CurtPalme.com Home Theater Forum

PaulB

Anyone tracked down a source for stainless steel 9500 LC chamber filler/bleed screws?

I can't get them in the UK as we only have metric sizes now. Hoping someone can source a few for me or point me in the right direction (need correct size and place that will export them to me). Tried Curt but I think I'm well under his radar at the moment.

Having cleaned out the LC chambers and put in new glycol, I'm really, really reluctant to put the old rusty screws back in and effectively start the problem over again! Happy to compensate for any costs incurred.
Thanks,
Paul

voodoo7869 · Joined: 19 Oct 2007 Posts: 193 Location: Chicago, IL USA

why don't you clean them with a wire brush and go to a local auto parts store and paint the tips with radiator paint for a car. it is glycol tolerant.

Or you could put a dab of silicone on the end of the screw and screw it in place just make sure the leave the tube with the bubble where the screws are for a couple of days. that will also stop the rust

**Curt Palme** · Posted: Tue Feb 19, 2008 3:14 pm Post subject:

Sorry, I meant to email, I've got nothing. One fine day I'll take one of the screws to the local but and bolt supply place, but that probably won't be for a couple of weeks.

aspec2 · Joined: 10 Apr 2006 Posts: 549

What size are they? I would be happy to find some.

Walt

draganm · Joined: 08 Mar 2006 Posts: 8990 Location: Colorado

i'm home today and will be out in the shop. Give me a few hours to figure it out and reply.

PaulB · Posted: Tue Feb 19, 2008 5:57 pm Post subject:

Good ideas Voodoo but I'd much prefer the simplicity of a better quality screw (!? Shocked

). I had a look for the paint but couldn't find any on my initial searches and I'm not keen on the silicone option as I don't want to risk having to fish out blobs of silicone the next time I unscrew the filler screws (hopefully I won't have to unscrew them again, but....!)

Walt, Draganm I very much appreciate the offer of assistance.
Paul

draganm · Joined: 08 Mar 2006 Posts: 8990 Location: Colorado

ok, i got it. It's a simple #6-32 pan head screw, 3/8" lenght. In 316 ultra corrosion resistant stainless steel they cost a whopping $12. for a bag of 100.

part number 91735A146 at http://www.mcmaster.com/ The only difference here is that these are Phillips screwdriver style instad of hex-head drive.
I would also replace the "sealing washer" under screw at the same time. these are actually more epxensive, $9.21 for a pack of 10. partr number 93783A007

PaulB · Posted: Wed Feb 20, 2008 9:34 am Post subject:

Superb!!

Many, many thanks Draganm, thats absolutely brilliant! I've just tried to order from them direct as they do ship to the UK so lets see how that pans out, hopefully that will be sucessful.

My thaks also to Walt, may yet still need you my friend!

Again, I'd recommend this to anyone who has an LC marquee as its clearly the iron screws that are causing major contamination to the chambers.
Paul

PaulB · Posted: Wed Feb 20, 2008 3:12 pm Post subject:

Just had a reply from the suppliers, because I am overseas they are not willing to send me the screws and washers - bummer but seems to be the norm these days Sad

Ok Walt, you still willing to grab some of these for me?

Thanks,
Paul

aspec2 · Joined: 10 Apr 2006 Posts: 549

Yes....I'm going out today to find what you want. These screws should be available at any good hardware. PM an address.

Walt

aspec2 · Joined: 10 Apr 2006 Posts: 549

**AnalogRocks** · Posted: Wed Feb 20, 2008 4:52 pm Post subject:

PaulB · Posted: Wed Feb 20, 2008 4:57 pm Post subject:

PaulB · Posted: Fri Mar 14, 2008 8:29 am Post subject:

A public "thank you" to Walt (aspec2) for helping me out with the screws. Very generous Walt and much appreciated.

Best Regards,
Paul

armstrr · Joined: 26 Mar 2006 Posts: 160

how does this look

http://www.amazon.com/Stainless-Steel-Phillips-Machine-Length/dp/B000MN4PSS/ref=sr_1_2?ie=UTF8&s=industrial&qid=1212176397&sr=8-2

PaulB · Posted: Fri May 30, 2008 9:13 pm Post subject:

armstrr · Joined: 26 Mar 2006 Posts: 160

hey paul. thanks.

can you share any info on changing the bellows? i'm fairly handy, and the guy who is helping me rips and rebuilds race cars in his sleep...so i think between the two of us we should be able to handle it. any hints you could offer would be appreciated.

ps, is this the paul who bought an 8500lc from a canadian fella in sarnia, ontario a couple years ago? (if so, i know that seller REAL well...i thinks he's a stand up guy if you don't mind him er, um, me saying!)

PaulB · Posted: Sat May 31, 2008 5:51 am Post subject:

Different Paul I'm afraid, good name though!

I've been through the Bellows process. Never done it before but found it quite easy.

Do a search on Bellows and read up all the process. There are some great tips scattered about. My own experience is detailed here https://www.curtpalme.com/forum_archived/viewtopic.php@t=7361.html with some great input from other forum members. This will also help http://www.curtpalme.com/Changing_C_Elements1.shtm

I would think that the two of you will find it pretty straight-forward. To be honest, once you open up the Marquee and see how it all fits together theres nothing really mechanically difficult about it construction-wise. Just do your research and preparation and there will be no surprises! Thumbs Up

draganm · Joined: 08 Mar 2006 Posts: 8990 Location: Colorado

I just helped a friend re-bellow an 8500Lc. It was in fact quite easy. The one thing we didn't bother with was all that syringe glycol extraction. There's really no reason for it either. Also, in the C element tech-tip article on this web-site it talks about prying the C-elements out from the mounting plate. That just ain't gonna happen in most cases. The C-elelment is siliconed to the bellows, so a lot of prying must just crack the $150. c-element. What we did was this.This process is better with 2 people but it's reall fast

1) remove tube from chassis, you can leave the plastic covers and yokes on.
2) carry tube assembly over to kitchen sink
3) remove the upper and lower pivot plates that hold the 2 halves of the Lc chamber apart.
3) hold face of tube and c-element over the sink, rest back of tube on counter
4) use a razor knife with a very small extension of the blade, like 1/8th inch, and working from the bottom cut into the bellows and slice up
5) wait for Glycol to drain, this takes only a few seconds
6) the old bellows will now easilly tear and you can pull the entire front plate off with C-element and half a bellow attached.
7) pull the c-element out throug the front of plate, then carefully peel off the old bellow half. Gently wash c-element wiht mild sap and set in safe place
8)remove the steel ring holding the back-half of bellow to rear mounting plate, throw away old rusty screws
9) peel off old bellow half and discard
10) clean back half of old maounting plate, you don't want any old RTV there because new RTV will not stick to old cured RTV. You want a clean metal surface although the metal can be stained Black from the old RTV, just no build-up
10.5) wash LC chamber and face of tube with dish-soap and hot water, rinse well with sink sprayer and allow to dry thoroughly.
11) Apply an even layer of new Black RTV to back mounting plate, install new bellows and support ring. Install 28 new stainless steel screws and start tightening down EVENLY in a criss-cross pattern. Do not crank these down, they should all be snug so tha tthe rubber is compressed evenly but not crushed or extruded out the side. Some RTV will squeeze out and that's normal
12) allow 24 hours to cure.
13) feed front of bellows lip through the front half of the LC chamber, re-install the upper/lower pivot plates
14) apply a very thin coat of Black RTV to front of bellows lip, install C-element with rounded (convex) face pointing IN towards tube and concave face out. Install retaining ring, tighten down securely.
15) allow to cure another 24 hours minimum, 48 is better
16)fill chamber will glycol but not all the way, leave an air-gap on top
17) squeeze a little RTV into fill holes and then install the screws. Allow to cure another 24 hours.
The very last step is important because the threaded fill holes are not anodized, that's where all the corrosion comes from. hopefully the RTV you added will keep that bare metal surface away from the Glycol.

armstrr · Joined: 26 Mar 2006 Posts: 160

thanks Paul!
thanks Dragan!

the 28 screws you reference: are they the same as the fill screws: 6-32? how long? if not these...what? thanks again.