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Posted by Craig Crane (Member # 908) on October 05, 2007, 05:38 PM:
 
Having recentlty aquirred an Elmo ST 1200, I would like to know if
the shutter wheel is meant to have a rubber belt around it, and would the lack of one introduce a lot of flutter.

Secondly, what would be the main cause of slow playback. Set at 24 fps it actually sounds like 18, and set to 18 sounds more like 12.

Belts?

Dodgey motor?

Its turning out to be a horrendous ebay experience, and hope that a refund will follow as its clearly not in working order. But if you could shed some light on the above issues I would be most gratefull.

Happy to post images and video in the morning if that may haelp.

C
 
Posted by Mark Todd (Member # 96) on October 05, 2007, 05:59 PM:
 
Hi Craig, some have the rubber on, some do not. If you get a refund, next time ask if it has the rubber on the shutter edge, if it does leave it unless very cheap.
It could very well need a new set of belts, when you buy projectors they often do unless its from an enthusiast who mentions they have been changed recently.
Is the rubber on the shutter edge soft and sticky that could be causing the speed probs, if not could be something ro do with the rubber drive wheels.
You can remove the shutter rubber a bit awkward, carefully and the machine will play at 23 odd FPS not quite 24 but OK. But the rubber drive wheels ( that run on the shutter flat edge) have often gunked up too or from that.
Tom on here sells the last few of those available.
Theres hope for the machine but you should have been told etc.
When did you buy it?????
I`d hold out for a refund.
Every super 8 projector or even 16mm made has an achilies heel or two but this is a serious matter you need to be informed of.
Don`t let it put you off there are plenty of good machines about and one or two will come your way before long and much fun should ensue.
Very best wishes and good luck.
Mark.
PS Kevin F can give you a run down on how to tackle the rubber on the shutter or it may already be here somewhere on the site.
 
Posted by Gary Crawford (Member # 67) on October 05, 2007, 08:43 PM:
 
Craig....I recently got an st1200D off ebay...fairly cheap... the rubber on the shutter wheel.. the belts..everything rubber was nothing but black goo. 27 u.s. dollars worth of belts and a few minutes scraping the gooey rubber off the shutter wheel..and a bit of cleaning off the old grease on the gears..and putting some new grease on ...and I had what
amounted to a brand new projector. worked beautifully. Many of the st 1200' s can be revived fairly easily , even for a non tech person like me.
 
Posted by Craig Crane (Member # 908) on October 06, 2007, 04:17 AM:
 
Thanks guys.

This shutter wheelhas no rubber on it, and the belts are like warm liquorice... I ran a old test reel last night and it was just painfully slow.

The edge of the shutter wheel does not look like it has ever had rubber on it.

Heres the rub though, of the three super 8 units I have brought on the Bay this month, all of them have had issues.

The least being a damaged take up reel on a S 905 GL (but I dont use it as its noisy and I dont like the way the reels layout.

A Eumig s 934 looked perfect on the surface, but when I opened her for a deep clean, the large metal body inside had what looked like a white powder type corrossion on it that I now need to get rid of as this could fall of and settle in the gate..... beed I say more?

And then the 1200. This looks like it took a knock in transit. It was shipped in its original black carry box, with nothing more than a thin cardboard box surrounding it. Its carry handle was expossed to ease carrying for the courier, but that looks like that may have been an impact point as its shattered. As was the take up reel included in the box.

The sound circuit has a ground loop hum all the time, even through headphones.

Optically its fine, and a marked improvement over my others, but whats the point when playback is marred by wow & flutter.

I have ordered some new belts from a supplier on E bay. Although advertised as being for the st1200, classic home cinema in the UK has since told me that these are not specifically for the machine. They are just a size match.... Another 15 quid down the drain???

Whats really p*ss*s me off though is the fact that I have nothing but good luck with the films I have purchased.

Ironic that I as yet dont have a glorious st1200 to play them on.
 
Posted by Mark Todd (Member # 96) on October 06, 2007, 04:51 AM:
 
Hi Don`t panic craig the belts should sort it, even if not elmo type as such they will work fine.
The machine should come round to being a good one with the odd fiddle and the fact that you got one with no rubber on the shutter edge is major plus.
Classic are good for projectors as are perrys or P Foster etc.Often in terms of value better than one from an ebay no idea seller.
But as I say the 1200 will be great once the belts are on and run a while it will settle with luck.
Best wishes Mark.
PS keep the faith it will all get great.
 
Posted by Kevin Faulkner (Member # 6) on October 06, 2007, 05:07 AM:
 
The hum is probably down to the Hum Buck Coil out of adjustment. Very common on these machines. You should see a small yellow coil underneath the sound heads.

With the machine running, with the lamp on move the coil gently to a position where the hum is minimum.

Yes slack belts can certainly cause slow speed and make sure the belts are on correctly. The belts can be put on in a 50 or 60Hz position.

Make sure that all cogs are running free and that the grease hasn't dried out and gone hard. Also give he pinch roller a good clean with Isoprop to make sure the film isnt slipping at that point which would also introduce wow.

I think you will find that all will be fine after the belt change. As mark says providing the belts are the correct size they should be fine.

They are great little machines and seem to go on year after year.

Kev.
 
Posted by Craig Crane (Member # 908) on October 06, 2007, 05:24 AM:
 
Thanks guys.

I gave the heads a clean last night.

Phew... they were dirty! I mean really dirty.

Takingthe back off,the belts are set for 50hz, which is ideal. I shall hold of on the grease till I try the new belts. We have a postal strike here in the uk at the moment, so its all just a matter of waiting. Classic shipped a nice 1200 aluminium metal spool and a spare lamp, so its all coming together slowly.

Now, back to the grease..... is there a particular grade I should use, or just a generic grease for gears?

C

PS: Classic and P Foster are great. Cant fault them in any way. Not tried Perry's yet.
 
Posted by Bart Smith (Member # 780) on October 06, 2007, 03:29 PM:
 
quote:
Also give he pinch roller a good clean with Isoprop to make sure the film isn't slipping at that point which would also introduce wow.
Kevin - Whilst I appreciate that your knowledge of Elmo maintenance is generally second to none, I have to take issue with the particular advise that you gave above. Cleaning a pinch roller with IPA is more likely to exacerbate slippage and wow in the long run than it is to sort it out. IPA is NOT the correct cleaning agent to use: it will damage the pinch roller, eventually causing it to harden, become more slippery, and ultimately crack the outer surface. Proprietary rubber cleaners are available from specialist suppliers (search for Platen cleaners - these tend to be the correct formulation) - if you can't find these readily or need an easy solution to your problem, a mild detergent solution (e.g. washing-up liquid) and cotton buds is very effective. Wash it off afterwards with good old tap water.

DON'T USE ISOPROPYL ALCOHOL ON YOUR PINCH ROLLER!!!
 
Posted by Kevin Faulkner (Member # 6) on October 06, 2007, 03:57 PM:
 
Sorry to say Bart that I have used IPA for as long as I can remember and to date have not had a single problem.
I would also like to point out that many tape machine manufacturers sold IPA as tape path cleaner and some cassette manufacturers gave a little bottle along with a cassette which had cloth tape in it and you put a few drops on the cloth tape and ran it through your machine. This also cleaned the pinch roller.

I think the thing to remember here is that you are not using IPA in contact with the pinch roller long term just enough to clean any crap off. If the pinch roller is shiny the IPA also removes the shiny surface to leave a surface which gives better friction.

Yes I can think of all sorts of problems if the Rubber roller was left drenched in the stuff for too long. It would probably swell up and eventually fall to bits but just as a cleaner once every so often its no problem.

Kev.
 
Posted by Bart Smith (Member # 780) on October 06, 2007, 04:29 PM:
 
IPA is indeed ideal as a tape path cleaner - great for heads, tape guides, and all other parts other than the pinch roller. The wet style tape cleaners that you are talking about were based around petroleum distillates, not IPA. Tape head cleaner that is sold tends to be IPA, but it is never described as being 'Pinch Roller Cleaner'.

The point is that IPA worsens the grip/friction of the roller. Saying that a little bit here and there is OK is a bit like saying that paint stripper is great for cleaning your fine china. Fair enough, a little bit won't seem to do any harm, but you are playing with fire.

My business has been repairing tape machines since the early 90's, I know what I'm talking about. Research the question on the internet - you'll find a vast body of evidence out there which will point you to the error of your ways.

The damage that IPA does to rubber is not immediately apparent - it take some time to manifest itself. One application is not likely to do significant harm, but repeated application will result in the outer surface developing a crazy-paved pattern of minute cracks, and the roller will no longer do the job it is meant to do.

Use the correct cleaners as I suggested above. But please don't use the excuse that you've never noticed any problems - it is not a good reason to recommend it.

Kevin, I'm not trying to attack you here: we all have different areas of expertise. I would hope that you would take note of what I have said, research the issue, and then come back with a better informed and considered answer.
 
Posted by Kevin Faulkner (Member # 6) on October 06, 2007, 07:37 PM:
 
Bart, I do take that as a personal attack! As for a "better informed and considered answer"?
I worked for Ilford's back in the 70's who were then the distributors of Elmo projectors. The rec for cleaning the film path including the pinch roller on sound machines was to use IPA. The rubber roller is infact made of a composite material and not just rubber as rubber is too soft for the job on it's own.

As I said earlier an application of IPA to clean the roller is NOT going to harm it but imersing it and leaving it may well do. Most users will never do this unless they are going to strip down their machines.

Please give me a little credit for my expertise going back 35 odd years.

Kev.
 
Posted by Joerg Niggemann (Member # 611) on October 07, 2007, 08:32 AM:
 
I think both of you are right in a way. Cleaning pinch rollers with IPA is very common and also recommended by some manufacturers. I know what I'm talking about because I worked in a service department for professional taperecorders. Of course, you will not (and should not) do that every time you clean your sound heads and film path. It's only necessary when you experience problems with wow/flutter which could be caused by a slippery pinch roller. Cleaning it once with IPA will last for years at "normal", non professional use.

Joerg
 
Posted by Tony Milman (Member # 7) on October 07, 2007, 11:58 AM:
 
I have found that a small amount of toothpaste applied to the roller has improved the take up. I tend to use the make that people with false teeth have as it seems to give better grip. Not sure what the brand is in the US but here it is poly-grip.

I found the cotton bud was not robust enough for the job and so use an old anti-plaque toothbrush that has an incredibly small head and soft bristles.

The trick is to be sparing in application and not to press too hard.
 
Posted by Rick Skowronek (Member # 385) on October 09, 2007, 01:37 PM:
 
I don't usually like to jump in in the middle of other folks posts but I thought I would just put in my two cents worth on the alcohol vs. other solvents on specifically the pinch rollers in both projectors and tape recorders (including VCRs). My experience includes several years owning a high audio repair business specializing in tape recorders all the way up to the studio types.

We always used denatured alcohol (IPA) on the pinch rollers. Other parts including the tape heads we used Freon TF, a totally non-reactive cleaner.

Now this is not just my opinion but many very heavy experts in the field with many years in the business. Here is one from a professional sound engineer and member of the Audio Engineering Society, Accoustical Society of America and chairman of the AES Standards Subcommittee: "I would be very cautious cleaning the rubber pinch roller with anything BUT alcohol. Most other solvents can damage the rubber by dissolving it and making it sticky. While it is true alcohol can dry rubber, it does so very slowly, and treatment once or twice a year with platen cleaner will restore the rubber surface."

I have to totally agree with Kev on this both personally from my experience and from other very knowledgeable field experts.

Rick
 
Posted by Tom Photiou (Member # 130) on October 09, 2007, 02:41 PM:
 
I myself,(at the advice of an projector engineer) now use "cleaning fluid" from RS componants with the code 180-847, its a lethal cleaner and i have never heard of it or used it before but have to say it is one S*** hot cleaner, it removes the sticky gunge off good metal and rubber without causing any problems to the rubber, it dries instantly and is (for me) a magic potion ive been looking for.A1
 
Posted by Joe Taffis (Member # 4) on October 09, 2007, 04:42 PM:
 
Tony.... [Big Grin] [Big Grin] [Big Grin] [Big Grin] you should write a complete manual! [Wink]
 
Posted by Rick Skowronek (Member # 385) on October 09, 2007, 05:12 PM:
 
Hi Tom,

I had a look at that solvent mix you recommended from RS Components. It is indeed a nice mixture of several fairly non-reactive solvents and should be extremely good for most of the applications we've been talking about here. Just a couple of caveats from what I've read about the contents, I wouldn't use this for tape heads themselves. It does sound like it will dissolve varnish which, of course, is the coating of the microfine wires inside a tape head. Other than that, it has a couple of solid but quickly evaporating solvents that will do a good job.

One last thing is that each solvent in this mix is extremely volatile and toxic. Wouldn't use it in a closed area and would avoid breathing any of the fumes if you can help it (it's a neurotoxin). Also, keep a fire extinguisher handy. It's classed as Extremely Flammable. Following good care, it should be as good as you say.

Rick
 
Posted by Bart Smith (Member # 780) on October 09, 2007, 05:47 PM:
 
I think that there are some important qualifications that need to be made regarding some of the responses above.

Rick Skowronek said:
quote:
We always used denatured alcohol (IPA) on the pinch rollers. Other parts including the tape heads we used Freon TF, a totally non-reactive cleaner.

Now this is not just my opinion but many very heavy experts in the field with many years in the business. Here is one from a professional sound engineer and member of the Audio Engineering Society, Accoustical Society of America and chairman of the AES Standards Subcommittee: "I would be very cautious cleaning the rubber pinch roller with anything BUT alcohol. Most other solvents can damage the rubber by dissolving it and making it sticky. While it is true alcohol can dry rubber, it does so very slowly, and treatment once or twice a year with platen cleaner will restore the rubber surface."

I have to totally agree with Kev on this both personally from my experience and from other very knowledgeable field experts.

Rick - the practice that you describe is substantively different from that which Kevin was recommending. Your quote from the guy at the AES makes it clear that his opinion is that cleaning pinch rollers with IPA is only OK in conjunction with regular and periodic application of platen cleaner to restore the surface. The result of only using IPA without subsequent application of platen cleaner - the pinch roller will slowly dry out and get worse and worse at performing its proper function, eventually becoming cracked, deformed, crumbly and useless. Once the damage to the rubber surface has become severe, it cannot be restored with platen cleaner/rubber restorer. You need a new pinch roller.
Rick, you say that you "totally agree with Kev on this". Taking into account what I have pointed out, do you still agree unreservedly? Would you really "give the pinch roller a good clean with Isoprop" as Kevin suggested without getting your platen cleaner out at some point later?

I have made the assumption that both Joerg Niggemann & Rick Skowronek are referring to the maintenance of professional open-reel recorders such as 24-track 2" machines. Please correct me if I am wrong. Maintenance and servicing schedules of equipment like those (worth potentially 5-figure sums) are somewhat different from those appropriate if you are dishing out advice to someone posting on an internet forum looking for guidance who has just bought a Super 8 projector on ebay.
In a professional environment the equipment will (hopefully!) be regularly serviced, by experienced technicians, in a predetermined and periodic pattern. In the specific case of the pro open-reel machines that I assume Joerg & Rick are referring to, the pinch roller is ultimately a consumable. It is typically the manufacturer's recommended practice to replace them after a few thousand hours of use, which is why they are normally easy to remove and replace without dismantling the machine. I recently bought a new (not NOS) pinch roller for a Tascam 1/2" 8-track machine that was manufactured in the late 80's. This is not something that one can do if you are looking for a replacement pinch roller for a Super 8 sound projector, as spares are not readily available. Your only choice is to maintain the pinch roller using the best practice that you can follow.

To simplify matters let's consider the following 3 practices (not an inclusive list, there are many others).

1) IPA then periodic treatment with Platen cleaner (as suggested by Rick).
2) Detergent solution cleaned off with water.
3) Cleaning with IPA (as suggested by Kevin).

If you are a dedicated user committed to organised and regular maintenance, practice 1) may well be the best.
If you are an amateur but serious enthusiast who wants to get the best out of your machine without too much fuss, practice 2) may well be the best.
BUT it is my opinion that practice 3) is the least advisable and most dangerous of the lot, as it is most likely to permanently damage the operation of your projector in the long run. It won't seem apparent immediately, but....

....most of the Super 8 projectors that we are concerned with in this discussion are 30 or so years old now. It would be nice to think that they could be up & running properly in another 30, 60, 90 years....???

At work I regularly come across pinch rollers from 20-50 year old equipment that have been ruined by treatment with chemicals such as IPA. They are frequently irrecoverably damaged. Don't let that happen to your cherished projector.

The only way to ensure this is by adopting the appropriate best practice that most suits your circumstances.

Kevin said when that he worked for Ilford in the 70's "The rec for cleaning the film path including the pinch roller on sound machines was to use IPA". I would take issue with that statement. The long-term stability and durability of rubber, rubber composites, other plastic and foam components back in those days (and before) were not as well understood or documented as they are now. Rubber becomes gooey or cracks and dries out, plastic become brittle and decays, and foam deteriorates and crumbles. What seemed to be good practice then should not be taken as an article of faith for good practice now.

This site is billed as being a discussion 'forum'. I'm not trying to attack any sacred cows here. I am however interested in establishing through discussion and debate what is best practice, and I'm convinced that there is more to be constructively said. In fifty years time people will read all of this and laugh about how shockingly naive and ill-informed all of our opinions are. But that will be the benefit of hindsight.

Bart
 
Posted by Rick Skowronek (Member # 385) on October 09, 2007, 06:17 PM:
 
Yikes!

Who woulda thought such a furor over a pinch roller? I'm politely backing away from this and advising forum members to look at all views and decide for themselves what they want for their little rubber friends. I believe all views are good and depend on the amount of use of their neat and somewhat ancient toys.

Whatever the case, all of it adds to the information for our membership.

Rick
 
Posted by Graham Ritchie (Member # 559) on October 10, 2007, 03:39 AM:
 
One interesting point that was mentioned, Quote "Rubber becomes gooey or cracks and dries out" I agree and its often an an "age thing" and there is nothing one can do about it, many projectors are at least 30yrs old, and when you think about it, the rollers are subjected to heat and wear over a long period, so after say, those 30yrs how can one prove that by using "Isoprop" on a cotton bud to clean rollers, and the stuff does evaporate quickly, is in any way causing problems, one also has to remember that in another 30yrs time, not only will the projectors be well and truly worn out but so will I [Wink] .

Graham. [Smile]
 
Posted by Lee Mannering (Member # 728) on October 10, 2007, 11:54 AM:
 
I still have a few of the Elmo Shutter rubbers left if it helps, but had marked them for Blackpool. Bit of a job to stick on but makes the machine run much better I think. I use superglue to stick them to the shutter and they hold well.

I'm stuck on Elmo. He.
[Eek!]
 
Posted by Tom Photiou (Member # 130) on October 10, 2007, 02:37 PM:
 
Lee, did you get these from a Mr moss?
I'd like to see if anyone has done a full review of this item,
Ive recently,(and thanks to a very well known projector repairer) done my own shutter replacement, the rubber had been removed but also and this is new for me, the shutter was very very finely machined on the shutters edge to give it a perfect flat edge instead of the very slightly rouned edge and i must say its brilliant and makes it run quiter.

Rick/ When i recieved the cleaner i read the the warnings that were sent with it, i think i need the bomb squad in when i use use it [Big Grin] it certainly is toxic but as you say, if used sensibly it should be fine and i must say, it dont half move the dirt and with so much ease. It took the sticky bits off my new rubber that i fitted to my machine with total 100% ease. i then used it to clean the edge of the new shutter and its all perfect again.

the jist is, a good cleaner, used sensibly should be more than good enuf for our hobby, i thank you [Big Grin] [Wink]
 
Posted by Lee Mannering (Member # 728) on October 11, 2007, 09:00 AM:
 
If memory serves me right I got these many moons ago from Essex Widescreen when they were trading and I only located as I have been having a sort out of cine gear finding all sorts of stuff around da house. Found a Elmo GS motor today...Its getting worse!

Who's Mr Moss anyhow?
 


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