851 tractor, two versions?

[Jan]

While I was trying to get the digital versions of the instructionbooks of the sets I own, I found out that there are in fact two instructionbooks for the 851.

I own the instructions that fold out as a poster, with a complete 1:1 blueprint of the tractor, really sweet .

The second set of instructions I found on brickfactory and come as a traditional booklet. While I was browsing through this book, I not only found out that the build is in a different order, but there are some designchanges made that make the model more sturdy and playable (this model relies for it's playability highly on brick to brick connections).

There is in fact a sheet at the end of that scanned instruction booklet that let you convert the "old" version of the 851 lifting system into a "new" version, The thresher gets an extra part aswell to make it more sturdy (not shown on that extra folder).

Does anyone know about these two sets, and how I should see this in time?

Have changes in building technique and instructions been made before in what appears to be the same sets?

I guess, I got the set as a present somewhere in 1981, while peeron is showing 1977 as the release date.

I am just curious

Edited August 1, 2011 by Jan

[DLuders]

On the Blakbird's Technicopedia listing for the 851/952 Farm Tractor set, at the bottom it says "As long as the model is right side up, the push-pull linkage is always in compression so it tends to stay together. If the model is inverted, this is in tension and can pop apart.

If the thresher is lowered too far, the 40 tooth gear will fall under the PTO and jam. There are wheels on the thresher to make it level and prevent this from happening.

The original mechanism (pictured) had a weak spot at the aft end of the connector link. Only the friction on the studs kept this together, so it tended to come apart often. In 1978, LEGO® changed the design to have a vertical 1x4 beam at this location to hold things together. This resulted in a slightly different parts list and count for this set."

[Jan]

Thanks a lot for your quick reply DLuders,

So the only strange thing is that although I have got it as a present in 1981, it seems to be the original version prior to the 1978 re-release.

One thing I also want to mention is, that my 851 set came with two 24 teeth gear (with crown) in black colour. I don't see them in blackbird's model, and they where also not mentioned in that colour on the instructions.

Have there ever been happening such re-designs other models? (other then element replacements like the Linear actuators in the 8043, and the issue with the pump in the 8110)

[AndyC]

Have there ever been happening such re-designs other models? (other then element replacements like the Linear actuators in the 8043, and the issue with the pump in the 8110)

Several. The Service Pack for the 8043 included a few minor design changes in addition to the redesigned linear actuator and the Emerald Night was revised in later versions to improve reliability when running motorised for extended periods of time. I'm pretty sure there have been others over the years but those two immeadiately spring to mind.

[rener]

One thing I also want to mention is, that my 851 set came with two 24 teeth gear (with crown) in black colour. I don't see them in blackbird's model, and they where also not mentioned in that colour on the instructions.

Have there ever been happening such re-designs other models? (other then element replacements like the Linear actuators in the 8043, and the issue with the pump in the 8110)

Well, according to bricklink most technic models of the years 1977-1978 were also released with black crown gears, see http://www.bricklink.com/catalogItemIn.asp?P=3650a&colorID=11&in=A .

And, 853 also had some re-designing, at least my (second hand) version contains an extra sheet with some modifications of the steering area. Mainly reinforcements of the steering column with bricks, no real technical redesigning.

[Jan]

Thanks for all the info, I think that solved my questions.

[yourohbricks]

While I was trying to get the digital versions of the instructionbooks of the sets I own, I found out that there are in fact two instructionbooks for the 851.

I own the instructions that fold out as a poster, with a complete 1:1 blueprint of the tractor paint, really sweet .

The second set of instructions I found on brickfactory and come as a traditional booklet. While I was browsing through this book, I not only found out that the build is in a different order, but there are some designchanges made that make the model more sturdy and playable (this model relies for it's playability highly on brick to brick connections).

There is in fact a sheet at the end of that scanned instruction booklet that let you convert the "old" version of the 851 lifting system into a "new" version, The thresher gets an extra part aswell to make it more sturdy (not shown on that extra folder).

Does anyone know about these two sets, and how I should see this in time?

Have changes in building technique and instructions been made before in what appears to be the same sets?

I guess, I got the set as a present somewhere in 1981, while peeron is showing 1977 as the release date.

I am just curious

There haven't been that many changes in building technique since then. Trust me when I say this: the more things change, the more things stay the same.