Olathe Model 12 Chipper Rebuild

[spelly]

I'm in the processes of rebuilding an Olathe Model 12 Chipper. During the disassembly, I discovered that one side of the drum shaft is badly warn/abused. Does anyone know if the shafts are replaceable and if so, how. If not, do you have a suggestion how to get it so it can hold a bearing again?

Further complicating the matter, the drum weighs about 450 pounds. The shaft can only be turned on a very large lathe if attached to the drum.

The shaft is 2 7/16" in diameter. The drum is 13" in diameter and 12" wide.

Any help is greatly appreciated, thanks,
Steven

 

[2treeornot2tree]

I can't tell from your pictures. You may have to replace the whole drum and shaft assembly. You maybe able to find a welding place that can repair that too.

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[CalTreeEquip]

There is no way to repair that and make the shaft as strong as it needs to be. Olathe chippers are very rare so I doubt you will find another drum for it. This is a no fix situation.

 

[2treeornot2tree]

I disagree. A weld would be stronger then the shaft is. I have done it before and have had no problems

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[CalTreeEquip]

We just went through a situation like this with a Morbark 13. The opinion of my mechanic, who's opinion I trust over all others, was that building it back up and regrinding it would weaken the shaft at the point where the old steel meets the new. I know that weld can be stronger then the steel you are welding but its kind of a myth because the steel you are welding is weakened. Which explains why I have to fix so many welds that hold up fine but break around the weld.
You don't want to take chances with a 1000lb solid steel drum spinning at 2000 rpm's. That's how people get killed.

 

[spelly]

Time for the follow up photo.

I had the shaft welded and turned. As an added bonus, the work was done at a shop that specializes in balancing all types of rotating precision equipment. It's obviously overkill to balance a wood chipper drum to the same standard as a airplane engine turbine -- but that's what these guys do. For comparison, turbines (and my drum) are balanced to a standard called ISO G1.0. Car tires are balanced to ISO G40. A car tire is allowed to move 40x farther off the rotational axis.

If you look at the photos on the Hi-Tek Balancing web site, my 450 pound drum is puny compared to the stuff they normally deal with.



After a lot of painting and reassembly, I'll be up and running.

Thanks everyone for the helpful info.
Steven

 

[CalTreeEquip]

The question is, would Hi-tek rebuild an aircraft prop shaft like that?
What did it cost?
Be sure to run a tap through all the bolt holes before you put it back together.

 

[Mike Boyer]

Okay, I know this is an old thread, But since I found it doing a search, and since most folks in the "Maintenance" area of tree equipment Will see Worn Shafts periodically, I thought I'd put in my .02...
To say that a Weld Repair is Unacceptable, or that this is a "No Fix Situation", simply Isn't correct. With all due respect, I understand the position that "Weld repairs fail", and they Do Fail when they are performed by someone who is untrained or doesn't follow the applicable procedure. That said, there are Many High Quality Weld/process repair methods (Metalizing for one) in use every day on everything from large industrial equipment ( Like 500 HP electric motor shafts or the County's Tub Grinder drive shaft) to Precision High RPM assemblies such as Gas Turbine shafts. Being involved in repair welding for 30+ years, I can say this; I have witnessed weld repairs on everything from Diesel Crankshafts to Recycling center flail grinder Shafts, all with No Failures.
So Sure, welding equipment in the hands of a novice is never a good idea. Quality procedures in the hands of a qualified person yields quality work. Don't fear Welding!
I know someone will say Metalizing/spray repair is garbage, but again, It all comes down to the process and the "skill of the craft". BTW, that is a good looking repair on the Olathe, I would assume it held up just fine. Regards, Mike

 

[spelly]

Okay, I know this is an old thread, But since I found it doing a search, and since most folks in the "Maintenance" area of tree equipment Will see Worn Shafts periodically, I thought I'd put in my .02...
To say that a Weld Repair is Unacceptable, or that this is a "No Fix Situation", simply Isn't correct. With all due respect, I understand the position that "Weld repairs fail", and they Do Fail when they are performed by someone who is untrained or doesn't follow the applicable procedure. That said, there are Many High Quality Weld/process repair methods (Metalizing for one) in use every day on everything from large industrial equipment ( Like 500 HP electric motor shafts or the County's Tub Grinder drive shaft) to Precision High RPM assemblies such as Gas Turbine shafts. Being involved in repair welding for 30+ years, I can say this; I have witnessed weld repairs on everything from Diesel Crankshafts to Recycling center flail grinder Shafts, all with No Failures.
So Sure, welding equipment in the hands of a novice is never a good idea. Quality procedures in the hands of a qualified person yields quality work. Don't fear Welding!
I know someone will say Metalizing/spray repair is garbage, but again, It all comes down to the process and the "skill of the craft". BTW, that is a good looking repair on the Olathe, I would assume it held up just fine. Regards, Mike

Dug up this old thread looking for the before and after pics.

 

[spelly]

I dug up this old thread looking for my before and after pics.

If anyone is curious, the chipper has worked flawlessly since the shaft repair. I only wish I had more HP to drive it. And fewer trees to feed it.

Welding repair and balancing was done by HI-TEK Balancing, Inc. Lunenburg, MA. Full disclosure: Other than appreciating their fantastic work and fair pricing, I have no financial, personal or business connection to these people.

 

[flatbedtommy]

Just out of curiosity due to looking and I did the same with mine but could never get it re adjusted correctly to chip properly and I've tried adjusting both the drum and bar with no luck any chance you could help point me in the right direction on adjustment