LocomotiveHorns.info - SuperTyfon   
 
History

Leslie SuperTyfon horns were the replacement of the Tyfon horns. In particular, they were to replace the failed Tyfon Chime Tone line of multi-note horns. Interestingly, Leslie called the earliest SuperTyfon horns Chime Tone horns as well, which very quickly evolved to "chime whistles". Note that Leslie has always called - and continues to call - their horns "whistles". The SuperTyfons were actually a product they licensed from Kockums of Sweden, who provided the very first prototypes and chords to Leslie. These horns are easier to maintain, in part due to interchangeable parts among all SuperTyfon models. Unlike the AirChime M series horns, the power chambers are interchangeable among any bell on any SuperTyfon horn, and unlike the early Tyfon models, the back cap does not screw on, but rather bolts on for easier maintenance; in typical service, no adjustments are ever needed.

The SuperTyfon line was introduced in 1951 with the S3J and S5D. These horns sounded the same chords as the M3 and M5 offered by AirChime at the time (A-major triad and A-major 7th). Just after these were announced, Leslie added the S3E and S5A to their offerings. Then in late 1952, not even two years after the SuperTyfon line was introduced, all of these models were dropped in favor of the S3L and S5T, changing Leslie's style forever. It is believed that this was due to pressure from AirChime and Nathan to prevent Leslie from copying "their" chords. Leslie took this opportunity to market their horns with the theory that a slightly off-key, less-pleasing chord, will work better as a warning device, which is in part how the 25 bell (as opposed to the 247 bell), and the S-3L and S-5T, came into being. Since then, other offerings have joined the SuperTyfon line, but the original four horns from 1951 have never been reintroduced. SuperTyfon horns have been a mainstay of many railroads since their introduction over 60 years ago, and they have changed very little over that time. Though no railroads are known to have purchased SuperTyfon horns in the past couple of years, Leslie Controls still offers these products.


Designations

The designations for SuperTyfon horns can get quite tricky, though thankfully not as tricky as Tyfon horns, since the designations have not changed over time. Designations start with the letter "S", supposedly standing for "SuperTyfon". Next is a dash followed by the number of bells in the chime (2, 3, 4, or 5), directly followed by a letter corresponding to the chord the horn produces. This simple designation represents a factory-configured, variable orifice, all-bells-forward configuration of the given horn. For example, an S-5T represents a 5-chime SuperTyfon on the standard 5-chime manifold, variable orifices to each bell, all-bells-forward, playing the T chord, and using the factory-standard arrangement of bells on the manifold. By adding various prefixes and postfixes, many other configurations can also be classified.

The first prefix is the letter "R", which designates a horn with the newer spike-back chambers. If this is the case, our S-5T is now considered an RS-5T. The other "prefixes" are actually inserted between the leading S and the dash, and are as follows:

  • "L" - low-profile 3-chime or 5-chime manifold
  • "U" - very low profile 3-chime manifold ("U" for Universal) - looks like a 2-chime manifold with a third port slightly lower, off to one side
  • "M" - used exclusively on single-bell manifolds, to denote when a #1 orifice dowel is used ("M" for Maximum)
Our RS-5T can be classified as an RSL-5T if it has been set up on the low-profile 5-chime manifold (though it is believed the low manifold was only used for the SL-4T, and never an S-5T). Next there are numerous postfixes that can be tacked onto the end of the designation, and they are as follows:
  • "J" - narrow 3-chime manifold used by the S-3J, when applied to a horn other than the S-3J (cannot be used with "L" or "U" prefix)
  • "F" - full orifices
  • "R" - one bell reversed, sometimes also used with the 31 and 55 bells both reversed
  • "RR" - two or more bells reversed, usually the 44 and 55 bells
  • "O" - normal arrangement of bells on the manifold from left to right has been reversed or changed
  • "X" - several different meanings - in the case of the SL-4T, "experimental" - in the case of the S-2M, optional secondary air inlet - other uses unknown
Thus, if our RSL-5T has the 44 and 55 bells reversed, and has the bell order changed from the factory-specified configuration, it is now considered an RSL-5TRRO. Another combination is the S-3BJ, which is the 3-note SuperTyfon tuned to the "B" chord, variable orifices, and set up on the J style manifold. Yet another is the RS3-KR (popular with Burlington Northern), which is the 3-note SuperTyfon tuned to the "K" chord with RS-style power chambers, variable orifices, one bell reversed, and set up using the standard 3-chime manifold. Still another combination, used exclusively on Amtrak, is the SL-4T. This horn is the 4-note T chord mounted on the low-profile 5-chime manifold (no four-chime manifold existed), with variable orifices.

Last, there are special designations for SuperTyfons using only one size bell. Single-note horns are based as an S-XX, where XX is the number of the bell. Therefore, an RSM-25 is a single-note horn using the 25 bell, #1 orifice dowel, and a newer RS-style power chamber. Leslie also offered two-bell and four-bell horns with duplicate bells, one facing each direction (or one in each of four directions). These would be classified as an S-XX-2 or S-XX-4, respectively, where XX is the number of the bell used. An S-44-2 would be a pair of 44 bells on a 2-chime manifold, one facing each direction. This combination - and the four-way combination - was used as an industrial warning horn, not a railroad horn.

Following is a table of all known chords available for multiple-note SuperTyfon horns, past and present, along with the bells used to produce them and the notes played. Interesting is the S-2D, marketed for railroad use, using two 37 bells, supposedly facing the same direction unless ordered as an S-2DR. I'm not aware of any installations of this model on a locomotive, though. Also, since the 25 bell plays C, and not B as advertised, the table reflects the note heard, not advertised; the only horns that play a "B" are those with a 247 bell.

Chord Bells Used Chord Notes
S-2A 25, 31 minor third C,  D#
S-2B 31, 37 minor third D#, F#
S-2D 37, 37 n/a F#
S-2G* 31, 55 n/a D#, C#
S-2H* 37, 48 major third F#, A#
S-2M 31, 44 tritone D#, A 
S-3B 37, 44, 55 F# minor F#, A,  C#
S-3C 25, 37, 55 n/a C,  F#, C#
S-3E** 247, 277, 370 n/a B,  C#, F#
S-3J** 277, 330, 440 A major triad C#, E,  A 
S-3K 31, 37, 48 D# minor D#, F#, A#
S-3L 25, 31, 44 n/a C,  D#, A 
S-3P 25, 37, 55 n/a C,  F#, C#
S-3T unknown unknown unknown
S-4T 31, 37, 48, 55 D# minor 7th D#, F#, A#, C#
S-5A** 247, 277, 311, 370, 440 B major 7th B,  C#, D#, F#, A 
S-5D** 277, 330, 392, 440, 554 A major 6th C#, E,  G,  A,  C#
S-5T 25, 31, 37, 44, 55 C dim with
flattened 9th
C,  D#, F#, A,  C#
  * the S-2G and S-2H combine to create an S-4T
 ** only offered in the first year of production
    - also, early S-3Es played B, C#, F, and early S-5As
    played B, C#, D#, F, A, identical chords to the
    A-125-3E and A-125-5A

kaspriske_030614_3.jpg Ed Kaspriske brought along his S-3BJ to Oak Ridge 2003 - note the J-style manifold on this horn
s5d_030614_5.jpg an original S-5D - Ken Kanne and Ken Lanovich did an excellent job restoring this horn to it's former glory
s5t_031231_2.jpg here is an S-5TFRRO that I obtained for restoration a few years back
sl4t_weart_1.jpg a close-up of one of Ray Weart's ex-Amtrak SL-4TXs
sl4t_weart_2.jpg two of Ray's SL-4TXs, one with Amtrak-installed snow cones
sl4t_manifold_kanne.jpg the SL-4T manifold on its own - this is actually a reproduction manifold, only distinguishable by the stamp indicating as much on the bottom - note the "LP" indicating "low profile" as found on the backs of these manifolds (© Ken Kanne, used with permission)
s25_weiler_1.wav an S-25 on one of Blue Mountain and Readings RDCs in active service - notice the squealing which was common on many S-style power chambers
s2m_011117_1.wav my S-2M - this horn was common on many of NYC's E-8s
s3j_030614_1.wav the S-3J is a rare find, and pretty-sounding, too
brw1853_011125_2.wav the S-3J's replacement, the S-3L - even the dog doesn't think it's very musical!
ns_010915_1.wav this RS-3L was recorded about a mile away from Conrail's main (now Norfolk Southern) in Three Bridges, NJ
brw1853_030104_1.wav here is my S-3K while in active service, recorded close to a mile in front of the train
s4t_011218_2.wav I converted my S-5T into an S-4T temporarily, with good results
s5a_050910_01.wav one of my S5's converted temporarily into an S-5A, being static blown in Altoona
s5a_050910_02.wav the same S-5A "replica", during one of the late night runbys - shims were used to achieve the 247 and 277 notes
s5d_030614_4.wav here is an original S-5D, tuned to A Major 7th, not A Major 6th as most reproductions are
rs5t_030614_2.wav an RS-5T blown at Oak Ridge - it's easy to hear why many people consider this the greatest of air horns


Power Chamber Construction

Bronze Chambers

The primary changes to the SuperTyfon line over the years have been with the power chambers. When they were first introduced in 1951, the power chambers were cast bronze, with two-piece diaphragms consisting of a stainless steel disc and ring. The back cap also has a second disk permanently riveted in place, called the spreader plate. Because of this disk, the back cap has a slightly domed appearance. The general form of these chambers is round, with six tabs protruding around the circumference, which are used to bolt the back cap to the rest of the power chamber. Power chambers of this style are referred to as "tab-back" power chambers.

The bronze chambers went through several changes before they were dropped in 1956 for aluminum chambers. The earliest bronze chambers used a short, pressed-in orifice dowel to meter airflow to each chamber. They also had studs threaded into the heads, which were used to attach to the bells, as well as set pins in the associated bells (since there is no orifice dowel) such that the bell could only go on one way. After about a year, in early 1952, the studs, set pins, and orifices disappeared, replaced by bolts that feed in through the bells and thread into the power chamber, and longer orifices dowels pressed into the bells, respectively (set pins permanently eliminated since the new dowels doubled in the same role as the old set pins). Also at this time, "Swedish Make" (not "Made") started to appear stamped into the inner face of the power chamber (the face that butts up to the bell). These represent the ealiest of the bronze chambers that are interchangeable with todays bells (the earliest chambers do not fit todays' bells because of the pressed-in orifices). It is believed that the "Swedish Make" stamping only lasted a year or two, though they have shown up on horns as late as 1956, (likely swap-outs or old stock). The only other significant design change occurred in early 1955, after "Swedish Make" stamps stopped appearing. Up to this point, the power chamber nozzles were machined separately, and then threaded into the head (some may have been pressed as well - it is unclear). In 1955, a switch was made to one-piece heads with integral nozzles, machined along with the rest of the head. These "one-piece" bronze heads were the most common and were the norm until bronze heads were dropped in late 1956, or possibly very early 1957.

On a side note, Leslie applied seal wire to the six back cap bolts, and the three bolts attaching the bell to the power chamber, on nearly all horns produced with bronze chambers. This was accomplished using bolts with holes drilled through the heads, just for this purpose. No aluminum power chambers, or horns with aluminum chambers, have ever been found with seal wire, or even the bolts drilled to use seal wire.

Aluminum Tabbed Chambers

In 1957 the power chamber construction was switched from bronze to aluminum. The aluminum chambers are more prone to wear, but are cheaper to manufacture and weigh a lot less than their bronze counterparts. There were no real changes in the production of the aluminum tab-backed chambers, save one. All the bronze chambers bolted together with six bolts that passed through the back cap and threaded directly into holes in the main part of the head. The very first aluminum chambers were set up this way, but were changed within the first year of production to instead have through bolts and nuts. My assumption would be that the corrosion between the aluminum heads and steel bolts would make it very difficult to remove the bolts over time if threaded in directly, hence the change, though I cannot verify this. Tabbed chamber construction continued up through late 1965.

Round-Back Chambers

Starting in early 1966 (or possibly very late 1965), new power chambers starting appearing that were completely round. (However, tabbed chambers - old stock - still showed up on new horns as late as 1968.) The gaps beteen the tabs of earlier power chambers were filled in to achieve this style. This strengthened the construction, since it was found that the tabs on older chambers tended to snap off if hit the wrong way, such as by a tree limb at the wrong time. The change was external only; these chambers retained the same diaphragm construction inside, including the domed back cap with diffuser plate. Because of the round appearance, and the domed back cap, these newer chambers are referred to as "dome-back" or "round-back" power chambers, even though the tab-back chambers had a domed back. Round-back chambers continued to be the norm until about 1977. Over the years, a few different casting marks could be found on round-back power chambers. The most common was a "5" that was cast in the back cap. This started to appear on chambers between 1970 and 1972, and continued through the end of production.

Spike-Back RS Chambers

Over time, it was found that SuperTyfon power chambers were prone to fail when dirt, grease, and other contaminants were introduced into the air line. While strainers can help reduce this, the railroad atmosphere is guaranteed to be dirty, and so it is impossible to keep all contaminants out. Likewise, the Leslie domed power chamber had gone past its patent protection of 20 years by the early 1970's (and Prime Manufacturing started to produce horns using the Kockums/Leslie design). To help reduce the chance of failure, and to produce a newer, better, patentable chamber, Leslie designed the "RS" power chamber, or "improved" chamber as Leslie sometimes referred to it.

Released in 1977, these chambers are circular, like the round-back chambers, and are interchangable with any of the older chambers except the very first bronze heads. Externally they are different in that the back is flat with a large spike protruding from the lower rear of the back cap. The heads are also built a bit lighter, with a little less material. The purpose of this spike on the back cap is described in the maintenance section of this site; suffice to say here is that it helps provide a restoring force for the diaphragm after initial deflection. Because of the spike on the back cap, the RS power chambers are sometimes referred to as "spike-back" power chambers. Internally, the diaphragm is different; there is now just a single stainless disk, with a silicone cushion ring that seats in the back cap to seal the outer rim of the diaphragm. The silicone ring helps prevents wear to the outer edges of the diaphragm as well. In addition, the face where the bell butts up to the chamber has been hollowed out, with three support ribs remaining. To ensure a good seal between the chamber and the bell, small compressable ring gaskets are used between the two; without them, the bells tend to squeal, overblow, or just not sound. Spike-back power chambers are indeed much more reliable than their dome-back and tab-back counterparts.

The spike-back power chambers have three different styles. The earliest chambers have "Patent Pending" cast into the back cap, along with "Parsippany, NJ". Newer chambers have the patent number instead of "Patent Pending". The newest runs (since Leslie moved to Tampa) have "Tampa, FL" cast into the back caps instead of Parsippany (the patent numbers remain). Also of note is that the older RS heads have a nozzle that is a couple millimeters wider than the newer, Tampa heads. The Tampa heads are more prone to fouling, squealing, and other damage from dirt and other contaiminants in the air line due to the narrow nozzle. It is also said that the Tampa heads have a more harsh sound than the older Parsippany heads, though this could be due to less wear as they haven't been in service as long - it is unclear and highly subjective.

s3j_chamber_ray_weart.jpg earliest bronze power chamber design - note pressed in orifice, pressed/threaded nozzle, and studs to attach to the bell (© Ray Weart, used with permission)
powerchamber_040215_1.jpg the insides of a tab-back power chamber, which are identical to those of a dome-back power chamber
powerchamber_040215_2.jpg a tab-back and dome-back chamber side-by-side
rs5trro_oakridge.jpg an RS-5TRRO at Oak Ridge 2009 - note the spiked protrusions from the back caps of the RS heads and the squared-off air passages
s3l_030614_2.wav here is an S-3L with tab-back power chambers
rs3l_020622_1.wav compare that to this sound clip of an S-3L with RS-style, spike-back power chambers


Bell Construction

Bells have also changed slightly over time. Unlike AirChime bells, Leslie bells are not numbered 1, 2, 3, etc. Instead they are numbered based upon the frequency of the sound they produce in Hertz. For instance, a 247 bell blows 247Hz, or B below middle C. Three-digit bell numbers were used in the first two years of production only, and the number was cast on a raised rectangle at the base of the left side of the bell. When the S-5D, S-3J, S-5A, and S-3E were discontinued in late 1952, bell numbers were shortened to two-digits, dropping the last digit. For instance, the 554 bell is now just a 55 bell. Also at this time, the 247 bell was replaced by the 25 bell, which plays close to a C instead of the 247's B, and the 277, 330, and 392 bells were completely dropped from Leslies offerings. All the other bells were retained and shortened to two-digit numbers. Within the first couple of months of two-digit bell production, the numbers were moved to the right side of the bell instead of the left, and at the same time, the "Leslie" or "Leslie SuperTyfon" lettering started to be cast into the left side of the bell. Of note, the bottom of the 25 bell, unlike the 247, appears to be "shaved off". This is intended, as the bells are cast like this, not shaved, or filed, after casting.

When the SuperTyfon line was first released, Leslie did not have the capacity to cast the large 247, 277, 311, and 370 bells as one piece. Instead, these bells were cast as two pieces and then welded together. Welded bells have a unique ring halfway up the throat where the two bell pieces come together - the weld is not ground down fully, just enough to remove any rough edges. The 370 bell was welded only for a short time. (Oddly, the two-piece 370 bells played F, and not F#.) However, all 247, 277, and 311 bells were welded bells, through to the end of production or 2-digit conversion. After conversion to 2-digit bell numbers, welded 25 and 31 bells continued for several years; welded 25 bells were produced through very early 1956, and welded 31 bells through mid 1956 (though welded 31s showed up on new horns as late as 1958).

The last major difference in the bell construction involves the bell number. Over time, each bell was recast, with the number appearing in a raised circle instead of a raised rectangle. Likewise, the "Leslie" and "SuperTyfon" logos were originally cast as two separate raised rectangular blocks. These were also consolidated to a single, rounded-end block around the same time as the raised circle change. The last bell to be recast is supposedly the 37 bell, being recast as late as the early 1970s by some accounts, though the actual dates are unknown. Also of note is that earliest 55 bells had the 55 cast in a raised rectangle, though this ended within about a year, in early 1953. Until the final casting using a raised circle, the 55 is just cast on the bell surface, without any raised block underneath. Below is a table listing what are believed to be the relative timeframes for each bell, based on the number block style.

Bell Years Number Style
25 through early 1956
early 1956 and up
raised rectangle
raised circle
31 through mid 1956
mid 1956 and up
raised rectangle
raised circle
37 through late 1960s
late 1960s and up
raised rectangle
raised circle
44 through mid 1960s
mid 1960s and up
raised rectangle
raised circle
48 through mid 1960s
mid 1960s and up
raised rectangle
raised circle
55 through early 1953
1953 through late 1960s
late 1960s and up
raised rectangle
not raised
raised circle
NOTE: most dates are approximate, not 100% acccurate
NOTE: in many cases, the older style bell continued
      to appear on new horns a year or two after
      the new style started to be cast (old stock)

There are many minor changes that have occurred with the bells throughout the lifetime of the SuperTyfon horn. One of the earlier changes is the use of an O-ring on very early bells, such as the 440 bell. The O-ring appeared around the outside of the bell where it sits in the manifold, about mid-way between the flange and where the bell meets the power chamber (see pic below). This was done because the early manifolds had air passageways that opened up into the slot where the bell passes through the manifold. The O-ring helped to seal the air at this location. Another minor change was stamping of the registered trademark symbol ®, typically near the "SuperTyfon" logo. This practice continued on bells through about 1957. Manifolds, as noted below, were stamped much later. Newer 44 bells also had a unique feature, which started appearing regularly in the mid 1980s (some say the first were as early as 1970). The letters "BAF" were cast next to the "44" on a raised rectangle or diamond on many 44 bells until very recently. BAF represents the Boose Aluminum Foundry, through which Leslie produced many of their 44 bells (and possibly their other bells as well). Leslie was known for farming out much, if not all, of its foundry work. There are other minor differences, and bells with anomolies such as no bell number cast, very early 330 bells with the number upside-down, etc., though these are too numerous and isolated to list.

early_440.jpg very early 440 bell with O-ring grooves and one O-ring installed (© Ken Kanne, used with permission)
early_25bell.jpg an early 25 bell showing the Leslie and SuperTyfon logos in one rounded block, with a ® stamp
early_31bell.jpg an early 31 bell showing the Leslie and SuperTyfon logos in separate square blocks, with a ® stamp
early_s3l_1.jpg a very early S-3L, from 1952, or possibly 1953 - note the lack of the Leslie SuperTyfon logo on the bells
early_s3l_2.jpg the same early S-3L with bell numbers and welded bells visible
s2m_weart_1.jpg Ray Weart's old S-2M with bronze power chambers and two-piece 31 bell - note the numbers are in rectangles, not circles
s5t_weart_1.jpg Ray's 1952 S-5T - notice some of the bells have numbers on opposite sides as other bells


Orifice Dowels and Variable Orifice Horns

The earliest bronze power chambers from Kockums had no way to meter - or restrict - the air flow from the manifold into the power chamber, resulting in a horn that is louder than desired and which wears out faster. Before releasing the product under their name, Leslie decided to restrict the airflow by inserting a short, hollow aluminum dowel into the orifice on the power chamber. Since less air flows through the smaller dowel than the original hole in the power chamber, the horn now wears slower and isn't as harsh. Within a year or two of this, Leslie realized it may be simpler to press the dowel into the bell instead of the power chamber. Obviously, the dowel would need to extend the full length from the bell to the power chamber orifice, and would need to have a hole drilled in the proper place to allow air to enter from the air passages in the manifold. However, using this construction, it is simple to change the amount of air received at any one power chamber/bell - simply drill a different-sized hole. Leslie can also use a single power chamber part number for all horns, and instead catalog bells with different orifices (which wasn't an issue since they already catalogued many different bells).

A horn with different size holes in the dowel for each bell, called the "orifice dowel" or "orifice pin", will typically sound more balanced when heard up close. This is due to the human ear perceiving higher-pitched sounds as louder than lower pitched sounds of the same volume when heard up close. Thus, these "variable orifice" horns started to be catalogued by Leslie as an option for nearly every horn they produced. Today, each bell is offered in several different orifice sizes. In addition, since the dowels are only lightly pressed into the bells, it is simple to mix and match dowels, or create your own dowels and orifice combinations, by swapping dowel pins. Decent pliers are usually all that is needed to remove a dowel.

There are five different orifice sizes, ranging from #1 - the largest and therefore the loudest - up through #5 - the smallest. A #1 orifice dowel has a hole drilled with a 0.172-inch diameter. A #2 uses a 0.125-inch hole, a #3 a 0.109-inch hole, a #4 a 0.095-inch hole, and a #5 a 0.080-inch hole. Leslie scribes the number above the hole to make it easier to distinguish which orifice size is drilled. The #1 orifice is reserved for use on industrial warnings and other horns used only infrequently due to the wear it causes on the power chamber, and due to the large volume of sound; railroad horns will never have a #1 orifice dowel. Rather, Leslie offers "full orifice" horns that used the #2 dowel on all bells, as well as "variable orifice" horns that use dowels from #2 and up on each bell. A table with the various orifice sizes for common horns, along with hole diameter in inches, as received from Leslie, is shown below.

Horn Model Bells Used Dowels Used
S-2M* 31
44
2 / 0.125
3 / 0.109
S-2A 25
31
2 / 0.125
3 / 0.109
S-2D 37
37
2 / 0.125
2 / 0.125
S-2B 31
37
2 / 0.125
3 / 0.109
S-3B** 37
44
55
2 / 0.125
3 / 0.109
3 / 0.109
S-3L 25
31
44
2 / 0.125
3 / 0.109
3 / 0.109
S-3K 31
37
48
2 / 0.125
3 / 0.109
3 / 0.109
S-3P 25
37
55
2 / 0.125
4 / 0.095
5 / 0.080
S-4T 31
37
48
55
3 / 0.109
4 / 0.095
5 / 0.080
5 / 0.080
S-5T 25
31
37
44
55
2 / 0.125
3 / 0.109
4 / 0.095
5 / 0.080
5 / 0.080
  * represents the standard variable
    orifice setup for most 2-note horns 
 ** represents the standard variable
    orifice setup for most 3-note horns 


Manifolds

Even the manifolds of a SuperTyfon tell a story! The very first manifolds were designed by Kockums, and were not the strongest of manifolds. For instance, the 5-chime and high-profile 3-chime manifolds did not have any support ribbing. As a result, it was much easier for bells to snap off if hitting something unexpected like a tree limb. Within the first year, Leslie strengthened their manifolds, adding support ribbing, even to the early "flat" three-chime manifold. Interestingly enough, the early high-profile "J" style manifold was never upgraded, though the now common low- and high-profile manifolds were built starting around 1953 to remedy that situation, as well.

There were many other, more minor, changes in the manifolds throughout the first few years of production. Originally the identification tag could be found on the back left of the manifold, though the location changed to the back right sometime in the middle of 1953. Early tags, through mid 1953, were etched with the horn model, not stamped, as well (for those where the tags were not pressed with the model). There were other changes in the tags over the years, as visible in the diagram linked below. Also of note is that early tags were not painted black, as far as any collectors can tell. In mid 1953, one other change occurred on the manifolds - the main air passageway casting changed from a more rounded casting to a rectangular casting, which has stayed ever since. Starting in 1954, manifolds started to appear with pipe plugs in the ends (where the primary air passage was drilled out). It is well accepted that this was an option, either by the railroad or those constructing the manifold, as tapped and plugged vs. welded ends are inconsistent from this point on. The last significant change occurred in late 1955 or early 1956. Manifolds overall were somewhat less heavy after this time. The simplest way to tell is the bottom flange, which originally was a little over 1/2-inch thick. From that point on, the flange was a little under 3/8-inch thick. Interestingly enough, sometime after moving the company to Tampa, the thicker manifolds started appearing again.

Of primary importance to help identify a horn is the date stamp, which was applied through 1976. The date stamp will be a 2-digit number, representing the last two digits of the year the horn was sold, and is found on the bottom-rear of the manifold, on the flange where the horn is bolted down to the locomotive. However, only complete horns were date stamped; replacement manifolds do not have dates stamped on them. Also while all manifolds from the 50s and 60s were stamped, it seems that stamping was inconsistent in the mid 1970s. Like early bells, the registered trademark symbol ® was stamped into nearly all manifolds up through 1969 as well. By this time, all manifolds were being cast with the ® symbol, and so stamping was no longer necessary. One of the later changes on manifolds is the addition of bolt-relief cutouts on the mounting flange, making it easier to tighten up the mounting bolts. These cutouts started appearing around 1980.

leslie_r-512_p3.pdf a very early Leslie marketing pamphlet page, showing the original four models, as well as the very early Kockums-designed manifolds
s5d_030614_1.jpg on the S-5D and S-5A, a narrower, taller manifold was used - this is the imporved design with additional trusses and support webbing
s5d_manifold.jpg again, the improved manifold for the S-5D - note the rounded, not squared, air passages (© Ken Kanne, used with permission)
early_s3l_3.jpg the same early S-3L as above - note the improved low-profile manifold intended for the S-3E
s3bj_oakridge.jpg a mid-to-late 1950's S-3BJ at Oak Ridge 2009 - note the older bells and J-style manifold
leslie-tags.gif a graphical history of the various Leslie manifold tags (© 2008-2011 Philip Martin, used with permission)



Last modified Oct 30, 2011
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