Sunday, February 27, 2011

How I Made My Darth Vader Chest Armor



The purpose of this tutorial is to explain how I made my Darth Vader chest and shoulder armor.  Several people have asked how I accomplished this and why I chose to attempt it.  If you want a Vader Costume, you’ve got to get some armor.  I was nervous sending hundreds of dollars away for mail order armor that I couldn’t evaluate in person.  And I wanted a challenge.  When I finished, I wanted to be able to say, “I made it”.  I’m not sure If would recommend this or do it again though.  It’s still not as “mint” as I would like it.  I’m hoping to refinish sometime in the future.  But for now, it is acceptable for the 501st.  There were times in the process when I had doubts that I would ever finish.  It took 4 months of nights and weekends, not counting the computer modeling time.  But I’m pretty proud of the finished product.

This is NOT the only way to make armor but it was the most economical, straight forward way to get a high quality product that fit me.  You may not follow my steps exactly but hopefully, you will learn something of value from the time you spend reading this. When I started this project, I knew a little about designing shapes and structures.  But I learned a lot of practical things that may help someone else.  I also need to preface that I had the advantage of owning a garage full of power tools.  But everything I did with power tools could be done with hand tools; it’ll just take a lot longer.

I did a 3-D computer model to simulate my armor before I started to build it.  This process had worked well for me when I did shin armor.  The first thing I needed was to determine the size and shape of the armor.  I wanted armor that fit me, not David Prowse.  So I needed to get some idea of what my shape was.  I set up my camera on a tripod and took a front and a side picture of myself, making sure to stand the same distance from the camera.  This is important so the side and the front picture are the same scale when used for the next step.  I loaded both pictures into PowerPoint and made some basic curves to outline my shape.  Notice that the pictures are to scale with one another.  This is important as you will see later. 




Now that I had the basic shape curves I had to figure out how big they are in real life.  I stood in a doorway with one arm up against the door jam.  Then my son measured the distance from my other arm to the other side of the doorway.  I subtracted this number from the total width of the door.  The difference was my width.  Once I had determined the width the other dimensions shown below were determined using relational geometry.  Relational geometry says if you know the true length of something in a picture, you can determine the true lengths of other things by measuring their length in the photo and using ratios.  Here’s an easy example:  You have a photo of a man and woman standing side by side.  You know the man is 72 inches (6 ft) tall and he measures 4 inches tall in the photo.  You want to know how tall the woman is.  She measures 3.5 inches tall in the photo.  You set it up like this:

72 / 4 = H / 3.5; Where H is the height of the woman.

Multiply both sides of the equation by 3.5to get H by itself

3.5 X ( 72 / 4) = (H / 3.5) X 3.5

3.5 X 72 / 4 = H

63 = H

So the woman in the photo is 63 inches tall (5 ft 3 inches).

Using the same type of calculations I determined a few more distances of myself.




Now that I had my size and shape it was time to make a master surface.

I loaded my curves into a Computer Aided Design (CAD) program and created a 3-D surface that ran approximately through the curves.  The master surface needed to be smooth and flowing.  This was the base upon which all the features will be built.




Then I overlaid a screen grab to figure where the raised features needed to go.  Vader’s chest armor has four “levels” and a divot:  The base level (gunmetal grey) goes from left shoulder to right shoulder and chest to back. The second level contains one strip that goes over each shoulder and the wider center section (black). The third level is the narrower center section (gunmetal grey). And the forth level is the narrow center strip in the middle of the chest.  The divot is a sloping area within the second level that tapers down to the base level.  Without having an actual piece of armor to measure I had to make an educated guess that each level was 1/8 or .125 inch thick.  This was also a choice of convenience since this matches three layers of fiberglass and one layer of foam as you’ll see later.



Notice that I only worried about the left side.  The software I used “mirrored” one side to create the other side.

When I was done my 3-D model looked like this.



This model is a hybrid of the armor worn in the original trilogy and ROTS.  The armor worn in ANH, ESB, and ROTJ had no back immediately behind the neck.  I didn’t like this for two reasons.  First, since all the weight was in the front, the armor would be unbalanced and tend to slip forward.  Second, with the gap behind the neck, the cape wouldn’t hang level across the shoulders.  The armor from ROTS went all around the back but it doesn’t have the raised pattern on the shoulders and it has a second over-the-shoulder strip at the edge of the chest, adjacent to the shoulders.  I chose to make ESB armor to match what I had for a helmet, but I liked the all around configuration for better balance.  One disadvantage of this is that the neck opening just barely accommodates my big head.

Now, how did the 3-D computer model become reality?  I needed to make a LAYUP TOOL on which to do fiber glassing.  I went back to the base surface and made a section cut from front to back, right at the center.  Then I made side to side section cuts every ¾ inch, starting in the center at the highest point of my surface and working forward and aft.  I put a point where the edge of a feature crossed the section cuts.  My cuts and points looked like this.


Since the surface and features should be symmetric from left to right only half of the front and half of the back is needed.  This is similar to how a boat builder builds the hull of a boat.  The boat plans will show the front of the boat on one side of center and the back of the boat on the other.  In the engineering profession we refer to these section cut curves as LOFT LINES.



If you would like a copy of the above at full scale I have it available in pdf format.  Email me and I’ll email it to you.  You will need to adjust the scale to fit yourself.

I printed out the loft lines full scale.  I had three copies printed at Kinko’s. I cut out a template for the largest side to side section cut curve and for the center front to back section cut curve.



I pasted these onto a board of wood.  I used the cheapest pine I could find.  Medium Density Fiber (MDF) board or ¾ inch plywood may work as well but I haven’t tried it.  I had to join two boards, edge to edge with wood biscuits, to have enough material width.  I used Elmer’s spray adhesive to glue the templates onto the wood.  Spray lightly because you want to be able to remove the templates from the wood later.  Also, too much adhesive will make your paper swell and wrinkle.  Lesson Learned: 3M 777 spray glue is not water based so it won’t wrinkle paper templates.

I cut out the side to side shape with my band saw.  Next I cut out the center front to back section cut curve.  The center front to back curve needs to have a ¾ gap at the location where the side to side curve will cross the front to back curve.

I glued and screwed the front piece to the front of the side to side piece.  I used a set of steel corner angles from the hardware store.  Then I glued the back piece to the back of the side to side piece.  Looking down on this contraption you’ll see a cross.



Then I needed to build out the front of my layup tool.  I pasted another copy of my forward loft lines onto a board.  I stacked this board on top of another board so that I would get two identical pieces from cutting.  I cut out a shape that followed the second largest loft line and the 5th largest loft line.  It also needed to have a 3/8 inch section taken out at the top to make room for the front piece.

My piece looked like this.



I put a little “Tick Mark” cut in the outer edge of this piece wherever a feature edge crossed the loft line.  This would help me later lay out the features on the layup tool.

I glued these two pieces onto the side to side shape.


I repeated this process.  The next pieces followed the 3rd and 6th loft curves.  I alternated pieces like this for two reasons.  It used less wood and loft line prints.  This way every third curve can be cut from the same piece of wood.  And the tool would be much lighter.  It was a little tricky gluing it this way and it took a little longer to assemble.






After the front was done, I flipped the tool over and built out the back.  When I was done, my layup tool looked like this.



The next thing to do was sand down the “Saw Tooth”.  I used a heavy duty right angle grinder with a 7 inch abrasive wheel on it.  This was sort of like three dimensional connect the dots.  Working on the front side of the tool, the aft edge of each piece was one of my loft lines.  I sanded down the saw tooth shaped steps of each piece until I got close to the aft edge.  When I got close, I filled any gaps, knots and tick marks with wood putty.  After the putty dried I sanded it flush.  The wood putty has just enough difference in color from the surrounding pine that I could clearly see my tick marks.



After it was sanded nice and smooth I covered it with a thick coat of fiber glass resin.  I used Bondo brand fiberglass resin that I purchased at Wal-Mart.  It can also be found at hardware and auto parts stores.  Follow the safety and mixing directions.  Wear safety glasses.  It took about two cups to cover your layup tool.

This is a good place to talk some more about resin.  Bondo Fiberglass Resin comes in a metal container with a little, plastic, tube of catalyst under a plastic cap.  According to the directions, you are supposed to mix 12 drops of catalyst to each ounce of resin.  The catalyst starts an exothermic reaction in the resin that makes it cure.  As it cures it transitions from a liquid with the viscosity similar to syrup to a solid.  Exothermic means it heats up.  This is why I bring this up.  Get too much catalyst in your mix and your resin can get hot enough to burn you.  So avoid getting it on your skin.  If you get some curing resin on your skin, you can wipe it off with rag dampened with acetone.

Also, don’t mix large amounts of resin all at once.  Larger amounts give off more heat, faster.  And it may end up curing before you have it all applied.

The other thing to consider is how hot is the area in which you are working and the temperature of your resin.  At 70 degrees F. 12 drops per ounce will give you about 12 minutes of working life.  If it’s 90 degrees F. with 12 drops, you may have about 9 minutes.  So you can reduce the number of drops of catalyst to increase your working life.  If it’s 40 degrees though, 12 drops of catalyst will give you 15 minutes or longer of working life, but it won’t fully cure for hours.  You can speed this up by heating the partially cured part with a heat gun.  You don’t want to burn it so keep the gun moving.  Don’t let it dwell at any one spot for too long.  Don’t vary the amount of catalyst more than 25%.  As I’ve said, too much catalyst can cause the resin to be dangerously hot while not enough and your part may never fully cure.

Also, resin stinks like concentrated model airplane glue.  Work in a well ventilated area and wear a breath mask. 

Back to the tool.  After the resin cured, I sanded out any runs.  I was careful I didn’t sand all the way back down to the base wood because I’m using the resin as a sealer.  After sanding my layup tool looked like this.


These pictures show the outlines of the armor drawn on top of the tool with pencil.  This was done by connecting the tick marks with smooth curves.

Now I was ready to lay up a test part. Before I went any further I wanted to make sure the armor would fit when I was done.  The neat thing about cured fiberglass resin is that it doesn’t bond to new resin.  It will stick, but there’s no chemical cross linking between the cured resin and the new resin.  To minimize the sticking I applied several coats of carnuba wax to the layup tool.  Wax with silicone in it will cause the new resin to pool. I left the last coat un-buffed.  The dry, “frosty” wax has just enough tooth that the resin will cling to the surface when wet but won’t stick after it’s cured. 

I made my test part by laying up two plies of Bondo brand fiberglass, starting at the center front, going over the right shoulder to the center back.  I found that a silicon, basting brush from the kitchen gadget aisle worked well for spreading resin. When the resin cures it peels off the silicon bristles in one piece.  I had to make some cuts in the fiber glass over the rounded part of the shoulder to get it to conform without wrinkles.  Before that was fully cured, I laid up two pieces on the left side, making sure to overlap the pieces on the right side.  The overlaps allow the strong fiberglass to carry loads from the one piece to the next.  Without the overlaps the resin, all by itself, tends to crack.  I left that cure for a few hours.

I worked a thin, steel ruler under the edges until the piece popped off the tool.  A neat thing happened.  Because I had drawn my feature lines on the tool in pencil, the resin had lifted some of the pencil graphite up on my test part; Like Silly Putty lifts up a newspaper comic.  I trimmed my test part with aviation snips and a Dremel and it looked like this.



I was really pleased with the fit.

So now it was time to start on the real part.  I was comfortable with my layup tool, the drapability of the fiber glass fabric, and mixing and applying the resin. So I laid up one ply, center front to center back, over the right shoulder, just like the test part except I stopped just past the top of the shoulder since the shoulder bells would be made later.  I repeated for the left side.

While that was curing I went back to my test part.  I trimmed off the shoulder bells and cut it up the back centerline.  With the back split I was able to open and flatten the part.  It was too stiff to flatten completely but it was close enough to use as a pattern to cut my foam.

Fiber glass has a very high tensile strength, but it needs to be stacked several layers thick to have any bending stiffness.  This can make it heavy.  Another way to increase the stiffness is to separate the layers of glass with another, lighter material.  I used craft foam.  It’s about .090 inch thick.  You can find it at just about any craft store sold in sheets but my local Michael’s craft store sells it in rolls.

I rolled out my foam, put my test part on top, traced it from the front centerline to the back centerline and cut it out.  I left excess because it was important to cover all the area in one shot.  The excess would be trimmed later with the excess fiber glass.

I went back to my cured layer of fiberglass resting on the layup tool.  I scuffed sanded the surface with some 60 grit sandpaper.  Scuff sanding takes the shine off the resin and gives the epoxy in the next step a rough surface on which to bite.  I wiped off the dust from sanding with a rag dampened with rubbing alcohol.  I mixed up some 5 minute epoxy and spread it on my foam.  Working quickly I draped the right hand piece of the foam over the one layer of fiberglass.  I applied continuous pressure by rubbing the foam from the shoulder down until the epoxy had cured.  Then I repeated the process on the left side.

Then I got some more fiberglass fabric ready for what would be the single, largest step in my armor fabrication.  I wanted two layers of fiberglass as my outer surface for extra strength.  I brushed some resin onto the foam and one right side ply, one left side ply overlapping in the center, then another right and left again overlapping but this time I staggered it so the second overlap splice was not on top of the first overlap splice.  Then I brushed on additional resin until all the glass was saturated.  You can tell when the fiber glass is saturated when it changes from white to semi transparent.  The resin has plenty of strength to bond the fiber glass to the foam.  This completed the base level of my armor.

Next I started building the features.  I returned again to my test part.  This time I trimmed out the second layer, center section.  Again, I used this piece as a pattern to cut my craft foam.  I cut the craft foam such that the fiber glass would over hang by 1/8 inch. You’ll see why later.  The second layer, center section is complicated by the two divots.  These need to be cut out of the foam.  When the foam was ready I bonded it to the base level with 5 minute epoxy.



At this point I could have laid up fresh pieces of fiber glass.  But instead I decided to use the center section from the test part.  First I cut out the divots as neat and symmetric as I could.  Then I applied some 5 minute epoxy to the center section and bonded the fiber glass to the foam.  At this point I noticed a small flaw in my plan.  The test piece was made right on top of the layup tool.  Now the tool had a layer of fiberglass, a layer of foam, and two more layers of fiberglass on it.  This caused the fiberglass center section from the test part to be a little short.  I decided to line up the front and let the back be short.  I could fix it up later.  Besides, the back is always under the cape so no one ever sees it.  Lesson learned:  If I were to do this again, I’d keep a lot more excess trim on the test part.   

Next I tackled the over-the–shoulder ridges in similar fashion.  I trimmed my test part down to the ridges and used them as a pattern to cut the foam.  Having learned my lesson on the center section, I cut the foam with a lot of excess.  I took my foam pieces and taped them on top of the base level.  Then I positioned the ridges from the test part on top of the foam.  When I was happy with the location I bonded the test part ridges to the foam with 5 minute epoxy.  When the epoxy was cured, I untaped my ridges, and trimmed off the excess foam.  I undercut the foam about a 1/8 all around so the fiber glass overhung the foam; You’ll see later.  Finally I bonded the ridges to the base level with 5 minute epoxy.

This may seem a backwards way of doing it but there is a method to my madness.  If I cut the foam to match the test part ridges with no excess, as I wrapped the foam over the shoulder, the ridge would no longer line up.  If the ridges were straight, this would not be an issue.  But because they have curves, the curves will mismatch as they start going over the shoulder.  If I bonded the test part ridge and foam together on a flat table and then tried to force it over the shoulder, the foam would resist compressing and the fiberglass would resist stretching.  This may have worked, but it may have also buckled the foam.  If I bonded a wide piece of foam to the base level, then bonded the test part ridge to the foam, and finally trimmed the foam, I would have had a bunch of cured epoxy to sand off the base level. 

I wish I had some more pictures of these intermediate steps.  But at the time I was more concerned with getting done than documenting for posterity.

Next task was to fill out the divots.  Oh those damn divots.  How I cursed the designed of these divots.  The divots transition from the second level at the top, to the base level at the bottom.  I got the divot areas I had cut out of the test piece.  I bonded a 1/8 inch wide strip of foam to the base level, at the top edge of the divot.  This would keep the top of the test piece divot at the same height at the center section.

Then I mixed up some resin and micro balloon.  Microbalance, also known as glass bubbles, is a 3M product.  They are microscopic, hollow, spheres of glass.  They look like flour. But when you mix them with resin or epoxy, they make a lightweight paste that is strong, durable, and sandable when the resin/ epoxy cures.  I purchase micro balloons from http://www.aircraftspruce.com/.  Two parts by volume of micro balloon mixed with one part resin or epoxy has the consistency of spackle.  It can be spread with a putty knife.  I use a silicon, kitchen spatula for large areas and artist spatulas for small areas.  An interesting aside:  I listened to the Empire Strikes Back Special Effects panel at STAR WARS Celebration V.  One of the speakers mentioned that they used micro balloons to simulate snow around the model AT-ATs.

Back to the divots.  I smeared in a bunch of resin/micro balloon into the divot.  Then I took the divot area from the test piece and placed it in the divot.  Then I used the straight edge of a Popsicle stick to push the test piece divot down into the resin/micro balloon such that the top rested on the foam strip, the bottom rested on the base level, and the rest of the test piece divot was straight.  Some of the resin/mico balloon oozed out around the edges but that was expected.  It was more important that the test piece divot was near fully supported by the resin/micro balloon.  The excess could be sanded down after it cured.

After the excess resin/micro balloon had been sanded, I mixed up some more, and tried to get a nice round fillet around the inside edge of the divot.  This took a couple attempts to get to where I was satisfied.  I finally decided to put in extra resin/micro balloon, let it cure, then sand it with a sanding stick I made by gluing sandpaper wrapped around a ¼ dia wood dowel.

Next I had to build the third level.  I sketched out the edges of this area on top of the second layer.  I cut a piece of foam to match.  I placed a piece of wax paper over the area and secured it with masking tape.  Then I positioned the foam on top of the wax paper, lining up the edges with the sketch, and taking the foam in place with a few small dots of hot glue.  Then I covered the foam with two layers of fiberglass and resin.  After it cured, I lifted the foam/fiber glass off the wax paper.  I had to transfer the sketch to the foam with some tracing paper.  Then I trimmed the foam/fiber glass net and then undercut the foam such that the fiberglass overhung the foam by 1/8 inch.

Now I had come to the fourth level.  The fourth level is a narrow strip, about a 1/4 inch wide, front and center.  I cut a piece of foam 1/8 wide and bonded it with 5 minute epoxy on the third level in the center.  Finally I needed a flat piece of fiberglass, 1/4 wide.  Here’s another neat thing about Bondo Fiberglass resin.  It won’t attack certain plastics, including cellophane.  So I took a piece of cellophane packing tape, about two inches wide by ten inches long and applied it to the flat surface of my workbench.  On top of the cellophane I laid up two plies of fiber glass/resin.  When it cured I trimmed it to ¼ inch wide and bonded it on top of the 1/8 wide foam.

At this point, I trimmed the edges and neck hole.  It took a couple of tries to get the neck hole large enough.  With the edges trimmed I had to address all the exposed foam and those undercuts.  Where the foam was all the way to the edge, even with the fiber glass, I used a wire brush attachment on my Dremel to “brush” the foam out from between the plies of fiberglass.  It worked remarkable well.  The foam doesn’t stand up to the fast rotating wire bristles but the fiber glass is unharmed as long as you don’t linger in one spot.  I was left with the foam cut back about a 1/8 inch.  To make a solid edge, I filled this gap with resin/micro balloon.  I mixed up my paste and put it into a paper cup; The kind that are cone shaped.  I cut off the tip of the cone, and rolled the lip of the cup over on itself to seal the top.  Then I injected the resin/micro balloon into the gap the same way a cake decorator squirts frosting.  After the resin cured, I sanded the edges until they were nice and square.

In similar fashion I used resin/micro balloon to seal the edges of the raised levels.  I left excess, then after curing, sanded it down with a piece of sandpaper wrapped around a ¼ dia dowel.  This left a nice fillet radius transition around the base of each level.  Between the third and fourth level, I used sandpaper wrapped around a paper towel roll to get a larger radius.

In the following pictures, the white areas are the sanded resin/micro balloon.  Notice that I used it to fill some low spots as well.  Sometimes, when I was in a hurry, I’d use 5 minute epoxy in place of the resin.  It was a little harder to sand but it cures faster and sticks to flat areas better.






If you’ve survived this long I won’t bore you with all the details of building the shoulder bells.  The technique is the same: Layer of glass, layer of foam, two layers of glass, with another layer of foam and two layers of glass to create the raised features.  The shoulders are where the compound curvature is most severe prohibiting the fiberglass sheet from laying wrinkle free.  Did you ever try to gift wrap a basket ball?  I had to make a few cuts in each piece of fiber glass to allow it to conform and overlap.  I will also share that I returned to the test piece one last time and, at the advice of my seamstress wife, used the shoulders to make a pattern for my foam.  I made vertical cuts in the test piece shoulder bell to allow it to flatten.  Then I used the flattened piece as a template for the foam.  The following photo shows the foam bonded to the first layer of fiber glass.  Notice the vertical cuts in the foam which allow it to conform.



When the three pieces were ready, I filled all the pinholes with spot putty; The pink stuff from the automotive store.  Then I painted with a couple coats of sandable primer.  Then I painted the gunmetal grey and finally masked off the grey and painted the black.  I used Duplicolor enamel from the auto parts store.  I won’t go into detail with painting because frankly, it didn’t turn out as well as I would have liked.  It may have been too hot and/or humid.












When my armor was all done I covered the inside with dark felt using hot glue and attached the shoulder bells with black elastic and Velcro.  The felt keeps the hard fiberglass from scratching my leather body suit.  The elastic allows the shoulder bells to move and the Velcro allows the bells to be removed for storage and transportation.

This brings my long winded tutorial to an end.  I hope you found it helpful.  I have to say that I would never have attempted such an endeavor if it weren’t for one of my co-workers who was building an ultra-light in his garage.  My tool making technique is a cheaper variation of a technique he used to make his wing tips.  As it turns out, building an ultra-light is not rocket science, and neither is making Darth Vader chest armor.

15 comments:

  1. Hi Amazing job - I would love to get a PDF plan for your layup tool- my email address is david.goff3@ntlworld.com

    one other thing is your suit actually leather or "simulated" leather
    Thank you for uch an informative post - you have saved a lot of people a lot of time :)

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  2. Olá estou procurando fazer essa peça do darth, mas não achei nada. Você poderia me enviar por gentileza o pdf?

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  3. Awsome!!! Can you send me the PDF plan as well to matiasmandagaran@gmail.com ?

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  4. Sensacional, ótimo trabalho! poderia me enviar o PDF? felipy268@gmail.com

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  5. Perfeito!! Também preciso da moldura da armadura do peito, por favor
    msciencio9@outlook.com

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  6. That is amazing! I'd also love to get pdf plan or cad model safetyboat1@gmail.com

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  7. Looks amazing. Could you send the pdf or the cad file to Mark.coleman2821@gmail.com

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  8. awesome ! Could you send the pdf or the cad file to ngoancuong83@gmail.com

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  9. Can you send me the PDF plan as well to robinschultz@live.dk ?

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  10. This is exactly the tutorial I was looking for. Well done. Do you still have the PDF or cad file available. If so, could I get a copy? jaxfiancee@gmail.com Thanks

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  11. This is exactly the tutorial I was looking for. Do you still have the PDF or whatever kin of file available. If so, could I get a copy? paolopaolo.dt@gmail.com Thanks

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  12. Could i get a copy of the pdf at gasanchez4@gmail.com, thanks!

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  13. Thank you for this tutorial. I will refer to it often during my project. Amazing job!

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  14. Por favor podría enviarme el pdf. Muchas gracias vcmanuel13@gmail.com

    ReplyDelete