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I acquired my L-3330 on eBay in 2004.
The right-side of the L-3330 is an irregular-shaped steel casting that forms the main body and rope channel for the device. In back, the casting has two ears drilled to support a roll rivet and a U-channel guide roller below the rope cam. Extensions toward the front support the left side plate, which is made from 1/8" (3.2-mm) steel riveted into place with three roll rivets.
The top river supports (1) a spring-loaded stamped extension arm with an upper U-channel guide roller enclosed, and (2) a short arm that acts as an upper cam face guide.
The middle rivet supports a spring-loaded cam lever, which is attached to the cam face with a 9-mm steel pin (held with an external retaining ring). The other end of the cam arm bends downward, where a 16-mm hole provides a tie-in point. The cam face is straight with 12 flat teeth formed by shallow 1.5-mm U-shaped grooves centered 3.9-mm apart.
The third rivet supports a loose block that serves to partially block cam opening if the device is upside down, helping to avoid rigging the device upside-down.
A small spring-loaded lever rides on a pin below the cam lever. This pin actuates a small cam that keeps the main cam from opening. To rig or derig the device, one must depress this lever.
The main casting has an upward-pointing arrow and "UP," "HAUT," "AUF" and "ALTO" cast near the rope admission opening. The sticker has "RM-3340" printed vertically at the right edge. The main text reads as follows:
LAD-SAF®
MODEL L-3330
SERIAL NO.
S64491
DB INDUSTRIES, INC.
RED WING, MN 55066
DBI/SALA ™MADE IN USA
ANSI A14.3U.S. PAT. NO.
5,265,696
WARNINGREAD AND FOLLOW INSTRUCTIONS
SUPPLIED WITH THIS PRODUCT BEFORE USE
FAILURE TO DO SO COULD RESULT IN
SERIOUS INJURY OR DEATH. THIS DEVICE
MAY ONLY BE USED AS PART OF A DBI/SALA
APPROVED LADDER SAFETY SYSTEM. THE
CABLE AND THE HARNESS OR SAFETY BELT
ATTACHMENT POINT IS 9 INCHES.
INSPECT THIS DEVICE PRIOR TO USE.
The right side of the cam is stamped "94102301." The left side is stamped "FOR USE ONLY WITH 3/8" DIA SOLID CORE CABLE."
The LS-58 is protected by U.S. Patent 5,265,696.
The L-3330 is designed for use on steel cable, not rope. I do not like this idea; rope provides a shock-absorbing capability that steel cable does not. This is probably why DBI/SALA limits the lanyard length to 9 inches - to ensure that no one takes a significant fall. This would only work if the cable is tight to begin with - for example, tightly anchored both top and bottom.
I did not show the L-3300 open for rigging since one merely depresses the lever on the left side and opens the cam, without having to remove any pins or disassemble the device in any way. This is easy to say, but rather awkward in practice. The release lever that allows opening the cam is small and in an inconvenient location and the cam spring is strong enough that one wishes for a third hand to help hold the body, cam. lever. and cable all in the proper alignment for rigging.
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I acquired my LS-038 on eBay in 2004.
The body of the LS-038 is formed from 1/8" (3.2-mm) stainless steel bent into a 5/8" (16-mm; internal width) U-shape. There is a second, much smaller U-shaped piece welded to the bottom. This is drilled to accept a 4.5-mm rivet, which mounts a 7.8-mm wide roller. The roller has a U-shaped groove turned in it, giving the roller central and peripheral diameters of 12.9 and 14.4-mm, respectively. The shell has two sets of 11.5-mm holes that accept 11-mm diameter, 23-mm working length quick release pins to support the internals assembly. A lightweight wire chain attaches the quick-release pins and internal assembly to the shell so that the user does not drop individual pieces while rigging the device.
The internal;s assembly consists of two cast stainless steel pieces and a variety of minor parts. One piece forms the cam face that bears against the rope. This piece is 115-mm tall. The top has a cutout to support a rivet and roller. The roller is similar to the shell roller. The back of the cam face piece has an angled notch that engages the upper quick release pin in a way that allows the cam face to slide upward and toward the rope when the device is loaded.
The second internals casting is a cam actuation lever. It pivots on the lower quick release pin. The interior end fits in a groove cut in the lower half of the cam face piece. This groove extends through the cam face piece to the rope contact surface. A spring connects the lower part of the cam face piece with the base of the cam actuation lever. This provides pressure to help keep the cam face against the rope.
The cam face piece has an arrow and "UP" engraved on both sides.The left side of the shell has a yellow sticker which reads as follows:
LAD-SAF®
WARNING
READ AND FOLLOW INSTRUCTIONS
SUPPLIED WITH THIS PRODUCT BEFORE
USE. THIS DEVICE MAY ONLY BE USED
AS PART OF A DB INDUSTRIES
APPROVED SYSTEM. ANSI A14.3
SERIAL NO.
S53919
DBI/SALA ™
DB INDUSTRIES, INC.
RED WING, MN 55066PAT. NO's. U.S. 3,979,797;
4,071,926; 4,193,475 CAN.
1,037,000; 1,052,340;1,102,288
The right side of the shell is stamped with an arrow labeled "UP", "HAUT," "AUF," and "ALTO" and with the message, "LS-038 FOR USE ONLY WITH 3/8 solid core cable.
The LS-038 is protected by U.S. Patents 3,979,797, 4,071,926, and 4,193,475.
Like the L-3330 , the LS-038 is designed for use on steel cable, not rope. As I said there, I do not like this idea; rope provides a shock-absorbing capability that steel cable does not. In this case, DB Industries did not provide any warnings or limits on lanyard length, but I believe that they should have.
The lower roller seems rather narrow.
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I acquired my LS-58 from John Murray in 1993.
The body of the LS-58 is made from two pentagonal pieces of 1/8" (3.2-mm) separated 20.5-mm by a strip of the same material forming a cross piece on the left and a 12.5-mm pin welded forming a tie-in point at the upper right. The cross piece that forms the back of the rope channel. The other side of the rope channel is a hinged cover extending half the height of the device. The hinged cover is secured by the long pin seen in the photo. A slot in the rope channel holds a knurled roller that moves upward during a fall, wedging the rope between the roller and the swinging cover. A hook in the bottom of the hinge pin forces the rope to run over the roller.
The left side of the LS-58 has a sticker with an up-pointing arrow labeled "UP" and the following information:
LAD-SAF®
ROPE GRAB
DBI/SALA ™
DB INDUSTRIES, INC.
RED WING, MN. 55066
SERIAL NUMBER
LS-R-76507
The right side has a virtual book stamped on it. It reads as follows:
UP MODEL No
LS-58
SAFETY NOTE
INSPECT ENTIRE SYSTEM
BEFORE EACH USE
DO NOT USE IF WEAR EXISTS
FOR USE ONLY WITH
4 FOOT MAX. LANYARD
5/8 DIA. SYNTHETIC ROPE
MINIMUM STRENGTHS
ROPE/LIFELINE: 5400 LBS.
TIE-OFF POINT: 5400 LBS.
APPROVALS
NYS. No 8860
CALIF. No. C-4450
ROPE SIZE GAGE
DO NOT USE IF ROLLER
CAN BE MOVED UPWARD O
PAST DOT WHEN
ROPE/LIFELINE IS IN PLACE
PATENT NO'S
US-3,876,036
CAN-1,030,732
The LS-58 is protected by U.S. Patent 3,876,036.
The LS-58 uses a sliding roller and a rope bending action to provide its fall stopping capability. The LS-58 could be used as an ascender, but its large size and top-mounted tie-in point would make this impractical. The roller idea might be used to make a more workable ascender, especially if it was spring-loaded. The rope bending contribution has been applied in some ascenders (e.g., the Hiebler), but leads to inefficiency due to the lost motion.
The braking action is assisted by the high tie-in point, which is the rod passing through the device at the upper left. Most of the side plate is nonfunctional, and could easily have been lightened by judicious drilling.
If the LS-58 were any smaller, there probably wouldn't be enough room to stamp all of the text on the right side. By the time you read all of this, your partner finished the job and you can go home.
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I acquired a used pair of LS-1441s on eBay in 2005.
The LS-1441 side plates are stamped from 1/8" (3.2-mm) stainless steel. Each plate has a diagonal slot cut in it, which is covered by another stainless steel stamping riveted in place. These pieces have small drain holes at their base. Three rivets and a welded pin connect and separate the two plates, holding them 18.9-mm apart. The top rivet supports a 22.4-mm hard plastic roller. The second rivet acts as a actuation lever stop and also supports one end of the lever spring. The third rivet provides an axle for the actuation lever. and the lever spring. This rivet is about 5.5-mm in diameter, but supports a 16-mm notched guide bushing that keeps the actuation lever from tilting sideways. One end of the axle is welded to the left side plate. Finally, a 9.5-mm diameter pin is welded between the two side plates near their base.
The rear of the side plates are bent to form slots for the rear hinge pin (left side) and quick release pin (right side). The rear piece is milled aluminum. It has a U-shaped groove mulled on the rope bearing surface and a small 9.5-mm hard plastic roller mounted at its base. A small slot near the rope channel house a small metal tab that is pinned loosely in place. This is an aid to help prevent mis-rigging. If the device is upside down, this tab should fall and keep one from closing the device.
The actuation lever is formed from two stainless steel stampings. These are bent so that they touch at the interior end, but separate at the exterior. An 11.2-mm rod welded between the two provides a tie-in point. The lever acts on a knurled roller that runs in the hidden slots in the two side plates. When one loads the lever, it forces the roller upward. The roller is free to move further, if necessary, since the lever action only pushes the roller half-way up the slot.
The left side of the LS-1441 is stamped with an arrow labeled "UP", "HAUT," "AUF," and "ALTO" and the following fine print message:
WARNING
INSPECT SYSTEM
BEFORE EACH USE.
PARTS MUST BE
FREE AND IN WORK-
ING ORDER. FAILURE
TO READ AND FOLLOW
ALL INSTRUCTIONS
AND MARKINGS
SUPPLIED WITH
THIS PRODUCT MAY
RESULT IN INJURY.
SEE OTHER SIDE9 93
The right side is stamped with 'ROPE DIAMETER 5/8",' "LS-1441," "NO. 9194A," and the following fine print messages:
WARNING
USE 5/8" (16MM)
DIA. SYNTHETIC
LIFELINE ONLY.
POLYPROPYLENE
ROPE IS NOT TO BE
USED. MAINTAIN
LIFELINE VERTICAL
AS POSSIBLE. DO
NOT USE ROPE OVER
SHARP EDGES.
SEE OTHER SIDE.
U.S. PAT. NO. 4657110
CAN. PAT. NO. 1241937
U.K> PAT. NO. CB2168102 B
DB INDUSTRIES, INC
RED WING. MN. 55066
The back of the device has a sticker that reads as follows (the first two lines are next to two arrows):
UP, HAUT
AUF, ALTODBI/SALA ™
SERIAL NO.
R45748
CAPACITY
310 LBS
(141 Kg)MEETS OSHA,
ANSI Z359.1
AND ANSI
A10.14-1991
WARNING
LIFELINE MUST
BE INDEPENDENT
OF PLATFORM
LIFT OR
SUPPORT LINES
The left side of the actuation lever is stamped, "MAXIMUM LANYARD 3 FT. (90CM)." The right side is stamped, "DO NOT OBSTRUCT LEVER MOTION."
The quick release pin is stamped, "AVK PUSH BLC5R495."
The LS-1441 is protected by U.S. Patent 4,657,110.
The roller appears to be identical to the roller in the LS-058, but it rides in a sloping slot and is lever-actuated. This may be a more reliable system, but a lack of volunteers delayed testing: I don't have enough expendable people to throw off of cliffs and buildings.
My second LS-1441 is serial number R45756, and is essentially identical.
These guys love to write a lot of $#¡Ý on their devices.
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