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Made by Monkeys

The Rust & Squeak of a Brand New Mower

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tekochip
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Platinum
A Litle Dab Will Do Ya
tekochip   10/9/2012 8:49:36 AM
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It seems a shame that they couldn't include a little grease or at least a note to add some, since there may be hazardous shipment laws about including grease in the carton.

naperlou
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Blogger
Light rust often a problem
naperlou   10/9/2012 10:03:40 AM
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Vern, while there should have been grease on the part, it may have just been left off of your unit.  Sometimes when you get into a new car the dealer will tell you that there may be coat of rust on the brakes, since they have not been used.  This is not a problem.  A few applications of the brakes and the rust is off.  Most uncoated metal parts will acquire some surface rust.  It would be interesting to know, from either the store or the manufacturer, if this was a problem others had reported. 

JimT@Future-Product-Innovations
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Blogger
Substitute Plastic discs-?
JimT@Future-Product-Innovations   10/9/2012 12:34:42 PM
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From your description, the steel spacers sound like they were disc-like in appearance to provide a smooth plane for wheel rotation-? (to eliminate wheel wobble-?). If that's the case, I would have used polycarbonate (Lexan, or other PC) in the design. Much more water-friendly moving thru a wet lawn.

Rob Spiegel
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Blogger
Re: A Litle Dab Will Do Ya
Rob Spiegel   10/9/2012 1:59:02 PM
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Good point, Tekochip. However, if they decide not to include grease before shipping, it would make sense to be very clear to the buyers that this needs to be added before usage. Including a package with grease would help as well.

Charles Murray
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Blogger
Re: A Litle Dab Will Do Ya
Charles Murray   10/9/2012 7:16:34 PM
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I agree, Tekochip. At the very least, a note of explanation or direction would be appropriate. No one expects a brand new product to squeak.

Battar
User Rank
Platinum
Stainless
Battar   10/10/2012 9:19:01 AM
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My guess - the designer specified stainless steel spacers, the manufacture didn't check the quality of the material  at incoming inspection.  The (won't mention country of origin) spacer manufacturer got paid for 18/8 stainless, supplied sub-standard parts, and kept the change. Our company has had a similar experience with a split-pin supplier.

sbkenn
User Rank
Gold
Re: Stainless
sbkenn   10/10/2012 10:26:50 AM
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I bought a bunch of hydraulic type stainless fittings to go on a boat.  I asked if they were available in 316 grade.  The supplier said that they could get them marked as any grade, but reckoned that they were all the same.  Guess which country of origin !

Larry M
User Rank
Platinum
Re: A Litle Dab Will Do Ya
Larry M   10/10/2012 11:21:35 AM
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> "A little dab'll do ya."

No it won't. Not unless you have a thorough understanding of the plastic involved. Nylon, for example, is formed of long, twisty molecules that intertwine with one another, resulting in a mostly-ridgid, somewhat flexible, self-lubricating solid. But if you use any lubricant, it allows the twisty molecules to disengage one another, resulting in a soft, mushy material unsuited for most uses.

Now, as I get it, this application doesn't use the commonly used shoulder bolt, a bolt with increased diameter for a region starting at the head and supporting the wheel, with a smaller diameter threaded region opposite the head. These bolts need only a nut as additional hardware, but obviously need the shoulder to be just a bit longer than the wheel's axle bore.

Instead, this application uses a bolt of constant diameter, with an added sleeve to perform the shoulder function. This situation gives an additional point of friction. Is the wheel rotating on a tightly-clamped sleeve (plastic on metal) or are the wheel and sleeve rotating on a tight bolt. This latter condition would result in a metal-on-metal contact which definitely should be lubricated.

My guess is that it's the former situation--the sleeve is tightly clamped when the bolt is sufficiently tight. There should be no noise from a plastic on metal contact. I wonder about end contact. No one has discussed the question of thrust. I'm wondering about either end of the wheel hub rubbing on the bolt head outboard or the mounting plate inboard. If there's a metal washer at either end, sticking to the wheel and rubbing against the underside of the bolt head or the mounting plates inboard, it certainly makes sense to lubricate these metat-to-metal contact surfaces.

 

 

 

Vern Klukas
User Rank
Iron
Re: A Litle Dab Will Do Ya
Vern Klukas   10/10/2012 3:05:50 PM
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Thanks for the comments, guys. Funnily enough, moments after this blog story went live I got a Linkedin note from a engineer at Fiskars, wanting some more info. So I'd say Fiskars is stepping up to the plate here.

Just to respond to the comments, I don't think the design was intended to be lubricated.

The spacer is a sleeve, not disk like. The wheel's end thrust is taken direcly by the frame cheeks, which are wider than the wheel hubs, which the bolt & sleeve clamp.

The sleeve doesn't rotate, so the running surface is plastic on metal. I think the squeak was the result of the soft rust being compressed and then torn away in a stick-slip manner by the action of the wheel. The wheels have substancial running clearances, both axially & end float.

The wheels could be nylon, but I think not. The material seems more like a high density polyethylene or possibly a polyurethane.

Yours

Vern

 

Bob Salter
User Rank
Iron
Re: A Litle Dab Will Do Ya
Bob Salter   10/11/2012 9:07:07 AM
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I had a similar experience with a green lawn spreader with the name of one of the most respected manufacturers of turf products. It's wheel bearings were simply a steel shaft in a plastic bushing. After its first use, I followed the operating instructions and cleaned the bearings with a garden hose to remove fertilizer and lime. I even went beyond instructions by blowing air into the bearings to remove water and dry. Next, a liberal application of WD40 and a couple spins of the wheel Fast forward a year and time to fertilize again. Both bearings were locked from rust, making the device inoperable. Even WD40 would not penetrate and loosen the bearings. My initial thought was why someone would make a product to be used in a wet environment that would be  succeptable to rust? I complained, got a refund check, bought a different brand, maintained it the same after use, and have been using it for ten years. It had the same basic bearing design, but maybe the materials were different.

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