Chipper Question From Newbie

Mike K2 · Apr 19, 2012

Hello all, I am a newcomer to tractoring and have a question about a used Wallenstein BX 40 chipper that I've been trying to use. There is of course no manual.

When chipping branches up to around 2" everything is OK. But when I try something near it's rated capacity of 4" the shear pin shears. I've gone through 3 pins in less than an hour's work.

The first question that I have is what are the shear pins supposed to be made of? I've been trying to play it safe by using grade 3 (no lines) 5/16-18 bolts that are mild steel.

The second question is what is the procedure for setting the blade clearance? I read that it should be 1/32 to 1/16" but I don't know where that is to be measured at. The chipper seems very aggressive and whacks off about 1/2" per blade. Could that be too much? Does blade clearance effect chip thickness or is it determined by the amount that the blades protrude through the disc?

Any suggestions would be appreciated.

tractchores · Apr 19, 2012

I have the bx42 and love it. I also got it used. I found the manual online at Parts Books, Manuals & Instructions - Wallenstein

You can by the proper sheer pins there too. I have put some very big stuff trough mine, even manging to stall the tractor without sheering it.

Zebrafive · Apr 19, 2012

My BX62 uses 10mm shear bolts marked 10.9

Mike K2 · Apr 20, 2012

tractchores- Thanks for the suggestion, but after looking at the manual I don't think that the BX42 is much like the BX 40. The 40 is direct drive and it seems that the 42 is belt driven for increased speed.

Zebrafive- Wow! A grade 10.9 bolt is really strong. About 2 1/2 times as strong as a grade 3 according to this link- American Fastener - ASTM, SAE, and ISO Grade Markings

That sounds like the answer to my problem. I'm about 90% sure, but that other 10% could be expensive! Does anyone have a BX40 that you would be willing to check? I would sure hate to break something expensive.

jshwhite · Apr 20, 2012

I would also recommend adjusting the blade clearance. If it is taking 1/2" thick chips as you are saying, that could shear a pin when doing a big branch. Not familiar with that particular model though, so I can't tell you how to do it exactly. Hope you get it figured out!

tractchores · Apr 20, 2012

Mike K2 said:
tractchores- Thanks for the suggestion, but after looking at the manual I don't think that the BX42 is much like the BX 40. The 40 is direct drive and it seems that the 42 is belt driven for increased speed.

Zebrafive- Wow! A grade 10.9 bolt is really strong. About 2 1/2 times as strong as a grade 3 according to this link- American Fastener - ASTM, SAE, and ISO Grade Markings

That sounds like the answer to my problem. I'm about 90% sure, but that other 10% could be expensive! Does anyone have a BX40 that you would be willing to check? I would sure hate to break something expensive.

Not sure if you maybe read the wrong manual? My BX42 is direct drive with a sheer pin. I think the shredders (bxm42) might have a belt, but none of the chippers do. When reviewing I think there's some minor differences with the BX40 and BX42, but shouldn't be any to the drive train (basically the 42 now has something called a twig breaker, which is a piece of metal that the plate the blades are in goes through to break up any twigs that could cause jams).

Here is the link to that manual, which shows the adjustment procedure for the blades etc (I believe that should be the same between the models). http://www.embmfg.com/File.aspx?id=0f3a2527-274a-44d9-aa90-51e2e49d61ea&display=full

Mike K2 · Apr 20, 2012

tractchores- You're right, I was looking at the chipper/shredder images.

Would you be so kind as to check the shear bolt head and let me know what is stamped on it? Maybe 10.9 or 3 or 6 lines?

Thanks.

tractchores · Apr 20, 2012

Mike K2 said:
tractchores- You're right, I was looking at the chipper/shredder images.

Would you be so kind as to check the shear bolt head and let me know what is stamped on it? Maybe 10.9 or 3 or 6 lines?

Thanks.

Yup, I'll take a look when I get home this evening.

Stewie1 · Apr 20, 2012

I also bought a used BX40 this summer. I have a kubota B3200 and I can bog down and stall out with full capacity spruce. No shear pin issues.

I also have a wallenstein manual and what looks like the original shear pin in the PTO shaft. Is the PTO shaft original to the unit - no idea!

The manual seems to suggest the shear pin is Gr 8.8 M8 x 45mm.

Two photos attached that may help, one of the manual and one of my possibly original bolt that has no markings.