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T.J.L.

Member Since 28 Dec 2013
Offline Last Active Apr 12 2014 10:54 AM
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Posts I've Made

In Topic: DIY housing for E-M5

12 April 2014 - 05:26 AM

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 :).


In Topic: DIY housing for E-M5

28 March 2014 - 02:17 AM

Those pictures look good, regarding it is a DIY project ! I would suggest building

flash housings before your next trip. ;)

 

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...


In Topic: DIY housing for E-M5

22 March 2014 - 06:32 AM

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.

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Samyang, the brand nicely visible in reflection. I'd suggest covering any white text on the lens :).

_2100933.JPG

 

Panasonic 20mm. Corners are quite soft.

_2110472.JPG

 

 

Panasonic 20 mm.

_2110616.JPG

 

Some macro with Samyang.

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In Topic: DIY housing for E-M5

19 March 2014 - 06:38 AM

Hi, I am doing negative mould. So first model from polystyrene (finally done, which was, I guess the worst part, especially from surface smoothness perspective). Next step will be the mould itself and the housing. I will definitely post whole process here incl. pictures. Regarding the groove: I meant opened housing....If the o ring stay in groove or comes out with opening a than has to be adjust again.

 

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.


In Topic: DIY housing for E-M5

17 March 2014 - 06:46 AM

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.

 

GREAT JOB...I am just in the beginning of similar project (not so sophisticated of course - like FEM etc:)), but different material (epoxy resin) - for GH3 and G6. The issue I am facing now is the groove for o-ring (connection between front and rear part). What profile did you use? Is it perpendicular to case body axis or slanting (to stabilize the ring at position). I have a concern the ring will get off if the groove will be without "inclination" Looking forward to outcomes of your pics....

 

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/e...nical-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.