Thu Feb 11 2010

Fabricating latching mechanism

After giving a lot of thought about how to secure the forward end of the center support, I decided a through pin latch mechanism would be best. I had been planning on just using a Dzus fastener (1/4 turn style), but those are not suitable for any significant tension loads. That fact in combination with the thought that I'm going to need to put Snickers in a harness and secure him to the platform (both to keep him from underfoot as well as keep him from flying around during turbulence) made me decide to go with a more robust forward attachment. Here are a few of the pieces. The spring was $0.69 and the roll pin was $0.29 at Ace Hardware. First task is to cross drill the stainless steel pin for the roll pin.

In an attempt to drill as on-center as possible, I decided to make a drilling jig out of a scrap aluminum block. First task was to drill a #30 pilot hole long-wise through the block. Note which side of the block is against the green clamp block.

Then rotating the aluminum piece 90 degrees while keeping the same side against the green block allows me to drill a cross hole that precisely intersects the first hole.

Afterwards, I opened up the long hole to 1/4 inch.

The pin was a slight press fit with the block so I just pounded it in until the drilling location was positioned under my pilot hole, then drilled 'er through.

It came out pretty good. The hole is a few thousandths off center, but it's good enough for what I'm going to use it for.

Here's a photo showing a preview of how the latch mechanism will be coming together. It was tricky getting all three angle brackets drilled so the holes are exactly aligned.