8mm Forum: Elf RT1 Take Up Problem

This is topic Elf RT1 Take Up Problem in forum 16mm Forum at 8mm Forum.

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Posted by Simon McConway (Member # 219) on June 28, 2009, 05:28 PM:

Can anyone advise on a weak take up on an RT1. The adjuster on the rear arm doesn't seem to do any good and eventually the take up spool stops turning. The belt inside the arm is fine and grease free, the cork liner on the take up arm is fine. Any advice?

Posted by Fabrizio Mosca (Member # 142) on June 29, 2009, 01:42 AM:

I have a similar problem with my NT1, and it's due to a loosen screw on the clutch cover that doesn't lock on the drive gear.

Have a look at the Eiki N service manual (download here http://super8.no/?cat=4 ). RT1 take up mechanism is the same of N series.

Posted by John Whittle (Member # 22) on June 29, 2009, 08:44 AM:

Simon,

When you say the cork liner is fine, what condition is it?

You should be able to put a single layer of film inside the drum and it should make a tight fit onto the steel pulley drive. The cork liner should not be dry, Eiki recommended a light coating of phonolub, a GC product that used to be used on record changers (remember those?). Its a very light grease and is still available.

You can run with the cover off the arm and make sure that the belt is turning and the drive pulley is turning. The drum is held on with a 3mm screw and a hardened washer which allows the drum a slight movement such that as the reel increases in weight, it allows it to put more force on the drive pulley for additional torque. Make sure the washer is there and that the drum without a reel has a slight up and down play to it.

Also I've found that the take-up works best with 1600 foot metal reels. Lighter plastic reels can be problematic.

John

Posted by Kevin Faulkner (Member # 6) on June 29, 2009, 08:45 AM:

Whenever I have seen this problem its been down to the cork liner in the take-up reel arm in need of replacement.

Yes I bet the cork does look ok but what seems to happen is that the cork goes hard and polishes up and also gets a bit thinner with age.

I think if you replace this cork you will find the take-up will be much better.

Kev.

Posted by Michael O'Regan (Member # 938) on June 29, 2009, 10:20 AM:

This seems to be a recurrent problem with the R and the N series Eikis. I have got to the stage where only 2000ft reels take-up correctly on my RM-1 and also my RT-1. 1600ft, whether metal or plastic, results in very slack take-up, and occasionally just stops completely. I assume its some kinda weight thing.
I've adjusted, greased and replaced the cork lining at different times without a lot of success.
I've never (yet!!!) had a problem when using the larger reels.

-Mike

[ June 29, 2009, 01:13 PM: Message edited by: Michael O'Regan ]

Posted by Simon McConway (Member # 219) on June 29, 2009, 10:23 AM:

I have just realised that the hardened washer is missing. Think I've found another one, so will fit that and give it a go. Many thanks for the advice.

Posted by Simon McConway (Member # 219) on July 02, 2009, 12:43 PM:

Still struggling with this weak take up spool! Basically tried new belts (many different sizes!) cleaning up the pulleys etc etc. The arm on this machine has the adjuster on the back to adjust the tension; nothing makes a difference...it always slows down and stops after a while. Has anyone got any more ideas? Anyone got a new cork lined pulley, that has the spool attached to it's shaft eventually.

Posted by John Whittle (Member # 22) on July 02, 2009, 01:08 PM:

The type of belt is critical for the MS/ST/RT/NT machines. You must use the polyurtheane belt that Eiki used. Rubber belts just don't work and the belt cannot bottom in the pulley.

I never liked this take-up and finally just changed the take-up arm for one of an SL machine with the flat belt which works much better (that's the design that they used on the final machines. The arm fits and you just have to drill a hole for the latch to locate the arm in the up position. Changing the feed arm is a bit more complicated, but can be done as well. If you make the change, all the internal parts stay the same and you just change the pulley and arm and you'll have much better results. Look for a early SL parts machine since those are usually the cheapest.

You can reline the cork inside the drum, you can find suitable material at an auto parts store and then cut and glue the new material after you've removed the old stuff (a hand dremel tool will help with that part).

John

Posted by Kevin Faulkner (Member # 6) on July 02, 2009, 04:44 PM:

Simon, Email me at super8 at mrelmo dot co dot uk. I bought some cork to do an RM and my current NT1. I have two thicknesses 1mm and 1.5mm. I had to buy 1M squares of the stuff so can send you a small piece of each to try.

Kev.

Posted by Hugh McCullough (Member # 696) on July 02, 2009, 05:19 PM:

The original Elf belts have a circumference of approx 470mm.
It is not easy to obtain 470mm belts nowadays so most people supply replacement belts that have a circumference of 500mm. 30mm too large.
This is just a tad too large for some, but not all, ELF machines, and when the belt starts to stretch, or is under pressure, it tends to bind between the pulley and the inner side of the arm.
The answer to this problem, if indeed it is belt trouble, is to use a Pathescope 200B motor drive belt.
This has a circumference of 455mm only 15mm smaller than the original

Posted by Michael O'Regan (Member # 938) on July 03, 2009, 01:21 PM:

Where can one obtain the correct polyurethane belts in the UK?

Posted by Hugh McCullough (Member # 696) on July 03, 2009, 03:58 PM:

Michael.

I do not know of anyone who can supply polyurethane belts, but Nitrail belts are a very good substitute.
I can supply these with a 25% discount to any Forum member.
www.cinebelts.co.uk

Posted by Michael O'Regan (Member # 938) on July 03, 2009, 05:05 PM:

But.....our friend above says it has to be polyurethane.....!!!!!

[Smile]

Posted by Hugh McCullough (Member # 696) on July 04, 2009, 04:04 AM:

Good for him, but I am not getting into an silly argument over the types of belts to use.
If you wish to use polyurethane, then use it.

Posted by Martin Jones (Member # 1163) on July 04, 2009, 04:22 AM:

Perhaps I'm sticking my neck out, but the belting I have to offer (see "Weldable Belting" under "Equipment For sale" sections) is described as "polyurethane" by the manufacturer. I don't know if it is suitable for the Eikis.... but it's not exactly expensive, so perhaps it's worth a try. It's fine for all the other purposes I've put it to and it's easy and economical to use.

Martin

Posted by Hugh McCullough (Member # 696) on July 04, 2009, 04:33 AM:

Hello Martin.

I was wondering what material your weldable belting was made from.
If it works for other projectors, I see no reason why it should not work for Eikis.

Posted by Martin Jones (Member # 1163) on July 04, 2009, 04:41 AM:

Hugh, as in the previous post... the manufacturer says it's polyurethane. It's green in colour, fairly stiff (i.e not very stretchy) and has a rough textured service with great grip. Best cut to length by fitting to the job, and then welded by melting the ends and pressing together. If it's not tight enough, cut out the weld and re-do!
Martin

Posted by Jose Artiles (Member # 471) on July 04, 2009, 07:04 AM:

I was having the same exact trouble until i changed the belts for the original eiki belts.Only one and gentle guy sell it at the moment (that i know at least) and is....RC´S CLASSIC COLLECTIONS they are eiki and bell and howell´s offical dealers and only sells fresh and original stuff for our loving projectors....it cost me about 6 month to find the original eiki belts until i know them,believe me.... i put the original eiki belts on my rt-1 and the trouble dissapear.Welding belts like our fellow member says can be a good solution too,the green material is a special material used today as a perfect polyurethane substitute and is called polycord but you need that the belt has a 6mm wide.The part number for the take belt is ST13151,you can send rc´s classic collections a mail to this address:
patchetts (@) ameritech (dot) net
Mr richard Patchetts is a wonderful person,very kind and helpfull with all collectors around the world,send him a mail and you not be desapointed.
good luck!!!
Jose [Smile]

Posted by Martin Jones (Member # 1163) on July 04, 2009, 07:38 AM:

Thank you, Jose. I have both 3 mm and 5 mm diameter belting available.
Martin

Posted by John Whittle (Member # 22) on July 04, 2009, 09:55 AM:

Just to clear up the material of the belt.

The original Eiki Belts were Polyurtheane and the take-up was designed to use the properties of these belts. They used this as far back as the MS-850 machine and stopped with the SL redesigned take-up.

While the original material seems indestructible, the belts would turn to goo and or crumble after many years. This was a fault of the polyurtheane materials made in the 60s, 70s.

The Polycord material should work just fine as long as the diameter is 6mm and the length is cut properly and the weld is properly made and smooth.

This is the reason I changed the arms out on my own machines for the later design of the SL to solve this problem.

John

Posted by Richard C Patchett (Member # 974) on July 05, 2009, 10:33 AM:

Greetings
I have been using these belts ST13151 for a number of years And have worked on many and have not seen any bad ones that i have sold or worked (replaced) on in the past 10 years + Back then they must have use a different polyurethane material Its 2009 now! Just like the new plastic worm gear. Whens that going to crack?
After how many years?

quote:

While the original material seems indestructible, the belts would turn to goo and or crumble after many years. This was a fault of the polyurethane materials made in the 60s, 70s.

Posted by Michael O'Regan (Member # 938) on July 05, 2009, 01:21 PM:

QUOTE: "Good for him, but I am not getting into an silly argument over the types of belts to use.
If you wish to use polyurethane, then use it."

Well, I certainly didn't mean any offense to you or your belts, Hugh. I'm not sure why you took it like that.

Posted by Hugh McCullough (Member # 696) on July 05, 2009, 05:11 PM:

Sorry Michael.

I did not mean to offend anyone, but I do have a weird sense of humour, and tend to look at things from a slightly different angle.
What I really meant, and should have said was "Whatever works for you then use it. Nothing is set in stone, unless it's a sword"

More to the point, are we helping Simon with his take up trouble?

Has he contacted Kevin about his kind offer of cork lining?

It would be nice to hear if his trouble has been resolved.

Posted by Simon McConway (Member # 219) on July 07, 2009, 06:41 AM:

Just awaiting the cork lining from Kevin. Then I will report back. Many, many thanks for your help guys.

Posted by Kevin Faulkner (Member # 6) on July 07, 2009, 07:41 AM:

Simon, Seeing this has just reminded me to get it in the post for you. I'll do that asap.

Kev.

Posted by frank arnstein (Member # 330) on July 11, 2009, 03:31 AM:

Hi Posters on the thread...
With regards to this annoying problem of weak take up function.
I have found that certain small fibre washers that are usually on the clutch spindle are quite important. If you leave them out then it effects the amount of friction available to the cork linings. The spindle has to be quite loose to the touch when wobbled. This ensures that when the weight of a reel is hanging on the spindle, it will allow the the cork to press hard against the drum. If the drum cant hang down enough it will start to slip even with a reel hanging off it. Refitting the fibre washers to adjust the right spacing, will restore the loose hanging nature of the spindle & should drive much better.
Good luck with it
dogtor puffefish

Posted by John Whittle (Member # 22) on July 11, 2009, 04:37 PM:

Good point, you need to check all of the parts to make sure they're present and also for wear. The drum requires wobble so that as the weight of film increases on the reel it applies more pressure to the drum.

So look at the drum, there is usually a fibre washer then it slips onto the drum and then there is a hardened washer and a 3mm screw. Also the bushing that the pulley roates on has a hole that should allow for vertical wobble of the drum.

Finally the cork lining wears and may need to be resurfaced (we used to order spare parts!) and then treated with phonolube so allow slippage otherwise too much drag is fed back to the motor trying to turn the reel and it will overheat.

Finally, the design works best when you use a 1600 foot Goldberg reel. It has the right weight to make the system work. The only caution is on start-up you have to watch and make sure that the reel is held back a bit so that it doesn't turn too fast and snap your leader.

John

Posted by Simon McConway (Member # 219) on July 14, 2009, 03:14 PM:

At last! With many thanks to Kevin for kindly sending me new cork sheets, the problem appears sorted! I stripped out the old cork, whick seemed to have shrunk and worn on reflection. Then, I cut and super-glued in a new piece of cork; this seemed much rougher and springy than the old cork. Then, success! A whole 1600' was taken-up by the projector perfectly! I haven't put any grease on yet...I'm scared I'll undo the good effect I now have! How much should be applied? Normally, I use spray-grease.

Posted by Kevin Faulkner (Member # 6) on July 14, 2009, 06:38 PM:

I just use a real thin application of silicon grease. I just put a very thin coating on the tip of my finger and then rub it onto the surface of the cork. This is where a lot of people go over the top and apply loads of the stuff and then wonder why the take-up stops working!
The main reason for the grease (I think) is to stop too much drag on the motor etc. I think it also helps stop the cork from polishing up too quickly.

I'm glad it sorted your problems Simon and am glad to have been able to help.

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