Alstor 8x8??

[treedave]

Gotta say the alstor has its place and its problems. I've driven one enough to get my Fmo on it and decide to go the alpine & trailer route. Looking at a big hp alpine and still trying to source a good 4-5t trailer (recommendations welcome). Have decide to go drag to start with and retro a cage drive later. This is due to finance and not being able to find a suitable off shelf driven unit. Have heard that Riko are looking at a driven trailer system, but struggling with the complexity/ longevity/cost/weight equation.any updates Jim?

 

 

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[RichardT]

I still think a mid sized dumper could be made into a good compact skidder

 

You'll occasionally see homebrews of this type on Blocket.se - Sveriges största Köp & Sälj marknad, also smaller ones designed for skidding elks to roadside.

 

The obvious advantage of a tractor front end is that it can do other stuff when not hauling a trailer. I've probably posted this eg before: Mactrac | Miniskotaren Mactrac

 

Then again something like the Kranman Bison front end could equally be mated with a simple skidder or loader back end....

[Chris Sheppard]

Gotta say the alstor has its place and its problems. I've driven one enough to get my Fmo on it and decide to go the alpine & trailer route. Looking at a big hp alpine and still trying to source a good 4-5t trailer (recommendations welcome). Have decide to go drag to start with and retro a cage drive later. This is due to finance and not being able to find a suitable off shelf driven unit. Have heard that Riko are looking at a driven trailer system, but struggling with the complexity/ longevity/cost/weight equation.any updates Jim?

 

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Our 4T weimer's been a good trailer on the whole. The wheel track could do with being about 6 inches wider and a steering drawbar would be nice but it's a scaled down big trailer rather than a scaled up small trailer. We've only got the 3m crane on it but as it's a cut down 4.1m e can retrofit the longer booms if we wanted to.

 

Did you ever see pics of the drive unit Steve fitted to one of the smaller JMS trailers? Worked well enough to push the tractor round just off the trailer wheels. Limiting factor with the JMS trailers was they were on quad type tyres so wuld have worn fairly quickly.

 

I still think a mid sized dumper could be made into a good compact skidder

 

You'll occasionally see homebrews of this type on Blocket.se - Sveriges största Köp & Sälj marknad, also smaller ones designed for skidding elks to roadside.

 

The obvious advantage of a tractor front end is that it can do other stuff when not hauling a trailer. I've probably posted this eg before: Mactrac | Miniskotaren Mactrac

 

Then again something like the Kranman Bison front end could equally be mated with a simple skidder or loader back end....

 

That Mactrac looks a simple enough thing.

 

Reckon an old compact tractor could be chopped about enough to make a front end not disimilar to the kranman front end. Can usually lose a good few inches off the bonnet before getting to the front of the engine.

 

I'd love to have the time and facilities to make a proper little homebrew thinnings forwarder but I don't think it's ever going to happen.

 

Best we might manage is to stick a steering drawbar on ours and maybe one day some wider offset rims and drive cages.

[Big J]

I'm disinclined to consider utilising and adapting an existing machine as I think that the principle of building a small basic, but tough forwarder should be doable.

 

Basic requirements that I would regard as being paramount.

 

* Ability to lift and extract up to 750kg product lengths, up to 4.9m in length (this translates to about a 50cm mid diameter sitka log at that length).

* Ability to extract approximately 3-4 tonnes per load.

* 6/8 wheel drive.

* Full cab, with heater and tool storage.

* Maximum weight of 2.5 tonnes gross to allow haulage to site by trailer and 3.5 tonne class vehicle.

* No exposed mechanicals, ie no exposed drive shafts and minimal exposure for hydraulic lines.

 

Beyond that, decisions would have to be made about drive. The Alstor uses drive shaft and direct chain drive, which is very effective at putting power down but at the point of articulation is very vulnerable. I like the idea of hydrostatic drive, but I must admit that I am not entirely sure how easy it would be to ensure one or more wheel wouldn't spin out, with the lack of a mechanic differential. The advantage (I feel) of hydraulic drive is that hydraulic lines are easier to protect and cheaper to replace in the event of failure.

 

Regarding the cab, I like the idea of having the engine under the floor/seat if possible as it will lower the centre of gravity, and leave space within the length of the cab for additions such as a hydraulic winch/tool storage.

[treedave]

Our 4T weimer's been a good trailer on the whole. The wheel track could do with being about 6 inches wider and a steering drawbar would be nice but it's a scaled down big trailer rather than a scaled up small trailer. We've only got the 3m crane on it but as it's a cut down 4.1m e can retrofit the longer booms if we wanted to.

 

Did you ever see pics of the drive unit Steve fitted to one of the smaller JMS trailers? Worked well enough to push the tractor round just off the trailer wheels. Limiting factor with the JMS trailers was they were on quad type tyres so wuld have worn fairly quickly.

 

Chris,

Didn't see the addition that Steve did. Know what you mean about the tyres though. Have looked at Weimers and Vreten. The We 5 looks good but the wheels / tyres would need changing and the draw bar cylinder / hoses looks a bit exposed. like the Vreten 700 as well but heavy and over large for job.

 

Know anyone bring Weimers in?

[Chris Sheppard]

Chris,

Didn't see the addition that Steve did. Know what you mean about the tyres though. Have looked at Weimers and Vreten. The We 5 looks good but the wheels / tyres would need changing and the draw bar cylinder / hoses looks a bit exposed. like the Vreten 700 as well but heavy and over large for job.

 

Know anyone bring Weimers in?

 

Have you seen the smaller, budget Vreten? Can't remember the model number but it's black and red instead of blue and yellow. 4T and 4m or so crane from memory. Tyres were a bit skinny though.

 

As far as I know, Andrew Holmes Forestry still do the Weimers. Not the best to get hold of by email though.....

[RichardT]

Two homebrew Alstor knockoffs, FYI:

 

[ame=http://www.youtube.com/watch?v=i_sVGPG5oA8]RF8 8x8 /3 - YouTube[/ame]

 

Xcat - 8x8 auf 4 Boogieachsen

[treedave]

Cheers Chris, will chase FMS about the smaller vreten, tyres are skinny enough on the 7t! Had some good service off Holmes in the past but usually involved multiple calls.

 

The home brews don't look too shoddy but can't see FC signing them off!

 

 

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[JimE]

We are still working on the idea of the small driven trailer for the alpine.

We really want to go with a PTO driven set up as most of the alpines have a ground speed PTO and it would be good to utilise that. The problem is balancing weight, price and quality.

There are PTO driven tipping trailers available on the market, but none are quite suitable for converting.

AGT 850 is about £18k+vat. One of our 3 ton trailers with a crane is about £8k+vat, if we added £6k+vat for the drive system that would be a total price of about £32k+vat. Cheaper than an Alstor, but would enough people buy it to make it worthwhile developing?

 

Before I worked at Riko I built a small hydraulic drive skidder from scratch. Cracking project, really enjoyed doing it.

Is there actually anyone who would stump the cash to build a rival to the Alstor? Always looking for another project....

Edited March 26, 2013 by JimE

[drythropple]

We are still working on the idea of the small driven trailer for the alpine.

We really want to go with a PTO driven set up as most of the alpines have a ground speed PTO and it would be good to utilise that. The problem is balancing weight, price and quality.

There are PTO driven tipping trailers available on the market, but none are quite suitable for converting.

AGT 850 is about £18k+vat. One of our 3 ton trailers with a crane is about £8k+vat, if we added £6k+vat for the drive system that would be a total price of about £32k+vat. Cheaper than an Alstor, but would enough people buy it to make it worthwhile developing?

 

Before I worked at Riko I built a small hydraulic drive skidder from scratch. Cracking project, really enjoyed doing it.

Is there actually anyone who would stump the cash to build a rival to the Alstor? Always looking for another project....

Have you any photos of your skidder?