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T.J.L.

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Everything posted by T.J.L.

  1. This answer likely comes too late but maybe it will be of use for someone else. I used a sealant which is meant for attaching car windscreens. It seals very well and also makes a strong bond. The bond doesn't even have to be that good since the pressure anyway pushes the dome against the seal.
  2. Now that it was time for my annual visit to this thread, I can finally share also the pics of the dive light holder for the last trip to Central America. It was not actually a huge success (the holder, not the trip). I used a leg from a gorillapod and 3D printed the mounting parts. First of all, the leg was too bendy so the dive light did not stay in position. It was ok initially but got worse as the trip went on. Secondly, I printed the parts of PLA which seemed to stretch slowly when kept in tension for weeks. Initially, for example the mounting of the dive light to the leg was very solid but at the end of the trip I had to but some rubber between the parts and the light in order to keep it fixed. I guess an easy fix for this would have been to always disassemble the holder so it parts would have been in tension only when diving. I hope the links work. https://1drv.ms/u/s!AgRk430IqP82go022w-vmxZCmN2PIA https://1drv.ms/u/s!AgRk430IqP82go00dR0kMfTiEe7CTw The diving in Honduras (Cayos Cochinos and Utila) was nice but kind of left me missing diving in the Philippines and Indonesia. The following was a pretty awesome encounter though. Too bad the dive light is dangling in the view and I was watching the ray from the side of the camera so the aim is not perfect all the time. https://1drv.ms/v/s!AgRk430IqP82hK93NyIcCCQ7WZeTpw BTW. Can anyone compare diving in the southern coat of Sri Lanka to diving in Honduras or SE Asia?
  3. With the new thicker back cover getting a good seal was not an issue anymore. There was not really space to add more latches. The biggest problem with the latches was that their tightness was not adjustable so I basically had to shape the parts attached to the back cover so that I get approximately proper tension. I think the stress cracks were caused by me using (way) too high a moment for the screws attaching the latch parts to the back cover. The cracks started from the screw threads and never really seemed to compromise the integrity of the whole back cover. Oh and the back cover is polycarbonate, not acrylic. I would be too paranoid of cracking with an acrylic back cover. I did consider using a two-part back cover but that would prevent me from seeing leakage at the edges of the cover. I never considered using vacuum but I did consider some kind of a leak detector. On the other hand now that the back cover is completely clear, any leaks are easy to spot visually.
  4. You can search for "eriks oring calculator" for o-ring dimensioning. I guess in theory any cross section o-ring would work but with about 1.5-2.5 mm cross section, 0.2 mm of compression is enough for a good seal. That kind of a compression should be easy to maintain reliably even with loose manufacturing tolerances.Of course if you use a smaller cross section, the O-ring groove will use less space in your design. Since for example the O-ring between the port and the body is static, I am using a quite large compression. With the button O-rings you have to remember that a larger compression leads to more friction. For the button return springs forces, I mainly calculated the pressure force acting on the button shaft cross section area at some depth and then added some safety margin to account for the friction of the O-ring. The first springs I bought were a bit too weak to work reliably when going deeper so I had to change them. I would advise buying too rather too strong than too weak springs. It is not nice to have the shutter button jammed down in the middle of the dive. The aluminum I bought from Protoshop in Espoo but unfortunately it does not exist anymore. I do not know where in Helsinki area one can buy metals easily in small quantities anymore. It is a bit of a problem for me as well... For anodizing, I used Alumiinikilpi in Helsinki. The guys are grumpy old farts who do not really care about customer service, especially when calling them. But when I went there and they saw that I had really put some effort in this project, I got really good service with a good price.
  5. Nice! Very professional looking. Is that completely self designed and built? Is the body made of aluminum? Is the port on the left hand side some kind on a sync port? Is the tightness of the latches adjustable or how did you ensure correct latch tightness? Sorry for not answering sooner, I guess its no more a current issue but maybe this will help someone else. Even though epoxy seems to be the best all around glue, I did not use it for the dome. I used windshield adhesive since it provides a strong adhesion but also stays relatively elastic. Therefore, it will not get any cracks and the water pressure will always seal the dome against the soft adhesive layer even though there would be some imperfection in the contact. Downside was that windshield adhesive was difficult to apply cleanly and very difficult to clean from the internal gap between the dome and the port body.
  6. Greetings from Honduras! I'll be happy to answer any questions. I've had the housing with me now on about ten dives on this trip and it has worked decently. I've had a couple of drops of leakage, probably because I never got to improving the partly DIY latches. They could compress the back cover oring a bit more on the surface. Water pressure takes care of compressing the oring properly when going deeper. Another problem is the shutter button. For some reason it sticks if its oring is not cleaned and greased often. This probably has something to do with the fact that this button has that horizontal 3D printed extension which causes some torque on the button but I am not sure what the problem is exactly. I did buy a dive light and mounted it to the camera housing. I'll add some pics from the dives and of the dive light arm a bit later.
  7. Long time no see. I wondered back here to look for ideas on how to make a cheap blue dive light for fluorescence diving and noticed this old thread. A small update on the camera housing. After the Philippines trip I had the camera with me on another 6-week trip to Indonesia in 2015. The housing worked excellent. If I remember correctly I machined a new even thicker polycarbonate back cover to replace the slightly cracked old one. Next month we are leaving to Mexico and Central America for three months and I am not yet sure if I'll take the housing with me. We may not be diving as much as before and the housing is kinda bulky to carry in my 45 liter backpack. Fortunately I am still using the E-M5 so no need to update the housing due to a new camera. I did plan to make an optically synced strobe for the housing but never got to it and definitely do not have the time before the next trip. I might buy a decent dive light and fix up an arm to attach it to the camera. That might already improve the photographs a little.
  8. Now it's finally time some concluding thoughts about this project. First the expenses. Building a proper housing is not a cheap hobby. I documented most of the expenses and the total cost for the housing was about 350 euros. Most of this is just materials since I get to use the milling machines etc. for free. The materials are expensive at least here in Finland especially when you buy just a small piece at at time. The most expensive part of the housing was the Ikelite 5503.15 dome which I bought second hand for 100 euros. Material Pcs Price per piece eur Total 14 mm bull end mill 1 37,65 37,65 Aluminum for the body 1 37,94 37,94 Latches 3 7,9 23,7 Aluminum for the port 1 17,55 17,55 Dome 1 100 100 Springs for the buttons 10 3 30 Stainless bolts etc. 30 0,6 18 O-rings for the buttons 10 1 10 O-rings for the port and back cover 1 10 10 Polycarbonate for the back cover 1 24,6 24,6 Piece of PC and stainless steel 1 4,4 4,4 Anodization 1 30 30 Bike spokes 2 0 0 3D printing Aluminum for buttons Misc screws Epoxy glue Misc cutting tools Piece of stainless sheet 343,84 Second, the time used. I did not really keep track of the hours, but I can try to estimate. Creating the CAD model took probably over a hundred hours even though the housing was very similar to the previous one I made. I started really building the housing just a couple of weeks before the trip but after that I spent most of my time doing it. Therefore, the building part was probably also around a hundred hours, including making the toolpaths for the CNC machines. So all in all maybe 200 hours. And the lessons learned. 1. Start early if you have a deadline. Really early. Building anything takes longer that you think. 2. If you want to get things ready, try to use off the shelf parts. For example, I partly remade the back cover latches and they turned out to be on of the weakest spots of the housing. On the other hand I could not find exactly the kind of latches I wanted so my options were limited. 3. Design properly and well. CAD modelling is essential. I had not completely assembled the housing a single time when we left for our trip. Even so, almost everything worked as planned because all the parts were fitted together in the CAD model. The FEM simulations also eased my mind regarding the rigidity of the housing. It also took me just a half an hour to make them. I don't know if there are any free FEM packages available for stress simulations but if you have access for a FEM program, a simulation is very easy to make when you have the CAD model. 4. The 3D printed prototype was great in testing the ergonomics. 5. Polycarbonate seems to develop cracks in time if it is under constant stress. Even though my polycarbonate parts were never in contact with any solvents, I still got cracks in some threads of the back cover. I think the screws should just not be tightened so much. 6. Design the o-ring grooves properly. Remember that the o-ring adds friction to the buttons and the friction is larger the more o-ring is compressed. Think also beforehand how you are going to install the o-rings. They can be a pain in the ass to squeeze into a tight groove on the bottom of a bore. 7. Make everything from plastic or stainless steel, also the springs, bolts, etc. Also most aluminum alloys will oxidize in salt water if they are not anodized. Anodization can be done at home and it is not too difficult, just requires some experimentation with the dyes. On the other hand I paid 30 euros for anodizing the main parts by a professional so a DIY setup may not even be the cheapest option. I guess that's all that comes to my mind now. DIYing is a great hobby but if you just want an underwater housing, it's easier to work some extra hours and save money for an off the shelf housing .
  9. I am planning to. That's why I have the optical sync port in the housing. Also the back cover and all the buttons will have to be remade again but I hope that will take just a couple of days. Next time I am definitely not going to built a totally new housing...
  10. I still have not sorted or adjusted the pics properly but since some of you are eager to see some results, here are a few totally unprocessed pics. Most of these are taken with the Samyang fisheye prefocused somewhere so the subject might or might not be in focus. Also the fishey of course has distortion. I thought I could live with manual focus but now I hope I would have bought an auto focus lens. The Panasonic 20 mm was nice though. I'll maybe add some more pics after a conference trip. Small wreck at Apo reef. Samyang, CA visible on top. Samyang, the brand nicely visible in reflection. I'd suggest covering any white text on the lens . Panasonic 20mm. Corners are quite soft. Panasonic 20 mm. Some macro with Samyang.
  11. I hope the housing will be strong enough to take the pressure. Will you use vacuum to remove all the bubbles from the resin? In my housing the o-ring stays nicely in the groove even with the rectangular shape. I am using a 2.5 mm diameter o-ring glued from a cord. The depth of the groove is 1.9 mm and the groove is 3.3 mm wide.
  12. Hello again and sorry about the long silence. We returned back home to snowy Finland last Friday. I'll upload som pics when I have sorted them and adjusted the colors a little. They are very blue/green since I did not have a red filter. Sounds interesting. How are you going to shape the housing from epoxy? My o-ring groove profile is simply rectangular. This is mainly because it is milled and I did not have a bull end mill to make roundings to the bottom of the groove. But I also do not think that the roundings or the shape of the groove is very important. I really do not see how the o-ring could get off the groove when the front and rear parts are pressed together by the latches and the pressure. In some applications the shape of the groove may be important but at least in my case a rectangular groove has worked nicely. BTW. I used info from this site http://o-ring.info/en/downloads/technical-handbook/ to design the grooves. Just remember that when designing the seals for the buttons, the friction of the o-ring is larger when the o-ring is squeezed more.
  13. Just returned a couple of days ago from the liveaboard trip. The camera housing proved to be a...Tattadadaa!... Success!! The housing has been down to 35 meters with the camera and everything was working fine. Of course I did the first dives without the camera and on the very first dive I had a couple of drops of leakage at the end of the dive. I do not know where they came from but after that I did not see a single drop of leakage. The housing is not perfect, the latches need adjusting but that's difficult to do on the road so it will have to wait. There are also a couple of cracks in the back cover. It has developed cracks around the mounting holes of the camera tray because in the hurry I took too short screws for mounting it and now the screws penetrate only a couple of millimeters inside the back cover. A temporary solution to this problem was to loosen the screws since the camera tray does not have to be very rigidly attached. This reduces the stress on the polycarbonate and hopefully prevents further cracking since the cracks would soon advance to the sealing surface of the back cover O-ring. The buttons are starting to look pretty oxidized so for the next vacation I will make a new back cover and buttons. But that will take just a couple of days. For the next vacation I will also have to get a red filter and maybe a wide angle lens with autofocus. And a strobe or just a powerful light mounted on the housing. I also improvised the sunshade from a cookie box cover . I'll upload some sample pictures later when I end up somewhere where I have decent network connection.
  14. Here come the pics. Front. No dome shield (whatever it is called) yet. I will try to impovise it from a laminated restaurant menu or some other suitable plastic sheet . Back. Too bad that the buttons are not anodized and they started to oxidize immediately at the first snorkling session so they have already lost their shine. Camera attached to the back cover. Trigger button and its 3D printed extension. The grey blob at the end of the video button's rod is the one I improvised yesterday. I think I got some nice video today. I'm having some problems getting images with proper focus. I'll try to find the proper settings and upload some underwater pics too.
  15. Hell yeah! I assembled the housing yesterday evening and tested it today on a snorkling trip. Not a single drop of leakage and all the buttons except the video button work. Now after an hour of tinkering with leatherman and a lighter also the video button works. Pics later.
  16. Sort of almost in time... Spent the whole Thursday machining the buttons before I finally had to leave to the airport. Pretty much every piece of the housing is sort of ready but the housing has not been fully assembled a single time. Now we are in Hong Kong for the second day. The housing is packed in my backpack and I haven't even unpacked it yet. I hope when I put it all together, everything will work fine. We'll see about that...
  17. Dome glued, latches fitted (somewhat) and about half of the buttons turned. Still have to cut the rods for the buttons and make the dial knobs inside the housing. Plus some drilling etc. I probably won't have time to anodize the buttons and dials or to make the "lens hood" (whatever its called) but I think the housing will be operational tomorrow. Now a few hours of sleep and then back to work. Our flight leaves at 11 pm so I've still got almost a full day . Not in a hurry or anything... I just hope that everything works as planned.
  18. The polished finish looked pretty gorgeous but the only thing I can think of that could preserve it would be lacquer coating. And it probably won't stand any scratches or bumps. Maybe if I would have machined the housing of platinum... Or probably some stainless steels could withstand the salt water well enough. But then the polishing would take days instead of hours and the machining would be a nightmare.
  19. I hope I will sometime have more time to update this thread but now I really don't. Here are a couple of photos from the past few days. The body after milling. Body after about four to five hours of sanding and an hour of polishing. And the body and port after having them anodized by the professionals. The surface looks excellent and it only cost me 30 euros. Still have to make the buttons and dials. I still have two days .
  20. Yes, I think a bayonet would be much more difficult to manufacture and since I am not planning to be changing the port frequently, the screw mounting is much easier and more robust. The first tests with anodizing were not very encouraging. I did get the anodization working at least some times but since I do not have proper dyes I may not get any color to the part. I bought some food and cloth dyes and this far I have tested two of them. Did not work. 4 inch dome would be excellent for such a small housing as this. If someone knows where to get the dome, please tell me. A quick pic from yesterday. Today, I will sand and polish the body and the port and do some experimenting with the anodization process. Then I'll just need to make the buttons, dials and latch parts. And glue the dome to the port, I am a little nervous about that. If all goes well, I have enough time. If something goes wrong or does not work immediately, then I will be in a hurry.
  21. You are welcome. I think sharing more than just a couple of pics of the finished product is important especially for those who would like to do something similar. I will write in more detail at a better time but now its late again so a single pic will have to do. The past few days have been long and I have not gotten enough sleep but I hope and think that now the most difficult parts are almost finished. Today I turned the port which turned out pretty beautiful if I may say so. The surface finish you can get by turning with sharp carbide inserts is pretty amazing. A little polishing and the part is ready for anodization. The port still needs mounting holes which I will probably make tomorrow. I was planning to get the parts anodized by a professional but due to the tight schedule I might do it myself. Tomorrow I will shop around for DIY anodizing stuff; buckets, battery acid and some dyes. This way I can also anodize the buttons whenever I want to, although there is no guarantee of the quality of the results. My coworkers also take part in the costs and building the setup so that will make my job a bit easier.
  22. Good morning everyone. It's 6 am in here and I just got home after finishing machining the body. I didn't really plan on machining the whole night but that's just how it often goes; you think something takes three hours and six hours later it is still not ready. A pretty long day and night but I think the result is worth it.
  23. Damn it takes a lot of time to make these toolpaths. I spent again several hours in making the toolpaths for machining just one side of the body. Its partly because I do not have much experience in making double curved toolpaths so I don't know all the tricks and I don't find Mastercam particularly easy to learn. But there are also a lot of variables to consider when making more complex toolpaths. Below is an image of the Mastercam program with the almost ready toolpaths in blue. It doesn't help making the toolpaths that everything has to be perfect. If I ruin this part, it will cost me 40 euros in material, and a day in time, which I really wouldn't like to loose. Also, the carbide cutting tools are not exactly cheap and they can break if you run them too deep or too fast or into the table. Tomorrow is going to be a full machining day again. I hope to get the body ready but I seriously doubt that. I will also need to start machining the port tomorrow or at the latest on Wednesday so I can get both parts to anodization on Thursday..
  24. Here's a step by step story of machining the inside of the body. I always enjoy machining pics, I guess there must also be others with this kind on personality disorder. Here is where the machining starts; a rough 3½ kg billet of aluminum. Of course before starting, the milling paths have to be made (took me like 5 hours for this part) and the tools have to be set up. The milling process itself takes less than an hour. First, the billet is machined to as precise as possible a rectangle with the desired dimensions. Now when the orientation of this rectangle is changed and it is clamped, it will always be accurately in the desired orientation (as opposed to the initially not-so-rectanglish billet). Then, the back cover o-ring groove is machined with a 2.5 mm end mill. Next the main job i.e. digging the hole for the camera with a 12 mm flat end mill. The middle part is for mounting the part during future machining steps. This was as pretty messy part of machining since the pit was full of cutting fluid and I had to empty the chips from there with pressurised air. There were chips and fluid everywhere within 3 m radius of the machine. Then finishing the sides and chamfers with a 14 mm ball end mill and some pockets to the bottom with 8 mm flat end. The tools had to be long so they vibrated a little. Therefore, I did not get exactly the surface finish I wanted. I guess I will sand also the inside of the housing if I have time. That was pretty much it for now. The worst part is always the cleaning. This time it took about an hour. It seems that half a liter of solid aluminum turns to quite a large volume of chips. At times like these I really love our industrial vacuum cleaner which can handle the chips and the cutting fluid.
  25. It's 2 am in Finland and my machining weekend just ended. Did not get as much done as I had hoped for but the housing is starting to take its shape. Here are the results this far. More pics to come but now is not the time to write long posts... Yes I have also been wondering why am I even doing this, especially now that my schedule is tight and I know there will be long days, evenings and probably nights of machining ahead. Probably it is a symptom of some mental disease. I think I also just want to prove to myself that I am able to do this. The pressure in 30 meter depth is about 400 kPa and inside the housing the pressure is 100 kPa so 300 kPa pressure difference.
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