Can't remember the name of these, Osa's I think. They were working in the late 80's. Now the poplar trees are growing up through them.
Interesting to see the 670 fb again. The swedish manufacturer ÖSA (Östbergs Smidjesfabrik AB = Ö Blacksmith Inc - and btw the Ö = Ø and is pronounced like the "i" in "first") was early and leading in developing the hydrostatic transmissions on wheeled forest machines. Their first production models was in fact the 270 leveling chassi (the chassis for the 670 fb seen on the pictures) and maybe WIW adopted ÖSA's ideas for their FB. The machine was clearly futuristic and clearly utilized close to ALL opportunities the hydraulics could give. It also clearly was an answer to ÖSA's recently ended relationship with Volvo Bolinder Munktel, which at that time, besides Kockum, was belong the biggest manufacturers of spesialized forest machines in the world (Volvo BM would never take the step to hydrostatic driven machines, and sold later their forest machine division to Valmet)
Later in the 70's ÖSA intoduced the 260 forwarder, two grip harvester, clambunk skidder etc, this was the first functional all hydrostatic driven forwarder. Many of these machines are still in use.
In Sweden and Scandinavia the 670 were used together with the Kockum or Volvo Logmas's (boom delimbing machines that was the predecessor to today's american stroke delimers) or they worked with early processors as the Volvo 985. Since the mainstream realtively fast went to two grip harvesting machines (they both falled, delimbed and CTL) these machines only had a relatively shortlived era from the late 70's until mid 80's.
Because of the relatively complexity of the hydraulics, and the usefulness, only a few manufacturers have produced leveling wheeled harvesters. This is ÖSA, Skogsjan => CAT => Ecolog and Konrad Forsttechnik in Austria.
ÖSA was later, about 1989, obtained by the Finish corporation Rauma Repola and FMG (Forestry Machinery Group) was formed which also included the forest machine division of Kockum and the Finish forest machine producer LOKOMO. Shortly after also Bruun Systems of smaller forwarder and harvesters was included in FMG. In fact it seems LOKOMO had the greatest influence on todays Timberjack and John Deere machines, but most of the basics came from the pioner ÖSA.
For those interested in this history the book "En smedjas förvandling" aka the development of a blacksmith is highly recomended, I think FMG felt so international at that time they even published an english version. Try contacting John Deere Forestry in Sweden, they may still have a stock of it.
Around 1994 FMG bought the Canadian skidder producer Timberjack and also changed the brand name but not the colour of the machines. An internal evaluation at FMG/Timberjack came to that the green colour used by ÖSA first in the early 80's was more environmentally friendly than the orange of Timberjack. Later on TJ was bought by John Deere Corp and they only needed a slightly change of colours.
Here's some interesting links:
http://app.elmia.se/classic/files/osa270basmaskin1973.pdf
http://app.elmia.se/classic/files/osa670fäll1977.pdf
http://app.elmia.se/classic/files/osa705260deng1976.pdf
http://app.elmia.se/classic/files/volvobm985processor1975.pdf
http://app.elmia.se/classic/files/volvobm971skot1972.pdf
http://app.elmia.se/classic/files/volvobm995falllagg1976.pdf
more files at
http://www.elmia.se/en/skogselmia/For-fair-visitors/Elmia-Classics/