Auger drives....giving up speed for torque??

[northern boy]

I will be buying either a PT425, PT1430 or a PT2445 for the purpose of digging post holes for fences and decks. I live in Ont. Canada and the digging is quite differcult in my area. I am considering using the tree planting head for the torque. I have used this drive last year with a PT1430 only because it came with the machine. It worked quite well after I customized it to swing both ways.
My question is how much speed am I giving up to gain the torque of the planter head?? Has anyone used or aware of the specs of the two drives offered by Power-Trac for the machines mentioned above?? I did phone PT directly and asked about RPM and torque of their drives but they don't seem to have specs on them. I was pleased with the PT1430 (12GPM at 2500psi) to dig my holes with the planter head but more RPM would be nice to help remove the loose dirt from the hole. Now I would like to try the PT425 because of it's smaller size and less weight. I'm just a little concerned that it's 8GPM at 2500psi might not be enough power for my tough digging conditions and will over work the machine or not get through all the holes.
Has anyone used the PT425 for this? How did it do? Any input on this would be appreciated.
Thanks, northern boy.

 

[KentT]

I have no experience with either the planter head or PHD, but I will offer that as I understand hydraulics, you would not be losing any torque going from the 1430 to the 425. What you would lose is the RPM with the lower flow...

With everything else being equal -- i.e. the same attachment and hydraulic motor:

Pressure (PSI) = torque

while

Volume (flow) = RPM

 

[Gravy]

I have a PT425. I built my phd with the same motor as the PT planter head. It turns too slowly to throw off cuttings from the smaller augers. It worked OK with the 24 inch planting auger the one time I found a fairly rock-free spot. Even with the 6 inch auger, it will still easily jam and stall in my extremely rocky soil (I don't think anything short of a rock drilling rig would really work well here). The planter head might make sense for 12 inch or larger holes in hard clay or similar conditions. For that kind of work, the added weight of the bigger machines would be a plus.

If I were to do it again, I'd use the smaller motor to speed up drilling post holes, and use the mini-hoe for planting.

Gravy.

 

[RegL]

I will be buying either a PT425, PT1430 or a PT2445 for the purpose of digging post holes for fences and decks. I live in Ont. Canada and the digging is quite differcult in my area. I am considering using the tree planting head for the torque. I have used this drive last year with a PT1430 only because it came with the machine. It worked quite well after I customized it to swing both ways.
My question is how much speed am I giving up to gain the torque of the planter head?? Has anyone used or aware of the specs of the two drives offered by Power-Trac for the machines mentioned above?? I did phone PT directly and asked about RPM and torque of their drives but they don't seem to have specs on them. I was pleased with the PT1430 (12GPM at 2500psi) to dig my holes with the planter head but more RPM would be nice to help remove the loose dirt from the hole. Now I would like to try the PT425 because of it's smaller size and less weight. I'm just a little concerned that it's 8GPM at 2500psi might not be enough power for my tough digging conditions and will over work the machine or not get through all the holes.
Has anyone used the PT425 for this? How did it do? Any input on this would be appreciated.
Thanks, northern boy.

I have the 1430 and phd with 12" x 4' auger. I have never used the tree planter. I have difficult digging also. lots of good sized rocks in most places. If I had it to do over, I would get the planter drill. I find the two way swinging to be a disadvantage most times. It makes it easier to get the auger vertical to start but gets it thrown off easily when you hit something. I'm going to modify my phd so I can lock the head up in one direction if I want. I don't often use much speed so that would not be an issue and more torque would be nice.

As far as 1430 verses 425, here's my thoughts. First off, you should make sure the 425 can carry around a 4' auger. It only has a 5' lift. my 1430 with 6' lift doesn't take the four footer far off the surface as I remember. Where you live, I would think you would need all of 4' depth for deck posts.

One of the big advantages of digging post holes with a PT is the ability to use down pressure. However, I find ,even with the 1430, I can get the front end of the tractor off the ground real quickly. The tractor also gets tossed around pretty good when it's real rocky. With a 425 at half the weight, this could get even more annoying.

 

[northern boy]

Thanks for your input...The biggest hole I would ever drill would be a 12", mostly 8" and 10" holes. I run into the same bad digging conditions as you Gravy and that's what concerns me about the post hole drive not having the torque to do the job.
P.S. do you happen to know approximately the difference in Rpm's with the two types of drives? ( given the same flow.)
I sold my last PT and now my option for this year would be a new PT425 or I have a line on a used (in good shape) PT2445 which would have all the power I would need and then some for post hole drilling but is a little big and heavy for alot of the jobs I do in residential niebourhoods. The up side of the PT2445 is a few attachments come with it(including the back hoe) and the whole package is about 50% more then the PT425 new......What would you suggest?

 

[RegL]

Thanks for your input...The biggest hole I would ever drill would be a 12", mostly 8" and 10" holes. I run into the same bad digging conditions as you Gravy and that's what concerns me about the post hole drive not having the torque to do the job.
P.S. do you happen to know approximately the difference in Rpm's with the two types of drives? ( given the same flow.)
I sold my last PT and now my option for this year would be a new PT425 or I have a line on a used (in good shape) PT2445 which would have all the power I would need and then some for post hole drilling but is a little big and heavy for alot of the jobs I do in residential niebourhoods. The up side of the PT2445 is a few attachments come with it(including the back hoe) and the whole package is about 50% more then the PT425 new......What would you suggest?

Backhoe. that reminds me of something else that may be useful. I have found some places where installing fence, the mini-hoe did a better job than the auger. It's pretty amazing how tight you can dig a 2' deep hole with that 9" bucket.

 

[BAGTIC]

I have a 14 inch auger that I use for tree planting and a 30 inch auger that I use for digging shallow beds for flower bulbs, etc. On my 425 I have not found that torque is a problem. If the engine is on fast throttle and the auger jams the torque will tip the tractor good, almost threw me off once. More torque would only result in lying on your back while drilling holes in the shy.

I think the problem of rocky soil will be be served by different cutters. I have considered an aftermarket carbide tooth and pilot set. Most of our big rocks are flat flagstone like pieces or limestone about the size of a dinner plate to a gabage can lid. The problem is that the pilot hits them and spins like a top without penetrating or fracturing them. Once the flighting works its way under most of the smaller rocks it does a pretty good job of lifting them.

I have not yet found an instance where I need a hole deeper than 30 inches. Certainly trees, fenceposts, etc. don't need anything deeper.