Monday, February 8, 2016
So the sleeper cab started it all. It came out how I wanted it. The requirement that I has was the sleeper door had to open. Hardest part of the design was figuring out how the door would stop and not swing both ways. It honestly took me a long time and several iterations to move the back in 3/8" to use the back of the cab as a stop. Sometimes the simple answers are the easiest and most often overlooked. The overall design follows closely to the other cab design just longer. I have made a few of these so it was not too bad of a build.
The carrier was a little different story for the design and build. I wanted it to be able to move and I had a vision of what parts should move and how. I wanted the little ramps to move and I wanted the back section of the upper ramp to lower down. the thought of having the entire upper section rotate 90 degrees down felt like cheating to me. I also wanted the posts to be able to support the upper section without being reinforced. Some of these presented challenges others were abandoned.
Having the back section move up and down was a challenge, but after designing the front end loader, I had some pretty good ideas. Making sure the parts had enough of a radius became the hardest part. However, I did learn that I do not have to radius everything. There is a block that I originally had a radius that proves to weaken the dowel joint. If I take off the radius it is fine.
The ramps were relatively easy to do however it did take a little bit of had work and a rasp so that they would move up and down. I was a little worried about the cutout in the raising and lowering arm. It is stronger than it looks because it is all in line with the grain.
Now there were some compromises that were made with the design. I figured if I angled the support rails in such a way I would only need two pegs per support rod to keep the upper level ridged. That did not work out. There are two support rods that have three pegs in it. It does not detract from the look at all.
The other design feature that I missed was the grooves in the rails where the tires roll on. The original design called for 5/8" deep by 7/16" wide. I had a 3/8" rabbeting bit for my router. To make the groove that I wanted, I would need to buy a new nonstandard bit. I am all about finding a reason purchase new stuff, but I need to be able to design for common tools. It was a good and quick change in the design.
I posted this to facebook to get feed back on the design and I received a lot of good comments and I would like to address some of them. There was an overwhelming response that the wheels on the trailer need to be larger. I tried putting it in the design and it moved things too much. I could go to two larger wheels instead of three. I am still mulling through the wheel design. I also received a lot of comments that the support rails looked like popsicle sticks. I can make them square without a problem. The last comment was having the trailer over hand the cab and adding another car. I ran with this idea for a little while. Then I watched my kids play with their toys and realized they use the cab to push the trailer around. If the trailer was overhanging the cab, it would get in the way of the kid pushing the toy. I have shortened the chassis of the cab so the trailer is closer to the cab so it doesn't look so distant.
It was a lot of fun to build. I hope my kids enjoy it as much I did building it.