Yesterday was a big day in the workshop with continuing progress being made on the Captain America ball chair project. I wanted to get this post out before the weekend so that I could do a little traveling to see my son and his wife who live some distance from me. So this will be good for you as well as for me this weekend.
In my last posting I had just completed the process of removing the dish shaped part for the upper base assembly from the dome for the ball section of the chair. In this photo is the completed dish after it had been clean of any miscellaneous tape from the first part of the build and an additional layer of eight ounce cloth was then added to the top surface. Once this had cured I trimmed off the excess to the correct size that is needed for the base upper assembly.
Here is a good look at the base upper assembly that the dish will be added to. Once this done it will have a total of ten combined parts that will all be fiberglassed together to make up the mounting for the ball section of the chair.
I took the dish part and laid it upside down on my work table so that addition fiberglass could be applied to both sides of the slot that I had cut into the part. Cutting this slot worked out much easier than I had hoped. I was originally going to use a carbon fiber disk in my Dremel tool to cut the slot but when I did the disk exploded into a lot of little pieces. I suspect that the disk was old and worn out that was the cause of the failure.
I then picked up another tool that I have here in the shop called a Sonicrafter from the Rockwell company. This is a tool that has a wide variety of blades that vibrate when they cut. You can touch the blade to your hand and it won't cut you but when you touch it to a part it will. It cut through this fiberglass part like a hot knife through butter. Worked great! I marked the slot first with a Sharpie and then drilled a couple of holes to get the ends of the slot looking good. Then it was just a matter of a couple of minutes to cut the slot out using the Sonicrafter.
I then took the dish and laid it upside done on my work table again so that I could epoxy it to the upper base mount assembly. Using fiberglass resin and a micro-balloon mixture to bond these part together. I placed several pieces of wood, foam, and a bucket of plaster on top of the assembly to weight it down until it had cured over night.
Here is what the finished assembly now looks like after it had dried. I've always said that you have to make something look ugly before it can become pretty in the shop. This is no exception with this assembly. Actually though I am very pleased with how this part turned out. It is fully fiberglassed now and only need the finishing work and a little paint to make it look pretty. Even with saying that very little needs to be done with the part as most of this assembly will be hidden once the ball chair is completed and assembled to the base. So I don't have a lot to do yet to finish this part of the project.
The next step in the project was to continue the assembly of the lower base unit. I had finished fiberglassing the blue part that is shown in the photo above and bonded the two pink rings to the assembly using fiberglass resin and micro-balloons once again. This portion of the build then needed to be fiberglassed on the inside of the rings to seal it completely.
Next I took the leg support parts along with additional spacers and hot glued them into place on the under side of the base unit. This went very quickly and will give the base for the chair a very solid platform to hold the upper base assembly and the ball section of the chair when it is completed.
Here I started to apply the 1/4 inch foam strips to the outside of the now upright base assembly. I had completed puttying the joints of the leg supports both above and below the now center blue disk that you see in the photo above. This added much more strength to the assembly. The foam strips like the ball section of the chair were applied using a hot glue gun. It's time consuming but not difficult work to get a good shape for the fiberglassing that will be done later on.
Here all of the strips for the lower base section of the chair have been applied to the framework. It already has a very nice shape and very little has to be done to get a nice smooth surface ready for fiberglass.
I took the lower base assembly this morning and laid it on it's side so that more fiber glass resin putty could be applied to the joints that mate up to the new outer skin. Once this has cured I will fiberglass the inside of this cavity wherever it is needed before finally sanding of the outside foam to prep it for several layers of fiberglass.
The last thing I did was set up this pink part at the foot of the lower base assembly. The blue foam will be cut out of the assembly at the archway shaped section of the pink part so that and opening will be built to allow electrical power to be fed into the chair for the lights and sound system that I have planned.
All in all I managed to get a lot done in the last seven or eight hours with the project so I will be more than happy to leave it sit for another couple of days while I am on the road visiting my son. With this portion of the build nearing completion the lower base assemblies look to be just what is needed for the ball chair project. Coming right along just as I had planned so it makes it another good day in the workshop. Total hours on the build now stand at 65.5 hours. Enjoy the photos and the weekend.