flashhole
Addicted to ArboristSite
I bet that homeowner was glad you took the job. Did you get an "after" pic?
......The chain cuts in a very different way from normal chain. It doesn't throw chip, it grinds. The biggest surprise is that you cant dross cut with it in the normal sense. If you lay it across a log and try to start cutting it will just start smoking and throw nothing, not even dust. If you lean on the digs it grabs and stalls. I thought the 044 might have been not enough saw, so we put it onto a snellerised 660 with a 7 pin rim. Same story. You have to use the chain pretty much the way they do in the rescue vids – the tip 5” of the bar only. I think this is a result of the weird geometry of the chain. You have to use that top few inches, and 'saw' across the cut in bigger cuts....Shaun
leave the geometry alone
use it as designed, cause it works that way
You may make an expensive lesson for your self if you get it wrong
Rep for your investment and your time to show us
I lucked into a bucketfull of damaged RD chains a while back that a fire dept. was throwing out after they were quoted a price on repairing the chains. They were all 60-link and I found enough good teeth to transplant to make a dozen or so 72-link chains. I grind them (with diamond wheel or dremel bit) a little less aggressive than RM and they cut much slower than sharp RM or RD, but I have lost very few tooth inserts. The inserts come off more readily when they have been ground back a lot, as there is less surface area for the joint. The inserts will stand up to a lot of dirt and sand, but they peel off if snagged on hard steel, such as high-tensile small diameter fence wire. They will cut limestone, but not silica-bearing stone.
Well, with a short gap between christmas and new years I've managed to find an hour to sit down, pull some pics off the camera and do a bit of typing.
The first job for the chain was a pretty awful stump. I get maybe 3 or 4 jobs a year like this and I dont look forward to them. Big stumps I refer to guys with big stump grinders. My machine is just a 20hp stump humper – self propelled and great for stumps up to 2', but not a big machine by anyones standards.
You know the site is going to be bad news when there's a 25 foot ladder involved. This particular site had a stump about 20' down from ground level next to a house. The photo doesn't really show that the stump is on a small ledge which then drops off sharply and becomes a slope that goes all the way down to the river. The ledge is bedrock. The owner had tried a lot of companies to get them to remove the stump so he could do a building extension, everybody had said no. There was no access for a crane, and even if there was the ledge was too precarious to drop a stump grinder down there. Everything would have to be taken away. Tree companies had looked at it and said no. In the end, the owner spent 6 weeks excavating it by hand down to the bedrock (dug out about 3' of sandy rock filled soil) and bucketed it down to the slope below, then hired a chainsaw for a few days and blunted a lot of chains and got nowhere. The entire stump shown in the photo was originally underground to the height of the retaining wall beside it.
The only good news for us was that he'd spent all those weeks excavating by hand. The sandy rock filled soil sitting on top of bedrock was bad news, and the stump itself was full of sand and rocks. It's hard to put a figure on a removal like this, but it's pretty easy to start at $1,000 and work up from there. In the past I've used upwards of 20 chains trying to cut out stumps like this.
We put the chain on an 044 with a fresh engine and plenty of pulling power and set to work. Started making cuts in the roots, some as little as 2”, the bigger ones about 18”x14”. Some were submerged in sand, some had grown over rocks. Most were sitting on top of the bedrock, and I ended up digging a few trenches right through the rock with the chain.
The chain cuts in a very different way from normal chain. It doesn't throw chip, it grinds. The biggest surprise is that you cant dross cut with it in the normal sense. If you lay it across a log and try to start cutting it will just start smoking and throw nothing, not even dust. If you lean on the digs it grabs and stalls. I thought the 044 might have been not enough saw, so we put it onto a snellerised 660 with a 7 pin rim. Same story. You have to use the chain pretty much the way they do in the rescue vids – the tip 5” of the bar only. I think this is a result of the weird geometry of the chain. You have to use that top few inches, and 'saw' across the cut in bigger cuts. When you use it this way, it's very aggressive! It really wants to pull the saw right out of your hands. And it does cut reasonably fast. It's more like trying to cut through a log with a grinding disk on an angle grinder than a normal chainsaw chain though....
I got used to the technique after a while though it's a bit disconcerting. We ended up making 25-30 cuts through roots, in the sand, and cutting through rocks as well. Then we had to rip the barrel up. The carbide chain was tedious here, so we used it to cut through all the rock/sand encrusted outer layers of the barrel then switched to another saw with a normal chain. It saved a lot of chains and time that way.
The we ran out of camera battery because I forgot to charge the camera the night before. The whole job took 4 hours including setup, cleanup, and getting all the gear up and down the ladder. Total saw time was about 45 minutes. The truck could not be parked close to the cliff. We ripped the stump into about 10 pieces. The whole stump and roots were lifted up with ropes by hand, there was nothing to rig mechanical advantage off. For reference, the stump/roots weight in at 950kg (about 200lbs) when dumped. Very dense hard awful wood. My initial impressions of the chain were a bit disappointing. I was really surprised that you couldnt cross cut with it at all but had to use a sort of continuous bore cut technique. Will look at changing the cutter geometry. The toughness of the chain was impressive though....
No discernable wear. We cut through lots of sand and rock impregnated wood as well as cutting sand and cutting rocks. The chain stretched quite a lot during use. I guess I adjusted it 8-10 times. Each time it was hanging about 1/2” off the bar. That's a lot of stretch! If it keeps up I might have to take a link out of it. It's already beyond the half way point of the adjuster on the saw on the first use.
Shaun
I had to climb a pretty long learning curve before I liked using the Dremel-type tools. I will list a few observations for whatever they are worth. The Dremel models need to be the variable-speed type with ball bearings. They need to be slowed to about 12K or 15K RPM. If the Dremel is fixed-speed, Harbor Freight sells a nice speed control that can handle up to 15 amps. Use a foot switch so both hands can be dedicated to grinder placement and control. The Dremel saw chain guide (like the Granberg or Stihl guides on their 12V units) is worthless since it doesn't straddle the bit, and it is impossible to keep a uniform hook. The best guides are the ones on the 12V grinders sold by Oregon and many others, since they rest on both the tooth and the depth gauge. I plan to re-engineer the Dremels to use the Oregon-style guides. I use only the diamond bits, whether for carbide or steel teeth. They run much cooler and keep their size and shape. My chain vise (for both filing and Dremel grinding) is an old Stihl wide nose sprocket without the sprocket. A bolt through the end-most rivet hole tightens the rails to clamp the chain. An illuminated magnifier (another HF item) with a 100 watt compact fluorescent lamp is mounted above. Wear a good dust mask. A carbide resharpen takes a little less than twice the time for steel teeth. I never put a stone or a file to a tooth until it is squeaky clean. I now have a USC so that is easier and quicker. I like the carbide chains for stumps and wood that has spent some time on the ground. I find that my stump technique makes for less work than the cleanup usually required after the stump grinder leaves. I dig down a few inches all the way around the stump and clean away dirt. If the stump is 2 ft or larger, I make 2 vertical noodle cuts like an X. I then horizontal plunge cut from my dug line toward the center with a downward slant and pivot the bar until it approaches the dug line, and next make a fresh plunge to the center,.etc... When finished There is a dished-out area that I fill with dirt and move on.Nice score on the chains! Does it take long to do them with the dremel diamonds? I had a go at doing a normal chain with a dremel once but I couldnt get the hang of it. Do you know your approximate sharpening measurements? A pic of a sharpened cutter would be greatly appreciated.
What are you using your chains to cut and how has the experience been for you?
Thanks,
Shaun
I'll ask it anyway though. In a situation like that, why not use a gas cut off saw? Just keep cross cutting it every which way as deep as you can, then pry/bust the chunks out with a six foot pry bar and a pick, then go at it again. Those things cut concrete and cast iron pipe, seems like they could be used for that sort of dirty and rocky job.
It's an idea that has been tried before, but I havent personally tried it. I dont have a gas cut off saw, but you can hire them in aus for $100~$150/day depending on the size of the saw. They measure the blade before hire and charge you for wear on top of the hire. From what I've read the standard diamond blade doesnt do much good in wood, but there is a heavier duty blade available that has big chunks of carbide in it. The blade was $400 last time I checked. You could pick up a good used demo saw for about $800 in aus, new I think they're about $2500. If i had a gas demo saw I might be tempted to buy one of the expensive blades to give it a go but probably not.
The other problem with the demo saws is that the usable amount of blade ends up only being about 4 or 5 inches depending on the size of balde you've got. You can hack and slash away, knock some out with an axe and keep going, but that's starting to sound like a lot of work. The other problem is the overall size of the cutting head of the saw can be as big as 20" depending on which model you have. That means no tight access, and you wont be able to get in under roots to undercut, or between roots etc. I've tried using circular saws with mixed success for similar reasons. You obviously wont be able to use this tool for ripping logs/stumps either, it's roots only.
I've looked at these a few times;
The arbortech petrol allsaw
[video=youtube;aIzjQXk-Veo]http://www.youtube.com/watch?v=aIzjQXk-Veo[/video]
[video=youtube;WOdNkncR9i0]http://www.youtube.com/watch?v=WOdNkncR9i0[/video]
It's an australian company, their website is here;
Arbortech
I figured if you got one you could probably make good money on it doing stumps, roots and some demo work. Even the biggest demo saws cant cut all the way through a double brick wall from one side. I could never get pricing on one because I dont think they made it to production but I'd expect pricing to be somewhere around $5k including the saw. No idea on blade life/price but I'd be expecting 'high, and not a lot'. They did go into production with a much smaller electric version of this saw that retails for $950. It doesnt come with the masonary type blade from memory, only a wood blade.
An interesting looking tool that could have some application, bu will obviously never be even half as good as a chainsaw. Looking at the mechanism I'd guess they had a lot of reliability issues.
As an aside, it's surprising how often I get a call from someone asking me to cut a root out of a tree that's still standing so they can put a path in or whatever. I'm talking major roots on large tree, right next to the tree. Of course I say no which surprises them. What do they think is holding the tree up? They usually end up going ahead anyway with axes or whatever.
I try to explain it each time, that the tree might not fall over today but with the right combination of wind/rain/time that tree will fall over and destroy their fence/house/kill their kids etc. They try to say they will accept all responsibility and I should just cut the root. I tell them that would never stand up in court, and that as an expert I would be liable for the consequences of all my work since they are obviously not competent to decide what is safe or not. Oh well.
Shaun
Shaun I see from your pic of the RDR chain that it has the humped bumper link with the extended tail. I am curious about how far the bumper tail extends relative to the top plate edge when the chain goes around the nose of the bar. Before I try to bore cut with RM safety chain, I grind off enough of the bumper tail to match it with the depth gauge as it goes around the bar nose. This makes for a smooth bore cut that feeds easily. I got onto this while modifying various chains for carving with dime tip and quarter tip carving bars. You can use a depth measuring gauge on the bar nose to compare the distance from tail tip to nose rail with distance from top plate edge to nose rail. My ultimate smooth boring chain is the triple hump safety chain with the bumper tail contour-ground to the same height as the depth gauge. I do this with the chain mounted on the bar. I manually advance the chain past a grinder positioned at the tip of the bar. I use this method to optimize tooth geometry for carving.
I see what you mean Shaun
that chain is going to be the wrong pitch before you wear the cutters out
I can see you with a chain beaker and spinner making two skip tooth chains out of that one before this is over
Enter your email address to join: