Shear Pin Shocker

[JohnMiller3]

<font color="blue">(...$8 or $6 per shear pin ...) </font>

Hey Bill...

You're not using that broken calculator again... Are ya? /forums/images/graemlins/wink.gif

 

[Henro]

<font color="blue"> You're not using that broken calculator again... Are ya? </font>

Nope! Just repeating what was reported above in this thread. I can't comprehend it, but I don't doubt what the guys are reporting... /forums/images/graemlins/frown.gif

The CHEAP ones were $5.50 each...amazing...

 

[JerryG]

The Bush Hog model 2101 uses the same gear box as the model 2102, but the 2101 uses a lighter duty pto shaft. This is the reason that the 2101 uses a pin without a head that has a 3/8" shaft and is necked down on the threads to 5/16". Bush Hog <font color="red">does not</font> recommend the threads on the yoke be drilled out and the pin replaced with a 3/8" bolt because of the lighter duty pto shaft. Bush Hog will not warranty the pto shaft if the pin is replaced with a bolt.

 

[JohnMiller3]

/forums/images/graemlins/laugh.gif
<font color="blue">(...Grade two bolts go for $1.19 per lb ...)</font>

Hi Bill...

I had quickly seen this and forgot about the rest of the thread... /forums/images/graemlins/blush.gif

 

[JohnMiller3]

<font color="blue">(...has a 3/8" shaft and is necked down on the threads to 5/16"....) </font>

What part of the bolt is in the "shear" area?

Without physically seeing it... off the cuff, why couldn't you use a standard Grade 2 - 5/16" bolt? (without drilling it out)

 

[JerryG]

John,
One side of the yoke is drilled 3/8" and the thread side of the yoke is 5/16". The pins shears at 3/8" on one side and shears at 5/16" on the other side. According to BH the combined shear of 5/16 and 3/8 is the required amount for that pto shaft. A total shear of both sides at 3/8 would be to much for that shaft. If you just put a 5/16" grade 2 bolt in, then the 5/16 would only be tight on the threaded portion thus the input shaft would have slop on the yoke all the time.

 

[JohnMiller3]

I understand the taper you're saying, but won't the "nut" keep the tension on the 5/16" bolt... thereby attenuating any "slop"?

 

[JerryG]

All of the un-threaded portion would be slop.

 

[Slamfire]

At $6 to $ 8 a pop, you'd think a slip clutch could be payed for inside a week. /forums/images/graemlins/smirk.gif

 

[kensfarm]

"I got the slip clutch anyway"

Henro.. I was wondering.. w/ the slipclutch.. how many shearbolts have you gone through?

I can't believe $8 a pop.. w/ that price I know one post hole that would have cost me almost $50 to dig.. lot's of roots.

 

[mwood]

This seems to be a case where proprietary setups cost everyone more in the long run. Why can't they standardize a system for something as simple as shear pins?

By the way, I have seen this setup on many applications where they not only hit you for $ at the beginning, but every time something as simple as a shear pin snaps, they gouge you again! Very agrivating....

 

[Hoeman00]

Why not drill it out to 3/8 and use 3/8 all-thread, this has a minor diameter of 5/16 which would be a little easier to shear.
Bolt houses sell 3,6,12' lengths and 6' is than 1 shear pin.

 

[Henro]

<font color="blue"> Henro.. I was wondering.. w/ the slipclutch.. how many shearbolts have you gone through? </font>

Maybe someone with more holes under thier beit and a slip clutch on thier post hole digger can chime in here. I don't have enough holes dug to really know how well the slip clutch actually works. I got it because my neighbor recommended that I get one.

Only dug about ten or twelve holes with mine so far...

Anyone out there have some real experience with a slip clutch on a phd? Worth it? I guess it is but ... but that is just opinion really. We some experience to do the talking /forums/images/graemlins/smile.gif

 

[gerard]

i have a low end phd but I can use cheap grade two bolts with lock nuts, Takes about 30 seconds to swap when they shear and they cost around 30 cents each. If I had to pay $8 I'd have one hell of a lot of $50 post holes!!!!!! I wouldn't even think twice about getting a slip clutch. You can get them for about $100 and at $8 each it'll pay for itself pretty quickly, especially if you have rocky ground. I just did 5 holes for an addition on my land. Took me 5 hours and handdigging. Did 8 holes for a friend and it took about 25 minutes for all of them. He didn't have a rock bigger than an apple on his land!! My luck I have a rock farm.................

 

[kemartin3]

An update with a little more information. As I had said earlier, my PHD2101 came with a 3/8" grade-5 bolt in the shear bolt hole. I verified with the dealer that the person setting it up had not drilled out one side of the yoke. So I sent a note to Bush Hog via their web site. I got a call from BH tech support in Selma, AL the next day. Henry, the BH rep, was very helpful. He confirmed what Jerry has been saying: the PTO shaft supplied won't stand up to the double shear (both sides in shear at once) of a full 3/8" bolt, even grade-2. That is the reason for the stepped pin. The PTO shaft is a model T10 (Comer brand I believe, as least the manual that came with the unit that discussed the PTO shaft was from Comer, who supplies the gearbox). He told me to have my dealer order a replacement shaft assy and send the warranty claim to his attention. He suspects that the supplier had put the wrong/bad yoke on mine. Excellent customer support.

As an aside, I've used my 2101 with an 18" auger (BH only specs the 2101 for up to a 9" auger) to drill nine 48" deep holes. Granted the dirt was soft and I didn't hit very many rocks, but I have not sheared any of the stepped shear pins.

Hope this helps,
Kevin