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+--- Thread: how to reseal a 41C module (/thread-18931.html)
how to reseal a 41C module - dmh - 10-04-2022 12:35 PM
I have a 41C HP IL module that it appears someone has tried to crack open.
The module actually still works and plugs into the 41C fine but needs to be squeezed together carefully as you are doing it so I'd like to make it safer and sturdier to use by sealing it back together somehow.
Can anyone recommend a glue or similar to do this?
I know many glues can damage plastic and this is old plastic so want to check with here first as I have never glued any part of a 41C or peripheral before.
TIA, dmh
RE: how to reseal a 41C module - Dave Britten - 10-04-2022 02:03 PM
If you want to do it the quick-and-dirty-but-safe way, you could always just wrap a little kapton tape around it. If I had to glue one back together, though, I'd probably go with a very light application of JB Weld Plastic Bonder.
RE: how to reseal a 41C module - BillBee - 10-04-2022 04:42 PM
I've used E6000 adhesive for a couple 28S' which had case separation. Clamp well and let it sit overnight. Not overly pretty but holds well.
Ironically I too have a HP-IL which had been cracked open. Its detected and "cat" lists fine but a closed loop "prx" ends in a transmission error - probably why it was opened. As such, I haven't sealed it yet.
-Bill
RE: how to reseal a 41C module - rprosperi - 10-05-2022 02:21 AM
I've found E6000 is a good easy to apply overall glue for many plastic repairs, but I agree with Dave, I've found JB Weld Epoxy to be the best for this type of repair where only a tiny amount is desired to hold parts together, but without being too visible or interfering with the case shape and size. I have used this to glue 41 and 71 module cases together, it works perfectly.
JB Weld comes in many flavors, and even the instant-drying type works better than expected, but I'd say use the normal quick-drying type (like this: https://www.amazon.com/J-B-Weld-ClearWeld-Syringe-25mL/dp/B09C6R4VSQ). This a true, 2-component epoxy, but the dual chamber syringe makes it easy to dispense, and be sure to mix the two types very well, then apply sparingly, clamp and let it dry untouched for 24 hours. It's amazing stuff.
RE: how to reseal a 41C module - dmh - 10-06-2022 01:47 AM
Thank you everyone for your replies.
Here is a photo if it helps.
I definitely tested CAT 2 and I thought I tested the module too but can't recall now as it was a while ago when I received it. Why would anyone do this otherwise though?
Inline image doesn't appear to work so here is the link also:
https://www.dropbox.com/s/a6yhj58jsdz6l8n/Split%20IL%20Module.jpg?dl=0
![[Image: Split%20IL%20Module.jpg?dl=0]](https://www.dropbox.com/s/a6yhj58jsdz6l8n/Split%20IL%20Module.jpg?dl=0)
RE: how to reseal a 41C module - BillBee - 10-06-2022 11:09 AM
As is the situation with mine, I assumed it was opened to check the continuity of the cables.
My understanding is that if Cat 2 is fine but a transmission error occurs (with the leads connected together) then the next step is to check if the cables are good.
-Bill
RE: how to reseal a 41C module - MeindertKuipers - 10-06-2022 01:20 PM
(10-06-2022 11:09 AM)BillBee Wrote: As is the situation with mine, I assumed it was opened to check the continuity of the cables.
My understanding is that if Cat 2 is fine but a transmission error occurs (with the leads connected together) then the next step is to check if the cables are good.
-Bill
I had a similar issue with my HP-IL module that I purchased a few years ago. CAT 2 was fine, but no communication. After a long search I was able to locate a broken wire from the transformer to the PCB soldering, and fortunately I was able to resolder this wire, and I then had a fully working IL module.
So you need to check the cable continuity and if that is OK verify continuity of the transformer coils in all possible combinations and visually inspect the soldering (with a good magnifier glass).
RE: how to reseal a 41C module - BillBee - 10-06-2022 02:11 PM
(10-06-2022 01:20 PM)MeindertKuipers Wrote:(10-06-2022 11:09 AM)BillBee Wrote: As is the situation with mine, I assumed it was opened to check the continuity of the cables.
My understanding is that if Cat 2 is fine but a transmission error occurs (with the leads connected together) then the next step is to check if the cables are good.
-Bill
I had a similar issue with my HP-IL module that I purchased a few years ago. CAT 2 was fine, but no communication. After a long search I was able to locate a broken wire from the transformer to the PCB soldering, and fortunately I was able to resolder this wire, and I then had a fully working IL module.
So you need to check the cable continuity and if that is OK verify continuity of the transformer coils in all possible combinations and visually inspect the soldering (with a good magnifier glass).
Thank-you Meindert!
-Bill
RE: how to reseal a 41C module - GreyUser - 10-10-2022 04:36 AM
Any HP calculator plastic parts needing repair should always be done solvent welding cement. It’s a clear, water like liquid sold in hobby stores for the assembly of plastic models. It is far superior to any other adhesive since it fuses the pieces together, the bond is as strong as the plastic itself. There is nothing better for 41 post and case repairs.
JB weld is great where you need to fill gaps but be aware that it can be slightly conductive. When you have repairs without gaps, or especially cracks, solvent welder gives a better result.
RE: how to reseal a 41C module - BillBee - 10-10-2022 11:06 AM
(10-10-2022 04:36 AM)GreyUser Wrote: Any HP calculator plastic parts needing repair should always be done solvent welding cement. It’s a clear, water like liquid sold in hobby stores for the assembly of plastic models. It is far superior to any other adhesive since it fuses the pieces together, the bond is as strong as the plastic itself. There is nothing better for 41 post and case repairs.
JB weld is great where you need to fill gaps but be aware that it can be slightly conductive. When you have repairs without gaps, or especially cracks, solvent welder gives a better result.
Thanks for the advice. Can you give a specific product name that you have used?
-Bill
RE: how to reseal a 41C module - dmh - 10-10-2022 11:17 AM
I used to build model planes etc when I was a kid. I assume the glue is basically the same these days? Is there a particular compound/active ingredient to look for?
It was such a long time ago I hadn't even though of that.
Just confirming, you've used this on calculators / the 41 (sounds like it)?
Thanks
(10-10-2022 04:36 AM)GreyUser Wrote: Any HP calculator plastic parts needing repair should always be done solvent welding cement. It’s a clear, water like liquid sold in hobby stores for the assembly of plastic models. It is far superior to any other adhesive since it fuses the pieces together, the bond is as strong as the plastic itself. There is nothing better for 41 post and case repairs.
JB weld is great where you need to fill gaps but be aware that it can be slightly conductive. When you have repairs without gaps, or especially cracks, solvent welder gives a better result.
RE: how to reseal a 41C module - Dave Britten - 10-10-2022 01:12 PM
(10-10-2022 04:36 AM)GreyUser Wrote: Any HP calculator plastic parts needing repair should always be done solvent welding cement. It’s a clear, water like liquid sold in hobby stores for the assembly of plastic models. It is far superior to any other adhesive since it fuses the pieces together, the bond is as strong as the plastic itself. There is nothing better for 41 post and case repairs.
JB weld is great where you need to fill gaps but be aware that it can be slightly conductive. When you have repairs without gaps, or especially cracks, solvent welder gives a better result.
That will certainly seal it up quite permanently, but you're going to have quite a job on your hands if you ever need to open the module up again later.
For stuff that's not supposed to open/separate, like cracked screw posts, I definitely agree though.
RE: how to reseal a 41C module - dmh - 10-11-2022 10:38 AM
So something like this? It's available at a local supplier.
https://www.metrohobbies.com.au/products/revell-cement-professional-glue-for-plastics-models-25g
I'll need to find something to clamp it with too.
I've tested the module again and can see mass storage so it's worth fixing.
RE: how to reseal a 41C module - GreyUser - 10-13-2022 02:08 AM
In the USA:
https://www.amazon.com/Plastruct-Plastic-Weld-applicator-Bottle/dp/B00FDFWJD8/ref=asc_df_B00FDFWJD8
https://www.micromark.com/Same-Stuff-Professional-Plastic-Welder-Refill-2-fl-oz-_2
The stuff is probably methyl ethyl ketone (MEK) plus additives to slow the evaporation rate a bit. I say this because I’ve tried straight MEK and it doesn’t work as well as what I buy as model cement.
I use the Plastruct product. If you can find that name, be sure to get the orange label product. There is a white label product that does not work as well as the orange, it may be for California, not sure but I know it’s not up to the task of post repairs.
I would not buy any product that you cannot see that the consistency and color is the same as water. There had been another product in the US called Tenax 7R but that is not longer available.