properly on the panel.

Then I pressed it down everywhere.  The adhesive is pretty tacky, but you can remove it and relocate the cover if needed.

Here's the finished dash panel.  You can see the holes I cut - I hadn't yet put the switches and rheostat back on. 

This is as close to new as you're going to get.

Oh, I didn't bother putting the ugly UNLEADED FUEL ONLY badge back on!  I just have a nice clean expanse of panel next to the radio opening now.  Looks a lot better I think.

A closer shot of the panel.  It looks great.  The fuzz on the controls is just lint from the cloth I used to clean them.

Next: back in the car and does our clock work?


VDO Quartz Clock Repair on the Saab c900

I suspect this will be a long-ish post.  I just uploaded 16 pictures!

Here we see the back of the c900 instrument panel on the bench in The Dungeon.  I'm going to replace the electrolytic caps for the clock in hopes of getting it working again.

If you do a search for "repairing VDO clock" on the interwebs, you'll find quite a few posts about how to fix them in your vintage Yurrupean car.  It seems the electrolytic caps dry up over time (surprise) and replacing them will fix the clock.  Let's hope so.

The blue circuit board you see above is actually flexible plastic, and it's attached to the panel with plastic pins.  The board has mating holes that just slip over the pins.  I say this because I've seen some ads for used instrument panels on the interwebs saying "board is not lifting" as a sales pitch.  For one thing, I find that hard to believe, since the whole thing is flexible.  Second, it will lift in spots - it's just its nature.  Doesn't mean anything is wrong with it.  It's the way it was designed.

If it was glued down, it would be virtually impossible to service.  And here I am proving that if the car lives long enough, it will need to be serviced eventually.  (And many of these cars have very long service lives indeed).

The tachometer and clock are in the leftmost (from the front) position.  There are 4 screws (arrows) holding the whole assembly to the panel.

You can remove this now or later.  I opted to leave them until the end, since they hold the panel in place, which is handy while you undo the instrument and clock screws.

Obviously this is for a Saab 900,  but the same basic approach should apply for any VDO instrument panel you may have in, say, a Mercedes, Porsche, BMW, VW, or that other Swedish brand that shall remain nameless.

You'll need to unsolder the ground pin for the clock.  Here I'm using desoldering wick to get it off.  I'm pretty sure it's a ground; in any event it has to be unsoldered to get the clock separated from the panel.

See also the yellow arrows - they're the locations of the tach and clock screws which also must be removed.

This assembly is fairly fragile - handle it gently and put your screws in a safe place.

I also highly enourage you to wear vinyl or nitrile gloves when working on the instruments to avoid getting oils from your hands on them.  You don't want to put it all back together and then see a fingerprint you left on the tachometer!

This assembly also has another tab (again, I suspect it's an electrical ground contact) that needs to be pulled up.  This connector holds a copper tab onto an instrument contact.

See what I mean about the circuit board?  You can see a mounting pin to the right of the pliers, and you can also see how it lifts a bit up off the panel in places.  It's the way it was made.

This is a shot of that clock pin/tab I unsoldered and removed earlier.

Now we carefully and gently can tilt the tach assembly up off the instrument panel itself.

The circuit board material will flex enough to allow you to flip the tach up over the board backward.  But be gentle

The arrows in the picture show the three screws that hold the tach and clock face onto the white mounting piece.  We need to remove them to get access to the electronics.

This is the clock assembly, and the silver Phillips can is one of the electrolytics we need to replace.  Use solder wick to unsolder the capacitor.

One note:  the hands on the tach and the clock will shift some when you have it all opened up.  Don't panic!  They're just not mounted to anything now that the screws have been removed, so they will just spin around some.  No big thing.

Handle the assembly with care - don't sit the face of the tach on something that will scratch it.  I was able to sit it on the panel in a way that I wouldn't move while I worked on it, and it wouldn't shift and get damaged.

The value of this cap is 100uF at 16 volts.  I went searching through my bin of low-voltage electrolytics and found a 100uF rated at 25 volts.  Perfect.

Here's the old cap shown with the new one that will replace it.

The new one is a bit thinner - and it's actually rated for 25 volts vs. the 16 volts of the original. Be sure to use a cap rated at 16 volts or higher.

I suspect a 35 volt cap might fit, but anything much higher will probably be too large.

Here's the new cap in place.  Be sure to observe the correct polarity - the circuit board has "+" and "-" markings.

I suggest using a good quality cap here - a cheap cap may fail and then you're back to square one.  I try to use higher end Nichicons or Panasonic caps in stuff I build or repair.  They cost just a few cents more than the cheap junk.

The second cap to replace is this 47uF electrolytic on the small board above and behind the tach.

It looked like the board would slide out - there's a clip on the back.  However, I couldn't budge it at all, and rather than risk breaking it, I just removed it from where it was.  A little harder to get to, but not too difficult.

The second cap replaced.

Note the little 'bins' where the warning lights shine through.  Maybe I should pop the upshift (NOW!  UPSHIFT NOW!) bulb out?

Nah, I pretty much ignore it anyway.  :-)

Reassembly is pretty much the reverse of disassembly.  The only semi-tricky part is getting the gauge to sit back down from where it came.

I found that if you gently move it around, it will find its seat easily.

Then put all the screws back in and button it up.  Be sure to resolder the clock ground and put that tab connector back on.

One last bit of maintenance before it all goes back together.  The dimmer rheostat for the instrument lights is to the left of the speedometer when viewed from behind.  These have a reputation for going intermittent, so I figured I'd clean it while I had access to it.

It just unscrews from the panel.

The sides are open, so it's easy to squirt a small amount (small amount) of cleaner in there.

Here's the instrument panel back together.  I'm going to clean and polish the plastic cover before it goes back into the car.

Before I put the tach back in, I hit it with compressed air to get any dust off it.  I also noticed there were small piles of dust on the inside of the panel where the clock setting knob and dimmer knobs pass through the plastic.  (There's enough clearance that dust can get in.)

So I took a vacuum and compressed air and got all the dust out.  Now it's perfectly clean inside.

Hopefully I'll have it back in place this week.  I'm putting in a second, calibrated boost/vacuum gauge and will do that while I still have easy access to the factory hose behind the dash.  Said gauge has yet to arrive at The Dungeon, so I'm in a holding pattern for now. 


Instrument Panel Removal on Saab c900

With the fascia removed, it's quite easy to take the instrument panel out.

First we need to remove the left-hand side speaker assembly.  There are 2 screws holding it in.  Take them out and pry the grill up.

Disconnect the speaker wires, and also wiring to the alarm LED (if you have one).

There are two connectors to remove from the back of the panel.  These are the electrical connector on the speedometer, and the speedometer cable.  You can see these highlighted by the red arrows.

The cable is the white connector - squeeze the tabs and it will slide out.  If you car is turbocharged, there will also be a vacuum/boost line going to the panel - it will just pop off when you slide the panel out.

Then remove the 4 screws in each corner of the panel which hold it in place.  These are T10s I think.

Notice all my labels for the center pod switches and bulbs. 

There are 2 ribbon connectors on either end of the panel.  Push push, wiggle wiggle, and they will slide off.

Now we can remove the entire instrument panel.

Again, that turbo vacuum line will just pop off when you take the panel out. 

I'm going to put a boost gauge in, so I'm eventually going to put a T connector in that line and run one end to the factory gauge and the other end to my new gauge which I have yet to acquire.

The passenger seat is still in The Dungeon, although it's ready to go back in.

In the meantime, I have plenty of space to store all the pieces I've taken off the dash :-)

Here's what it looks like with the fascia and instruments removed.  Controlled chaos.

Now we'll retreat to The Dungeon with the instrument panel and fix the clock.


Saab c900 Dash Fascia Removal

Lots of projects in the wings in The Dungeon. But while I have reasonably good weather here and can work outside, I'm trying to fix some stuff on Saabmarine #2.

I wanted to take care of a few things at once: the clock isn't keeping time (losing 6 hours a day!), the trim around the fascia/dashboard has pulled away in a couple of places, and I also want to service the instrument light dimmer.

What this means is I need to take out the fascia and the instruments themselves.

This might seem like a daunting task, but if you're patient and label everything, it's very straightforward.

There are four long bolts that hold the fascia to the dash. Two are on the left side of the steering wheel; you see them here.

Later cars (this one is a 1991) use Torx fasteners - these bolts are T15s.

Keep the bolts in order as you remove them. They are 4 different lenghts - they are also marked with rings to identify them (I'll get some pictures later).

Third bolt is to the right of the steering wheel...
...and the fourth is behind the ashtray. Just take the ashtray out and you'll be able to access it.

You may read in the factory manual or elsewhere that the steering wheel must be removed. Not so. There's plenty of clearance with the steering wheel in place.

With the screws removed, you'll be able to pull the fascia slightly away from the dash on the left side.

You can see that trim piece I need to reattach. I'm tired of looking at it hanging off like that.

I suppose I should have mentioned you need to take the radio out of the dash. I forgot, mainly because I took the old radio out a month or so ago. I'm going to put a new one in soon.

Here's the view through the DIN slot for the radio.

The screwdriver is pointing to the heater control rod. That needs to be disconnected.

Pull and wiggle gently on the control shaft and the swivel connector will pop off. This is what it looks like when it's removed - there is a flat metal tab on the heater knob, and the rod just clips onto it.

Next we need to remove the connector from the back of the air direction control. You'll see all of the vacuum hoses that run to it. Don't touch them! If you disconnect any hoses, you will have a heck of a time getting them back on.

There's a gold-colored clip that holds the connector to the body of the direction control. Just push back the top of the clip.

Here's the connector end after removal. Mine has red paint to identify the top.

The vacuum direction control is one of the things I love about old 900s. It's so much fun to switch the knob and hear the 'click-whir-whoosh' of the vacuum in the lines and the different flaps opening and closing.

I love using it, but I wouldn't have to troubleshoot all the lines. Fortunately, in the four 900s I've owned, that system has been very, very reliable.

Now that the heater control and the air direction controls are disconnected, we can move the fascia out a bit and get to the switches.
This part is very straightforward. I'm not going through it bit-by-bit. Basically you need to disconnect all the wiring for the dash lights and various switches.

In the picture above, the red arrow points to one disconnected switch - in this case it's the fan speed switch. You can see the mating connector tabs below it.

The yellow arrows point to some of the other connectors that need to come off. The switches will slide out from the front if you need better access to their connectors.

The best advice I can give you at this point is: label everything! And gently but firmly pull and wiggle connectors to get them out. If they are hard to disconnect, you may be able to use a small screwdriver as a lever to separate them.

Don't forget the headlight, seat heater control, fog light switch, and mirror switch on the left side.

With everything disconnected, the whole fascia/panel comes right out.

Remember: this car was built largely by hand. Yes, it was put together on an assembly line, but it was hand-assembled for the most part. That means it's relatively easy to take apart!

Next we'll get the instrument panel out.