TM503 plug-in... broken removal lever/tab/pull, help! - Page 1
Forum section: electronics / testgear

author: worsthorse
author_rank: Super Contributor
timestamp: February 20, 2019, 04:54:28 am
content: I picked up a Tektronix TM503A frame with four plug-ins this weekend. While removing one of the plug-ins from the frame, the release tab came off in my hand and now the plug-in is stuck. I tried getting a thin screwdriver in between the catch and the frame. No joy.I gotta believe that someone else has had this problem... Any suggestions or tips on freeing the plug-in from the frame? Thanks!

author: Rerouter
author_rank: Super Contributor
timestamp: February 20, 2019, 05:31:12 am
content: Either remove the plugin next to it to access to side panel to access the latch. Or remove the side from the mainframe to do the same

author: worsthorse
author_rank: Super Contributor
timestamp: February 20, 2019, 05:51:37 pm
content: arrgh... i am terribly slow witted sometimes. thanks for the help.i forgot that they weren't screwed on. i was able to remove the side panel of the plug-in and get access to the catch.now i need to find a junker plug-in i can use for parts. i knew i should have bought a couple at the hamfest.bill

author: Neomys Sapiens
author_rank: Super Contributor
timestamp: February 20, 2019, 10:02:27 pm
content: Quote from: wch on February 20, 2019, 05:51:37 pmThe protruding part of the release tab can be exchanged, but that might be dependent on the version.Somewhere on this forum there was a link to 3D-printer data for that part.When it happened to me, I used a pin vise with a small drill to make a hole in the center of the tab and then I screwed a small cutting screw into it.

author: texaspyro
author_rank: Super Contributor
timestamp: February 21, 2019, 03:40:38 am
content: There was a guy selling them on Ebay. I think his were laser cut out of sheet plastic. Also there are 3D printed ones.

author: worsthorse
author_rank: Super Contributor
timestamp: February 24, 2019, 01:54:28 am
content: Thanks. Ebay here I come...

author: CatalinaWOW
author_rank: Super Contributor
timestamp: February 24, 2019, 04:30:10 am
content: Easiest way to get the plug in out is to remove the small screw right below the pull tab. This disconnects the latch from the frame and you can pull the module out.Here is a link to how to make your own tab in a couple of minutes.https://www.eevblog.com/forum/repair/tektronix-500-series-latch-repair/msg1076475/#msg1076475

author: CatalinaWOW
author_rank: Super Contributor
timestamp: February 24, 2019, 06:49:39 pm
content: This question got me off top dead center and I modeled the tab for 3D printing. Not a perfect match since my modeling skills aren't that good, but more than good enough.Print at high density. The model file is in .stl format, renamed to .txt to get around forum limits. Just rename it an it should be ready for your preferred slicer. It is a small part and so still takes less than 15 minutes to print. The photo makes the surface look much rougher than it actually is. If desired a little sanding can further improve the part.Cheers to all.

author: MarkL
author_rank: Unknown
timestamp: February 25, 2019, 05:45:01 pm
content: Quote from: CatalinaWOW on February 24, 2019, 06:49:39 pmNice modeling! Thanks!Some plug-ins, especially double-bay ones, need a lot of force to pull them out, and people usually pull them out by the tab (I know I do). What material are you using and/or recommend?

author: CatalinaWOW
author_rank: Super Contributor
timestamp: February 25, 2019, 06:09:11 pm
content: I used PLA just because that was what was loaded in the printer. It works fine to release the latch, but will probably have the same problem as the original if you use the tab to pull with. I would try nylon if you want the best strength possible. For me, now that replacements are easy the PLA is good enough. Well that and breaking one is good training on how not to use the pull tab.I have a few ideas to improve the model. Will post in the next few days if they pan out.

author: texaspyro
author_rank: Super Contributor
timestamp: February 25, 2019, 06:18:05 pm
content: Tek used two types of tabs. One is the type where the "fork" at the end of the tab snapped into block on the module. These are found on the smaller and earlier plugins. The second type of tab was used on later / larger modules. The module had a spring loaded mechanism to retain the pull-tab. These pull tabs a bit thicker than the other one.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: February 25, 2019, 09:58:08 pm
content: Apparently the later revision didn't break as often. I hadn't noticed it before. Did find that the TM-503 that the OP was looking for used this later version of the catch. It also does not have the screw attaching the latch mechanism that I mentioned. Probably was pretty confusing, or just thought I was an idiot. Which is probably true - sorry about the bad advice for this module.Did get the improved version of the narrow catch modeled. It has the TEKTRONIX incised in the front. Those motivated can fill this with blue ink and then wipe off the face to get a look very much like the original.Also modeled the wider and later tab since that was an easy mod of what I had already done. Since they change the font on and went to title case I don't yet have a version with the text incised.As before the two models are .stl files renamed to .txt to conform with forum limitations.

author: MarkL
author_rank: Unknown
timestamp: February 26, 2019, 02:41:53 am
content: Back on the topic of how to get a module out with a broken latch, I wanted to add that if you take the bottom off the mainframe, the slide that the latch holds onto is held by a single screw near the front. If you remove the screw, the module and the slide will come out together.I can't speak for all the chassis types, but at least my two TM503's work this way. My TM501 has a fixed bottom, but this screw is exposed.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: February 27, 2019, 01:01:19 am
content: One last addendum. I had only done one half of the fit check on the wide version of the tab. It fit fine, but I found today that it was difficult to remove. The attached file adds the incised Tektronix and changes dimensions slightly to make it as easy to remove as the Tektronix original.

author: worsthorse
author_rank: Super Contributor
timestamp: February 27, 2019, 03:17:21 am
content: That's some nice work. I don't have access to a 3D printer but will start looking. Thanks for putting so much effort into lending me a hand and I hope I can return the favor sometime.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: February 27, 2019, 02:28:16 pm
content: It benefits me too. I have a cache of these plugins and the printed tabs are much nicer than the ones made from a zip tie that I referenced in my first post.

author: worsthorse
author_rank: Super Contributor
timestamp: February 27, 2019, 03:58:05 pm
content: The work you did gave me a reason to learn more about 3D printing, a rabbit hole I've resisted going down before this. Now that I've junped, I am checking out a number of the online printing services (the services available locally are all high end and really expensive) and learning about materials and such. I have two questions for you, and promise I won't ask more!First, what's the best way to check that the dimensions of the part you made are the same as the dimensions the printing service is seeing? I ask because one of the services I looked at made an obvious scaling error when reading the STL file.Second, I am guessing that nylon would be a good choice for this part but would a glass-filled nylon be better?Thanks again for the help!

author: CatalinaWOW
author_rank: Super Contributor
timestamp: February 27, 2019, 04:58:46 pm
content: Quote from: wch on February 27, 2019, 03:58:05 pmI am not sure about how to be positive about dimensions. I have seen errors in my own work that have always been metric/English problems. Cura, one of the more widely used slicing software packages assumed metric in earlier versions, requiring manual input when using an English unit model. The latest version seems to have cured this. Apparently the units are in the .stl file if the software pays attention. My only advice when going to services would be to A: Tell them the units the part is modeled in (English/traditional/US standard). B: Tell them the dimensions of the finished part so they can see if they got it right.I am using PLA. It has been more than strong enough to meet my needs. Nylon would be stronger. I am not familiar with the properties of glass filled nylon filament. The interaction of this fill with the printing process is complicated enough that I would hesitate to predict results. Maybe someone else has experience that would shed light on this. My only experience with fiber filled thermoplastics is in more conventional molding processes, where the results are complicated and very dependent on flow into the mold, how gates and channels are arranged and so on.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: March 02, 2019, 03:34:34 pm
content: This has been a learning experience for me. The modules in the TM500 series have a number of minor variations which make my observations about the screw on the front under the tab wrong. The attached pictures of the actual mechanisms will help in determining which kind of pull tab you have. As far as I know at this time there are only two variants on the tabs themselves.Narrow tab - Tek PN 366-1690-00Wide tab - Tek PN 366-1851-01These tabs can still be found with difficulty. And for very stiff prices. I found from $15 each and up on those actually posting prices. Most just ask you to call for quotes.

author: frantisek
author_rank: Regular Contributor
timestamp: March 02, 2019, 04:41:17 pm
content: Good work!! Did not you create legs for TM 5003 or 5006? I have come up with an offer for $ 160 a piece ...

author: worsthorse
author_rank: Super Contributor
timestamp: March 02, 2019, 05:15:40 pm
content: I haven't found 366-1690-00 pull tabs for less than twenty dollars each, before shipping. Since I bought most of these plug-ins for twenty-five bucks, that seems a little much. There are a couple of folks selling laser cut tab pull replacements for much less, but it isn't clear whether they are the 1690 or the 1851 version.On the PS503A, I have a different latch (photos attached). From the manual:SN B010100 - B025429: 214-1513-0 (release), 366-1422-01 (pull tab knob), 214-1840-00 (pin)SN B025430: 105-0719-00 (release) and 366-1690-00 (pull tab)I don't have a plug-in that uses the 1851 pull tab.

author: tkamiya
author_rank: Super Contributor
timestamp: March 03, 2019, 01:49:38 am
content: I have that part. It came off of 5A21N plugin, and it looks identical to the one someone 3D printed.It is just a pull tab with tail. No other parts.If you want it, PM me. It's free.