Film-Tech Forum ARCHIVE: Dreaded B&H 16mm worm gear

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

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Posted by Jonathan Wood (Member # 4614) on 02-19-2018, 06:06 AM:

Hi guys and gals, i Was wondering whether anyone knows of anyone in the UK who can replace worm gears in late model 2582 16mm filmosounds? I have a replacement gear and I’m half thinking of doing it myself , I know it’s a major pain on these machines and without the jigs for reassembly , how likely is it I’ll succeed ?! I’m pretty competent electrically and mechanically (well in my opinion anyway !) thanks as ever

Posted by Gareth North (Member # 3542) on 02-20-2018, 11:18 AM:

Hi Jonathan,

Funny I just happened to check the Film-Tech site and find a fellow Brit needing the dreaded worm gear fixing having only just had mine done on my 2585AX. The guy i'd recommend is Kevin Brown based in Nottingham his business card shown below.

He used to have a website but like a lot of the older guys cannot be bothered with that kinda thing anymore. I got mine fixed by him early December. He's based in Nottingham which was easy for me to drop off! His hallway was filled with projectors that he's been asked to repair he was working on some double projection system thing (audio 16mm one side 16mm picture the other) when i dropped mine off.

As well as him fixing the worm gear he put all brand new belts on mine. Fixed the Framer that only moved up and the autoload lever not staying in place when loading. He also retensioned and reoiled the whole thing and made it like a whole new machine! I never really knew what these things were supposed to sound and run like until he looked mine over. I can't recommend him enough.

By the way your not the Jonathan Wood who produces all those perfectly scanned network DVD releases of classic ITC shows per chance are you?

Best Regards

Gareth North

webmaster of
bolexh16user.net

Posted by Monte L Fullmer (Member # 2797) on 02-20-2018, 03:44 PM:

I'm also wondering on the shuttle pulldown assemblies being if any new shuttles are still available for these B&H units along with any shuttle based projector, in any 8, 9.5 and 16mm projector.

Posted by Jonathan Wood (Member # 4614) on 02-20-2018, 04:37 PM:

Gareth , thanks so much for that . I’ll drop him a line as the more I think about it, the less I want to try and do it myself! Now you’ve mentioned his name ,I seem to remember hearing about Kevin a while ago but he’d slipped my mind,so cheers for that.

No, I’m a different Jonathan Wood but I am a big fan of Network’s stuff !

Thank, Jon

Posted by Steve Kraus (Member # 476) on 02-20-2018, 07:39 PM:

Monte, yesterday I broke up a 1575A slot loader that wasn't worth repair. These machines have intermediate gears between the one lower one driven by the infamous worm and the lower sprocket. (Do the others?) Mine was cracked and while I thought my worm was still good I could see it was starting to crack as well. This was a hamfest purchase for, I think, $15 so no worries about junking it. I saved the lens, BHB bulb & socket, motor, amp, slit lens & solar cell and also the reel arms. I pitched the rest.

The shuttle & claw, shutter, gate & trap and that stuff are still intact as part of what I call the sub mechanism plate. If you think that could be useful to you let me know.

Posted by Gary A. Hoselton (Member # 3447) on 02-20-2018, 10:25 PM:

Johnathan, I've written an overhaul procedure for B&H25xx projectors, which would give you some background. Provide your email address and I'll send it to you. Larry Urbanski, near Chicago, is reproducing three calibration gauges, including sprocket timing, and his work is nice. Regarding the worm gear, when the 5xx projectors were designed in the middle 1960's, nylon was in vogue. All production 5xx-25xx have them. We've since learned that nylon shrinks and becomes brittle with time. The replacement gears are made with what looks like a Delrin surface, dark brown so perhaps Delrin AF, and that is a stable plastic.

Agreed, I wouldn't put any effort into a B&H slot load projector. They were cobbled from the autoload so to not lose sales to school customers who insisted on slot load, and contain too many compromises. I like autoload, have two 2592's in manual changeover which I run several times a week.

Posted by Gareth North (Member # 3542) on 02-21-2018, 05:05 AM:

Hi All,

Glad I could be of help Jonathan! Definetly let Kevin know I was the one who recommended you! Its also worth noting that there are new worm gears out there that for some reason do not work correctly when used with Bell and Howells. Maybe they were made for some other purpose but Kevin has had people in with projectors fitted with these look right but not function right gears and had to replace them.

While we are on the rare subject of 16mm Bell and Howell projectors does anyone know how many various designs of short throw lenses are out there for them? I've had my gate extended to show the full Super 16mm image so I can project all my Super 16mm shot material. The lens mount has not been recentered and I have found the following lenses work fine on it without recentering:-

The Standard Lens you get with a Bell and Howell with or without filmovara attached
The Later Model Japan Zoom Lens F1.3

But i could do with a short throw lens that works with the Super 16mm format, so I bought a Buhl Optics 0.625" (f1.6 i think) short throw lens but it vignettes fairly bad on the right side. This lens is a bit bizarre in the fact it consists of 2 lens elements (rear lens pupil + Front Lens) and both lens elements can be unscrewed from the barell mount. So i could get my camera engineer to construct a new lens barrel to hold / recenters these uncrewable elements but he'll charge $$ to do so. So I wondered if there are any other short throw lenses maybe f1.2 that might have a different design that I could try that might not vignette like the Buhl.

Also has anyone ever ordered test film from the French version of the SMPTE in Paris called CST? I could do with 100ft of there Super 16mm test film for ruling some other things in and out with regard to my projection but had no reply from emailing them and I don't speak French:-

https://www.cst.fr/produits-et-services/mires-film/

Best Regards

Gareth North

Posted by Steve Kraus (Member # 476) on 02-21-2018, 10:07 AM:

Perhaps remove and junk the elements of a standard B&H lens and install a small barrel lens intact within it. For example I have an ancient DeVry in storage and the lenses for it were about 30mm in diameter. That might be an easier solution since less precision work is required.

If you took a B&H lens (about 2" diameter), to do it neatly one would machine away the entire rear of the lens but precision is not required and one could simply cut it away with a saw or cutting wheel on a Dremel. Then drill and tap 8 or so holes in around the barrel in which are placed long Allen keys to hold the small lens straight and centered but sufficiently off center for Super 16. A lot of trial and error fitting would be needed but once correct would need no further adjustment.

Posted by Mark Gulbrandsen (Member # 72) on 02-21-2018, 12:01 PM:

I don't understand why anyone bothers with these machines. They were just ok projectors when they were new. Eiki's are far easier to repair and are much gentler on film.

Fact. You can tear down and Eiki and reassemble it in under two hours.

Mark

Posted by Jonathan Wood (Member # 4614) on 02-21-2018, 12:36 PM:

I agree with you Mark that Eiki’s are far easier to work on than B&H’s but the one reason people might still need B&H is the greater availability of lenses for Them. I may be wrong,but wide angle or zooms for Eiki’s are rare as hens teeth these days whilst there’s still a lot about for B&H. The only reason I need my B&H is that I need to fill a screen at a public show and given the throw my (far superior IMO) Elmo with its limited lens range , wont do the job. Jon

PS : Gary, I PM’d you , thanks again , Jon

Posted by Mark Gulbrandsen (Member # 72) on 02-21-2018, 01:12 PM:

quote: Jonathan Wood
but the one reason people might still need B&H is the greater availability of lenses for Them.

Its pretty easy to machine a lens barrel to adapt other lenses to Eiki. If you can;t machine one a local shop could easily do it and probably for not a lot of money. I tend to prefer the Schneider 16mm zooms myself. They are adaptable to Eiki.

Mark

Posted by Jonathan Wood (Member # 4614) on 02-21-2018, 01:30 PM:

True enough- I meant to add that re housing is an option , but I was in a bit of a hurry . I’ve always thought EIKI and Elmo lenses to be superior to B&H ones , sharper and a bit cooler .

Posted by Ian Partridge (Member # 9377) on 03-12-2018, 10:33 AM:

I agree the infamous Bell & Howell cracked worm is a popular problem and I will recommend Kevin Brown of Nottingham. Also, there is Nigel Lister of East Bergholt, Suffolk who is an excellent cine technician.

I was supplying new 'old stock' replacement ones to UK and overseas, until they ran out. Someone had found a couple of dozen in his late fathers' shed and sold them to me having googled my cracked worm information page. These were the solid grey/black plastic non-animation ones. Since they ran out I have been recommending Edwin Van Eck's 3-D printed ones.

It seems that it was the thinness of the nylon outer worm shell on a metal core that caused the cracks. Possibly due to unequal heat expansion of the nylon outer and inner metal core when the projector is running, and including heat from the lamp. The large upper and lower sprocket gears also are nylon engaging with the worm gear.

Ian