Snowblower Shear Pins and Being Gouged!

OKK group... top line questions is what kind of steel is used to make a shear pin?

Background.. we just received over 28" of snow here in the mountains outside of Boulder, CO in the last 24 hours. My big Honda Snowblower (HS 828, 8HP,

28" auger) broke the both auger shear pins while blowing my 250 foot driveway.

On the internet, you can buy 10 pins for $5.50, but I needed them now. Here in Boulder/Denver, one guy was charging 4.00 for the pin and 3.00 for the nut. Another was charging 9.00 for 4 pins and 5.00 for 4 nuts -- but he was out of stock - sold out.

Now I understand capitalism and I don't want to talk about that.

What I want to know is why not use a standard grade 2 M6 hex bolt and nut from Home Depot for .17 cents for the "pin" and 20 cents for the nut. Obviously, I want a "cheap" bolt so it WILL shear...

Will this work to get me thru blowing the rest of the driveway until I can order "genuine Honda replacements pins"... or do I really need "genuine Honda replacement pins?

Steve

Reply to
Steve Koschmann
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A stupid redneck style idea is to take cutting pliers and cut that cheap bolt and then your shear pin. If the force to cut them is about same, then use the bolt.

I would shell out $4 for the proper pin as insurance against engine damage, personally, and would not try to save $3.83. Then buy those

10 cheap pins to keep as spares. i
Reply to
Ignoramus12805

I would suspect the shear pin may be just a standard bolt. Look at the markings on the head of the shear pin and see if they correspond to some specification you might recognize...

Jerry

Reply to
Jerry Foster

Ditto what Igor said. I've had to replace the differential on a Craftsman tractor mounted snowblower as I picked up and wrapped a aluminum rod around the driveshaft that was buried in the snow AFTER the shear pins and spent well over $100 (if I remember right). Same thing could happen if you used a standard bolt. I found that MTD shear pins at Home Depot were identical to the Sears shear pins but about 400% cheaper. You may want to consider that. I think that if I absolutely wasn't going to buy a proper shear pin, I would be at least looking for a brass bolt. Nahhhhh, I'd buy the shear pin...

Dave

Ignoramus12805 wrote:

Reply to
Dave Young

Get a common nail that is close to the right size. Drop it in and bend it over. Repeat as needed.

Reply to
Ken Davey

My 10.5HP/ 30" snowblower used 1/4" grade 3 bolts as shear pins. Pick yer poison, but I'd have no qualms with using hardware off the shelf if I were in your boots. The lower grade stuff will shear easier.

The shear pin has little to do with saving the engine, rather it limits the damage to the impeller when you hit a chunk of firewood or a bit of 2x4 that won't go through the impellers. I have fried the odd belt from this, too, without taking out the pins.

If you have misc. solids like firewood and lumber on the driveway, you should also see to having a mig welder on hand as well as an assortment of hammers, vice grips, and crescent wrenches to pound the metal back in line with.

FWIW the shear pin that was used on the towbars we used to tow a 7000 lb gross weight aircraft was a longish 10-32 size bolt, arranged so that it was in shear in a single point (Canadair CL41A Tutors, if it matters), and they held up to quite more abuse than I would expect from a bolt of that size.

Cheers Trevor Jones

Reply to
Trevor Jones

I need a shear bolt once for my snowblower once and didn't have any. I took a regular bolt and ground grooves in it at the same place as the one bolt that I was replacing. I did order and install the correct shear bolt later. You can either grind or hacksaw 2 grooves in a bolt. The grooves should line up with the od of inner shaft. (or ID of the outer one). Then order the ones of the internet.

Wayne D.

Reply to
Wayne

Shear strength of steel is about 75% of the tensile strength. If I were in your situation I would use low tensile strength steel of the same diameter as your original shear pin. My reasoning is that Honda would not use more expensive material if it could avoid it. And using low strength steel will assure that if the pin shears, it will not bugger up the shaft.

Dan

Reply to
dcaster

My John Deere 46 inch front mount blower (on a JD 318) uses bog standard

1/4 - 20 1 inch long soft bolt with a self locking nut for a shear pin.

Just installed the 9th of twelve that came with the blower. However other JD parts make up for it. Two pressed steel bearing cages for $25, they just happen to also fit JD combines so that makes them worth that.

Only 12 inches here when the early December storm went through here. I think I am the only person in this town that has this setup.

Hugh Quincy, IL

Steve Koschmann wrote:

Reply to
Hugh Prescott

Ken, this is probably not a good plan. Nails tend to be a little bit hard to aid in driving them in without smashing. A nail made shear pin will likely shear at a higher force than intended.

Steve

Reply to
Steve Smith

I don't know where you get your nails, but the only hard nails I have ever found were for nailing into concrete. No WAY you'd mistake them for regular nails.

Nails bend. They are soft. If they were not, one could not straighten a nail and re-use it.

Good luck finding a 6 millimeter nail, too.

Cheers Trevor Jones

Reply to
Trevor Jones

A threaded bolt is not what you want as a shear pin. The thread tends to break under oszillating forces quicker than a smooth surface. Also, a shear pin has to have a nice fit and not just a "throw-in"-fit. Make one out of plain vanilla CRS or free machining steel, that's what most shear pins are made of.

Nick

Reply to
Nick Mueller

It isn't an all or nothing thing, Trevor. Maybe instead of the word hard, I should have said tough. My point is that nails are not made of low carbon steel and they are not annealed; I'm pretty sure their shear strength is significantly higher than a shear bolt. Compare riveting with a nail vs. a real iron rivet--a real rivet works lots better.

STeve

Reply to
Steve Smith

Definitely not a standard bolt. IIRC they are very soft with a hardened exterior. You don'twant them to deform before yielding, and you want them to yield before the expensive parts. The cheap pins from Home Depot are fine - MTD makes a lot of the Craftsman stuff.

Reply to
clare at snyder.on.ca

Nails are a lot closer to the right spec than a class 2 bolt.

Reply to
clare at snyder.on.ca

Do you like the equipment? If you do, why are you quibbling over a few bucks to do it right? Just buy the right freaking pin, it's a hell of a lot cheaper than whatever it's protecting. For the record, it's also unwise to replace a fuse with a penny to keep an overloaded circuit from blowing fuses.

Reply to
Dave Hinz

This one of those ass/gater/swamp things. A nail starts looking realy good when a replacement pin is halfway accross town and there is two feet of snow everywhere.

Reply to
Ken Davey

If you insist on being cheap :) ,don't mine replacing the shear pins often, and want to play it safe, buy aluminum bolts.

Reply to
Jon

Excuse me? Really?

Reply to
Jon

And when you're kicking yourself in the ass for blowing up the gearbox on your snowblower because you didn't buy a 5-pack of shear pins last time, well, ...

Consumables need to be stocked.

Reply to
Dave Hinz

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