Sometimes, you want to finish something as quickly as possible. You desperately want to make progress, feel the urge to get back to it continuously and yet you can’t find any time to do just that. You just can’t, and every step takes forever as a result. That pretty much sums up the situation I’m in right now with this project.

Anyhow, as you can see I finally did manage to take the next step by finishing another important part of the tool – the business end! It’s a very detailed piece that consists of four separate parts right now (I’m not sure yet how I’m going to mold it though). And four very tiny parts I might add. The smallest one is only 5 mm in width!

This is by the way the part of the probe that was originally made from a disassembled nose hair trimmer. Unfortunately, despite my best efforts I wasn’t able to identify the exact model or even manufacturer of that trimmer, so I couldn’t use the original and had to scratch-build something instead. It was one hell of a lot of tedious work, but – to be honest – the result is probably nicer and cleaner than any found item, which makes the whole thing worthwhile in my book.

But, judge for yourself. To refresh your memory, here’s the front part of the original prop as well as the schematics I did as preparation for this project:

And here are the pictures of my finished multi-part piece:

So, let’s get down to business. How did I create these parts? Here we go:

It all started with some more or less precisely cut pieces of styrene, my material of choice when it comes to scratch-building stuff.

They would make up the body of the largest piece. Which is round. Which meant that I had to sculpt it somehow since I didn’t have anything that I could’ve used as a base piece.

So I marked an appropriate line for the outer curvature on all pieces and cut them with an X-acto knife.

As you can see, I also cut some material away at the top to make it easier to create a recession there later.

Then I arranged them in a circular way to build a kind of skeleton structure and glued them together using plastic glue.

The next step was to fill the spaces between the “ribs” with putty to “put some meat on the bones” as it were.

Then the sanding began. Oh, boy. The sanding – that’s the kind of work that I’d like to have an assistant do for me or something. On the other hand it gives you great control over the final shape of your piece. The downside is that it takes a long time. A very long time. And especially so if you’re only one bit as anal about a perfect surface as I am…

While sanding the outer surface of this part I also paid some attention to the top side of it where I needed to have a pretty substantial indentation with a thin lip around it. To achieve this I used a mini-dremel with an appropriate attachment to remove material from both the surface inside as well as the “walls”.

Here is an intermediary result. Looks pretty nice already, doesn’t it?

On to the next part, which is essentially the same deal as the first one, except smaller and with a more straight profile. And when I say smaller I mean like 9,5 mm tall! That’s pretty tough to even hold in your hands (depending on what kind of hands you have of course). But holding it while trying to leave some room for sandpaper to work on it? Yep, you guessed it – that’s not easy to say the least. To illustrate: I even had to use tweezers to glue the “styrene skeleton” parts in place, which were only a couple of millimeters in width.

Here’s another preliminary result, this time a bit smoother. As you can see, I used spot putty on the smaller piece to fill in tiny holes and gaps.

And this is where Murphy came into play. It turned out that I had miscalculated something or simply had visually misjudged the proportions of this small piece. Anyway, it was evident that it was too thin and I had to somehow make it thicker – or wider if you look at it from the side.

Sounds easy, but how should I do that? Well, after thinking about it for a bit I decided to simply add material by gluing small strips of styrene to the side of it and fill it with putty as before. Yay, more sanding! Not exactly what I wanted to do but it sure did the trick:

After that small setback, I moved on to the next part, which is a kind of add-on to the first, “big” base piece. I made it basically from four small strips of styrene, which I glued together and sanded in shape.

A little putty to hide the seams:

A little sanding – done.

So, here are all of the three pieces that had been done at that point:

Next, I had to make the small, narrow part fit into the bigger base. So, I cut a piece out of the side of it and added some putty back in to make the new surface nice and smooth. Again, I used my mini-dremel to do that, this time with a small circular saw attached to it. I also used various small files to work on that slot.

While working on any of these pieces, by the way, I sprayed light coats of automotive primer on them all the time to reveal small blemishes, scratches or any kind of unevenness that needed to be fixed.

It wasn’t until I had created this slot that I noticed how deep I had carved the indentation into that big piece from above. Clearly too much! When put together, the final element of the prop would not have looked very good like that. So I had no choice but to improvise again and insert a round piece of styrene to raise the level of that surface a bit. This of course meant that I also had to putty it to blend it to the “walls” inside:

A lot of sanding later – and I mean a LOT of sanding later – the mistake was corrected and the surface both inside and outside was smooth as an androids butt. Also, the small add-on piece fit in its place perfectly.

To finish this piece off I had only one thing left to do and that was to create tiny grooves on the outside as a bit of detailing to give it some structure and make it interesting, not to mention match it with the original of course! To do that I cut tiny pieces of tape and put them on where I wanted the grooves to be.

Then I applied several coats of primer to add some material to the outside.

Then I removed the tape and voilà – micro-detailing!

Last but not least I had to tackle the emitter tip, which proved to be extra challenging. What I needed was a very small piece with very specific measurements and three tiny rings around it. At first I had no idea how to achieve this, but then decided to try to sculpt the tip from air curing clay which worked out quite well.

The three rings around the tip gave me a headache though. How the hell should I sculpt those by hand? It seemed impossible. Then I had the idea to wrap a bit of wire around it to at least get an approximation of what I wanted. It would be a short spiral instead of three separate rings, but that was the best I could think of. And it turned out that it worked really well and looks very nice even if it’s not perfect. After all, it’s only a very small part of the final prop…

So, here’s the final result again:

Note that I added a small indentation on top of the middle sized piece as well, similar to the one on the big base piece to create a small lip and a place for the emitter tip to fit in.

Seeing those four parts together now that they’re finished, I’m very satisfied with this part of the probe and I think it goes very well with the main parts I did a while back:

I’m sure it’ll be a great prop when it’s all done. And I sure hope that I’ll be able to make some more progress in the near future, too!

What do you think? The good, the bad and the ugly – I’d love to hear back from you in any case, either via a comment below or via eMail!

Also, if you want to watch my prop-related activities more closely you should follow me on Twitter. Every time I’m in my workshop, you’ll know it instantly and see what I’m doing in real-time before anyone else can read about it here on the blog. Sounds like something you might enjoy? Follow me @trekprops and get the inside scoop!

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Modulor direct link: Proxxon model building and engraving set (#153186)

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Matt’s PADD kits contain three black acrylic plates which have been precision cut with a laser using the accurate shapes traced from an original prop. The thickness of the plates is also correct (3 mm).

Along with these plates I got a set of graphics for the display and the control buttons. I also got another display graphic so I could choose my favorite one. Furthermore, there’s a sticker of brushed aluminum vinyl included for the big button in the right control window. Looks sweet!

Here are all of the kit pieces at a glance:

There is a protective paper backing on the acrylic plates. This is a necessary part of the laser cutting process.

This paper has to be removed first, but only on the “inner” sides of the front and back plate:

These are the two plates without the paper. Note that the right (front) plate is lying on the table reversed showing it’s “inner” side.

Next these plates are carefully glued together so that they are perfectly aligned to each other and the edges are flush. This is just a temporary fixation and will be unfixed later. So I didn’t use a non-removable glue, but double sided adhesive tape instead.

I left the paper attached to the front and back side to protect them during the next step.

The corners and edges of the PADD need to be rounded. Since acrylic is a pretty hard material, you won’t have much success using sandpaper. For this you need either a dremel with an appropriate attachment, a router or a big file. I decided to use the latter to keep a higher degree of manual control.

This is a rather tricky process. The curvature should be clearly visible, but it shouldn’t be too round. It wasn’t easy to remove an equal amount of material all around and on each side to make it look symmetrical.

The file work is of course only a means to add the bevel to the plates. You won’t be able to get the surface smooth that way. To achieve that, I used sandpaper going from lower to higher grit numbers. This works best using wet sandpaper under running water!

During sanding I then disassembled the two plates to also sand the “inner” edges slightly – not to round them, but to remove flashes left over from the laser cutting process.

Finally, I also removed the paper backing to check the curvature of the two plates and used sandpaper to do corrections.

Here’s the result of my work with file and sandpaper:

Next up is priming the PADD.

Since the plates are later glued together, the areas where the glue will be applied need to be masked. This is done because glue attaches itself more easily to “naked” acrylic than to primer or paint. This way you won’t have to use sandpaper later to rough up the surface.

To prime the pieces, I placed them on paper without suspending them in any way! This way I didn’t have to worry about overspray getting on the other side of the plates and making them look ugly. I didn’t prime the edges in this step because they could get stuck to the paper.

When the primer was dry, I turned the plates over and then did suspend them on small blocks of wood. I primered the pieces again and also applied some to the edges. Because the plates are suspended, they can’t get stuck to the paper and I don’t have to worry about overspray because most parts of the inner side will not be visible.

I repeated this step with my Plasti-kote 7173 equivalent spray paint,  suspending the pieces when doing the outsides and laying them flat when doing the inner sides.

Next up are the graphics. They have to be cut precisely to fit inside the windows of the front plate. This requires some patience.

Also the brushed aluminum vinyl sticker has to be applied to the gray area on the bigger control graphics using a pair of tweezers. The sticker has the exact same size as the rectangle and is not removable, so I had to be very precise!

Once the paint has dried, …

… I removed the tape from the inner side of the plates.

Now all the parts have to be assembled. I used 5-minute epoxy glue to join the acrylic plates together permanently. Be careful with this stuff and always wear gloves to avoid glueing your fingers together!

First, I removed the paper from the middle plate. No additional work is necessary on this one. Then, I glued it onto the back plate like so:

I had to be careful to align the smaller plate correctly (the shape is not symmetrical) and to place is exactly in the middle of the back plate. I used the working time of the 5-minute epoxy glue to correct any errors.

Next up is the front plate which is glued onto the middle plate. Again, careful aligning of the edges is in order.

The last step is to apply the graphics. They are self-adhesive so you merely have to peel them off and place them where they belong:

That’s it, the PADD is finished!

Bottom line: A very inexpensive prop that is quickly and easily built and looks just plain cool lying on a desk!

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The kit consists of the resin cast body and some tape which is added in the end. And that’s all there is to it, really.

Here are some detail shots of the casting:

And here is a picture of the original for comparison:

When I first tried to cast this prop up, I had a lot of trouble with air bubbles in my castings. Then I learned how to improve my technique of mixing the two resin components by adding them together and then pouring them from one cup to another several times instead of stirring them. So, very few air bubbles were left to be filled.

To fill the bigger holes I used a two-component polyester putty which is normally used in the automotive sector. It cures very quickly (within 30 minutes) and can be sanded very easily.

Here are two of the biggest bubbles already filled:

Next is sanding. This is the most elaborate step in any prop building project. You will spend a lot of time grinding and sanding. So, sandpaper is essential here.

Remember to “go through the grits”. This means that you should start with a higher grit sandpaper to roughly shape the object and then move to lower grit numbers to make the surface smooth. Be careful not to remove too much material in the beginning, because it’s much easier to remove a little more instead of adding something.

In the next picture you can see that I used a high-grit sandpaper to process the larger air bubbles first. The hole is still visible. Also, there is still putty which doesn’t belong there.

The tip of the instrument is next: Here I also filled a smaller air bubble and sanded it smooth going from high to low grit numbers.

I decided to drill a hole into the tip, because that’s how it is on my original aluminum prop. Also, it adds a lot of authenticity.

Sandpaper is not only used to sand down any left over putty, it is also necessary to remove other flaws that resin castings might have, for example the seam line. It occurs along the body where the two mold halves meet and is inevitable. Certain professional casting techniques however can reduce the seam line to an extent where it’s almost not visible anymore.

Reality is, that you should inspect every square centimetre or even millimetre of your prop and process it with sandpaper or putty. Sometimes however, sandpaper is not the first choice, for example when it comes to fine details or structures. In this case you should have several different small files handy to handle that.

For bigger kits or larger areas you can also use power tools like a belt sander. But be careful: These tools don’t allow the same control over your work as a manual job does. Before you know it, your project could be ruined because you removed too much material or you slipped and damaged something. Also, the risk of injuring yourself is a lot higher, so take the appropriate steps to protect yourself!

Now, if you think that the prop surface is smooth and you repaired all of the defects, apply the splash-coat (a coat of primer) to reveal any previously invisible imperfections: scratches, blemishes, pinholes.

Allright, there’s still a lot to do here!

To remove such small defects, I use a spot putty. It’s not necessary to mix it from two components which makes it very easy to use right out of the tube. I chose to use a red spot putty because it’s easily visible during the application as well as during sanding. Since it will be painted over later anyway, it won’t affect the final finish.

Here you can see the areas covered with spot putty:

After I had applied spot putty to every visible scratch, pinhole etc., I then again used sandpaper to once more remove any excess putty by “going through the grits” until the beige color of the resin becomes barely visible again. However, don’t take off too much – you don’t want to change the overall shape of the prop.

This is how the result looked like:

Now, another coat of primer was in order. After it had dried, I again took a hard look at every part of the prop. Normally there are still pinholes etc. left after this “second splash-coat”.

This is repeated until the prop body is absolutely perfect. Of course, the term “perfect” depends on what the person who is building the prop is regarding acceptable. Me, I’m a perfectionist and I probably do this way too often. Remember: The final coat of paint doesn’t hide any defects, but makes them even more visible!

A very important aspect here is patience. It can be quite unnerving to apply another coat of primer only to discover that there are still scratches or pinholes left. However, once they are all repaired, you can tap yourself on the shoulder knowing that you did everything possible to make the prop perfect.

Now that the surface was completely flawless, I could apply the final coat of primer. One last checking look: Is there still a… No, thank god it’s just a shadow!

After the primer had completely dried, I moved on to the paint. I used a chrome paint containing real aluminum particles to create a highly realistic approximation. Silver spray paint is also suitable for this. A little trick helps to prevent ugly paint blobs: Place the can in warm water for ten minutes. The heated paint will then be dispersed a lot finer.

One precept of painting is to apply several thin coats and let them dry before applying the next instead of spraying one thick coat. It’s alright if the primer is still visible after the first coat! Be patient, even if you want to finish the prop soon. You don’t want to ruin it during the last step by causing “paint noses” occurring due to too much paint, do you?

Once the painting process was finished and the paint was dry (again, you should rather wait a little long than ruining the prop), I could add the greeblies which was the last step in this buildup.

In this case, the greeblies are nothing more than differently colored grip tape cut to shape and attached at the correct areas (see illustration).

The last step is to paint the tip golden. Of course, I had to mask off the rest of the prop to protect it. I used crepe tape for this because it can be removed easily. Anyway, to avoid any risk of damaging the base paint, I only masked a small area at the tip and wrapped a paper napkin around the rest of the prop.

The prop is finally finished! Here’s how the result looks like:

Here are some comparison shots I did with the original aluminum version which served as a master model here:

There’s almost no difference visible on the pictures. The chrome paint is not quite as shiny as the real aluminum, but that was to be expected. Unfortunately it also tends to get even duller when handled.

Anyway, I think the result is very good and satisfying.

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