Dremel Shell work

I was very excited to start cleaning up those messy shell edges from the first excess material cutting and sanding session....or just excited to play with the new dremel. 

I did some reading and research on how to use the dremel, which is a good idea for anyone. Since I'm cutting up plastic, I decided to use safety glasses and a mask. 

I had to be very careful and precise about cutting with the dremel, so I didn't film the process. I ended up with lots of plastic burs to file off, lots of plastic dust all over the place and on me, and much better edges. I used some 60-100 grit sandpaper to smooth things out, and am pleased with how everything came out. There are still some edges that are too deep, but it won't be very noticeable when I paint the frame and assemble everything.

The next major steps will be cutting material out of the bottom shell for the wheels wells. 

Shocks System Modification

If you watched the short video on my last post, you may have noticed cut up plastic straws in the frame. These will be used to keep the shock system in the RC car from working, making it so the droid doesn't bounce too much. If it were to bounce like an RC car, the bottom shell would scrape the ground every time it hit a slight imperfection in the ground. Not what anyone wants. This method was recommended to me by a few other builders, though some use PVC pipes or other material.

Here's a good look at one of the straw pieces and one of  four shock absorber parts. You'll see I use different colored straws later on, because getting the measurements right took a few tries.

I thought about using my new toy/dremel to cut the straws, but the heat of the spinning blade just ended up melting the plastic...how did I not think of that? I was able to use regular scissors to cut the pieces. I also cut them lengthwise so they can be slipped over the thin metal rods.  

I had to hold the springs up and push the cut straws onto the tiny rods. These are very strong springs, so it was actually pretty hard and a bit painful. But  all four shock absorbers have a straw, so we can move on to things that won't tear up fingers. 

 

Painting More Details

On Friday, more materials for details arrived for me to paint.

The dowel will be used to make vertical details on the side of the PCB panels. I will likely glue them to something sturdy, put velcro under that, and attach it to the Mouse Droid.

These square beads will be used to give my top Greeblies height. I have craft wire I can thread through the square blocks and holes in the main top greeble piece.  Strong velcro will be used to attach it to the top of the Mouse Droid.

I did some practice with my new dremel by cutting the dowels in three 6 inch long pieces. I filmed a little video, my first time doing something like this, to show more of the process. 

Safety Note: As usual, keep yourself out of the way of the dremel. And I'd recommend ear protection depending on what you are cutting. Safety glasses are a great idea, and maybe a mask so you don't breathe in particles.

I wasn't sure how to prop the dowels up for even paint coverage, then I noticed the cardboard box has some small holes you can stick the dowels in. I painted one side, waited, and did the other side.

Here are the blocks and dowels all painted. I will let them dry for a couple days. 

Painting the PCB Boards

I painted the rest of the PCB boards with the gloss black Rustoleum spray paint, and will allow them to dry for at least a full day.

The can of spray paint said the paint should be dry to the touch after 15 minutes, so I waited for that amount of time and then placed the boards in a better spot to dry completely. 

Because I did this outside, some plant matter flying around in the breeze got stuck on the boards. I was able to scrap that off gently with the end of a paperclip without damaging the paint. The IC's should cover most of the board anyways, so a few tiny copper colored spots are not the end of the world. 

I may start adding IC's and rhinestones to these tomorrow, or use my new dremel to finish cutting and sanding the shell halves. It might be best to wait and let the paint set longer. 

Side Greeblies Design Plan

I decided to start planning how I want the side Greeblies to be. A problem came up where the two 6x6 inch PVC panels are too big for the 3x3 array of almost 2x3 inch PCB boards. There's a bit too much extra space for my liking. I may just add them on and decorate the extra space somehow, but I'm not sure. I did a weight test with the PVC panels and shell, and it seems fine. I plan to use heavy duty velcro to attach the PVC panels (and will use the velcro on other parts), so if the set up is too heavy, things can be adjusted.

For now, this is the general set up for the PCB boards on the sides of the top shell. 

 

The integrated circuits (IC's) fit well, though sometimes the feet are a little tricky to fit into the holes of the PCB board. The metal feet do bend, so they can be flattened and sit against the shell. 

This is a test layout of how the IC and rhinestones will go on the PCB boards. I might play around with the pattern a bit. I decided to order some larged IC's for variety, and because these are not as rectangular as I would have liked. The purple rhinestones are a bit lighter in shade than I expected, but I'm still happy with it. 

Eventually, all of these will be painted black. I did a one coat test of Rustoleum Ultra Cover 2x Gloss Black, and can still put the IC's into the holes. Because the IC's can be a little tricky, I'm not adding more paint because it could end up blocking the holes. 

And that's it for now. I'll have to paint the shell halves before attaching anything. 

Shell Work, plus Side Greeblies News

 In the scope of my Mouse Droid build, the most labor intensive part was always going to be cutting and sanding excess shell material. To figure out where to cut, I insert the inner frame into each shell half and mark a line inside the shell barely above the frame. 

After that, cutting and sanding tools of choice are used to make the shell edges even with the inner frame. 

To cut off the excess, I used a combination of a utility knife, a cutting tool, and a jigsaw. I made sure to cut conservatively and slowly. Taking off material is easy, but adding material back can be very difficult. The material is so thick that took all three tools and a couple hours to cut most of it off. The knife was ok, but pretty slow and less agile than the cutting tool. 

Safety Tip: I have cut myself deep enough to leave a small scar, so I would wear gloves when using knives. Even some tough gardening gloves may work in the pinch. And try to cut away from yourself, aim the knives. It's worth the extra time and effort. 

The cutting tool is actually made to cut metal, but worked here. This plastic is quite thick, so it wasn't as easy as I thought it would be.

The jigsaw worked very well (seen in the far back), but was too big to fit into some corners.

Safety Tip: Keep your hands, and generally yourself, out of the path of the jigsaw. You may want to use safety glasses when cutting to avoid fragments getting in your eyes, especially if you need to get up close and personal with your work. You may also want to wear a mask to avoid breathing in particles, especially plastic.

I did some of the edges sanding with 60 to 100 grit sandpaper, and used a block to hold it in a more comfortable position. 

Safety Tip: It may be a good idea to wear a mask when sanding plastic to avoid breathing in any dust. A glove always helps keep your hand comfortable.

The near end result looks quite messy, but I prefer a slow and steady pace. Measure more than you ever cut to avoid potentially costly mistakes. I was able to mostly use a jigsaw on the top half of the shell, which is why it looks much cleaner. A small gap between the shell halves is perfectly normal. 

More work will need to be done on this later to remove excess, high ends, and make smoother edges.  And for this task, I finally bought I tool I've been thinking about for years....a dremel kit. This will make cutting and sanding more complex parts easier and less error prone. This kit came with 15 attachments that will definitely make a difference later. 

In other news, some parts for the side Greeblies arrived today. The two dark gray PVC panels will be the main base of the details for each side. They are pretty light, though I may do a driving test to make sure it's not too heavy or anything. I will likely be attaching these with strong velcro in case I want or need to make changes later.

On top of that, about six PCB's (printed circuit boards, like breadboards) will make another layer of detail. I could not find a 6x6 inch PCB, so I bought a few that are 2x3 inches, (or 5x7 cm), and will attach them to the PVC panels with velcro in case changes are needed or wanted later.

 Next, decorative IC's (integrated circuits) will be fit into the PCB's with a special detail....

I want to give my Mouse Droid some flair and personality, and purple is my favorite color, so I went with black and purple rhinestones. I will likely glue anywhere from a dozen to 20 of these to the PCB's.

There are some small vertical side details on the Mouse Droid that are yet to come, but this is most of the material for the side Greeblies. 

Inner Frame arrives from Beren

After doing some research earlier this year, and knowing my access limits on tools, I decided to try and order an inner frame from another builder (assembled or not). I found Beren’s” build log on the Mouse Droid Builders forum, and his design was made for a Granit Earth shell, which I have. I contacted Beren, and was able to have an inner frame made and sent to me, arriving this morning. 

Beren’s inner frame is built from 1.5" x 1/2" poplar wood, and fits very snugly in the Granite Earth shell. The inner frame also has dowels for alignment. I do not currently have access to a drill press, so I knew drilling holes for dowels would be a challenge. If the alignment is not right, the frame (and shell by extension) will be offset and look wrong at best (at worst, nothing would fit together). 

I will be reviewing his and other build logs before doing any work with this frame and shell, but wanted to post an update.