Polycarbonate housing durability/what might cause housing cracks?

I recently noticed small radiating stress cracks around one of the controls on my Ikelite D70 housing, on inspection there was another, larger, crack on the side of the housing. Water had entered, presumably through these, but fortunately the camera and housing electronics do not seem to have been damaged. The housing is currently being repaired by Ikelite, promptly and at minimal cost (thanks Ikelite!). However, they have been unable to shed any light as to what might have caused the cracks, I was wondering if anyone had any suggestions.

I have had the housing 2 years and it has done approx 200 dives, mostly in the 20-35m range, the deepest to 46m - well within the depth limits for the housing. Most of the diving has been in temperate waters so the hosuing hasn't been exposed to extremes of heat and cold. The housing has not been knocked, to the best of my knowledge, and is kept in a protective wooden box on the dive boat. I follow all the usual housing care proceedures - making sure to rinse well after dives etc. I have flown with it but always carrying it as hand luggage.

I notice from the forum that others have had similar problems. Does anyone know why these cracks might occur? I have been happy with the Ikelite housing until now but this has made me wonder if it is simply not durable enough for my sort of diving (although I wouldn't have considered the usage excessive). Does anyone know how long polycarbonate housings last, or have a particularly long lived one? One of the main reasons for choosing Ikelite was the lower price - should I be looking to remortgage and upgrade to a metal housing? Is there anything I should be doing to protect the polycarbonate housing from the same thing happening again?

Any advice much appreciated,

Thanks,

Claire

Case a bad luck? Be glad you have a responsive and customer friendly vendor to deal with the problem! Have you ever traveled by air with the housing sealed shut? Ever use any questionable lubrication products on it?

I've had an Ikelite D70 housing since June 2004 and have probably taken it on 250 - 300 dives. I have not seen any problem like you describe with your housing, and I honestly can't recall a similar complaint on any of the discussion boards. I've killed a few sync cords, but that's about the extend of the problems I've had with my housing.

Personally, I like the polycarbonate housing, and I find it useful to be able to see inside to ensure o-ring seals, hot shoe connections, camera switch settings, etc. I'll probably stick with Ikelite when I upgrade. I think they make great products, support them well, and provide excellent value. I could afford a much more expensive housing, but I have yet to be convinced that they provide much benefit. (Ok, I suppose the $1000 viewfinders are pretty sweet...)

Dave

I agree it may be just bad luck.

I have two Ike housings one is nearly new but other I bought second hand and is about 4 or 5 years old. The older one has been on several hundred dives with me which added to the dives that the previous owner did with it makes it a well used housing. I can see no cracks.

The controls on the older one can be quite stiff after a long dry period but I have taken them apart occassionally inspected them for corrosion and then lubed them.

Keeps us updated as to what Ike says.

Martin

I think the only thing that would cause this would be physical stress...

We have one of the first original Canon Digital Rebel housings, with hundreds of dives to depth. Has been serviced by Ikelite several times, upgraded a few (TTL, Angled bulkhead, etc), but no issues. We travel everytime dive living in Missouri so pack it alot. Also have a Ike housing for the 20D same deal, no issues and couple years old.

I have had great service from Ikelite and our dealer (Ryan) over the years. Hope all works out well for you.

Dave

Thanks for the reassurance everyone, nice to know that there are some long-lived polycarbonates out there. Have my new housing from Ikelite now (they replaced the whole front of the housing) so am hoping that was just a problem with that particular one.

Best wishes,

Claire

My previous Ikelite housing, for the Nikon 8008, developed a crack after about 8 years and 500 dives. The crack was a point failure on the face of the housing. Ikelite replaced the housing piece for a nominal cost. I asked the service tech I dealt with about possible reasons for the failure and he said somethng like "It happens" but not often. The only known possible damage to the housing was when a diver on a boat knocked my whole rig to the ground with a bag he was carrying around - but the failure did not occur for at least 30 dives after that (maybe more). There was no obvious impact at the failure point either.

So, maybe it just happens.

I think there have been discussions in the past about certain types of solvent that could potentially damage the polycarb housings but you might need a plastics expert to find out more (or try contacting Ikelite).

My current Ike housing shows no signs of cracks and the replacement didn't either.

I work with plastics all the time at work designing molded parts. Although polycarbonate is one of the toughest plastics there are a few things to keep away from it. Never use Windex or glass cleaners as they contain ammonia. Organic solvents and degreasing solutions should be kept away. A sure sign that some of the chemicals have come in contact with your housing is grazing. Grazing is when the plastic starts taking on a white hazy finish or starts to loose its transparency. These checimals can also make the plastic brittle around openings. The other possible reason for cracking could be processing during the molding process. Injection molding plastic comes in a pellet form which must be dried before molding. Plastic not dried correctly before molding can degrade the final product, before quality control usually spots this problem with proper testing.