JohanM. I am not familiar with this type of shear coupling.
It would seem to me that the plate face-to-face will have a lot of friction drag.
Will the bolts even see the force you are trying to limit?
Should not you insert a slick plastic disc between the face plates? Lube grease might just be squeezed out too much.
And if you would large drill bit taper chamfer the inner face bolt holes; more of the bolt shank will be exposed to the transferring force. Sheared; jagged ends then maybe not mar up the plate surfaced so badly.
Regards
Steve Unruh
The shear bolt is keeping the discs together so there will be no friction drag between the discs, there is a hair of distance between them too so when the bolt shears they do not grind against eachother.
The rebak-side axle goes in to the gearbox-axle about 2” and is supported inside the gearbox-axle with a bearing to make it not spin at all when the shear bolt is cut.
The bolt holes has to be just regular drill sharp so they cut the bolt clean off and ejects the head and the nut completly. Nothing left in the holes to scratch the plates and the holes should not be any bigger than the bolt.
If so, then it can be a little bit diagonal in the hole and increase the the shear area of the bolt dramatically.
I was trying to find something on youtube that shows this but of course I can’t find any.
The bolt shearing force in this case is axial and a snowblower shear bolt is usually radial but the principle is the same.
Does my bad explanation make sense at all? If not then I can make a video instead to try and show how it works.
There is a few things still to do but in essence it is done, here’s the first chunks coming
I put it on top of the chunkdrying trailer since the shoot out of the rebak had to be re-done, I removed it but chunking has priority. Right Göran?
My wife had to act camera(wo)man
Thank you Tom.
There is a little adjusting needed on the knives still (plus protections), it sometimes does have some fibres still stuck together so they are linked together, not sure why it is only sometimes. Perhaps a certain wood species with longer fibres.
This was aspen, rowan, alder and birch chunked.
Thanks for the offer
I think ill have to wait to next weekend, i have a big alder at my brothers place, and some thinner stuff on some field edges. Thinking about getting one of them fancy chainsaws people seems to use nowadays?
But I understand, I’d like to stumble upon someone having and not needing a good 65-70cc chainsaw so I can stick a 30-32” bar on there for my firewood cutting each spring, I can’t justify spending that kind of money on a new chainsaw when I spend less on a car it is definately not in the budget. Plus the fact that I would pretty much only use it in spring.
Only buy a good service and parts supported chainsaw. Buy quality.
Cry big; once.
Then use it yearly for 10-15 years.
I make-do with a 28"/71cm bars on all. Up thru 44" butt sections.
I’ve now seen the pictures of you. 28" then no bending too much and stooping. Safer actually than any short bar for us tall.
Long bars hard to keep track of that dangerous tip.
S.U.
I should check in my chainsaw pile, if i can find any Husky or Stihl that would fit you, any of those are pretty expensive as used also, but sometimes they can be found for the right price, some fixing and good for many years of use. Husqvarna 262, 270 are hard to find cheap, but indestructible, and will pull a 30" bar.
Thank you J-O, I guess chunks are needed. How long into the fall is is doable to dry chunks around here?
Yes, So far I only have Stihl saws but I am a little curious about Husky’s as well but I wouldn’t want a chinasaw because of the service/parts.
I would want to go up over 30” since I cut firewood hanging in the ’claw’ of the crane on the tractor wagon, it is becoming a nuisance to cut and then go back and cut several times on the same spot to get through.
Long bars is not in the culture here, I rarely see one over 18-20”.
It works with both spruce and pine, which have dried in the forest, and the advantage is that it is quite dry already.
I think my pendulum works quite well against hanging, I sometimes rush the car a bit when I see the temperature rise, however, it is rarely needed.
