Comparison Plastic versus Paper, I mean Metal.

[Soundguy]

</font><font color="blue" class="small">( So you really, really like sitting on that cold/wet/hot metal seat )</font>
They make padded seat covers as well as a padded pan seat for the oldies..

Soundguy

 

[Syncro]

<font color="blue"> " moot point as the electronic controls very likely won't be available anyway, and once the tractor is old and the HYDRO tranny goes out it is not cost effective to repair if you can get parts " </font>

<font color="black"> </font> If there is one thing I miss about the old tractors its the simplicity. All these frills, micro switches, sensors, plastic parts (opps /forums/images/graemlins/shocked.gif) etc sooner or later will need replacement. I guess bottom line is don't keep em too long, heck its fun to trade anyways /forums/images/graemlins/grin.gif.

 

[keeney]

My 1999 JD 4100 is mostly metal skins, but has a couple of plastic parts on it that were poorly designed and have cracked.

One is the cover over the tranny in the middle of the operator's platform. The bosses where the screws go through are too whimpy and the stress concentration there has caused them to crack.

The second is the piece of black trim around the 3-point control lever. It had a thin section where the piece that goes around the lever cracked on one end. I got tired of it vibrating and flopping around, so I snapped it completely off. The piece I broke off didn't appear to serve any useful function whatsoever.

Hopwever, I'm not happy with the painted metal, either. Sharp edges on metal are an invitation for the paint to fail at that edge (very high stress concentration at a perfectly sharp edge). Once the hairline edge opens up, moisture wicks in and the paint eventually releases back from the edge as the metal corrodes underneath it. The edges of all of the fenders are rusting.

Also, the black metal screens on the sides of the engine compartment are already rusting.

The paint job on my 410 loader was a joke - it was clearly painted AFTER assembly! The hoses are green, and under some of the tie-straps holding the hoses on, there is no paint on the metal (just rust).

So, I agree with the other poster - a poor design in painted metal or plastic will not last to look good as an "antique".

- Rick

 

[slowrev]

Syncro,
A good attitude fo one who likes to trade. I but equipment to use up or keep forever. Keep having to build sheds to put it in though /forums/images/graemlins/smile.gif

Ben

 

[slowrev]

I suppose the lovers of plastic have not spent much time under the hood of a 13 year old car. Many of the connector clips break off when disconnecting the connectors. Spark plug wire guides are brittle, etc...give me metal for long life.
I have never met a plastic yet that won't get brittle with age.
Not saying they don't exist, just never seen any and am very doubtful that they exist. Plastic has improved greatly over recent years, but.....

Ben

 

[eee]

Re: Plastic versus Paper, I mean Metal. *DELETED* *DELETED* *DELETED* *DELETED* *DELETED* *DELETED*

Post deleted by roughcut

 

[zipp669]

My 1999 4100 is doing the same things. Plastic has cracked in the same places. metal rusting. All with 710 hours. Still runs good.
When I got my 4500, I thought oh great, plastic, plastic everywhere. will surely be broke b4 long. but to no avail it still looks good with 900 hrs on it and no rust.
Now my 3710 Kubota is all metal and a rattle trap when running at 2300 rpm. but it has scratches you can see but is more sturdy than the 4500, the 4500 just shakes everything to death. The metal on the 3710 is in good shape and no real rust problems at 1250 hrs.
All the new tractors I am looking at are mostly plastic cept the Kioti, Century & Mahindra.
I dont no if it matters or just a matter of preference.

ZIPP

 

[slowrev]

Roughcut,
I am not questioning your knowledge or judgement at all. I am just questioning how it is determined that a type of plastic that has just existed a few years will last as long as metal ?
I seem to put 25 year shingles on my houses about every 18-20 years.?? Not plastic I know, but how are we to KNOW that a product that is new in existance will last 20 yrs or longer.
Simulations are great but not a genuine substitute for the real thing. Bumble bee's cannot fly right ?

I am not really anti plastic, it is fantastic material when used in the proper applications, I just don't think that on a tractor is one of those because I buy a tractor to last 20-30 yrs.

Ben

 

[keeney]

Plastic or metal can both be designed to last 25 years, but I don't see a lot of the things in the design of either in modern products.

With plastic, you have to over-design the part shapes to take into account that the material will get more brittle with age.

With metal, especially steel, you mostly have to take care of corrosion. Two ways to do that: either make it so thick that the corrosion can't eat away enough of it to matter over 25 years, or protect it with a coating. Problem is, the most common coatings just don't last 25 years under normal use. So, to last 25 years, will require careful maintanence of the paint.

I think that almost all instructions on trac tors and implements say to clean, inspect, and touch-up the paint after every use!

One of the things that is unfortunate about modern engineering tools is that they can tell the enginer _exactly_ how thick to make the part to make it mechanically strong enough. The bad thing is that this gives the engineer a false sense of thinking that is sufficient to build a durable design. Too bad most engineers don't use that fancy software to run the same design through with the plastic de-rated to its 25-year aging, heat, and UV-exposure strength. Or simulate what happens to a 16-gauge steel fender covered by paint with a hairline crack after sitting outside for 25 years.

 

[Soundguy]

</font><font color="blue" class="small">( The only knowledge you appear to have about plastic is from what you have used personally,I work in the industry and I have 1st hand experience with the manufacturing and testing etc. I know for a fact plastic exists that will hold up as long as metal and is stronger. )</font>

You're right.. he is talking about plastics he has experience with.. those that are commonly used in automotive / tractor applications. He didn't say that the 'super space age' plastic didn't exist.. just that we aren't seeing alot of it on our farm tractors yet. So far all plastic stuff I've seen on tractors starts to sun fade after a few years at best..

Soundguy