Basketball sized limestone rocks either deflect the bit, same as a pneumatic mole/missile, or the bit will crack the rock and still possibly deflect. It's not that uncommon to bore half way through and have to pull out and move over 12" bc of a rock. It's easier/quicker to move than it is to try to go through a stubborn rock.
We had one yesterday where we hit a limestone shelf and the bit got bound up and the torque from the machine snapped a drill rod in half. I don't know what a shale shelf will do. We haven't run into that yet. On Thu, Mar 23, 2017 at 7:48 AM, Adam Moffett <dmmoff...@gmail.com> wrote: > What happens when the topsoil contains rocks the size of basketballs? > > What happens if it hits a shelf of shale? > > They never seem to have that in the demonstration videos. Google fails to > answer these questions for me. > > > ------ Original Message ------ > From: "Joe" <j...@highspeedcrow.ca> > To: af@afmug.com > Sent: 3/22/2017 10:54:09 PM > Subject: Re: [AFMUG] Vibratory Plow > > We did extensive testing… > > > > Our LM42 we bought was great with direct burial, but not good with a chute > for ¾” pipe. > > It was reliable, but in harder ground it was an issue – no setting for the > angle when going shallow. > > We even custom built a chute… great concept, but not practical for our > ground conditions > > Single tires with good rubber is OK, duals are better for harder ground. > > > > *We went with a zahn (mini skidsteer) that is tracked and articulated. * > > The angle of the plow can be fully adjusted to the conditions > > With a serrated blade, we can easily go through roots… *even a couple > inches of frozen ground* > > We use a “Bullet” style to pull the conduit with a carrot or kellum grip > (Chinese finger trap) > > https://www.youtube.com/watch?v=r9JhOQYxbwM > > video is for a silt fence, but it gives the idea of why this works very > well > > A team of 2 guys can easily do 5-8 houses in a short day (conduit). > > Tracks, and articulation…. Is the secret. So is slow and constant speed > > Rushing the install….. results in stretched/broken conduit. > > > > We also bought the “mighty mole” attachment for compaction boring under > cement driveways. > > This wasn’t cheap, but it is very effective / clean / fast > > https://www.youtube.com/watch?v=1fGpRuNXjnM > > make sure to sleeve under driveways with good conduit before pushing > through fiber or a smaller conduit where needed > > > > For some of the bigger acreages, we pull in with the RTX1250 and use a > bullet with 3/4 conduit or chute with 1.5” > > The ground disturbance is more, but doing this… it impresses the farmers > when we are “rolling black coal” > > > > We also protyped a conduit pressurized with water and a jet where we > attach a carrot. The water helps for sure, but at some point… the added > work for the water/equipment was just a little bit too much to be > practical. Another one we looked at was sending a stream of water down the > plow itself, but then we need the water source moving… and it used a lot of > water to be effective. Think of how a big tree mover sends the big knifes > into the ground easier with water…that was the model we compared it to. > Very functional… just impractical in practice. > > > > > > *From:* Af [mailto:af-boun...@afmug.com] *On Behalf Of *Jason McKemie > *Sent:* Tuesday, March 21, 2017 2:55 PM > *To:* af@afmug.com > *Subject:* [AFMUG] Vibratory Plow > > > > I'm trying to decide what make/model of plow to get. The options, as I > see them, are the Vermeer LM42, Ditch Witch 410SX, or Case Maxi Sneaker. > I'll be using this for customer drops as well as some main-runs. > > > > I like the mini excavator attachment for the LM42, although I don't know > how limiting this will be for the machine if I'm also using it for customer > drops. The drill attachment for the 410SX also seems like it could be > useful. > > > > Anyone have experience with these machines? Recommendations? > > > > Also, does anyone know what model of Case Maxi Sneaker this is? > > http://i.imgur.com/APCL4TK.jpg > > > > Thanks. > > > > -Jason > > > > > >
