Everybody knows the story of gasoline chainsaws. Almost nobody knows the story of diesel chainsaws. For a brief stretch of the mid-20th century, a handful of manufacturers experimented with diesel and semi-diesel power, producing some of the rarest and strangest saws ever built.
Heavy, unconventional, and completely unlike the two-stroke gas saws that came to dominate the industry, these machines represent one of the most unusual dead ends in chainsaw history. This article rounds up the seven (or eight) known diesel chainsaw models and the story behind each one.
Most of the images shared here come from chainsawcollectors.se, an incredible chainsaw resource forum that everybody should sign up to and explore!
1. Comet A
- 1949 — Comet A
- Maker: Norsk Sagbladd Fabrikk
- Country: Oslo, Norway
The Comet A was the original Comet and the saw that started the whole diesel chainsaw story. Designed by Rasmus Wiig in Norway, it used the early spring-door rope pulley starter and laid down the basic formula the later Comet models would refine. It was never built in huge numbers, but it matters because it appears to have been both the first Comet and the first diesel chainsaw to reach production.
2. Comet B
- 1950–1953 — Comet B
- Maker: Comet / Como M. T. Bjerke
- Country: Stockholm, Sweden
The Comet B was the Swedish-built second version of the Comet diesel chainsaw, produced after Rasmus Wiig moved the project from Norway to Sweden and had it built by Como M. T. Bjerke in Stockholm. It’s the model most collectors picture when they think of a Comet, and it helped carry the design further than the original Norwegian saw ever did.
Production totals are still debated. Acres cites roughly 1,000 saws built between 1950 and 1953, while a ChainsawCollectors post appears to put the number closer to 3,000, so it’s probably safest to say that surviving estimates vary.
3. Comet S
- 1953–1954 — Comet S
- Maker: Comet / Como M. T. Bjerke
- Country: Sweden
The Comet S was the final version of the Comet diesel chainsaw and is best known for its Magnapull automatic rewind starter. That feature set it apart from the earlier Comet models, which used a more basic starter arrangement, and marked the last major update before the Comet design evolved into the Jonsereds diesel saws. In practical terms, the rewind unit is the easiest way to tell a Comet S from an earlier Comet A or B.
4. Jonsereds Raket P
- 1954 — Jonsereds Raket P
- Maker: Jonsereds, in cooperation with Como M. T. Bjerke
- Country: Sweden
The Jonsereds Raket P was the first diesel saw to wear the Jonsereds name and the bridge between the Comet line and the later XA models. It came right as Jonsereds took a bigger role in the project, carrying the diesel concept into its next phase without completely breaking from the Comet design that came before it.
Exact production totals are still a little murky, but collector Magnus has put the run at roughly 360 saws, which would make the Raket P one of the rarest links in the whole diesel chainsaw lineage. Collectors state the P was a pre-series, transitional, or limited-run model rather than the first full commercial market release.
5. Jonsereds Raket XA
- 1954 onward — Jonsereds Raket XA
- Maker: Jonsereds Fabrikers AB
- Country: Sweden
The XA was the first Jonsereds diesel actually sold on the market. It used the propane-heated hot-bulb system, and Acres notes the odd detail that the chain looks backward when the saw is upright because the saw was intended to be operated inverted once started. Estimated XA-family production is around 2,000 total, though that figure is presented as approximate.
6. Jonsereds Raket XA-19
- mid-1950s — Jonsereds Raket XA-19
- Maker: Jonsereds Fabrikers AB
- Country: Sweden
The Jonsereds Raket XA-19 was a rarer offshoot of the XA and one of the more obscure models in the diesel Raket line. At a glance it looks close to the standard XA, but collectors usually point to details like the squarer-edged fuel tank as the easiest way to tell it apart. That makes the XA-19 less of a full redesign and more of a small but distinct variation — the kind of model that matters a lot once you get deep into Comet and Jonsereds history.
7. Jonsereds XC
- circa 1955 — Jonsereds XC
- Maker: Jonsereds Fabrikers AB
- Country: Sweden
The Jonsereds XC was one of the strangest and rarest saws in the whole diesel chainsaw lineage. It replaced the earlier propane-heated bulb with an electrically heated glow plug and used a handlebar-mounted battery box with two D cells, giving it a noticeably different starting system from the other diesel Rakets. With production thought to be under 100 units and collectors often describing it as a U.S.-test or U.S.-bound model, the XC feels less like a mainstream production saw and more like a last, fascinating attempt to push the diesel idea a little further.
Bonus: Comet M
The Comet M appears to have been a rare semi-diesel variant in the Swedish Comet family and one of the least documented saws in the whole diesel chainsaw lineage.
Collector references treat it as a real Comet model (while calling it a “Ghost Saw”) and place it in the same hot-bulb family that eventually led to the Jonsereds XA diesels, but hard factory documentation is thin. That makes the M fascinating for collectors: not because it is well understood, but because it sits right in the hazy space between established production history and obscure variant lore.
