Pros and cons of using a lo pro ripping chain system.
GB extra thin bar designed to run Stihl 3614-63PMX.
When entering the world of chainsaw milling the term ‘ripping chain’ can be a bewildering one. Plenty of info online and of course plenty of contradictions to muddy and confuse things.
Really ripping chain is simply this – a micro or semi chisel chain filed to 10 degrees instead of the usual 30 degrees. That is it in a nutshell and it really is no more complicated than that. All filing principles stay the same except for this 10 degree angle.
Chisel chain and ripping
Have tried full chisel ripping timber and unless the timber is very soft ie. redwood soft, it seems to cause a lot of vibration. The manufacturuers seem to agree on this point as all ripping chains are converted micro or semi chisel chain. So if you are going to adapt an existing chain don’t adapt a chisel style chain.
Lo pro Ripping Chains
This is another potential internet rabbit hole to venture down only to emerge with more questions than you entered with 😉
Stihl 3614-PMX – this chain cuts beautifully out of the box to give a smooth and even board. Developed between Logosol and Stihl this chain is our favourite when it comes to milling timber on an oversize set up.
‘Special Picco longitudinal saw chain with narrow cut and high cutting performance, mainly for use in conjunction with longitudinal cutting devices as well as mobile small sawmills such as Logosol. This semi circular toothed chain is characterized by a low vibration level and soft cutting behaviour.’
Oregon 91R – Better suited for smaller milling rigs ie. 25″ and under. Depth gauges seem to be overly high to take as much of a ‘bite’ as the Stihl PMX chain.
‘Oregon 91R Low Profile Ripping Chains are specially designed for use with portable chainsaw mills and for all applications where cutting with the grain of the timber is required, rather than across it. Standard chassis and cutter parts are used, the cutter grinding angle is the only difference from standard chains.’
Granberg 3/8 lo pro – Granberg adapted ripping chain does work well however sometimes the adpatation to cutters can be fairly crude and it is more of a nuisance to sharpen.
‘Adapter scoring and clearing cutters enable a faster cut yet maintain a smooth cut face and smooth milling action’
Pros of lo pro ripping chain:
- Takes a very slightly narrower kerf (only 15% less than a 3/8 standard chain)
- Reduces strain on the powerhead
- Increases milling speed by approx 20%
Cons of lo pro ripping:
- Increased chain stretch even with Stihl PMX
- More expensive
- Chain has less strength than standard 3/8 and .404 – so hit something hard and there is more chance of chain breakage. Heavy handed operators will struggle as there is less margin for sharpening and milling errors
- Less stay sharp ability than the larger chains – larger chains can take more punishment than lo pro chains
So in conclusion – lo pro milling increases milling speed and decreases kerf wastage however there is less margin for errors and as usual for all chainsaw milling your chain sharpening must be spot on.