The studio hired Paul Byer to produce the infamous "Excalibur" saws for the film, for $3000 each. A total of three of the excalibur saws were made for the film. The following is what Paul shared about the 3 saws he built.
1) Fully functional motor with rotating sharp chain
2) Fully functional motor with non rotating sharp chain adhered in place
3) Fully functional motor with rotating chain that has teeth removed
The chainsaws used were all Stihl model 034. Both the Chainsaw in the first scene that Leatherface is seen in, where he attacks the trunk of the car, until the end of the movie the only saw he uses in an 034 Stihl. There are several different versions of the 034, and even though the details are small there is a correct one, and a couple that are not 100% accurate
Other sites have claimed that the saw used was an 066 magnum,. this is not true. I got my info direct from the man who built the saws for the film, not someone who is guessing. Another nail in the 066 rumors coffin, came in March of 2014 when I helped restore the last known excalibur known to exist. This saw is without doubt a model 034.
Baby Excaliburs were also made for the wrap party, and were given out at the first and only "Chainsaw awards". The cast and crew (and studio) thought that this film would be the start of annual releases in the films series, as Friday the 13th and A Nightmare on Elm Street were doing at the same time. These 'Baby" excaliburs were made of plastic, and no pictures are known to exist of what they looked like.
In December 2012 a screen used hero Excalibur saw was offered up on an auction site, the saw with the teeth removed from the chain. This is the first of the saws to have come out from hiding, and it is unknown if the other 2 are still out there. This saw was previously owned by an ex-New Line employee. The auction house estimated the saw would sell for between $2000 and $3000, the final winning bid for the saw was $11,000. After all auction fees and shipping, the total was close to $13,000
The Original Chrome Excalibur Chainsaw used in the trailer as it is today (unrestored)
In 1989, New Line Studios began working on the 3rd installment of the TCM series. On July 18th they shot the theatrical trailer for the film before any film footage was ever shot. It was rumored that a stunt double from part 2 was used to play Leatherface, not R.A. Mihailoff who was the actor who eventually played Leatherface (Junior) in the film. It is also rumored that Kane Hodder played Leatherface in the trailer. It was once believed it was Bob Elmore who did the stunt scenes (as well as most of the others) in part 2, but this is not true. At this point in my research I have yet to determine or confirm who actually played Leatherface in the teaser trailer, but we do know for sure it was not R.A. or Kane.
A company called Cimarron was hired to do the trailer, which was also the same company that did the trailer for John Boorman's "Excalibur". It was requested to be a shot-for-shot parody with the chromium Excalibur Saw reclaimed from the lady of the lake by Leatherface himself. The Saw created by Cimarron even has dual exhaust pipes on it. They made 2 of these Chromed out Chainsaws. One of them was gutted on the inside, and an electric motor was added to make the saw function, which was probably the saw used in the shot of it coming out of the water. The other saw was fully functional and was in the shot where Leatherface revs and turns to the camera. It happens to be (not sure by coincidence) the same exact make and model of saw that was used in the film as well.. a Stihl 034. The "Lady in the Lake", was actually not even a lady. A male stunt diver was used because the lake in Pasadena the trailer was shot on, was so shallow the diver had to lay on the bottom and could only get part of the saw under the water. Thus the saw was taken apart and the first shot is only half of the saw. They cut, and filmed the rest after the saw was reassembled.
- An alternate Cimarron idea used the chainsaw as the sword in the stone, with the hands of Jason Voorhees and Freddy Krueger attempting -and failing- to remove it. (just as cool in my opinion, wish they would of at least shot it).