In addition to making
protectors for
the vulnerable plastics, I also protected them by not peeling the white
paper backing off the back of the plastics (unless the plastic has a
clear section). This paper does not block the light very much, and
provides protection against abrasion from metal ball guides.
I
wish I had done this also for my MM plastic set. See the
IJ restoration on how to make
plastic protectors.
Another plastic that is frequently broken is the right inlane
plastic. The ball
hits the cantilevered end when it drops from the right ramp.
The
protector for this plastic
spans two bolts
and provides a bridge on which the
cantilevered end rests (
blue
arrow).
The new
skill
shot ramp from Kerry Stair has very sharp edges on the ball
guides.
The ball is lofted in the air by a launch ramp and then often bangs
against these edges. I
decided to find a way to prevent the ball from
constantly being nicked by this
edge.
Note that I have already installed a protector for the ball on the
side
fences (black plastic topping).
The ball guides were softened with clear tubing to prevent ball impacts.
The skill shot decals that I printed myself have been mylared along with
the entire horizontal tray. In almost all cases, the ball
does
not hit any metal.
The standard skill shot
ramp from
Kerry Stair has sharp edges on its metal parts. To prevent
the
ball from being constantly nicked, I decided to protect it from these
edges. A worn ball will more readily abrade the
playfield.
For the left and right side walls, I found that black grommet edging
used in the electronics industry works just fine. The curved
ball
guides were softened by using clear tubing cut lengthwise and then
pushed onto the ramp edge. Thanks to Kim (
Mr.
68) for this idea.
Note also the cobra plastic mod in the image above. The
original
cobra plastic is not very visible to the player, so I printed the scan
onto some white photo paper and then fastened it in front of the
bulb. The new decal is just folded along the metal edge, and
when
the glass is slid back into the machine, it folds the decal
back.
Speaking of the bulb, this item was vulnerable to vibration, and would
blow out every few weeks. I fixed this problem by fashioned a
shock mount from some rubber grommets on the mounting tab of the bulb
holder. Normally, there is supposed to be a green cover on
the
bulb, but I opted to not install it. The decal hides the
naked
bulb from the player.
Top view of left diverter. Note the use of adhesive rubber to
protect against metal-metal contact.
The haze on the playfield is due to the top two loops being mylared.
There are two diverters
in this
machine. To prevent damage from
the flapping of the metal guide, a small rectangle of adhesive rubber
was used in both locations. This prevents
metal contact every time the diverter activates. One other
example is the metal diverter that flaps onto the plastic swirl ramp.
Fuse F104 investigation
After playing our first few games on the newly restored machine, F104
blows as soon as the ball passes the magnet ramp (when the magnet is
energized). This fuse does not blow in test mode.
In
investigating this problem on RGP, I found some interesting questions
being raised about this fuse. They were:
- What
is the proper part to use for F104? Depending on
where you
look, it can be specified as a 2.5 Amp SB (slow-blow), 4 Amp FB
(fast-blow), or 4 Amp SB. The fuse I was using was a 4 Amp FB.
- When F104 is blown, and the Ramp
Magnet (Solenoid 8) is
tested, it is the Ramp Diverter (Solenoid 21) that
fires! Why
is
that?
- When F104 is blown, and you disconnect the Ramp Magnet,
when the
Ramp Diverter is activated, it stays pulled in. Why?
Here are the results of my investigation:
Question 1:
What is the
proper size for F104? Answer: Using a clip-on DC current
probe,
the
current
pulse (in test mode) through the ramp magnet is shown below.
Current trace through the Ramp Magnet (Solenoid 8) in test
mode.
Note peak current of about 10 Amps, and the
ripple of the full-wave rectified 60 Hz line power.
Looking at the blow
curve of
fast
blow
fuses, and
slow
blow fuses
we can understand how long the fuse will sustain this 10 Amp
current. The data is summarized in the table below.
Type
of Fuse
|
Average
Blow
Time @ 10 Amps (sec)
|
4
Amp SB
|
4
|
4
Amp FB
|
0.2
|
5
Amp FB
|
0.4
|
6
Amp FB
|
0.8
|
I would prefer to use a fast blow fuse if possible. That
sentiment is shared by Martin Reynolds, another RGP member with
electronics experience. After trying a 5 Amp FB (which was
not
successful), I installed a 6 Amp FB. After a few games, I
realize
that the Ramp Magnet is energized for as long as 2-3 seconds
(!).
It remains to be seen if the FB fuse will survive. Updates to
come in the weeks ahead.
Question 2:
Why does Solenoid
21 fire when F104 is blown? Answer: The schematic below was
obtained by
tracing the wiring in the machine and consulting the schematics of a
WPC-95 machine. Note that the protection diode D41 is not
directly connected to +50V, but is connected via F104 (!).
When
this fuse is blown, and the Ramp Magnet is activated, the two Solenoids
are put in series and connected to +50V. This is the reason
why
Solenoid 21 fires when F104 is blown. The current path in
this
case is marked by the dotted line.
Current path when F104 is blown and the Ramp Magnet is
activated.
It causes the Ramp Diverter to pull in.
Question
3: Why does Solenoid 21 stay pulled in when the
Ramp
Magnet has been disconnected? Answer: Note that in the
circuit
above,
that the coil collapse current is passed through the ramp
magnet.
If this magnet is disconnected, a potentially very large voltage can be
created at the anode of D41. This may cause damage to Q26,
and is
probably why S21 stays energized if it is pulsed when S8 is missing.
The original speaker inside the cab had a rip in the surround, and
suffered from low output. I decided to replace it and
to boost the output of the cabinet amplifier.
Cabinet with new bass speaker, a 6.5" woofer with a beefy 20 oz magnet.
The
speaker
I selected cost $17, has a low frequency cutoff at 41 Hz, and
an
efficiency of 85 dB. Unfortunately, I overlooked that this
was
meant for home audio applications, with an impedance of 8
Ohms. A
better choice would have been a 4 Ohm unit such as is typical with car
audio components. However, it fit perfectly, and I decided to
use
it. Sites such as partsexpress
have car audio speakers, and a 6.5" woofer with an efficiency
of
greater than >=90 dB and a cutoff of <=35 Hz can be found.
Closeup of the corner of the audio board where the bass boost mod is
installed. The boost resistor can be easily changed.
WPC-95 machines such as
TOTAN have a
separate amplifier for the cabinet speaker. To compensate for
the
speaker's impedance and to increase the bass level, I reduced the value
of R41 by putting another resistor in parallel with the existing
one. This was done by soldering two machined pin IC sockets
on
the leads of the resistor so that I could easily change the value by
plugging in a resistor. On the Medieval Madness, this
additional
resistor was 330 Ohms. On the TOTAN this was set to 110 Ohms.
The result was a nice increase in the low end with lots of rumbling and
vibration when the Genie spoke and the pop bumpers are hit.
Not
as dramatic an increase as on the MM, but a nice addition nevertheless.
A new home
In 2010, I decided to change the collection a bit, and decided to sell
my TOTAN. My game room is in my basement, and access is via
an
exterior set of stairs that has a sharp 90 degree turn at the
end. Getting machines in and out has always been a big
challenge,
but over the years, I developed some tools to improve access.
We started by supporting the backbox end and removed the legs.
Then, the cab was tipped back and the front legs removed.
The first improvement
measure is a
'stair
climbing' hand truck
that was purchased for $100, and my first use on a pinball machine at
this occasion. I thought it would be too short at
40",
but as it turned out, the resulting geometry is just fine. In
the
photo below, the machine's center of gravity is balanced over the
wheels, so I am not bearing its weight, yet I can easily control
it. Two people are needed to 'break it over' from the
standing
position due to the large size of the wheel mechanism, but once
it is up, it balances just fine. It has a weight capacity of
600lbs.
The machine balanced on the special hand truck.
The design has six
tumbling wheels
that prevent the need to dead lift the load up each tread of the
stairs. At least that is the intended result of the
mechanism. Of course, I could have purchased a motorized hand
truck such as an Escalera, but they cost as much as a pinball machine,
and I would only use it very rarely.
This is the sharp turn at the bottom of the stairs.
The second improvement
measure is a
platform that drops down and covers the floor of the landing at the
bottom of the stairs. This is because that bottom most level
is
too small to make a turn with a pinball machine that is sitting on a
hand truck. This platform increases the area considerably,
and
makes it possible to make the turn. It also removes the need
to
step down when leaving the basement.
Another view of the machine on the platform at the bottom of the
stairs. Note the winch cable at the bottom of the image.
The final improvement is
an AC
powered 1500 lb capacity winch that is fastened to
the wall of the basement stair well. Combined with the
tumbling
action
of the 6-wheel mechanism, it should allow the machine to be winched up
smoothly. The winch has a remote pendant, and cost $90.
View of the winch routing to pull the machine up the stairs.
I put a rope around an
oak tree that
is at the top of the stairs, and hooked a pulley to it. The
pull
cable then runs from the winch through the pulley, and then down the
stairs after riding on a cardboard pad to prevent scraping on the
concrete of the top stair tread. The pull cable is then
hooked to
the metal structure of the hand truck.
Close-up of the
winch
from Harbor Freight Tools.
We got set up at the
bottom of the
stairs, and starting putting tension on the pull cable. After
lifting the machine by one inch, we bounced it up and down a little to
make sure the weight was not a problem. We then slowly
winched
the hand truck up. It became apparent that the action of the
tumbling wheels was very smooth, and very little additional tension was
needed to climb each tread. With lots of stopping and
pausing, it
took only three minutes to climb the stairs. With experience
that
could be cut down considerably.
The new owner Bruce at the top of the stairs. He said it was
very
easy, and
he just had to balance the load.
A discarded alternate
concept of
this winching system was to build a
sled that would roll on two wooden beams up and down the
stairs.
However, I
decided against this due to the bulk, but also because once I arrived
at the top of the stairs, I would have to transfer the machine from the
sled to a hand truck anyway. So I figured it best to strap
onto
the
hand truck from the start.
Good bye TOTAN. You go to a good home.
The entire operation starting with the loosening of the first leg bolt
to closing the gate on the truck took a total of one hour.
