Overstressing PTO U-joints?

[Rock knocker]

I wrote my post while you must have been writing yours

Rock knocker, thanks for the pointer there. I will talk to these folks and see if I wouldn't be best off with a 6 series shaft. They mention that one should reduce the HP rating by 40% for severe duty. I don't think I'm operating at a "severe duty" level, but it's not a bad idea to be a bit beefier. Series 6 is rated 64hp (PTO), and de-rating by 40% gives 40hp; tractor's PTO is rated at 43hp (it's an HST), so I'd be pretty close here. Also, the shaft length seems more appropriate: 65" open and 39" closed- I will remeasure, but I believe that I was about 58" open (maximum, a distance that I wouldn't likely see when in use, but it's the physical maximum based on my top link's extension); minimum number looks good as well; I'd have a normal working overlap of about 14" (vs. 6 1/2" with the series 4).

This year when I finally put a quick-hitich on our 1983 JD 950 ( a decision that was decades late!) I bought a Bare Compnay SB 6106 shaft with clutch. Like you, the length was a primary reason, and again like you, I was nervous about the the rating. I just loosened the heck out of it, and watch for signs of a little slippage after use. The slaesman at Washington/Snohomish says he can hear his when it slips, he may have better ears than me.

The new quick hitch and PO shaft is a dream to put on. The safety collar of the shaft is well thought out and easily slides out of the way to get to the universal connector, then goes back into place. I can do everything to hook the brush hog back up in about 5 minutes, versus about 25 minutes in days past, and I don't need to use a come-along and pry bar to help.

 

[Rock knocker]

Well, Washington Tractor punted on me. I'd asked if they could find out if I was OK to run a series 6 shaft on the Bush Hog 286 and they said they'd check with Bush Hog. The next day (they were prompt!) they left a message telling me to talk to the Kioti dealer (I'd told them I had a Kioti). Lame... SO, after more research (and everyone here's input) I think that I'm a fair bit wiser and should be able to locate what I need w/o the assistance of the "professionals."

I measured 58 1/2" from tip to tip: cutter disconnected, so it's perhaps a little on the long side (cutter sitting down on the ground). I think that in the EA video Ted measures to one of the notches; that adds 1 3/8", so 58 1/2" plus 1 3/8" comes out roughly to 60". Reading on Royal Brass' web site they mention that shaft overlap should be no less than 1/3 the compressed length. If I take my 60" and divide by 1 1/3 I get roughly 45" as my collapsed size.

I'm going to measure the possible extremes (based on full extension and collapsing of my hydraulic top link) just to check that the shaft overlap could be properly maintained.

Realizing that I've bought several implements from EA (and that their video was mentioned in this thread!) I decided to see what they offer in the way of shafts and, lo and behold, I see this:

Class 5 Eurocardan PTO Shaft for 5, 6, and 7 Rotary Cutters

Series 5. 45" collapsed.

Pretty sure that this is a perfect match. And looking at it I can see how TOTALLY wrong the previous shaft was (not only for MY use, but almost certainly for the previous owner's use as well).

Washington Tractor does seem very reticent to give advice on the proper sizing of after market PTO shafts, I guesss I could see why. That shaft from EA looks good, and I think that the Bare from Washington would be good too. Just as bad as too short is a shaft that is too long, and pushes your trans to death when you pull up the 3PH.

 

[DieselBound]

I'd like to get a QH but this cutter won't take one: Cat 1 or Cat 2 won't work From the looks of it I'm not thinking it would be easy to modify it. Fortunately the NX has extendible lower link arms. I'd give my left ... to have something like this on my B7800 (ANYTHING is better than solid lower link arms with turnbuckles!). I'll likely start thinking a lot harder about a QH when I start getting around to hooking up my new box blade.

I'm not seeing Bare listing for "SB 6106." There's "SB 6105." It lists shorter than the EA shaft, but Bare states that they measure cross-to-cross; I don't know how the EA one is measured.

 

[Rock knocker]

6105 is right

 

[DieselBound]

Washington Tractor does seem very reticent to give advice on the proper sizing of after market PTO shafts, I guesss I could see why. That shaft from EA looks good, and I think that the Bare from Washington would be good too. Just as bad as too short is a shaft that is too long, and pushes your trans to death when you pull up the 3PH.

The question that I'd put to them was whether a series 6 shaft would be OK on a Bush Hog 286. Nothing about length or anything else. In hindsight it's kind of a dumb question in that the only real issue is length: for some applications a series 6 is overkill, but as long as the length is OK it would work. That they or Bush Hog couldn't note this kind of says all I need to know.

What kind of price did you pay for that shaft? If it's close to what EA's is then I might consider going North (Washington Tractor up in Burlington). If it's a lot more then it's kind of hard to justify the added cost for nifty shaft guard (it is, for sure, nice!).

 

[Rock knocker]

$380. I bought it there because I could see exactly what I was getting and no shipping. I don't know if Tractor Supply sells anything similar. I do know they sell stand alone slip clutches, but that just adds another spline connection and vibration

 

[DieselBound]

Nothing appropriate from/at Tractor Supply.

 

[ericm979]

Agri-supply has a lot of different shafts available.

 

[DieselBound]

Yes. I have this one under consideration:

Ax6124Fd4 Pto Shaft | Agri Supply 3424

 

[DieselBound]

$380. I bought it there because I could see exactly what I was getting and no shipping. I don't know if Tractor Supply sells anything similar. I do know they sell stand alone slip clutches, but that just adds another spline connection and vibration

Was that $380 with tax?

Mount Vernon store gave me a price of $297: they didn't panic when I requested without specifying what it would be used on/for- maybe because I asked specifically for the SB6105? But this figure doesn't include shipping (guy noted this) or tax. I suppose that with shipping and tax added it's going to be around that $380 number.