I've A Screw Loose.

Dale.

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Dale.
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Completely gone actually.

My Sigma 150-600C has been a workhorse and has given faultless service this last 4 years. Last week though, I was putting my camera and lens back in its bag afer a session with the Kingfishers. I noticed that the hood mounting ring had slipped forward slightly, I could see the brass innards below it. I pushed it back into place and thought no more of it.

I was out again yesterday and got soaked in a very heavy shower. I packed my gear away before it got soaked too, as while the 5D is weather resistant, the Sigma isn't, being the C. When I got home, I let them both dry out, not that they were wet, just a few drops. Today, I decided to check and clean the camera and lens and I noticed the lens hood mounting ring had slipped forward again and it was actually loose. I noticed that a small grub screw was actually missing and this was the cause. There is no chance of finding that screw, it could be anywhere and it is tiny.

Now I'm trying to find the screw size/thread etc but I can't find anything online. I've looked for a spare parts list and nothing has come up. I have found a screw that fits, threadwise, from an old lens I dropped and I kept it for spares. The screw is too long though and I'm not wanting to risk it as it could potentially crack the front glass.

Anybody else had this with their C and did you manage to find a screw/supplier?

I'm thinking I may have to contact Sigma UK. I love the lens and want it right.

TIA.

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The head will be JIS, sorry I can't help with the pitch or length.
 
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I can't find my measuring gear, I can measure it properly at work tomorrow but thread looks like M1.5, 3mm long, pentalobe 1.2 screw head, looks like a Sigma special.

Edit, typo M1.6
 
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Flippin eck Gav, that's above and beyond, dismantling a lens to help out.:LOL:

Thanks for the info Bud.
Trouble having OCD and being a precision Engineer :LOL: No worries

It does look like a low profile 'anti tamper' screw
 
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Dale, could you cut the screw you have with some side cutters and file it clean after? Fiddly I know, but do able if you have needle pliers
 
Another suggestion for contacting Sigma. They are very good. They may give you a replacement screw or ask you to send it to them.
 
Didn't stop Dale tampering with it! :LOL:

:coat:


Wasn't me, honest. :angelic:


Dale, could you cut the screw you have with some side cutters and file it clean after? Fiddly I know, but do able if you have needle pliers

If it comes to it, I will Gav. The one I have is about 6mm long.


Another suggestion for contacting Sigma. They are very good. They may give you a replacement screw or ask you to send it to them.


Yes, (begging) email heading thier way tomorrow. (y)
 
Feel free to shout if you need it measuring up properly (y)
 
I have had this happen. One screw missing and two loose. I found a screw on a Pentax lens that fitted well. The two loose screws have neither a slit head nor a cross head and I struggled to tighten them- I used a kitchen knife blade in the end.
 
Morning @Dale.

I need my eyes calibrated, I miss read my rule by 0.1mm :LOL:

M1.7 thread
3mm Dia head x 0.5mm low profile head 1.2 Pentalobe
3.3mm overall length (2.8mm thread length)

Long shot, any phone/PC repairers near you? Mac/Iphones may use the same, I can't check, I'm Android user
 
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The little screw that holds the hood on my Sigma 150-600mm Sport went missing some years ago, I contacted Sigma and they just sent a new one out for the price of the postage.


Cool.

I sent them an e-mail earlier today. Must be a common problem.
 
Well, that was unexpected.

Contacted Sigma late yeasterday via e-mail. Reply waiting for me this morning, asking for my address. Screws will be on their way tonight and no mention of any charges.

Can't fault that at all. (y)
 
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