18 December 2017

A day in the life... Leaf Battle

In this late fall season there is a battle,
a consistent yet finite barrage of falling leaves.
The ground crew is hindered 
by the suffocated grass they try to protect,
as the ground is too soft for faster but heavier equipment.
Ruts are bad.
Here the tools of choice are backpack blowers,
and possibly these gas powered side blowers.
Funny thing is all three were broken.
Bad head gasket on #1,
bad exhaust manifold/muffler on #2,
and a coil on #3.
The coil was easy,
I just swapped one from the bad head gasket donor.
The guys were all over it,
justifying the fix of the other two.
The replacement exhaust manifold had a screw on outlet,
but nothing to screw in.
I raided the scrap pile for tubes and pipe fittings,
and welded up a custom muffler.
All that practice with hot rods, boats,
motorized bikes and scooters...
The new silencer worked perfectly,
quieter than most of our engine tools here.
The first day went well,
other than the mini front roller digging into the soft grass.
No problem.
Some quick brackets and a fat roller wheel...
Zip zip with a welder and voila!
Now get out of here and start blowing leaves...
There are acres of leaves...
To pick them up.
there's a Toro Rake-O-Vac,
basically a trailer vacuum/rake,
that hadn't worked in a couple years.
New battery,
an overpriced coil,
and this was good to go.
It works great on unpiled leaves.
One of the guys pulled a full load to the compost area,
hit a whoop-de-doo in the road,
that opened up the trap door,
spilling a compacted pile that took 2 hours to clean.
Now nobody wants to use it!
Then they dug up this thing,
a stadium vacuum,
previously attached to a broken buggy.
It worked great til the hose broke for the umpteenth time.
The fallback is the good old pitchfork.
Manual labor at its finest.
Scoop by scoop...
the leaves slowly disappear.
Until one of the trucks takes a chit.
A busted starter allowed the fix of a lingering oil leak,
probably the rear main seal.
This meant tearing out the transmission,
fun on a 4x4 with a transfer case.
Years ago work had traded a local junkyard a broken vehicle,
for this ford ranger which had a bad transmission,
along with a replacement.
The previous mechanics got it running,
but cranked every bolt so tight they were barely able to unthread.
The exhaust wouldn't come off without breaking a bolt.
To make room I cut and hammered the welded seam lip,
visible on the top there.
While I did technical stuff 
like cut out a hard to find gasket...
The outside guys laid around.
It wasn't much fun putting this together,
but there was success getting it running.
Time for something fun.
I found a scrap bumper in a metal pile.
It was set aside for this truck,
but nobody could cut and weld here.
Some crude bracketry...
Cut cut Zip zip...
Now we could push gates open,
and move trash cans around.
Didn't take long to get it back to work.
Seriously there are tons of leaves here.
They'll get composted into the mulch pile,
and eventually returned back to the earth.
I still need to get the 3rd blower working,
too late for this season.
At least everything is green again!

10 December 2017

Scott LK-72 - rebuild

What's happening.
I'm turning into one of those tube stereo geeks.
With the dark almost winter hours upon us,
instead of rushing home and working on a hot rod,
I look forward to sitting at our converted bar,
eyeglasses on,
maybe a drink - maybe not,
whittling away playing with wires and electrical stuff.
Strangely enough,
wiring a car isn't even my favorite thing to do.
I'm too picky and it's tedious,
but I'll do it,
and when everything works it's a big win.
This Scott LK-72 integrated amp 
was sold in the 60's as a kit.
A budget way for an electric geek to have tunes.
The factory wired model was the Scott 299C,
which had a gold face instead of poop brown.
Of course I ended up with a cheaper project...
Over the years electrolytic capacitors tend to dry up,
or in this case leak.
That's the tan powdery residue.
These are multi-caps,
can capacitors that are a compilation of values.
Post-war technology made this easier,
most likely a byproduct of all the WWII factories
that needed to continue churning out hi-tech chit.
There's two main methods to repair these.
Buy replacements if possible,
they are usually plastic wrapped black or blue,
and possibly a little different size 
needing different mounting clamps and holes.
The second way is way more fun.
Dig out the insides,
and replace them with new capacitors,
shaped like little batteries.
From the top everything looks original.
This involves grinding, fitting and thinking...
Like hot rodding but tiny.
Here there are ways to modify the ohm values,
online forums have high-priest geeks 
that give out loads of info.
For now I'm just a swapper.
Let's hear what new stock woulda sounded like.
Somehow that pile above equals this.
The roll of aluminum foil and electrolytic
is separated in 4 pieces.
These things basically are filter caps,
cleaning and storing the necessary power.
They call this silver box a toxic grenade.
It's a selenium rectifier that converts AC power to DC.
Supposedly not the best stuff to breath in
if it blows up.
Now swapped for a silicon bridge rectifier,
the black thing with the 4 prongs.
The suggested 1 amp replacement 
was smaller your pinky fingernail,
not much to solder fat wires too.
This is a bigger 4 amp version.
Now the tedious part,
replacing a bunch of single capacitors,
those white tube things.
I think there were at least 22.
Again replacements were much smaller,
with tolerances much tighter.
The tipping point...
Where's that drink now!!
Will it poof or perform?
After letting it run for hours on test speakers,
it was time to power up the Klipsch/JBL thumpers.
Oh yea...
Sweet sound,
without the overheating it had when first bought.
Next up was hammering out a quick shield.
Too much voltage and glass in there,
an accident waiting to happen.
Originally these came with a louvered sheetmetal box,
that seemed to collect too much heat.
The taller screen allows another geeky thing,
tube rolling.
This is dangerous as original Mullards, sylvanias
telefunkens and GE's etc can be $50-100 a piece!
Fortunately there are new east European versions,
much cheaper.
The main power tubes are 7591's,
made from a variety of manufacturers,
and sizes vary.
The original bottom RCA's were much shorter.
I screwed up and bought the larger ones on top,
but they (electro-harmonics) didn't fit.
We'd go with the center JJ tube,
and wow I can't complain with the sound.
The 12ax7's are the preamp tubes,
kinda the sorters that refine the sound.
Most say these are the most important,
as they can limit the gain or volume,
and their sound is amplified both good and bad.
There's a lot of info on the many variations.
I went with new sovtek 12ax7lps,
supposedly the best budget tube.
And check out these boxes!
Instead of adding a separate insulation wrap,
a 5th lead is folded in,
safely cradling the tube for shipment.
I warned you it was geeky!!
You should read online forums,
there's diehard viewpoints about this tube stuff.
The amp had its time to shine,
and man it did.
However deep down I knew it was unfinished.
If you look at the 2nd pic,
there are 4 can capacitors,
and I only redid the obviously leaky 2,
although there are parts for all.
The third one went much quicker,
with a cleaner wiring trick for the ground.
I almost want to redo the first one.
For now my OCD stopped at the 4th one.
I'll have to mentally prepare for it later.
Let's wrap this up!!
Lastly taller feet were added,
more air should flow...
And a nicer faceplate was found.
The original had an annoying scratch.
The paint is sooo thin.
And here we are!
About an 80% rebuilt unit.
Are you ready for a holey chit yet?
Oh yeah...
A semi-matching tuner was on Craigslist,
but it was incomplete and a gamble.
I ended up flipping it which paid for the tubes.
Super stoked on the sound.
It's not as muddy or thick as before.
Not quite the warm sound people rave about,
but the Scott's weren't known for that.
They have a real uncolored sound,
like that's what it's supposed to sound like.
Yea geeky chit...
Thanks for reading!!