8mm Forum: Replace missing spring belt with urethane belt?

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Posted by Tom Spielman (Member # 5352) on April 16, 2016, 12:48 AM:

I picked up a new projector this week but would like to fix up my old one to sell on craigslist. Not thinking I'm going to make a fortune, I just like to sell stuff that works. The bulb is good.

The projector is a Sekonic Model 30C. I can find the rubber belts on eBay but the belt on the take up arm was a spring belt I'm pretty sure and I can't find a replacement for that. I was going to try buying one for a Bell and Howell to see if it would fit or if I could shorten it if needed. However, spending $40 on belts doesn't seem like a great idea for a projector I'm not going to keep.

I know I could make a urethane belt, but I'm not sure if that would work acceptably or not. And as long I was going to make a belt for that, I might as well save some money and make the rest of the belts too. If I do a decent job welding the ends, will they hold up? I don't want to sell something that falls apart a week later.

Any thoughts?

Posted by Pasquale DAlessio (Member # 2052) on April 16, 2016, 01:08 AM:

HI Tom

I have a spring belt I am not using. Measure the length with a string and let me know. If mine is the right size I will send it to you.

PatD

[ April 16, 2016, 06:13 AM: Message edited by: Pasquale DAlessio ]

Posted by Tom Spielman (Member # 5352) on April 16, 2016, 08:15 AM:

Thank you, that's very generous !

I won't have a chance to measure it until tonight, but I will let you know.

Posted by Barry Fritz (Member # 1865) on April 16, 2016, 10:56 AM:

If you are talking about making a belt from the material Larry Urbanski sells, it will hold up very well. I am not certain about using it in place of the spring belt as I have never tried that. It would probably work OK.

Posted by Pasquale DAlessio (Member # 2052) on April 16, 2016, 11:06 AM:

Tom

The one I have measure 27.50 inches not stretched at all. If it's too long and you are handy you can actually cut it and rejoin it by bending 2 hooks one on each end. But they have to be perfect.

Posted by Tom Spielman (Member # 5352) on April 16, 2016, 07:27 PM:

I measured the path with a string and it's about 11.5 inches. The spring belt for the supply arm is 10.5 inches long and that path is also 11.5. The spring seems to work just fine on the take up arm too so I'm guessing that's the right length (10.5).

Anyway, 27.5 is plenty long. There's more than enough extra there to practice making a hook with, - I'd leave the eye on the other end intact.

Are you sure you won't need it? Given, how long it is, I'm wondering if it might be wider too. Mine is only 3mm thick.

Posted by Pasquale DAlessio (Member # 2052) on April 17, 2016, 02:50 AM:

This one is the same thickness. Send me your address and I will mail it to you.

Posted by Steve Klare (Member # 12) on April 17, 2016, 06:44 AM:

I wondered if there was anybody out there that still makes spring belts: after all I haven't ever seen them used anywhere else than a movie projector, so I Googled it.

I got loads of hits, but most of 'em also sell spring jewelry and spring shoes and other spring fashion accessories! (Be careful what you Google for!)

I wear the same kind of belt all year so these weren't much help...

I did find one possibility:

Durabelt

They sell through distributors, you would need to contact them and ask for the name of one.

Tom, I hope Pat's generous offer works out for you, but if nothing else this could be plan "B".

McMaster-Carr has spring belts, but the minimum diameter is 3/16": you probably need 1/8".

Posted by Joe Taffis (Member # 4) on April 17, 2016, 07:27 AM:

Barry, I tried the belt material from Urbanski to replace a spring belt. It worked, but didn't last too long...
Tom, I already got a replacement metal spring belt for a Chinon 7500 from Mark at "isellprojectorbelts". I just had to give him the length. You can contact Mark privately instead of going through eBay. PM me for his e-mail address...

Posted by Steve Klare (Member # 12) on April 17, 2016, 08:54 AM:

Mark's who I'd go to!

Thanks Joe, I had no idea he did spring belts!

-now if I could only find a nice pair of shoes to go with it!

Posted by Barry Fritz (Member # 1865) on April 17, 2016, 09:20 PM:

I have dealt with Mark directly also. You do need to provide exact measurements for the belt you need. He can get most any size/type.

Posted by Tom Spielman (Member # 5352) on April 27, 2016, 12:32 PM:

Just wanted to follow-up since this forum was very helpful and maybe this will help somebody else.

Pat sent me a spring belt he had that was quite a bit longer and slightly thicker than the original from my projector. I'll create another post describing how I shortened it but basically I used a dremel with cutting wheel to get a clean cut. Then I used a butter knife and a small needle nose pliers to bend up the last loop and turn it toward the center to form the hook.

It worked really well even though it was a slightly thicker diameter. The takeaway is that you don't need to find a spring belt of the exact same length. With a few tools you can get the size you need from a longer one.

My original plan was to get the 3 rubber belts from Ebay, but I found one of them at a local hardware store for $0.99. For the other two a pack of 10 from Amazon for $1.49 took care of it. That was really lucky. The next smaller and larger sizes would have been more like $10. Thanks to those that suggested looking for appropriate sized O-rings.

So for a pretty small investment I'll have a working projector that I can sell on Craigslist which will cover the cost of my new projector and help someone else get into this hobby for not much money.

Posted by Barry Fritz (Member # 1865) on April 27, 2016, 05:07 PM:

Way to go. Ace Hardware has saved me a lot of time and money on rubber belts.

Posted by Pasquale DAlessio (Member # 2052) on April 27, 2016, 05:24 PM:

Glad it worked for you Tom! Happy to be of help to you.

PatD0

Barry, Ditto on the Ace Hardware!

Posted by Laurie Harrison (Member # 6482) on June 03, 2018, 09:46 PM:

Hi Tom:

I am also trying to rehabilitate a Sekonic 8. My problem is the main rubber belt that drives the main gears for forward advance of the film and also the fan is stretched out. You folks seem to know a lot about fixing these. Do you have any advice on what size of belt?Where to get one? Also do I need to disassemble the fan unit to replace? Looks complicated.

Thanks for any advice. I am Laurie at laurie.harrison@gmail.com. In Toronto.

Posted by Janice Glesser (Member # 2758) on June 03, 2018, 10:19 PM:

Welcome Laurie... Contact a seller on Ebay called "isellprojectorbelts." I have bought from him and he is very helpful. If he doesn't have the size for your specific projector, he will ask you to take a piece of string and wrap it around the pulleys and give him the measurement. He can find a belt to fit.

Posted by Nantawat Kittiwarakul (Member # 6050) on June 03, 2018, 11:29 PM:

If my understanding is correct this projector is,much like 90% of regular/super8 projectors in this world - that you can replace its belt with usual o-ring found in hardware stores.

Actually ALL of my super8 projector's belts were replaced with o-rings,without any negative effect at all. Might need to re calibrate the speed somewhat,but that's it. [Wink]

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