that's almost $700 in dog money

I built some dog wheels for Tommy; here he is pictured using them for the first time (see the video). This was my first tube project, and aside from the ten visits to the hardware store, it was fun. 1/2 inch copper, epoxy, a rivet gun, and two huge 3/4 inch diameter bolts as wheel axels.

The core of the idea is the bottoms-up leash. This leash normally slips around each leg, but while I provide the required stability for the dog. I also set his pace and direction for 30 minutes. It was tiring. While I was walking the dog I would think about how much better things would be if this leash could hold itself up with wheels.

The wheels are from Harbor Freight Tools. This was the most costly item at $50 for a welding cart from which I removed the wheels. The wheels are each running on a 3/4 x 8 inch bolt with a nylon lock nut. And 3/4 copper-T fittings on either side of the wheel join this to the frame. Finally, bushings and washers make everything fit and functional.

The copper tube is regular 1/2 inch hard water pipe, with one piece of soft pipe arched over his shoulders. The dog is about 50 lbs and so I used two supports down to the inside of each wheel and one additional support to the outside of each wheel. It took some testing to fit the height and length to the owner and so I assembled and made test fittings using duct-tape for some temporary measurements. Final assembly used epoxy and rivets to hold the glue. I left sub-assemblies to cure and set overnight.

To secure the frame to the pooch there is an important chest strap. I used foam pipe insulation add comfort padding in a few places. And lastly we used dog booties and elastic to hold his back feet up.

After a few weeks of use, I think it might need a parking break... How would you improve it?