Backhoe LW-7 Backhoe Bucket Teeth

[traktorz]

We have a one year old Chinese made backhoe LW-7 (serial number LW7U116M 100 8100 405) from Shandong Sunco Agricultural Equipment Technology Co., Ltd (www.sdnyzb.com), that we're currently using together with our Foton Europard FT404 tractor.

Last year's working intensly through the tough Scandinavian soil from the ice age, the teeth did wear, as can bee seen from the images. What do you do when the teeth gets dull? Sharpen them? Weld on a hard surface? Replace them? If so, is this a standard teeth hole pattern, making the teeth easily available as spare parts?

P.S. My Google SketchUp drawing is not accurate, only a sketch made after a rough measurement recently.

 

[Bob Rooks]

Lots of wear left in those teeth. I've never heard of hard surfacing small teeth, usually just replacing them is more cost effective. However, not to say it couldn't be done. What I have on my ripper scarifier is a replaceable pin-on tip. You might be able to convert to something like that.

 

[RonMar]

1. weld, grind repeat.

Repeat step 1 untill desired shape is achieved. Repeat as often as necessary to maintain desired shape

 

[traktorz]

Yes, a friend with a mini excavator (german Terex TC20) has no teeth at all on his three buckets, so for some work that's OK. But for our forest road maintenenace, the teeth are very useful to work through the top vegetational surface.

I suppose welding new material onto these teeth is a good way to see for ourselves if it's practical, and if the material is suitable for welding on. I then read there are certain hardened welding electrodes to use. Unfortunately, we currently only have a MIG/MAG, but an inverter pin welding tool is on our purchase list.

Page 34, 80,81 in the attached repair manual from ESAB suggests various methods for welding. Welding electrods according to standards DIN E6-60, HV-630, DIN E6-65 are recommended, from what I've seen elsewhere.

Ref:

• Handbok för reparations- och underhållssvetsning - www.esab.se

 

[Bob Rooks]

Just curious, have you priced new teeth?

 

[Nuno]

don't know the prices for teeth in Sweden but here in Germany i can get similar Teeth for the LW Bucket from 5 to 12 Euro each.

Onlineshop für: Baggerzähne, Laderzähne, Verladeschienen, Gelenklager, Gelenkköpfe, Spannbuchsen, Gummiketten, Leitern, Bolzen u.v.m - Baggerzähne, Baggerzahn, Anschraubzahn, Anschraubzähne, Laderzahn, Laderzähne, Gabelzahn, Gabelzähne

 

[Rich Waugh]

Best bet, if you can get them, is to buy a set of new ones and then take your time finding someone who can hardface the old ones for less than shop rate. Perhaps a neighbor has a stick welder you could use?

I'd suggest first "buttering" the old teeth with a thin application of nickel rod or 309 stainless steel rod - I'm referring to stick welding electrodes here. The nickel or stainless rod acts as a binder layer to ensure that the hardface rod really sticks. Then do the build-up with overlapping courses of hardfacing rod designed for the purpose. Any good welding supply store should stock them.

Note that hardfacing rod is NOT cheap! It will cost more to hardface the old teeth than to buy new ones, but the hardfaced teeth will outlast the new ones by a factor of two or three to one, most likely.

 

[RonMar]

MIG wire is pretty hard. I have had good luck with it for hardening up wear surfaces that contact the earth/rock. Sounds like you at least have what you need to try it. Good job for someone who wants to learn to weld. I was teaching my grandson, and turned him loose on my FEL bucket edge and BH bucket teeth. He lays a few passes, which we discuss the quality of, then he deslags(flux core wire) with a die grinder with wire wheel. Then he lays beads in between. When done we gring the part back into the desired shape and edge. Inexpensive, but a little time consuming...

 

[Rich Waugh]

ER70S MIG wire is harder than most (though not all) common A-36 structural steels, but it is not really abrasion resistant like true hard-facing material. It is probably both harder and more abrasion resistant than the steel used to make Chinese bucket teeth, though - they seem to be pretty soft.

You can get hard-facing wire for a MIG, but it is not generally available in the smaller sizes like .023", .035" or .045". Since it is usually used in applications where the object is to cover as much area as quickly as possible, it is customarily available in sizes more suited to 300-amp and larger machines. That is why I recommend the stick electrodes and a DC stick welder.