Film-Tech Forum ARCHIVE: Replacing B&H worm gear , 16mm projector

This is topic Replacing B&H worm gear , 16mm projector in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

To visit this topic, use this URL:
https://ft-forum.com/ft/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=012349

Posted by Jonathan Wood (Member # 4614) on 09-30-2018, 12:27 PM:

Hi all,

I’m looking for a bit of advice from those knowledgeable on 16mm machines .

I’m pretty happy tinkering with 35mm but I’ve not much experience fixing 16mm. My question is , how feasible is it to replace a worm gear yourself or am I opening myself up to a world of frustration and pain ! The machine in question is a TQ1, old I know but in otherwise immaculate condition and so much better built than the later plastic ones .

I’ve got several old mechs that I’ve practised on and removing and replacing the gear itself , although fiddly , isn’t my main concern. I’m more concerned that I’ll never get the timing right . Unfortunately the original gear has disintegrated so I can’t make any marks to line things up with after reassembly. I know there are people here in the UK who offer this service but I’d kind of like to have a go myself but not at the expense of ruining the machine . Any help or advice will as ever , be gratefully received! Jon

Posted by Abraham Robinson (Member # 10230) on 10-01-2018, 10:59 AM:

you should post / look through the threads on 16mmfilmtalk.com - lot's of useful info on B&H worm gears there

Posted by Scott Norwood (Member # 30) on 10-01-2018, 11:30 AM:

As I understand it, this is a difficult repair because B&H machines require a number of alignment and calibration tools in order to re-assemble them properly. If you have the tools and the service manual, then it is probably fine to attempt. If not, it is probably best to find a camera or audio-visual repair service that has the tools and expertise to do it properly.

The other problem is that, unlike 35mm machines, these 16mm portables use tiny parts. Depending upon your dexterity, this may or may not be a problem.

Posted by Jonathan Wood (Member # 4614) on 10-02-2018, 02:47 AM:

Thanks guys , yes the general opinion seems to be it’s too tricky unless you really know what you’re doing !

Posted by Leo Enticknap (Member # 534) on 10-02-2018, 04:59 AM:

There was a place, in Lincolnshire if memory serves me correctly, that was making new steel worm gears, either for sale for DIY installation, or a swapout service. This struck me as a much better idea than using plastic or bakelite, which are probably going to chip or crack again, sooner or later. I've just Googled, but can't find them.

As Scott points out, you need expertise, patience, and some very specific tools. That is why I've always preferred Eiki 16mm portables - their modular design means that pretty much anything that can go wrong with one can be fixed by a DIY-er.

The B & H worm gear represents the nightmare combination of a part that is both life-limited and a huge pain to replace.

Posted by Mark Gulbrandsen (Member # 72) on 10-02-2018, 09:57 AM:

For pittance that 16mm projectors go for these days I wouldn't even bother to replace it. But I would replace it with an Eiki or Kodak just because they are very serviceable...

Mark

Posted by Emiel De Jong (Member # 4225) on 10-03-2018, 01:23 AM:

This webshop in the Netherlands offers their self made parts:

https://www.van-eck.net/itable.php?lang=en&size=0&cat=film&merk=15&type=Filmosound%20TQI%20(model%20652)

Posted by Bill Brandenstein (Member # 7758) on 10-03-2018, 05:28 PM:

...which is impressive as they offer both the still and non-still versions, 3D printed. (Nice work as always from Edwin.) Urbanski has both now, too. My 2592 is now a 2585 because the still function worm gear was unavailable just a few years ago when my machine was rebuilt.

Not sure how 3D printed material and Urbanski's "long life black plastic" compare, but I'd jump on either of these in a heartbeat over a new-old-stock original vinyl gear that's just going to split open again.

Somewhere along the line Gary Hoselton published a document detailing the awful and convoluted process of how to replace the worm gear yourself. He can be found at 16mmfilmtalk.

Posted by Gary A. Hoselton (Member # 3447) on 10-20-2018, 07:38 PM:

Replacing the worm gear isn't that hard to do, just must be careful and organized. Entire mechanism can be removed from mainplate, can rebuild in situ or remove to mount in jig. An older machine should come apart anyway, so as to clean and lubricate and adjust everything. I'd use Larry Urbanski's worm gear with the black plastic surface, I'd guess it is Delrin AF which is quite stable. I'm not sure about a metal surface worm, as mechanism was designed for plastic-plastic gear teeth interface.

Older B&H have solid case and all, but have much more stuff in them to get in your way. I'd recommend the last B&H, 2585 and 2592 in the U.S. If a 2592, which has the pause function, I'd eliminate it by using regular 2585 worm gear and remove the extra parts--they just get in the way of servicing the mechanism and we wouldn't dare use stop-motion for fear of damaging film.

If you want my overhaul procedure, email me and I'll send file to you. Have fun!

Posted by Monte L Fullmer (Member # 2797) on 10-24-2018, 06:08 PM:

I'm more concerned with the shuttle claw, being these will eventually get a notch at the base and underside of the tooth on the pulldown and it's good bye for steady image.