Bob looks as tho she thinks she could have done it better.
I get the impression that both of them think they could do a better job but since they're cats it would be just to un-cool for them to try.
Since my previous tries at a mechanical lifter for the Back Platform didn't work out I'm moving to a second actuator. A design where the actuator was mounted directly below and parallel to the Seat Platform would have been nice but I was worried about the strain that would put on the hinges joining the two platforms. Especially in the first few degrees of lift. So with some help from Sgt. Wookie at the AllAboutCircuits forum I came up with this design.
The Metal Angle is used to join the Plywood Rectangle to the Seat Platform. The Plywood has the Metal Supports bolted to it. On the end of the Metal Supports the Actuator is mounted and allowed to pivot. Not shown in the drawing is the Back Platform which is hinged to the Seat Platform and raised and lowered by the Actuator.
First step is to cut out the Plywood Rectangle then drill holes through it and the Metal Angle. I'll use bolts to join the two.
I hadn't yet received my new center punch so was still using a nail to indent the angle.
If you take your time as you drill through the aluminum angle you can play the "See how long of a metal shaving I can make" game. Here's my entry at over 4 inches.
With the Metal Angle bolted to the Plywood rectangle start to construct the Metal Supports for the Actuator.
I had previously purchased a length of 1" wide by 3/16" thick steel stock to be used for the construction of the mechanical lifter. I'll use that for the Metal Support. I didn't have enough unused stock so I'll use reuse one of the lifter pieces. It's not as long as I'd like but I'm sure it will suffice.
The pivot hole on the base of the Actuator is 1/4" wide which is the same size as the hole already in the reused piece. Problem is the two holes don't line up so a little grinding needed.
Have to drill a hole in the other piece of stock for the pivot point. Will need both pieces of metal stock that will comprise the Metal Support to stay together so the pivot hole and the other holes I'll be drilling for the bolts all line up.
Clamp the two pieces together.
Then clamp them to the drill press -
and oh so carefully line up the drill bit with the previous hole.
Then start drilling all the holes I need. Moving the metal stock as needed.
When I'm drilling through steel I use 3-in-1 oil as a cutting oil. You can buy true cutting oils but this works for me. The purpose of cutting oil is to reduce the heat on the bit and help remove debris from the cutting edge.
It does make things a bit messier but you can actually feel the difference the oil makes via the capstan wheel. The capstan wheel is the three spoked handle on the side of the drill press that you rotate to raise or lower the drill bit. When I lower the drill bit onto the metal stock it first feels like it's "skating" but after adding the oil the bit seems to "bite" more. It's almost counterintuitive since oil is a lubricate but hey, it works.
After drill all the holes I cut and filed these grooves in the pivot end of the Metal Supports. The grooves function is to allow the actuator end to pivot.
Figure out where to place the one of the Metal Supports on the plywood then clamp into place. Next drill holes through the wood.
WARNING: THIS IS WHY YOU SHOULD ALWAYS WEAR EYE PROTECTION!
As I was drilling through the wood the drill bit caught on the edge of the metal stock and without warning snapped right off.
As you can see from this photo the edge of the broken bit is wickedly sharp. Imagine a piece of that flying into your eye. And yes it can happen. I've seen the after effects in person.
Without further incident, and a new drill bit, finish with the holes through the wood. Then bolt the Metal Support pieces to both sides of the Plywood.
Since the base of the Actuator at the pivot point is wider than the thickness of the Plywood I used a couple of washers to spread apart the Metal Supports at the pivot end.
Attach the Actuator with a locking pin (I've recently found out they are also called "detent pins") and check that it is able to freely pivot.
I could lie and write that I got it right the first time but no. There was much fitting and filing before I got it how I wanted it.
This is all the movement that I needed.
Poor Tiger. Supervising me from the top of the basement stairs is such hard work, NOT.