Backhoe Build A Backhoe For PT425... It Could Happen

   / Build A Backhoe For PT425... It Could Happen #81  
David, What is the lifting capacity of the 425? I noticed that you are using some heavy duty steel . by the time you add up all the steel and cylinders and hoses and valves, and the side legs, I believe you will be close to your limit. Are you going to sit on your backhoe, or operate it from the PT seat. Even the small commercial add on bachoes, weigh from 1500 to 2500. lbs.
 
   / Build A Backhoe For PT425... It Could Happen #82  
For those of us that are unskilled, there is always a crutch, a fix, a gadget. The circle cutter that I used with my plasma was so simple. It cost almost$.01 cent. I drilled a small hole in the center of the circle that I wanted to cut, and then bent a heavy duty wire 90 degrees at 1/2 in. I then put the 1/2 in side of the wire in the hole, and bent the wire in a circle for the torch head. I bent the wire the correct distance to give me the size hole that I wanted. I then put the torch head in the loop, and cut around the circle. It worked out to allow me to weld in the sleeves for the pins.
 

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   / Build A Backhoe For PT425... It Could Happen #83  
This is a picture of a professional plasma circle cutter. Could also used with torch.
 

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   / Build A Backhoe For PT425... It Could Happen #84  
This picture is a straight line cutting guide for torch or plasma.
 

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   / Build A Backhoe For PT425... It Could Happen #85  
Another one.
 

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   / Build A Backhoe For PT425... It Could Happen
  • Thread Starter
#86  
The 425 will lift 800 pounds close to the quick attach, less the farther you get away from it. The tubing that I am using weighs about 100 pounds per 6 feet. I am using about 275 pounds of that. The cylinders, hoses, valves and seat will bring it in pretty hefty. I will probably put some sort of retractable wheels on it. Probably something that will support its weight but can be lifted off the ground with the outriggers. I really want it to be heavy, so it doesn't bounce the tractor around too much.
 
   / Build A Backhoe For PT425... It Could Happen #87  
Having a job that needs done and being able to figure out the right crutch, gadget, or fix to get the job done is not a sign of being unskilled its a sign you are having fun. There is just something about the moment when the crutch , fix, or gadget comes to your mind that is very satisfying and when the job is finished and it turned out just right it kindly makes you want to strut just a little, but when it don't work out just right well I don't talk about those too much but even that is not a total loss because you still learn something . I like the jigs you have for your plasma cutter there is a lot of good ideas there.
 
   / Build A Backhoe For PT425... It Could Happen
  • Thread Starter
#88  
<font color="blue"> after you have used the saw a little more please give us an evaluation on the saw. </font>
O.K. Here goes.
I made that first cut at a 90 degree in 4" square tubing with 1/4 inch walls. It took about 20 minutes. The ends were beautiful and looked almost machined. Smooth as can be.

So I set the saw's vice angle to 20 degrees and it took the 4" tubing no problem. Made the second cut in about 25 minutes. Probably due to more steel to cut, since it was an angle. Again, the cut is beautiful. Slow, but painless to the operator. Just sit there in a plastic lawn chair and watch it work.

Put the other half of the boom in the vice and started that cut. Again, a 20 degree cut in the 4x4 tubing. Same deal. Slow and steady... until the motor smoked! /forums/images/graemlins/tongue.gif

I shut it down and let it sit for half an hour. I attempted to start it and it made a loud clacking noise. I looked inside the housing and saw that the motor has a plastic fan on the shaft. The motor got so hot that the plastic fan melted on the shaft, then when it cooled, it stuck off center. GRRRRrrrrrr. O.K. Who's going to be the first with the "You get what you pay for?" /forums/images/graemlins/grin.gif

So today I called Harbor Freight, told them what happened, and asked for a replacement motor. They said they don't do parts, just bring in the whole saw and I could exchange it. So I loaded it up this evening, took it out there, and they had one waiting for me. The clerk said she has sold many of those saws in the five years she's been with the company and never had one returned. But, no hassle, no fuss.

Only problem is I have to assemble another one now. That takes about a half an hour. It also comes with a 24 tooth per inch blade. I bought an 18 tooth per inch blade and will try that out to see if I can get faster cuts.

When I bought the saw, they offered a one year replacement policy for $34.00. I declined it. There is a 60 day warranty. So I better get all of the pieces cut in the next two months, just in case. /forums/images/graemlins/wink.gif

I can't figure out why the motor overheated like that. As I mentioned before, there is very little down pressure on the unit. I can lift it with my pinky finger for cryin out loud. With the belt disconnected I can spin the shaft that drives the blade by hand and it coasts very easily, so no problems with the wheels, guides or gearbox. Belt was proper tension, too. Problem had to be in the motor, in my opinion.

What do you folks think?
 
   / Build A Backhoe For PT425... It Could Happen
  • Thread Starter
#89  
Picture of saw with 4x4 in vice.
 

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   / Build A Backhoe For PT425... It Could Happen #90  
Could you tell if the fan was spinning when the motor was running, prior to failure of course? It could be that the fan was slipping on the shaft. This would heat the fan up and melt it.
Pure speculation on my part.

Bob Rip
 
 
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