Which crusher to produce BRF (Raméal Fragmented Wood)?

[izentrop]

a single operator really struggles to provide ...

Hello Ahmed,
It is more motivating at 2, but it is not a criterion to save energy.
Only you can prepare the branches when the engine is not running.

Perhaps less obvious to restart an internal combustion engine than an electric one?

[Ahmed]

Hello Izentrop. You write:

It is more motivating at 2, but it is not a criterion to save energy.

The user-friendly aspect does not come into play in terms of energy, but optimizing the power supply reduces the overall operating time and therefore the fuel consumption; the goal being that the "energy" factor is as modest as possible with a view to distancing itself from the usual model.
The preparation of the branches can indeed very well be done alone and must take place (unless practical impossibility) before crushing.

As for starting, it is very easy: it is a small displacement engine (208 cm3) and the centrifugal clutch eliminates the need to drive the rotor; in addition to the little effort required, starting is instantaneous and trouble-free every time, because it is a "kinenveut" engine. .
Therefore, I do not hesitate to start it up, even for a reduced quantity of branches ... The use of this type of equipment is very different from heavy models which require heavy logistics (such as the regrouping of operations size). On the contrary, it adapts without worry to partial grindings and "without premeditation", thus allowing great flexibility in the use of time and the possibilities or requirements of spreading.

[Ahmed]

The only defect of this grinder, minor but annoying, is the system for fixing and adjusting the cap of the ejection tube. The four nuts attached to the inside of the duct create regressive jamming primers (from downstream to upstream). In addition, the adjustment is carried out using two plastic head bolts which loosen without any hesitation with vibrations.
So I cut the nuts to level the internal wall; Regarding the axial fixing of the cap, I shunted it from above by connecting the rest of the bolts; Regarding the adjustment, I tried to extend the stroke of the arc of a circle in which these bolts move, but finally, certain constraints mean that there is no room to install an external device ( otherwise, I envisioned a single blocking, with effect on both sides, by eccentric). Therefore, I opted for a central system, offset downwards: a round rod which engages in a hole, itself drilled in a part under the constraint of a spring ... "cold" , it works impeccably: it is the operating mode of the putty guns that I took again; in operation, unfortunately, the vibrations of the cap, amplified by the removal of the nuts from the axle, cause sliding and opening "full pot".
So I have to take it all from the beginning and first make a swivel device worthy of the name, without play and resistant *, then I will test the locking system again and if nothing changes, I will stay in the 'spirit of rapid blocking without element capable of unscrewing, with a notching of the rod V and a latch of complementary shape which comes to engage there.
It is obviously a rather tedious job, because very time-consuming in view of the small volume of the materials used, but I do not intend to "let go" and am more stubborn than these bits of metal!

* I lean towards the use of a technical plastic sheath around a steel axis: the elasticity of this material should allow me to have a tightening effect on the axis, lastingly eliminating any play.

[Ahmed]

A photo to better understand the current state of the ejection chute cap, as described in the previous message:

Coming soon, the stages of modification, a world exclusive!

[Ahmed]

Something promised, something due, little guys!

As I wrote above, the priority is to set up a pivoting system without play and without parts liable to come off unexpectedly. The technical constraint being to banish any protuberance inside the chip ejection pipe in order to prevent the appearance of jams.
On the photo below, I present the soul of my device: at the top, a pivot assembly and, below, the second disassembled pivot to better see the assembly of parts. The idea is that the technical plastic cylinder (I will have to try to identify its nature, because it is recovery) will tighten elastically on its axis (in semi-hard steel), this all the more so since it is fitted tightly in a ring. It is easily understood that the middle part will be welded to the ejection tube and that the female part will be secured to the cap. This last point posed a little problem because how to assemble everything without making a removable (which would complicate the creation unnecessarily: an irremovable assembly is more robust, less subject to vibration, especially since there is no imposing technical reason this constraint, excluding the final assembly ...). Progressive welding is not possible as it is, since the pastic would be destroyed by heat, but the presence of these sleeves is essential for the precise centering of the cap ... Damned!

You will soon know how I got out of this "suspenseful" dead end!

[Ahmed]

On the first photo, we see that the plastic sleeves have been replaced by wooden lures, longer, so as to keep the whole in the right position and can be easily removed afterwards (this was all the easier as the partial combustion had produced a serious play). At the foot of the discharge chute, the real sleeves await their installation. On the right, the cap has been gratified by 10 mm in width on each side in order to spare the place of the external supports of axes; as the cutout shows, I kept a part of the original side plate because I had stalled on it to adjust the whole in the starting dimensions. In the process, all the parts were welded to their final location and, after cooling, the plastic rings fitted in the greenhouse in their respective housings.

The second photo shows the finished assembly without painting, in order to see all the reconstruction work and the multiple inserts. On the ground, two "tools" essential for "baking" short waste (one is enough, obviously, but it is better to have one in reserve: the first must have ended up in shavings in an instant of distraction ... .

The precision of the fixation is very satisfactory due to my precautions and the very gentle rotation: I am satisfied with this result. However, the tests carried out immediately after, although showing a lesser vibration, this does not really change the previous behavior: engine idled and therefore rotor stopped, the cap remains at the desired angle, at mid speed, therefore rotor in movement, everything is fine too (which is progress compared to the initial state before modification), but, engine fully (therefore in normal operation), the slight unbalance of the rotor is amplified by the length of the chute and causes inexorably the sliding of the adjustment. I will therefore have to find a different device to secure the cap at the desired angle ...
But this is another story...

[chatelot16]

i have a big agram shredder on tractor http://www.agram.fr/materiels-agram-mac ... 600-1.html

the height adjustment of the chute is remarkably simple: a spring pulls the chute up and a chain pulls down, with a hook that allows you to choose the length of chain ... drawback you cannot change the adjustment of only one chain link at a time ... sometimes it lacks fine adjustment ... but it works and it does not go wrong

on the other hand, the pivoting adjustment on the vertical axis is woefully bad! it does not hold up ... I had to modify ... no tightening with small ear nuts as original, but real big screws ... drawback you must have a real key to make the adjustment , but at least it holds

[Ahmed]

Regarding the second point, I believe I have finally resolved the issue.
Your adjustment system is indeed interesting, but supposes (if I understood correctly) the locking of the pivot point ...
The lack of finesse of the adjustment is less annoying than poor performance of said adjustment.

I am currently hesitating between several solutions: 1- a cam system which blocks a connecting rod; 2- a nut locked in rotation by a spring and a threaded rod; 3- a device similar to that which I have already made, but in which the round rod is replaced by a bicycle chain with welded links and a blocker by pivoting of opposing bottom teeth ...
Solution N ° 1, I have already used it successfully: the adjustment by pivoting the lever allows a perfect adjustment of the desired pressure, but it is an assembly which seems complex to me for something so small ...
The N ° 2 has the disadvantage of being slow to maneuver and relatively complex also ...

Perhaps I could take inspiration from your formula: the cap spontaneously tends to open until it aligns with the chute and so it would suffice with a retaining chain ...
I have to move quickly enough, because I would then take care of the hay scarifier.

[Ahmed]

To move the grinder, you have to weigh on the handles of the device, which is not very comfortable. From the start, I therefore considered adapting a third removable wheel which would transform the whole into a cart: on hard and smooth ground, it would then suffice to simply push the crusher.
I had started to prepare parts, then suspended the project, before resuming it in recent days to finally complete the modification.
The principle is simple: two U-shaped slides are tailor-made to receive the upper plate of a wheel on a vertical pivot (recovery). Part of the support is welded to the stand, the other being screwed onto the body of the device (the bolt comes out inside a hollow external reinforcement); the whole is secured by two crosspieces perpendicular to the slides.
The assembly of the wheel consists in slightly lifting the visible part on the photo and sliding the plate in the slides until it comes to a stop; at this time, the lock is released and comes to block the plate on the other side. Removal consists in pressing the locking lever to raise the notch and practicing in reverse of the assembly.
It's the locking system that gave me the most trouble: I started on an indexing finger, but I didn't have the corresponding fine thread tap . After quite a few unsatisfactory attempts, I finally decided on this DIY toggle lock. Finally, it is rather better, since it is more convenient to press it than to pull the button of the indexing finger * ...

* Or, it is advisable to choose an indexing finger with locking in erasure position ... a more discreet and more "elegant" solution than the one adopted here.

[Ahmed]

After use in "transport" mode, the roulette wheel performs its function perfectly, even on grassy terrain. Having to press and push (or pull) at the same time was physiologically antagonistic, therefore painful, whereas now it has become really very comfortable ...

To tap the threads that receive the two bolts of the rear fixing lugs of the wheel slide system, I had to remove the belt housing and I noticed the presence of black rubber powder. The belts therefore skated during the previous jams and, contrary to what I wrote, the centrifugal clutch did not intervene during these episodes, which is ultimately normal since the engine speed did not drop significantly.
It is a good thing and a bad thing: the good thing is that the engine is protected against knocks or blockages detrimental to its integrity; the bad news is that if this parameter is not taken into account by the operator, the belts may not last long. For the moment, the belts show only signs of moderate deterioration, and what is rather encouraging, since I changed the cap, I have not encountered any jamming: as what this improvement was fully justified ...