Luminous Landscape Forum

Equipment & Techniques => Medium Format / Film / Digital Backs – and Large Sensor Photography => Topic started by: Cineski on November 10, 2011, 01:56:41 pm

Title: Contax 645 lens hood plastic ring replacement
Post by: Cineski on November 10, 2011, 01:56:41 pm

Anyone have a line on the plastic ring that inserts into the Contax 645 lens hoods (the part that actually touches the lens)?  I found a cheap GB-72 hood but the ring is broken.  I could probably fix it with CY glue but I'd rather get a replacement if possible.  Thanks.

Just got an email back from Tocad and this isn't something they carry.

Title: Re: Contax 645 lens hood plastic ring replacement
Post by: Cineski on November 14, 2011, 06:40:44 pm

Okay!  Part II:  What's the best type of glue to use for plastic for this type of situation?

Title: Re: Contax 645 lens hood plastic ring replacement
Post by: Harris Edelman on November 14, 2011, 10:35:38 pm

The plastic looks like ABS. To be on the safe side, I'd ask ToCAD to confirm that.

ABS is soluble in acetone. Carefully apply acetone to each side of the break, press together, and in about 5 minutes the weld should be stable. This would be stronger than an adhesive bond.

Naturally, you'll approach this at your own risk. Before you repair the lens hood ring, you might want to familiarize yourself with the action of acetone as an ABS welding agent by working with some scrap ABS pieces. Good luck!


-H.

Title: Re: Contax 645 lens hood plastic ring replacement
Post by: baudolino on November 15, 2011, 12:14:06 am

be careful with the glue - some glues emit gases that can fog your lens (there was a thread about this on another forum recently)

Title: Re: Contax 645 lens hood plastic ring replacement
Post by: Cineski on November 15, 2011, 04:58:42 pm

Interesting.  Have a link on that thread?  I searched via several ways and couldn't come up with it.