Page 2 of 3 FirstFirst 123 LastLast
Results 16 to 30 of 44

Thread: Resurround Step-by-step

  1. #16
    Senior Seņor boputnam's Avatar
    Join Date
    Apr 2003
    Location
    northern california
    Posts
    7,007

    Step 13

    The two completed baskets, hooked-up and running the 30Hz test tone for the entire drying cycle. This is what the drying phase looks like. It's a bit boring, but oh-so-important. Keep that 30Hz tone playing constantly - it ensures the voice-coil is centered, and allows you to hear if things need adjusting. Check on them periodically, but go find something else to do

    and let them dry...

    Attached Images Attached Images  
    Last edited by boputnam; 07-14-2003 at 07:57 PM.
    bo

    "Indeed, not!!"

  2. #17
    Senior Seņor boputnam's Avatar
    Join Date
    Apr 2003
    Location
    northern california
    Posts
    7,007

    2245H - an addendum...

    In resurrounding a pair of 2245H's today, it occurred that I had omitted a handy way of appyling the glue bead to the cone, in tight-fitting instances. These instances are when you cannot have the surround in-place while laying the glue bead.

    When you simply cannot get glue to the cone edge any other way, a means is to hold the frame on-edge, while slowly rolling the cone, trace a thin bead around behind the cone, with the tip of the glue container as close to the edge as possible. Good lighting is necessary, and avoid excess glue which could drip (but that is not fatal...).

    Once the bead is applied and a minute-or-so has passed, slip the surround into position, working around into behind the cone edge. With the glue bead at/near the cone-edge, the glue is smeared nicely across the surround mounting surface, giving it a good grab.

    Done.
    bo

    "Indeed, not!!"

  3. #18
    Senior Member DavidF's Avatar
    Join Date
    Apr 2003
    Location
    San Jose CA
    Posts
    910
    Thanks for the effort to include all the photos, Bo. Interesting to "watch". I have not reconed or even renewed surrounds but a thought I had prior to trying this is to put the driver on a turntable that may assist in getting around the driver. Using the test tone to align the driver during the process would work against this idea. Have you ever tried using a turntable and would this help in any steps of the process?

    Thanks, David F

  4. #19
    Senior Seņor boputnam's Avatar
    Join Date
    Apr 2003
    Location
    northern california
    Posts
    7,007
    Hey, DavidF...

    No sweat - I queried Giskard prior to posting all this and he agreed this might be a worthwhile effort. It's not hard, just unusual work. I wish I'd had a photo-path before my first - resurround, that is!

    The turntable is a good idea, but you want to rotate it manually, and back and forth. I included a comment about a LazySusan in, I think, the first post of this Thread. The FOH pro engineer in New Mexico who looks after my (nearly 3-decade ) band, used to tour with a number of bands in the 70's/80's, and they did this work on the road, on the fly. They used a LazySusan, which is a great idea. And, it would really only come-in handy during the cleaning round-and-round.

    During the 30Hz drying/positioning phase, you will want things VERY unmoving (and quiet!!). And, be real patient, and relaxed here - let the glue get tacky before you really try and get the surround and frame to stick. And, only press down gently, and straight down. If you try anything quick or "efficient" you will invariably move the surround very slightly, and might get things off-axis.
    bo

    "Indeed, not!!"

  5. #20
    Senior Member Guido's Avatar
    Join Date
    Apr 2003
    Location
    Germany
    Posts
    2,506

    THANKS!!!

    Thank you very much for this Bo!
    I was looking for such a detailed description a long time.

    If you ever do a reconing, would you do pictures and description as well?

    This would be great

  6. #21
    Senior Seņor boputnam's Avatar
    Join Date
    Apr 2003
    Location
    northern california
    Posts
    7,007

    Recone Tome

    "If you ever do a reconing, would you do pictures and description as well?"
    Ugh! I considered doing that while reconing a 116H last weekend, but felt I was deluding myself in thinking anyone cared on all this

    There isn't a great deal more to it - the cleaning is the biggest hassle. That damn Bostex crap is inconsistent to remove, depending upon age and what it's glued to. Only additional steps to a resurround are:

    Carefully cut the spider off the basket - use sharp Xacto knife (#10 blade my choice). Remember, the voice coil is in the gap, so don't act impetuously...

    Cut the surround away, as per this Thread. But a bit more carefully since the spider is not there to stabilize the voice coil in the gap.

    Lift out cone/spider. Use this to create or add to the interesting shrine you have of completely useless parts that are somehow too invaluable to simply discard...

    Immediately cover gap and pole-piece completely with masking tape. Begin the dreaded cleaning. Take your time. Clean away all dust and debris completely. Then, take a thin piece of cardboard and run it around inside the gap making sure there is nothing there. A trick learnt from an old reconer (thanks, Giskard! ) is, if you can, reverse a piece of masking tape on this to gather anything from the gap.

    I prefer the recone kits that are pre-assembled cone and spider - they're easier to get everything aligned, and less to do! Carefully slip the assembly into position - check for fit, and alignment of mounting holes through surround (if relevant).

    With the assembly in position, thread the voice coil leads throught the terminal connectors. Leave the leads as long as needed - not too long, not too short. A slight "sag" in the leads seems about right. Solder. Trim excess. It is critical to get these leads soldered before proceeding, to allow you to run the 30Hz test tone through the transducer for centering while gluing.

    Carefully, lift-out the cone assembly as much as possible. Keep it vertical. In some instances, you may be able to carefully lay it over the edge of the basket - the length of the soldered leads, and the terminal position on the frame, are your limitations. The benefits to carefully doing this, is you can get the gooey Bostex on more evenly where you want it, and not all over everything else. But be VERY mindful the voice coil is exposed and vulnerable. Just be careful, dang it!

    Spread a good coat of Bostex on the basket - it's typically old, and poorly behaved, so get it on good and even. Slip the cone assembly vertically and very carefully back into position, and gently press the spider down into position into the Bostex. Start the 30Hz test tone. Listen for any "rubbing", "scraping", of "fuzzing" sound, and see if very slight budges to the spider relieve this. NOTHING DRASTIC, just gentle budges into position - but you need to sort-of push/pull from opposite sides of the spider at the same time. You should hear nothing mechanical from the cone - only the soft free-air resonance of the 30Hz tone.

    Keep the warming lights on, and the 30Hz test tone going the entire time until dry. Do not leave the building, or come back to this Forum to see what is going on out here. Stay with it, and it will last another 20-years...

    I need to do another 116H, but await a much-needed kit. If there's any pictures worth posting, I'll do so.

    Good luck!
    Last edited by boputnam; 07-31-2003 at 07:16 AM.
    bo

    "Indeed, not!!"

  7. #22
    Senior Member Don C's Avatar
    Join Date
    Apr 2003
    Location
    Santa Rosa CA
    Posts
    1,658
    I am surprised that you don't mention shimming the voice coil to keep it straight. Didn't JBL originaly line things up by putting a shim tube inside the voice coil, and then removing that when the glue has dried? I would thing that it would be possible to duplicate that by finding some flat materiel that fits the gap and rolling it into a tube.

  8. #23
    Senior Seņor boputnam's Avatar
    Join Date
    Apr 2003
    Location
    northern california
    Posts
    7,007
    "I am surprised that you don't mention shimming the voice coil to keep it straight."
    A "shim" tube is included in the recone kit - it is thin, clear plastic, and helps maintain and protect the coil form. I don't think I could "roll one" that precise!

    I removed the tube as I slipped the voice coil into the gap. The fit was too snug to cram it in with the voice coil. I did try and did not want to force it into the gap: I actually had some difficulty getting it back out. I can only speak to this case, and the tube could not be fit into the gap without risking damage to the coil. Other kits/fits may vary, but with this one (C8R116A) that's how it went.

    The 30Hz tone ensured me things were aligned - only the most minor adjustment was needed. The results were excellent. Sweeps afterward are noiseless, and the performance seems perfect.

    Thanks for the tip!
    Last edited by boputnam; 07-31-2003 at 09:24 AM.
    bo

    "Indeed, not!!"

  9. #24
    Senior Member LE15-Thumper's Avatar
    Join Date
    Feb 2004
    Location
    Winnipeg, Canada
    Posts
    603
    What exactly do you mean by "minor adjustments" during the 30 hz test tone period ? Are you talking about actually shifting the cone over in a certain direction so it doesn't rub ? If so, how do you do this while the glue is hardening ?

    TIA
    LE15-Thumper
    "Give me JBL, or give me death"

  10. #25
    Senior Member GordonW's Avatar
    Join Date
    May 2003
    Location
    Marietta/Moultrie GA USA
    Posts
    1,457
    Wow, I always use a shim when reconing. I've been burned too many times, reconing drivers, to EVER not use one. Unlike a refoam, there's TWO dimensions to get right- 1) side-to-side offset of the voice coil and 2) "cocking" or angling the voice coil in the gap, where it may hit near the ends of travel even though it's "clear" in the middle of the range. Not something I care to try to eyeball, especially when gluing a spider to a basket!

    In my work, if a provided shim doesn't work, I get or make another one. One thing that makes a great "emergency" shim- take those shiny, hard-paper junk mail advertising sheets that come in the mail (pizza ads, etc), and cut them into long strips. Then, take the strips, and wrap them into cylindrical layers to form a multi-layer shim "tube", until you get enough layers to fill up the gap to where the voice coil fits snugly (but not so snugly you can't get the shim back out easily) in the gap. Works great!! Also, the clear plastic from report covers works great the same way- and is preferable, if available, since it won't tear if you get it in there too tight, not as easily as paper. But, the shiny paper works fine, if you use common sense...

    Oh, another tip: if you make sure that one side of your shim stock has a PERFECTLY STRAIGHT edge, and you bottom the shim out against the pole piece (shove it ALL the way in as far as it can go, until the shim bottoms out), it will keep the shim PERFECTLY SQUARE in angle with respect to the pole piece. Great way to avoid problems with case (2) misalignment, as mentioned in the first paragraph...

    Regards,
    Gordon.

  11. #26
    Senior Seņor boputnam's Avatar
    Join Date
    Apr 2003
    Location
    northern california
    Posts
    7,007
    Originally posted by GordonW
    Wow, I always use a shim when reconing.
    Yup. Gordon's right as always.

    TIA - I've had some that just wouldn't align, no matter what. And, you can try this if you get recones off eBay that rub. Working on sound advice, using MEK I've softened the glue on the surround and then the spider, carefully loosening one, then the other. Then clean the basket and reglue and then man-handle ( ever so gently...) first the spider, and then the surround/cone into alignment as the glue is drying.
    Last edited by boputnam; 08-24-2004 at 07:45 AM.
    bo

    "Indeed, not!!"

  12. #27
    creinys
    Guest
    Bo, that was a real good and clear lesson on resurround. The pics are great.
    I may tackle it on the 125A, was not a LE-15. I was wrong. What model is the mid, high on a decade 36? Could not find in library. Thanks Bo, Chet

  13. #28
    RIP 2014 Ken Pachkowsky's Avatar
    Join Date
    Apr 2003
    Location
    Baja, Mexico
    Posts
    1,706

    Bo

    Nice job. I do believe I recognized those 2122H's.

    Ken

  14. #29
    transducergeek
    Guest
    Quote Originally Posted by creinys
    Bo, that was a real good and clear lesson on resurround. The pics are great.
    I may tackle it on the 125A, was not a LE-15. I was wrong. What model is the mid, high on a decade 36? Could not find in library. Thanks Bo, Chet
    Hi Chet. If you mean an L36 3 way system? I had one and it used a LE5-5? midrange 5 incher for the High/mid unit. and a LE25-2? 1.4 inch tweet. And the 127A? 10" woofer.. This is from memory, I could be wrong..I sold the units about 3 months ago after re-surrounding the woofs and fully cleaning the rest, Poorly stored when I obtained it from someone who just did'nt care, it was filthy with actual mud on the veneer/grille, not kidding..... A nice "rescue" job. Now in the home of a music lover and hooked up to an old Fischer tube job and the new owner loves it! Makes one's heart feel good..


    Thanks to all the Forum, guy's..
    Rolf E.

  15. #30
    Senior Seņor boputnam's Avatar
    Join Date
    Apr 2003
    Location
    northern california
    Posts
    7,007
    Yea, transducergeek - thanks for the help.

    I missed this whole exchange , but smartly, Chet started his own L36 Decade Thread, and the guys that know the line came-in with part numbers and the rest.
    bo

    "Indeed, not!!"

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Recone or Resurround!!
    By whej4312 in forum Lansing Product General Information
    Replies: 8
    Last Post: 07-08-2004, 07:08 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •