Designing a forwarder [Edit]

[mog5858]

i will say rubber tracks are not the way to go from my experience. frend has a little ride on skidsteer and well i seen it eat tracks up in 100 h. we have has new one just brake but they are a little diffent than what was showing but at 1000 a set it don't take long to go to the poor house.

[Just Me]

I love this little unit, thinking about making it into a skidder by making the bed removable and using 2" box tubing Reese style recievers accept a protective plate like on the back of a cable skidder. There is room under the bay behind the crane for a hydraulic winch. 









Not exactly a forwarder, but plenty stable to pull a small log bunk trailer and there is a fairly versitile machine.

Ironwood

Ironwood, I swear you have more cool junk than anyone I have ever known! That thing is awesome. How much will the crane lift? Reach? Very cool......

[snowstorm]

Ironwood:

The next time you see a source for tracks can you please send me the link.  I have contacted a couple but as with most companies when they find out I am in SA they stop communicating.
jameskingpe@yahoo.es

have you tried camoplast?sherbroke quebec? i think they bought bombardie line of tracked equipment

[Ironwood]

The guy I bought it from thought the crane only lifted 980#, but it was in Kg, ( not marked kg) otherwise he would have kept the thing. I took one look at it and knew better. I have tested it, will go about 2500 lbs. Dangerous Dan (FF) has one rougher condition w/ out the crane. We both have replaced the upper track idlers (missing in one photo, that is as I first saw/ found it), w/ a heavy cast iron kiln cart wheel w/ HUGE rolling pin bearings. Little 25 HP starts no matter how cold, with no problem. Amazing.

I will send you some links on tracks, those adds were everywhere in the hard copy truucktradwr before they stopped printing it.

[pineywoods]

I keep thinking about the Ford 8N tractor I have in Wisconsin.  That old design could be improved on a bit starting with low pressure balloon tires on the front and be an excellent small scale low impact economical machine.

Man does that pic bring back some memories. Those tracks were made with a thick rubber  industrial belt down each side and bolted on all metal cross bars. Bunches of them around here in the late 40's and early 50's. Used as skidders. Best I remember, they were made by Tidewater engineering. The real weak link was steering. Mostly steered with the brakes, but 8N fords had lousy brakes.

[Just Me]

When I was a kid I was helping a felow skid some logs with an old Oliver with that setup. He caught a tree with one of the tracks and quick as a flash the front end swung around and hit another tree and broke the tractor in half. Had a hell of a time getting that thing out of the woods in two pieces.

[Dangerous_Dan]

Reid-
It's only 19 hp. More power would be great.
The bigger units are Hydrostatic drive but don't go any faster.

DD

[Regi]

Hi all,

It's been a while since i posted my initial post,
but a lot has happened since then and i wanted to do some proper research in the field before i come back with something.

First off, thank you all for your comments, they have been very helpful in many ways.

I'll try to cover my research a little bit and then come out with what i've got so far so that maybe
i could get some of your opinions

The first and i guess the main thing is that i have switched the main topic of my degree
from a small-scale forwarder to a bigger one (here i'd like to stress that i don't mean the size of the machine, rather the productivity and i'll explain what i have in mind with this later).
I've found a collaboration partner amongst companies who manufacture forestry machines - Komatsu Forest
and decided to continue working with them on this project.
One of the main reasons for the change was because i wanted to keep my project in the realm of forestry as in business.
And i understood (while talking to people that it wouldn't be possible with smaller machines - as in with low productivity, not size.) And the sustainability or low-impact part is what i want to look into  considering THESE machines, since i see them as something that needs an investigation. (hope i'm making myself clear here)

Price of the machines was another problem - since not all forest owners can buy even a small machine,
i saw it more appropriate to consider contracrors as the main users in this case and then forest owners as someone who can hire them rely on them a 100% and the machines that they use to get the job done in the most positive way as possible. (I won't go into depth on this though).

// What i've done so far:

I've also had insightful discussions with forestry experts (from an education field) about soil mechanics,
how weight affects soil (pressure bulbs...), what happens with wheels and bogeys and soil and fuel usage.

I also had a chance to go out and see a thinning operation in progress with a harvester and a forwarder (which i had a chance to drive and operate for a little bit).

I went to a factory to see how forestry machines are made and put together.

I've researched into the history of machines used for logging (extraction) and how they evolved
"Tracks in the forest - Ken Dushka and Hannu Konttinen" was a good help with that.

I've also read "Positive impact forestry - Thom J.McEvoy" to better understand low/sustainable/positive impact forestry, not to mention a lot of time researching machinery and forestry in general on-line.

// Some of the The outcome (really very briefly)

- Forest as an organism/ Forestry
This is a big field and i won't go into this here, because you are people who know a lot more about forests than i do, i think it would be silly if i started talking about microorganisms and how root systems work and what affects can heavy machines do. (but i will present this during my local presentations, because people who will be listening don't know this and this the basis of the project)

- Weight & Soil
Disbalance, heavy weight, and small ground pressure points create ruts.
Those we can try to solve with bogie tracks, but they cost and add weight to the machine too.

We can decrease the mass the machine can handle, but then it becomes less stable (The tipping weight might be to big and then we have oscilating hydraulics and so on...) and it becomes less productive of course.

// A very good comment i got from one person was :
"...more extra weight isn't wrong if it's in the right place"
(this is something i will looking into - deviding the weight, but keeping the productivity)

- Productivity
The most important issue from a user's (a contractor's) point of view is productivity. If a machine handles less weight it means that it's less productive. That means it needs to go into the forest more times to handle the same load as a more productive machine could handle.

e.g.

14t load / hour
8 t load / hour
would mean that a machine needs to go into a forest twice to get the same load.

We can make it faster
8t load / 30 mis = 16t/h
but that would require a bigger engine to get the machine faster - price, weight...

And a more powerful machine would require bigger pipe size for flow. (don't have the right words for this, but will work on it for my research presentation)

- Hydraulics

e.g.
we have a power of 40kw - at 200 bar pressure with 40l/min flow
if we want 80kw of power with 200 bar pressure, we'd have to have a flow of 80l/min.
That would mean an increase of pipes.
(I'm looking into electricity solutions for this)

// History
I didn't think that this will be useful when i got the book (mentioned earlier) but what i saw kind of amazed me. The evolution from animal/steam/machine logging is quite obvious and expected. The thing that disturbs me is that machines used for logging were never meant to do that. If you look at the "after-war" machinery, they are mostly the same trucks used during war with some minor changes to do logging. So how can one expect a machine (a tractor basically) to be low-impact if it wasn't really designed to do logging in the first place? And what we're doing now is just trying to improve machines which were not meant to do the job of logging in the first place. And we expect them to be low-impact. So with that in mind i'll try to aproach this problem. What would be the ultimate solution for logging. Taking what we have now as a... reference, but coming up with my own vision for the task based on the insights and research.

// Insights (This is more what i saw as some issues with current models that will be helpful during the design process apart from the main re-design)

- Machine lifecycle (what happens if it breaks/ serves it's purpose)?
- Designing the system/principles of how it works, instead of focusing on the interior of the cabin and so on...
- Visibility (wheels, loader with graple) they all have to be seen perfectly (not blocked)
- Loading (more agility needed)
- Loading/Unloading (doing the same job twice)
- Cabin flexibility (different people with different needs)
- Controlls (intuitive)
- Maneuverability (Moving, turning)
- Technology (noise reduction, electricity vs.hydraulics)


That's really a brief sum-up of what i've been up to for the past few weeks.
And as usual - all comments, suggestions and critique is welcome. Maybe something i have to look into or have missed.

For the next couple of weeks (not counting this one) i'll be working on developing some concepts for the forwarder (sketching probably) later i'll make some quick prototypes.
I'll try to share everything with you.
And next monday i'm having a research presentation, so i'll try to share a pdf with you as well.
Unfortunately i won't be able to share some pictures and videos that i have taken so far, since i've got a non-disclosure agreement.

Thanks for the support!
/Regi

[Ed_K]

Thanks for the update.I for one,will be intrested in your future machine.Someday someone will be moving logs startrek style.

[snowstorm]

so.......is it going to be valmet red?????

[vt_forest]

Take a look at F4-Dion forwarders.  The one that I have has a 292 chevy gas engine in it.  The thing is very easy to work on and most of the parts can be found at Napa.  Not sure of the ground pressure but it has tracks all the way around and seems to float where my 440A would sink out of sight. 

The bad is the thing was built for thinnings in softwood.  The loader was not built for larger wood.  Tracks are very costly and lots of moving parts makes for lots of repairs.

[snowstorm]

dont forget to put a blade on this fancy new valmet your building.