JCB Backhoe Loader
After tinkering with this off and on for a year and a half I'm finally happy with my rendition of Steve Butterworth's JCB model.
I worked from Steve's CC photos and some photos of Dennis Backler's version. I seem to recall hearing that there was a writeup in CQ but I
don't subscribe. I'm sure seeing that might have helped but sometimes figuring out things on your own is half the fun.
Regards,
Wayne
As soon as I saw Steve Butterworth's little JCB model in the 2014 Christmas Challenge I decided to have a go at building it. In a surprisingly short time I had both the backhoe and loader completed. I found the little rams to be an ingenious construction. The captive rubber collars did an admirable job of holding the mechanisms in place.
I had expected to have to do a lot more "find just the right collar with just the right friction" than I ended up doing.
The cabin top went together as a separate unit and wouldn't be attached to the rest of things until the end. I noticed that Steve had redone the
cabin in one of the later photos that he'd taken and I followed that as best I could. I did a fair bit of guessing on the back side of the cabin
top as there was no photo showing any part of that.
The steering was interesting to figure out. It took me a couple of tries to figure out all the ins and outs of it. As the front end loader hangs
off the front of the steering column supports, it has to be very rigid. My first try didn't account for that and it just keeled over. Going back
to the photos, I noticed the tiniest little ridge showing through on the side of the column and realized that I'd missed a narrow 7 hole 1/4"
spaced strip on either side. They joined the top and bottom into one rigid piece.
At the bottom of the steering column axle I attached a handrail support to give me the 90 degree turn. On the end of that went a threaded boss
on to which was bolted a narrow right angle bracket. That was lowered over the top of a threaded pin which was attached to the middle of the
steering arm.
The chassis was definitely the hardest part to figure out. There was very little detail showing in any of the photos. I lost count of the
number of times I built up a chassis only to disassemble it before it was even complete. For such a small model, it's very heavy, and the
chassis has to be very rigid to accommodate the weight of both the backhoe and front end loader. All that brass adds up in a hurry!
It wasn't until I saw some pictures of Dennis Backler's version that I started to make some headway. There were a couple of shots taken without
the cabin top on that gave me some vital clues on how to proceed. A couple of long couplers mounted on the rear of the chassis were the
starting point for a rigid mounting point for the chassis floor. There were still long periods of sitting and staring at the model wondering
"well, NOW what?" but eventually things started to come together.
The last piece to fall into place was how to attach the front end of the motor compartment to the chassis. The back end was attached to the top
of the steering column with an axle but without something to hold the front end down, moving the loader pulled the motor compartment up with
it.
Since I hadn't used the 2 x 3 hole angle girders that Steve had used to form the front of the motor compartment (I used a 1" by 1-1/2" flanged
plate) I had to come up with my own attachment mechanism. The flanged plate was a little narrower than the angle girders would have been and
wouldn't accommodate the 1" double angle strip that I suspect was originally used. In the end, I bolted a narrow angle bracket (C330) to
the chassis bottom and slid a 1" triflat axle through it and the lower end of the flanged plate. The two decorative 1" x 1/2" yellow 12b angle
brackets on the bottom front of the motor compartment ended up serving a practical purpose by preventing the 1" axle from sliding out.
don't subscribe. I'm sure seeing that might have helped but sometimes figuring out things on your own is half the fun.
Regards,
Wayne
As soon as I saw Steve Butterworth's little JCB model in the 2014 Christmas Challenge I decided to have a go at building it. In a surprisingly short time I had both the backhoe and loader completed. I found the little rams to be an ingenious construction. The captive rubber collars did an admirable job of holding the mechanisms in place.
I had expected to have to do a lot more "find just the right collar with just the right friction" than I ended up doing.
The cabin top went together as a separate unit and wouldn't be attached to the rest of things until the end. I noticed that Steve had redone the
cabin in one of the later photos that he'd taken and I followed that as best I could. I did a fair bit of guessing on the back side of the cabin
top as there was no photo showing any part of that.
The steering was interesting to figure out. It took me a couple of tries to figure out all the ins and outs of it. As the front end loader hangs
off the front of the steering column supports, it has to be very rigid. My first try didn't account for that and it just keeled over. Going back
to the photos, I noticed the tiniest little ridge showing through on the side of the column and realized that I'd missed a narrow 7 hole 1/4"
spaced strip on either side. They joined the top and bottom into one rigid piece.
At the bottom of the steering column axle I attached a handrail support to give me the 90 degree turn. On the end of that went a threaded boss
on to which was bolted a narrow right angle bracket. That was lowered over the top of a threaded pin which was attached to the middle of the
steering arm.
The chassis was definitely the hardest part to figure out. There was very little detail showing in any of the photos. I lost count of the
number of times I built up a chassis only to disassemble it before it was even complete. For such a small model, it's very heavy, and the
chassis has to be very rigid to accommodate the weight of both the backhoe and front end loader. All that brass adds up in a hurry!
It wasn't until I saw some pictures of Dennis Backler's version that I started to make some headway. There were a couple of shots taken without
the cabin top on that gave me some vital clues on how to proceed. A couple of long couplers mounted on the rear of the chassis were the
starting point for a rigid mounting point for the chassis floor. There were still long periods of sitting and staring at the model wondering
"well, NOW what?" but eventually things started to come together.
The last piece to fall into place was how to attach the front end of the motor compartment to the chassis. The back end was attached to the top
of the steering column with an axle but without something to hold the front end down, moving the loader pulled the motor compartment up with
it.
Since I hadn't used the 2 x 3 hole angle girders that Steve had used to form the front of the motor compartment (I used a 1" by 1-1/2" flanged
plate) I had to come up with my own attachment mechanism. The flanged plate was a little narrower than the angle girders would have been and
wouldn't accommodate the 1" double angle strip that I suspect was originally used. In the end, I bolted a narrow angle bracket (C330) to
the chassis bottom and slid a 1" triflat axle through it and the lower end of the flanged plate. The two decorative 1" x 1/2" yellow 12b angle
brackets on the bottom front of the motor compartment ended up serving a practical purpose by preventing the 1" axle from sliding out.
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Wayne Hortensius - Calgary, Alberta
