8mm Forum: Bell and Howell 1698 speed problem

This is topic Bell and Howell 1698 speed problem in forum 16mm Forum at 8mm Forum.

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Posted by Chris Bird (Member # 3839) on October 16, 2018, 02:39 PM:

At the Chorleywood fair a couple of weeks ago I purchased a green Bell and Howell 1698, with the worm already replaced, for a very good price.

Unfortunately, all is not well. The sound is muffled, but more importantly the machine seems to be running slow. I compared a reel on both this new machine and my trusty black 1695, and the difference was noticeable, probably around 2 fps I would judge, ie I think the 1698 is running at around 22 fps.

Obviously it may need a trip up to Kevin Brown to get it all to rights, but one thing that puzzles me is that the voltage on both my machines is set to 250v, not 240v. Is that right? Though given the 1695 sounds fine, I guess it must be ok. I just wondered if it would account for the speed problem.

Sometimes, a machine is cheap for a reason.... Though given the worm has been replaced, it may be worth spending the money to have it all properly serviced. Assuming it's not one of the worms that's a fraction of an inch too large, which Kevin has warned me about, which would mean a ton of work needs doing to replace it again.

Out of interest, it has a sticker on it labeled 'Penrose Cine' from Streatham Hill, London, who may conceivably have carried out the worm replacement. I've not come across them before.

Posted by Maurice Leakey (Member # 916) on October 16, 2018, 03:12 PM:

Chris
Muffled sound could mean dirty optics. Is there not a setting for 240 volt?
Penrose Cine is a name from the past. So old that it's unlikely they would have had the worm changed, its only in these later years that the worm problem surfaced. No doubt they were the original suppliers.
A good idea would be to give Kevin a phone call
https://www.yell.com/biz/kb-cine-repairs-nottingham-8723722/

Posted by Simon McConway (Member # 219) on October 19, 2018, 04:45 AM:

I'd check the rollers that hold the film tight around the sound head drum. These should snap back to the closed position when raised by hand. If not, go to the back of the machine, note where the backs of the arms are that hold the rollers, and add a small focused spray of oil to help free them. Feel free to catch up with me at Harpenden this weekend.

Posted by Chris Bird (Member # 3839) on October 20, 2018, 07:14 AM:

Hi Simon, the rollers seem fine. I'm afraid I can't make Harpenden for the first time in years as it's my parents' 50th anniversary and they're having a party.

Maurice, I had a long chat with the excellent Kevin Brown, and he says there are ways of adjusting the speeds inside the case, so his theory is that these have been knocked out fo alignment at some point. He says the voltage selector won't make a difference to the speeds, but that it should be set to 240v not 250v.

I'm sending the machine up to him next week for a proper check over.

Posted by Maurice Leakey (Member # 916) on October 20, 2018, 10:03 AM:

Good for you, Chris.
Perhaps the two speed pots have been messed about with by someone not qualified.
I am sure that Kevin will give your projector a thorough going-over, as he always does.
I will shortly be collecting my two Bell & Howell 655 TQI which he has brought up to modern standards with new worms and ELC lamp conversions.

Posted by Chris Bird (Member # 3839) on November 03, 2018, 03:44 AM:

An update on my 1698. The projector has now arrived at Kevin Brown's and he has checked it over for me. This may be a useful cautionary tale for others. While the machine has had a new worm fitted previously, it is one of the dreaded ones which are a fraction of an inch too large. Kevin says that over the course of a feature film it would heat up, expand, and potentially jam the mechanism.

Whoever fitted it also got the timing wrong, so that the loop restorer would function while the claws were still engaged - ouch.

Kevin is going to put all this right for a very reasonable price, as well as fitting a three bladed shutter and a varispeed feature so that the machine can run at any speed (very useful for the silent films I mostly collect, which are shot at a variety of speeds rather than just 18 or 24).

But the moral is don't assume that because a B+H has a new worm that it has been done right by someone who knows what they're doing! To fit a replacement worm correctly is definitely a job for a skilled professional with the right tools and jigs.

The machine was cheap to begin with, so I am not unhappy overall, and will end up with a fine machine at the end of it.

Posted by Dominique De Bast (Member # 3798) on November 03, 2018, 04:02 AM:

Chris, the voltage set to 250 v doesn't affect the speed (due to the kind of motor of "recent" machines) but the brightness of the light. Projectors are (or more correctly were) always set to the next higher voltage than the current one to protect the bulb. I assume the voltage in the UK is 230 v as on the continent so if you can set your projectors at 240 v, it's better.

Posted by Maurice Leakey (Member # 916) on November 04, 2018, 01:49 PM:

Chris
When Kevin has finished you will have a projector to be proud of.
Those awful worms do keep turning up, and as you say, a newly fitted worm is no guarantee. Unless, of course, it's one fitted by Kevin. [Big Grin]

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