Exploring the inside of the Rangefinder (possible found part alert!)

Very cool!

Intersesting with the LEDs. I assumed the line you are referring to that possibly shows a join between two pieces of the lens block was a scribe line. When making my lens blocks from Perspex I scribe all around before cutting and this line is left as an artifact.

Great catch.

Very interesting! You could also try a search for "grain of rice" bulbs. Pretty much the same thing.
I know that these small bulbs used to be used very often in model railroading. Not sure if they've
been replaced with LEDs in modern usage.
I also know that the grain of rice bulbs (and possibly the grain of wheat bulbs) were available in
different colors. Maybe the top 2 red ones were actually these types of bulbs also.

You've done it again Raf! Awesome discovery

WOW. I feel like I kinda had a part in instigating this. Amazing amount of attention to detail in your research Raf. Where would we be without all the info you have shared? Thank you for doing the work to make our costumes more accurate.

Great work!
You really do have this research thing down.

The first post was updated with the following additional infos and images:

Added more reference images to sustain the 2 piece perspex block theory.
Replaced the ESB/ROTJ comparison image of the perspex block side view and also added the 2mm and 1mm light bulbs.
Added a short history about the WoG light bulbs (with links) and some info at the end of the first post.

Originally Posted by locitus

Very cool!

Thanks!

Originally Posted by terminal fettler

Intersesting with the LEDs. I assumed the line you are referring to that possibly shows a join between two pieces of the lens block was a scribe line. When making my lens blocks from Perspex I scribe all around before cutting and this line is left as an artifact.

That might be possible, but looking at the C-IV hi-res images (made by Britt Dietz and Jose Salcedo) in the Gallery it looks like made of 2 parts:



The triangle part on the bottom looks dirtier and out of place than the main perspex body. Whatever method was used, these parts originally were hidden by the rangefinder casing.

And because you do these perspex blocks, I was thinking of you regarding some tests (if you have the time and/or you are willing to do it) to see the exact position (at the beginning, the middle or the end of the channels) and the light power emitted by these GoW light bulbs.

Originally Posted by SPY007

Great catch.

Thanks a lot!

Originally Posted by superjedi

Very interesting! You could also try a search for "grain of rice" bulbs. Pretty much the same thing.
I know that these small bulbs used to be used very often in model railroading. Not sure if they've
been replaced with LEDs in modern usage.
I also know that the grain of rice bulbs (and possibly the grain of wheat bulbs) were available in
different colors. Maybe the top 2 red ones were actually these types of bulbs also.

The main term is 'Grain of Wheat' and if you search eBay, you'll fine lots of these types in different sizes and specific volt/watt. The top red lamps looks LEDs to me, but might be GoWs as well.

Originally Posted by Darth Voorhees

You've done it again Raf! Awesome discovery

Thanks! You are too kind!

Originally Posted by sgtski

WOW. I feel like I kinda had a part in instigating this. Amazing amount of attention to detail in your research Raf. Where would we be without all the info you have shared? Thank you for doing the work to make our costumes more accurate.

Thanks! Yeah, sometimes this type of replying gives me the hunger to research some parts and often realize that some of the facts as I/we knew were different or wrongly attributed. But we are all humans (don't we?) and we are subjects to mistakes.

Originally Posted by kbrosseau

Great work!
You really do have this research thing down.

Thanks a lot! I guess I have some...

OK I'm seeing the two separate sections of the lens block from your reference pictures. I have Perspex to hand so let me make a piece to see how this looks.

Originally Posted by terminal fettler

OK I'm seeing the two separate sections of the lens block from your reference pictures. I have Perspex to hand so let me make a piece to see how this looks.

That's great! Can't wait to see the end result.

Originally Posted by RafalFett

Thanks! Yeah, sometimes this type of replying gives me the hunger to research some parts and often realize that some of the facts as I/we knew were different or wrongly attributed. But we are all humans (don't we?) and we are subjects to mistakes.

I don't think of them as mistakes. Finding the origins of these tiny details is extremely tough and above my skill level. I think of it more as an evolution. The more you/we find, the more mysteries we will uncover.

You're a genius captain!

Originally Posted by sgtski

I don't think of them as mistakes. Finding the origins of these tiny details is extremely tough and above my skill level. I think of it more as an evolution.

Well sometimes a mistake will lead you in another good direction; in my case: the 4th shin tool, where I thought that this tool was a hand telescope's casing, but at least I did some measurements of the 4th tool and the telescope (after I bought one), which was used as the Supertrooper/Pre-Pro/Promo sling gun barrel.

Originally Posted by sgtski

The more you/we find, the more mysteries we will uncover.

But sadly the mystery of Boba Fett will go too...

Originally Posted by Jayvee

You're a genius captain!

He he (how fast I'm upgraded and downgraded with these ranks... the last time I was some kind of Amiral?) Thanks for the kind words!

That was quick, TF!

Originally Posted by locitus

That was quick, TF!

Any excuse for a fettle in the workshop.
As luck would have it I have been working on some new lens blocks anyway.

I'm waiting on a new milling vice so will be adding the three correct holes soon...It will be good to add some of those lamps and see how the lens block looks.

Good job Rafalfett...

Updated the end of the first post with 2 images regarding the working red LEDs on most of the helmets and some partial view of the perspex block's light.

Amazing info Rafalfett, as always!!!!!!!! Thank you so much!!!!!!

Leo

Now I'm a bit dense but am I correct in the understanding here that the perspex block itself is supposed to be internally lit up by the GoW lights?

Originally Posted by Boba Leo

Amazing info Rafalfett, as always!!!!!!!! Thank you so much!!!!!!

Leo

Thanks a lot! FR accepted!

Originally Posted by Wolfsburg

Now I'm a bit dense but am I correct in the understanding here that the perspex block itself is supposed to be internally lit up by the GoW lights?

Yes, that's the whole idea, but it seems that not the whole perspex block was lit, just the 3 channels; this effect was achieved by restraining the glow power of the GoW lamps (higher voltage lamps are used with lower voltage batteries; ex: 12v lamp with 4X1.5v batteries) and also increasing the life of the bulb.

That really is amazing. Certainly would be an interesting bit of functionality for future helmet builds!

Here is an example of a 3mm diameter/6mm long 6V GoW bulb (note the different form of the bulb) with full glow running at 6V:


... and a pale glow at 2V:

Just ordered some of these bulbs to do a test. Also, from your pic of the ESB RF top that's partly hanging out, Rafalfett, it looks like there is a 1mm or so section of aluminium on the inside of the RF block?

Originally Posted by terminal fettler

Just ordered some of these bulbs to do a test. Also, from your pic of the ESB RF top that's partly hanging out, Rafalfett, it looks like there is a 1mm or so section of aluminium on the inside of the RF block?

That's great news!

I noticed too that there's something under the perspex block, and I assumed that its purpose is to let the perspex block to sit at a specific distance in the RF housing. Here is a drawing (a WiP of my new RF templates that will be awailable with my RWH v2 helmet templates) that shows with approximation these 'spacers':


The Rangefinder casing thickness is around 2mm and the spacers are 1mm for the ESB and 1.5mm for the ROTJ. The image is an interpretation of the movie era RF setup for both ESB and ROTJ.

Looks good there.

I just received a precision vice so have been able to accurately drill the three holes into the RF block. A nice slow speed and feed rate keeps the bit straight and doesn't melt the Perspex...

What a piece of beauty! Just need some light (I know they are on their way to you) and some experiment with them and we'll have some great rangefinders... I hope.

Keep up the great work!

RafalFett, you are brilliant and I can verify that you are indeed correct on both the wheat lamps and the 2 part Perspex. There are three wheat lamps in the perspex in addition to the two red LEDs that everyone already knows about.

Originally Posted by terminal fettler

it looks like there is a 1mm or so section of aluminium on the inside of the RF block?

This is correct. There is a paper thin sheet of polished metal glued to the top of the perspex block.

The metal is not a spacer, but serves to reflect the light of the wheat bulbs. Also, it covers the entire top of the perspex.

The perspex is simply pressure fit into the rangefinder (with doublesided tape holiding it in place). The reason you are seeing a difference between the RotJ and the ESB is most likely due to the perspex not having been cut exactly the same thickness from helmet to helmet.

Originally Posted by RafalFett

That's great news!

I noticed too that there's something under the perspex block, and I assumed that its purpose is to let the perspex block to sit at a specific distance in the RF housing. Here is a drawing (a WiP of my new RF templates that will be awailable with my RWH v2 helmet templates) that shows with approximation these 'spacers':


The Rangefinder casing thickness is around 2mm and the spacers are 1mm for the ESB and 1.5mm for the ROTJ. The image is an interpretation of the movie era RF setup for both ESB and ROTJ.

Originally Posted by Art Andrews

RafalFett, you are brilliant and I can verify that you are indeed correct on both the wheat lamps and the 2 part Perspex. There are three wheat lamps in the perspex in addition to the two red LEDs that everyone already knows about.

Thanks a lot Art!

Originally Posted by Art Andrews

The metal is not a spacer, but serves to reflect the light of the wheat bulbs. Also, it covers the entire top of the perspex.

That is a good explanation, but in the Pre-Pro #2 images there is definitely a square piece under the perspex block that doesn't cover the whole part:

Originally Posted by Art Andrews

The perspex is simply pressure fit into the rangefinder (with doublesided tape holiding it in place). The reason you are seeing a difference between the RotJ and the ESB is most likely due to the perspex not having been cut exactly the same thickness from helmet to helmet.

The thickness is the same and the best way to verify this is to check out the C-IV images for the ESB (the front corner of the perspex block is hanging out a bit) and the Heilman images for the ROTJ (the perspex block is also hanging out from the RF casing), the only major difference is the front cut angle (around 50 degree for ESB and 64 degree for the ROTJ), the lamp channel diameter and length (?) and the triangle is a bit bigger on the ROTJ (with 0.5mm), but again these are not set in stone and further research might change these values.

It looks like the PP2 might not have the metal section glued to the top of the block, so we are seeing the adhesive part through the Perspex.

Originally Posted by terminal fettler

It looks like the PP2 might not have the metal section glued to the top of the block, so we are seeing the adhesive part through the Perspex.

I understand! It's something like this:



The foil's thickness is around 0.33mm.

That's it. So on the PP2 the aluminium foil isn't there...
Because you have the wires running into the Perspex block powering the grain of wheat bulbs, when the adhesive strip fails, as seen on the ESB hero, the only thing preventing the block falling out are those wires. This is why the narrow end of the block has slipped out, revealing that aluminium backing sheet.

Added some of the images scattered through this thread to the first post, and some additional ones too.

This is much more accurate, although the metal is not foil. It is actually a surprisingly rigid little piece of metal.

Originally Posted by RafalFett

I understand! It's something like this:



The foil's thickness is around 0.33mm.

Originally Posted by terminal fettler

That's it. So on the PP2 the aluminium foil isn't there...

That would be my guess. The square you see in the top of the PP2, is very similar in shape and size to the doublesided tape.

Originally Posted by terminal fettler

Because you have the wires running into the Perspex block powering the grain of wheat bulbs, when the adhesive strip fails, as seen on the ESB hero, the only thing preventing the block falling out are those wires. This is why the narrow end of the block has slipped out, revealing that aluminium backing sheet.

No, the wires aren't what hold the perspex in. The perspex is primarily held in place via pressure from the sidewalls of the rangefinder top. The doublesided tape helps support it, but the pressure is the primary thing that hold it in place.

The grain of wheat bulbs are a good fit into the holes in the perspex, but aren't a tight fit. The wires are actually pretty strong and I suppose they could provide some support, but again, the true support is coming from the rangefinder body itself.

Originally Posted by RafalFett

The thickness is the same and the best way to verify this is to check out the C-IV images for the ESB (the front corner of the perspex block is hanging out a bit) and the Heilman images for the ROTJ (the perspex block is also hanging out from the RF casing), the only major difference is the front cut angle (around 50 degree for ESB and 64 degree for the ROTJ), the lamp channel diameter and length (?) and the triangle is a bit bigger on the ROTJ (with 0.5mm), but again these are not set in stone and further research might change these values.

I can't verify that the perspex are the same or different in thickness, but will say that they are clearly hand cut so there are differences.

Also, I think it is highly unlikely that the drill holes or drain of wheat bulbs would be different from helmet to helmet. There might be slight variances in the perxpex, but I would tend to believe those aspects are the same.

Originally Posted by Art Andrews

This is much more accurate, although the metal is not foil. It is actually a surprisingly rigid little piece of metal.

The aluminum foil was just a wild guess. So, a 0.5mm thick metal sheet is more accurate.

Originally Posted by Art Andrews

No, the wires aren't what hold the perspex in. The perspex is primarily held in place via pressure from the sidewalls of the rangefinder top. The doublesided tape helps support it, but the pressure is the primary thing that hold it in place.

The grain of wheat bulbs are a good fit into the holes in the perspex, but aren't a tight fit. The wires are actually pretty strong and I suppose they could provide some support, but again, the true support is coming from the rangefinder body itself.

I agree that the perspex block is (was) hold in place by the tight space with the RF casing, but also partially by the double sided adhesive tape and a bit from the GoW wires. But mainly the RF casing.

Originally Posted by Art Andrews

I can't verify that the perspex are the same or different in thickness, but will say that they are clearly hand cut so there are differences.

Also, I think it is highly unlikely that the drill holes or drain of wheat bulbs would be different from helmet to helmet. There might be slight variances in the perxpex, but I would tend to believe those aspects are the same.

I did some comparison images between the 6 rangefinders (the Sandy was the hardest in lack of reference images) and there are only 2 types of perspex body shapes used: the ESB style is (was) present on the Supertrooper/Pre-Pro #1 RF, while the ROTJ style is (was) present on the Pre-Pro #2, Pre-Pro #3 and Sandy helmets. It is possible that Brian Archer used a 12mm thick Perspex sheet (we can see a piece of Perspex in front of his table) and the only difference in style is the cut angle in the front and the triangle part cut at 45 degree but with slight differences (around 0.5mm or more). And I agree that is hard to say for sure the diameter of the GoW channels, but the ROTJ style looks a bit thinner than the ESB.

And I'm guessing the slightly angled in front side of the RF housing ( where as the back side of the housing is square to the top ) provides that grip from a bit of 'flex' in the housing material?

You may find the discrepancies in the three holes diameters may be caused by the drilling process. Too fast and not clearing out the Perspex swarf can result in a slightly larger bore...

Originally Posted by terminal fettler

And I'm guessing the slightly angled in front side of the RF housing ( where as the back side of the housing is square to the top ) provides that grip from a bit of 'flex' in the housing material?

It seems that the slight angle inward is also part of the 'grip'.

Originally Posted by terminal fettler

You may find the discrepancies in the three holes diameters may be caused by the drilling process. Too fast and not clearing out the Perspex swarf can result in a slightly larger bore...

You have to know better because you have worked with the actual material, so anything is possible. Whatever diameter you chose, I think is OK as long the GoW lamp fits that channel.

Originally Posted by terminal fettler

You may find the discrepancies in the three holes diameters may be caused by the drilling process. Too fast and not clearing out the Perspex swarf can result in a slightly larger bore...

Certainly there may be slight discrepancies (like the obvious discrepancies in the length of each hole), but I don't think there is enough of a difference to account for a different grain of wheat bulb being used.

Also, the grain of wheat bulbs are much longer than anything that has been posted so far. I did a quick google search and couldn't find any that directly matched the originals in overall shape.

This thread is a perfect example of what a forum should be; everyone working together to get the most accurate information. Art, thanks for starting this thing and allowing noobs like me to be a part of it.

Originally Posted by RafalFett

The aluminum foil was just a wild guess. So, a 0.5mm thick metal sheet is more accurate.

I would say 0.4mm...

Originally Posted by Art Andrews

Also, the grain of wheat bulbs are much longer than anything that has been posted so far. I did a quick google search and couldn't find any that directly matched the originals in overall shape.

I thought about longer lamps too (because of the ROTJ setup), but I couldn't find a GoW lamp with a length of 6mm or so and a 1-2mm diameter. If my ROTJ measurements are correct, than it has a GoW lamp with a 1-1.5mm diameter and the length is around 7-8mm, and this is a given lenght by the green wires inside the Perspex block channels.

Originally Posted by Art Andrews

I would say 0.4mm...

Then it is 0.4mm! Thanks for your support!

I would steer you in the direction of this shape.

Originally Posted by Art Andrews

I would steer you in the direction of this shape.

Now that is a great image! Thanks for posting! Will try to do more searching...

Using the image that Art posted as a guide (with some liberty, because I don't know that lamp's exact measurements) and also the image with the lit lamps inside the Perspex block (Slave I cockpit scene) I managed to get a fair value for the lamp's length, somewhere between 9-10mm:



But sadly I couldn't find something that is close to the one Art posted and in lack of the 'correct' GoW lamps we should stick to the available lamps on the net.

It is a little confusing based on the fact that the glass tube has a bit of a tail, but I would say 8mm X 2mm is pretty darn close. If you count the little tail piece of the glass you would be close to 9mm.

Originally Posted by Art Andrews

It is a little confusing based on the fact that the glass tube has a bit of a tail, but I would say 8mm X 2mm is pretty darn close. If you count the little tail piece of the glass you would be close to 9mm.

Yeah, I noticed the tail and my measurement included that part too. Thanks for clarifying the correct values!

Is Perspex different than plexi-glass?

different name for the same thing acrylic glass, plexi is a sheet of the same stuff used in the lense here. Its plastic.

Lights... Lights?

...Christmas lights!



This is a 4mm diameter and 10mm long light bulb used for Christmas light installation. The light bulb gets its power from a AC/DC adapter with adjustable values from 3V to 12V and the current value is set to 12V.



The RF casing is made from 2mm cardboard (an older work of mine) and the lamps are fitted with double sided adhesive tape (I know, I will need it at one point). The wires are temporarily attached between them in the following manner: the first wire of the first lamp is left open, then the other wire is twisted with the first wire of the second lamp (it doesn't matter which wire), then the second wire of the second lamp is twisted with the first wire of the third lamp and the other wire is left open to be later attached to the power source (in this case the AC/DC adapter).
The bulbs are powered with 12V and the intensity is not as good as the single bulb had but might work with a real Perspex block. I know these are wrong bulbs, but are a cheap variant and I wanted to see and post a first test of these lights.

Thoughts?

Came across some 2mm x 6.5mm dolls house lights, I think used for candles, not sure if they flicker or not though!

Originally Posted by terminal fettler

Came across some 2mm x 6.5mm dolls house lights, I think used for candles, not sure if they flicker or not though!

It is possible that these small lights to not work too well, and when I say small, I'm referring to the length not being long enough. I did a test 'Perspex block' by sandwiching 6 piece of transparent PVC sheets with a 1.5mm thickness, but not before I cut 3 stripes in 2 of the 6 sheets, so when I put all the sheets together, these cuts formed a channel for the Christmas lights (or GoW lights). I also found a 3mm diameter and 7mm long lamp on another Xmas light installation. And I forget to mention that you need to scratch off the paint on the lamp bulb with a cutter or hobby knife, so you will have your own transparent lamp.



The RF casing this time is my new version 'painted' with a black marker while the reflector material is a piece of baking aluminum foil.



I did some testing at 12V with the 'new' lights by first pushing the lights deep into the block and then I positioned the lights at the opening of the channels. The viewfinder is also a scratch build piece.





The result is not what I was expecting. But I said to myself that I need to try it with a lower voltage, so I did it with 3V then with 4.5V:





Kind of disappointing... We definitely need those longer lamps (2mm X 10mm) to replicate the long light seen inside the ESB Rangefinder in the Slave I cockpit scene. The hunt continues...

What about LED light pipes? I know it's not movie accurate, but they would disperse the light better, just a thought.

Maybe these could fit? Lionel Replacement Light Bulbs (4th item from the bottom), the "long clear" version. Says they are 1/8" in diameter and 12 volts.

Originally Posted by locitus

Maybe these could fit? Lionel Replacement Light Bulbs (4th item from the bottom), the "long clear" version. Says they are 1/8" in diameter and 12 volts.

That looks great but the diameter is 3mm and we need around 2mm for the ESB and around 1-1.5mm for the ROTJ. It might be a great replacement in lack of accurate lamps. Thanks for posting!

Dang, I should have bothered with the unit conversion!

While not as tall as the others, these are 2 mm and 12 v
Amazon.com: Dollhouse Miniature Four Bi-Pin Micro Grain of Rice Bulbs: Toys & Games

Originally Posted by locitus

While not as tall as the others, these are 2 mm and 12 v
Amazon.com: Dollhouse Miniature Four Bi-Pin Micro Grain of Rice Bulbs: Toys & Games

It is pretty close with its 7mm length...

Hm, I must have missed that spec. But yeah, 7 mm is pretty good.

Originally Posted by locitus

Hm, I must have missed that spec. But yeah, 7 mm is pretty good.

It don't say the length, I get the 7mm by reducing the image to a 2mm diameter bulb.

Ah. Clever!

I think if laser pointers were around during ESB, Lucas would have thrown one in that view finder. how cool would that be?

This post is not exactly an update, but more like a show off of a beautiful piece I received today from Garrett (terminal fettler - thanks again!), more exactly an exact replica of the ESB Hero Perspex lens block and Polaroid Viewfinder (the RF casing is my cardboard replica):



I have no words to praise the craftsmanship involved in these pieces, especially that these are so tiny and I highly recommend them for anyone who strive for accuracy (the images don't do justice for them). It has the correct inner channels, the metal foil (or sheet) glued to the bottom of the block, which is made with 2 separate pieces glued together. We just need to find the correct GoW lamps and made them light up!

And for fun I did the ROTJ Perspex block 'replica' by inserting 3 piece of green elastic (didn't find wires with green isolation):



I'm so happy (and fortunate) to own these perfect replicas!

Wow! Very nice! I was wondering how this was coming along. Once everything gets sorted out, I hope these become available for purchase.

I think that these will be available very soon, but better PM terminal fettler (Garrett) for more info.

Raf, how does the TF rf compare size wise with the Asok rf? Right now I'm designing a self contained led board for the Asok rf and would like to know if it would fit in a TF one.

I don't know the Asok RF measurements but from what info I got from TF, his setup has the correct values. But it also depends on the thickness of the materials too. Here are my measurements of the rangefinder casing and perspex block:



Note that the RF casing should have a 2mm thickness.

Thanks Raf, just another example of "you da man".

thank you for sharing this Rafal

Originally Posted by RafalFett

I don't know the Asok RF measurements but from what info I got from TF, his setup has the correct values. But it also depends on the thickness of the materials too. Here are my measurements of the rangefinder casing and perspex block:



Note that the RF casing should have a 2mm thickness.

Originally Posted by Terrible Rid

thank you for sharing this Rafal

You're welcome!

i know they used lots of fiber optics to put light where they wanted from one source to more areas..maybe they used fiber optic threads?

Originally Posted by Megatron

i know they used lots of fiber optics to put light where they wanted from one source to more areas..maybe they used fiber optic threads?

While this is a good choice, according to the Supertrooper parts sheet, they used lamps (or bulbs) in the rangefinder. Here is the closest thing posted by Art:

Originally Posted by Art Andrews

I would steer you in the direction of this shape.