I recently bought a "parts" SMT microscope for my new Electrical Engineering Workbench. This microscope has structural damage on a ~1/2" hinge feature at the rear of the scope where it attaches to the arm. The company (Vision Engineering) designed this scope so the hinge is part of the plastic housing of the scope - 1/2 of hinge is on left and the other is on right housing. I searched google images to try and find an example picture of the hinge; but they must know it has issues or no one has ever needed to take a picture of it. Emails with the local sales rep as only resulted in "you should send the scope in for service"... which when asked for a "ball park" repair cost... I got no response. I suspect the repair would probably cost near the amount of a new scope which defeats the purpose of buying a "for parts" scope to begin with.
I'll snap a picture tomorrow after work... after the latest JBWeld has cured.
I went thru a rather extensive "rebuild" of the hinge using some JBweld I had in the drawer. I basically re-enforced it by filling the hinge with JB weld and some #4-40 bolts to provide a clamping force. The repair worked ok for about 3-4weeks of very light usage; but came apart during use tonight. The jbweld basically didn't bond well to the hinge's plastic and couldn't handle the stress of the hinge (my guess). I've re-jbwelded the hinge tonight but honestly don't expect it to hold up very well for long.
I'd like to solicit the wisdom of my Pinball buddies ... to see what they might suggest as a rebuild advice.
At this point; JBWeld has failed me... mainly because it doesn't do a very good job of bonding the to plastic housing which I assume is made out of ABS or similar. Some people swear by JBWeld; but I haven't had a lot of success with it.
The only item turned up was a youtube video which seems to recommend 3M's EC2216 Epoxy... but that appears to be specific to the carbon fiber application.
I think some of the key limiting factors of this specific "application" are as follows:
- Scope/Housing cannot be disassembled. No service manual exists; to returning the optics to proper alignment would likely be an issue.
- Adhesive may need to bond to plastic housing
- Epoxy should be flexible while maintaining strength to plastic bond.
- May need to have fibers to aid in strength of hinge; ideally perpendicular to the hinge "crack".
My current thought was to try and do a carbon fiber re-enforcement type job on the hinge. Maybe cut some deep groves into the hinge and fill those groves with some fiber reinforced epoxy. But alas, I can't seem to find such a beast during a quick search on amazon or google. I could make a carbon fiber epoxy by mixing it into a 2 part epoxy; but wanted to see what real-world advice could be shared by our community.