- 1960s-1970s Telephone Repair - 22 Updates
- Membrane keypad problem - 2 Updates
- Vintage Fisher TX-300 Integrated needs caps - 1 Update
| "J. B. Wood" <john.wood@nrl.navy.mil>: Apr 10 04:12PM -0400 Hello, all, especially those with familiarity with subject. I've got a decades-old Stromberg-Carlson SC-2554 wall mount phone. It's still in great shape except recently a small white piece of plastic on the make/break hook switch broke rendering the rest of the cradle mechanism inoperative. The plastic piece finally broke from the tension from the return spring. It's a clean break but I'm afraid that even if I can glue the pieces back together it will most likely fail again in short order. Thanks for your time and your comment is most appreciated. Sincerely, -- J. B. Wood e-mail: arl_123234@hotmail.com |
| Baron <baron@linuxmaniac.net>: Apr 10 09:25PM +0100 J. B. Wood prodded the keyboard with: > fail again in short order. Thanks for your time and your comment is > most appreciated. > Sincerely, You could always try a steel pin heated hot enough to sink into the plastic, a bit like a staple, or cross drill it and press a staple in the holes. -- Best Regards: Baron. |
| Jeff Liebermann <jeffl@cruzio.com>: Apr 10 01:42PM -0700 On Sun, 10 Apr 2016 16:12:40 -0400, "J. B. Wood" >glue the pieces back together it will most likely fail again in short >order. Thanks for your time and your comment is most appreciated. >Sincerely, Glue the broken parts back together but do NOT reinstall them in the phone. Instead, find someone with a 3D digitizer and 3D printer who can make a reproduction of the original. I'm not familiar with SC phones, but the equivalent part in a Western Electric wall phone is a flat plate with two rectangular holes. That can probably be machined out of plastic. I couldn't find a photo with Google Images. Are you sure about the model number? The SC number was SC-554 while the WE number was 2554. SC-554: <https://www.youtube.com/watch?v=cDP6I8bEP8o> WE 2554: <https://www.youtube.com/watch?v=VedsBJfsLlo> -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
| dansabrservices@yahoo.com: Apr 10 03:25PM -0700 There is a line of products of which Plastic-Weld is one that I have used with much success over the years for similar types of problems. This is a solvent based "glue" that actually dissolves the plastic a bit and reforms it. The joint essentially disappears. Caution though, don't press together too much or you will deform the plastic. Only apply enough pressure to be sure that the two parts meet firmly. Dan |
| Don Y <blockedofcourse@foo.invalid>: Apr 11 04:13AM -0700 On 4/10/2016 1:12 PM, J. B. Wood wrote: > clean break but I'm afraid that even if I can glue the pieces back together it > will most likely fail again in short order. Thanks for your time and your > comment is most appreciated. Sincerely, Your description is vague. Is the plastic piece part of the housing? Or, a mechanical actuator that conveys the hookswitch's state to the actual switch? Said another way, does the phone *appear* (visually) to be intact -- but, some INTERNAL mechanism is broken that allows it to FUNCTION as it should? (Could you, perhaps, post a picture on a hosting site with a link, here?) |
| "J. B. Wood" <john.wood@nrl.navy.mil>: Apr 11 07:23AM -0400 On 04/10/2016 04:42 PM, Jeff Liebermann wrote: > <https://www.youtube.com/watch?v=cDP6I8bEP8o> > WE 2554: > <https://www.youtube.com/watch?v=VedsBJfsLlo> Thanks for the response, Jeff. The number stamped on the back of the instrument is S-C 2554BPM. Perhaps the "2" designated a DTMF type dial? Sincerely, -- J. B. Wood e-mail: arl_123234@hotmail.com |
| "J. B. Wood" <john.wood@nrl.navy.mil>: Apr 11 08:33AM -0400 > Only apply enough pressure to be sure that the two parts meet > firmly. > Dan Thanks for the follow-up, Dan. Are you referring to one of the products from http://www.jbweld.com/collections/plastic-composite-pvc? If so, is there a specific one from this company that you can recommend? Thanks. Sincerely, -- J. B. Wood e-mail: arl_123234@hotmail.com |
| "J. B. Wood" <john.wood@nrl.navy.mil>: Apr 11 08:41AM -0400 On 04/11/2016 07:13 AM, Don Y wrote: > Said another way, does the phone *appear* (visually) to be intact -- but, > some INTERNAL mechanism is broken that allows it to FUNCTION as it should? > (Could you, perhaps, post a picture on a hosting site with a link, here?) Hello, and yeah, I kind of figured that might be a problem. It's just a small piece of plastic that separates the electrical contacts on the hook switch. A small shaft which passes through the plastic piece upon which a spring-loaded bracket pivots. This bracket makes contact with the arm that determines whether the handset is on or off the cradle. The plastic split right where that small shaft passes. Sincerely, -- J. B. Wood e-mail: arl_123234@hotmail.com |
| "pfjw@aol.com" <pfjw@aol.com>: Apr 11 05:43AM -0700 On Sunday, April 10, 2016 at 4:12:44 PM UTC-4, J. B. Wood wrote: > Sincerely, > -- > J. B. Wood e-mail: arl_123234@hotmail.com Mpfffff... take out the part. Put it back together with JB Weld - available everywhere. Be sloppy with the material, but make sure that you do not glue the part to anything else. I will on occasion tie such a part together with fine thread (if there are holes through it, even better) and suspend it during the curing process. Then with files, X-Acto and sandpaper, reshape the part to its correct size, removing flash and sprue, so to write. Re-drill any filled holes and you are done. JB Weld will be harder and stronger than the OEM plastic by a considerable margin. Peter Wieck Melrose Park, PA |
| Chuck <chuck@mydeja.net>: Apr 11 08:22AM -0500 On Sun, 10 Apr 2016 16:12:40 -0400, "J. B. Wood" >glue the pieces back together it will most likely fail again in short >order. Thanks for your time and your comment is most appreciated. >Sincerely, I have had good luck with some plastic parts using Gorilla super glue. --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus |
| "pfjw@aol.com" <pfjw@aol.com>: Apr 11 06:53AM -0700 On Monday, April 11, 2016 at 9:22:11 AM UTC-4, Chuck wrote: > On Sun, 10 Apr 2016 16:12:40 -0400, "J. B. Wood" > I have had good luck with some plastic parts using Gorilla super glue. In most cases, I would suggest super glue - Gorilla or otherwise. But many phone parts are made from Delrin® (Polyoxymethylene), which also happens to be one of the materials used to deliver super-glue as it does not stick to Delrin. I am not stating that this particular part is Delrin - but a great many friction and contactor parts are made from that material because of its self-lubricating and excellent insulating properties. Further to this, it naturally repels metallic dust and powder, such as could build up and arc. JB Weld *does* stick to Delrin reasonably well, and has enough self-integrity to bridge and fill. Peter Wieck Melrose Park, PA |
| dansabrservices@yahoo.com: Apr 11 07:30AM -0700 The product I am referencing is NOT JB-Weld. The product is made by Plastruct and is called Plastic Weld. It is a clear liquid not an epoxy that actually dissolves the plastic and allows for reformation. It is considered a plastic solvent and cement. Dan |
| "pfjw@aol.com" <pfjw@aol.com>: Apr 11 07:54AM -0700 > The product I am referencing is NOT JB-Weld. The product is made by Plastruct and is called Plastic Weld. It is a clear liquid not an epoxy that actually dissolves the plastic and allows for reformation. It is considered a plastic solvent and cement. > Dan Dan: If that part *is* Delrin, it will be entirely impervious to Plastic Weld. As will be many high density, self-lubricating plastics. The material you suggest is useful on the polystyrene/acrylic based materials, not so much on others. Peter Wieck Melrose Park, PA |
| Jeff Liebermann <jeffl@cruzio.com>: Apr 11 09:06AM -0700 On Mon, 11 Apr 2016 07:23:49 -0400, "J. B. Wood" >Thanks for the response, Jeff. The number stamped on the back of the >instrument is S-C 2554BPM. Perhaps the "2" designated a DTMF type dial? >Sincerely, Ah, that's a better number. There's one for sale on eBay if you need parts: <www.ebay.com/itm/STROMBERG-CARLSON-2554-BPM-Wall-Mounted-Single-Line-Corded-Phone-/281979044418> It's impossible to get into a discussion on adhesives without everyone recommending their favorite potions, concoctions, and methods. I'll just make things worse. My guess(tm) is that the plastic in the phone is probably ABS (acrylic butyl styrene) which will weld nicely with acetone solvent. There are overpriced potions available that are mostly acetone, but might include other solvents (MEK, toluene, etc). <http://nerfhaven.com/forums/topic/18527-intro-to-solvent-welding-plastic/> Superglue (cyanoacrylate) is too brittle and mutilates acrylics. <http://info.craftechind.com/blog/bid/323475/Stick-to-it-A-Guide-to-the-Best-Glue-for-Plastic> Urethane adhesives, such as Gorilla Glue, don't do well with many plastics because they do NOT contain any solvents. Fortunately, the phone switch insulator (or whatever it's called) sees force in only one direction, so marginal adhesives will probably work, for a while. Just to muddy the waters, I've been learning plastic welding using some home made brass nozzles attached to my SMT desoldering station hot air gun. When it works, it works great. When I do something wrong, it destroys the part. Plastic welding works best for me on large plastic parts, and not so good on small plastic parts. I'm also a fan of hot melt glue, but that's not appropriate for this job. However, if you do decide to try hot melt glue, be sure to get the correct type of adhesive stick: <https://en.wikipedia.org/wiki/Hot-melt_adhesive> Good luck. -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
| Jeff Liebermann <jeffl@cruzio.com>: Apr 11 09:22AM -0700 On Mon, 11 Apr 2016 07:30:34 -0700 (PDT), dansabrservices@yahoo.com wrote: >not an epoxy that actually dissolves the plastic and allows for >reformation. It is considered a plastic solvent and cement. >Dan A URL is amazingly helpful: <http://www.amazon.com/Plastruct-Plastic-Weld-applicator-2oz/dp/B00FDFWJD8> The MSDS at: <http://plastruct.com/wp-content/uploads/2015/06/MSDS_PPC_2.pdf> says that it's: Methylene Chloride (Dichloromethane) 80-90% Methyl Ethyl Ketone (MEK) 5-15% Yep, that will certainly work for ABS, PVC, and various styrene plastics. However, methyl chloride is rather dangerous. The EU banned the stuff in 2011. It was commonly used for furniture stripper before it was recognized as hazardous: <https://www.cdph.ca.gov/programs/hesis/Documents/MethyleneChlorideAlert.pdf> Suggestion: Use the stuff outdoors and wear the usual protection (breather, glasses, gloves, etc). Plastruct video: <https://www.youtube.com/watch?v=979eXts6DwM> (1:23) -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
| etpm@whidbey.com: Apr 11 09:51AM -0700 On Sun, 10 Apr 2016 16:12:40 -0400, "J. B. Wood" >glue the pieces back together it will most likely fail again in short >order. Thanks for your time and your comment is most appreciated. >Sincerely, I don't know what kind of plastic your part is but there is a two part plastic cement that bonds well to many of the plastics that are hard to glue. I don't remember the name but I think it is made by Loctite which has lots of epoxies and the like at hardware stores. Anyway, the stuff is made specifically for plastic repair, not general repair jobs like JB Weld (which is pretty good stuff) and 5 minute epoxy and the like. I have used the stuff and it worked very well. Smelled bad when curing but no smell once cured. I even used it in a test repair. The radiator in our Toyota Camry developed a crack in the upper plastic part of the radiator. I ordered a new radiator and while waiting for it tried this plastic repair stuff. I cleaned and roughed up the plastic, slathered on the glue, then I laid a piece of cloth which was saturated with the glue on top. After it set the car was driven for a couple weeks before I replaced the radiator. The patch never gave up and the radiator got hotter than the recommended highest temperature for the glue. I don't know how long the patch would have lasted but since it was on the car I installed the new radiator. Eric |
| Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Apr 11 02:03PM -0400 On 04/11/2016 12:22 PM, Jeff Liebermann wrote: > (breather, glasses, gloves, etc). > Plastruct video: > <https://www.youtube.com/watch?v=979eXts6DwM> (1:23) Methyl chloride (CH3Cl) != methylene chloride (CH3Cl2). The stuff with the shorter name is pretty evil, but the longer stuff you can practically drink. (Just joking, kids. Don't drink paint remover.) Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net |
| Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Apr 11 02:04PM -0400 On 04/11/2016 02:03 PM, Phil Hobbs wrote: > practically drink. (Just joking, kids. Don't drink paint remover.) > Cheers > Phil Hobbs CH2Cl2. -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net |
| Jeff Liebermann <jeffl@cruzio.com>: Apr 11 11:48AM -0700 >I don't know what kind of plastic your part is but there is a two part >plastic cement that bonds well to many of the plastics that are hard >to glue. I don't remember the name but I think it is made by Loctite <http://www.loctiteproducts.com/p/sg_plstc/overview/Loctite-Plastics-Bonding-System.htm> Cyanoacrylate resin and MEK as "activator". Works quickly and great for most plastics. However, the MEK tends to dry out prematurely in the bottle. Have some extra MEK handy if you're going to use it. Also, make sure everything is free of grease or it won't stick. -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
| Jeff Liebermann <jeffl@cruzio.com>: Apr 11 11:50AM -0700 On Mon, 11 Apr 2016 14:03:54 -0400, Phil Hobbs >Methyl chloride (CH3Cl) != methylene chloride (CH3Cl2). The stuff with >the shorter name is pretty evil, but the longer stuff you can >practically drink. (Just joking, kids. Don't drink paint remover.) Oops. Thanks for the correction. I thought they were the same stuff. >Cheers Grumble... Jeff L. -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
| etpm@whidbey.com: Apr 11 12:07PM -0700 On Mon, 11 Apr 2016 11:48:37 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote: >for most plastics. However, the MEK tends to dry out prematurely in >the bottle. Have some extra MEK handy if you're going to use it. >Also, make sure everything is free of grease or it won't stick. Greetings Jeff, The stuff I'm talking about is not a cyanoacrylate resin and activator system. It is two parts that must be mixed and then applied. This is the stuff. I think. See the link: http://www.homedepot.com/p/Loctite-0-85-fl-oz-Plastic-Epoxy-1360788/100371824 Eric |
| etpm@whidbey.com: Apr 11 12:09PM -0700 On Mon, 11 Apr 2016 09:06:48 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote: >the correct type of adhesive stick: ><https://en.wikipedia.org/wiki/Hot-melt_adhesive> >Good luck. ABS=Acrylonitrile butadiene styrene. |
| bitrex <bitrex@de.lete.earthlink.net>: Apr 11 12:05AM -0400 One final problem I've been having with this synthesizer restoration project for a friend. I've reassembled the synthesizer and noticed that the membrane switches on the front panel weren't functioning properly. I traced it back to a certain connector on the board - when I tug upwards on the wires leading to the header the buttons function normally, but when I relax them slack and let everything rest normally the buttons stop functioning again. I've lifted up the board and tested continuity between the soldered PCB pins and the points where the wires from the membrane button board enter the detachable header while connected and everything tests fine, so I'm not exactly sure what the problem is... |
| N_Cook <diverse@tcp.co.uk>: Apr 11 04:30PM +0100 On 11/04/2016 05:05, bitrex wrote: > pins and the points where the wires from the membrane button board enter > the detachable header while connected and everything tests fine, so I'm > not exactly sure what the problem is... Assuming an indirect connector, try cleaning contact surfaces and then pack out the reverse side with some mica sheet |
| ohger1s@gmail.com: Apr 09 02:51PM -0700 Looking for advice on replacing coupling capacitors in this circa 1964 N.Y. built amp. I picked it up some 20 years ago in a pile of stuff and it worked when I tried it, but my son wants to use it with a turntable and she barely makes a peep now. I found a whole batch of 4uf W.German electros totally inert, and need to replace them. I'll need at least 15 but don't want to break the bank on an amplifier of dubious value, particularly since it's all germanium and some blown outputs would probably end it's useful life. My son loves it because of it's looks, and it is very well made otherwise. So instead of putting electrolytics back in, I was thinking of putting in some film caps. Is there a relatively cheap film cap or should I just stay with electrolytics, and if so, which? I found these on DigiKey which are reasonable: http://www.digikey.com/product-detail/en/kemet/R82CC4470Z330J/399-11511-ND/4833337 Another anomaly is that while the schematic calls out mostly 4uf caps, this particular unit has two locations that have 10uf installed on each preamp board, everything is the same as the schematic. Strangely, although they're the same 10uf value and voltage, the two locations have two different manufacturers. The other twin preamp board has the same exact two caps in the same exact spot, as if they were selected for voicing reasons. Service manual here: http://www.fisherconsoles.com/non%20console%20manuals/fisher%20tx300%20begin%2010000%20sm.pdf And since 4uf caps are pretty much made of unobtainium, should I go to 4.7 or 3.3, or should I cobble some together? |
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