Hi.
My MPC Live took a minor whack to the top case, on the side and there’s now a small hole in there. I reckon I could fill it.
Anyone used plastic filler on such things? Worth trying, before something catches it and makes it a bigger hole?
Can you either post a close-up picture of the damage or send one to me? I’m just a hobbyist but I could probably give you a couple tips about products or DIY type plastic repair, but it depends on what things are looking like and how detail oriented you want to be about the repair.
You may in fact need to drill the hole out to make it more uniform and easier to repair, but I just don’t know without more details. I also don’t know what kind of plastic the case is made out of, probably ABS, but plastic type tends to matter in how you go about the repair.
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Ta! I’ll try and take a photo when I get chance.
Ok, sounds good. Did a piece break off when it was damaged? Is it a flat hole or does it have some concavity? In other words, does the plastic fill need to seal a piece of it back into place or does it need to span a gap and hold with it’s own strength? Approximately what diameter is the hole and is it uniform in size or somewhat jagged like, for example, more of a star shape than a hole? Is the MPC live a black color?
I haven’t done it on a piece of gear exactly but I’ve patched plastics a few times. Like @shigginpit is saying, it’s hard to give advice specific to your situation without a picture and knowing what kind of plastic it’s made of though that can probably be looked up.
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duct tape
Is that the front side of the unit (below the face) and then the lower part of the picture would be the bottom, or is that the top? How far does that crack go under the enclosure (if that’s the bottom)? Or does it extend up onto the face (top)?
You have something of a 3 dimensional problem here because it looks like the damage taken must have hit just right to cause the crack to travel in both directions.
If you want to improve the appearance, you’ll need to remove the housing and then carefully use small diamond files, or I guess sometimes called needle files, to level out the jagged part (in between the cracked edges) a bit in order to get them to fit together better.
It does not look like there is a big enough gap or hole to where you’d have any problem bonding it together without any additional backing material so that’s good.
If your goal is entirely just to make it more structurally strong, you could probably use scigrip 16, it’s compatible with quite a few kinds of plastic and dries very solid. I’ve had good luck using this for repairs and projects, but it can be messy if you aren’t careful.
Another thing you could try, is just using Methyl Ethyl Ketone (MEK) which is the primary ingredient in a lot of plastic cements. you’d have to be really careful but just brushing it on with a fine brush or using it in a dropper should melt that crack together.
Using straight MEK will probably be even messier than plastic cement though.
There are instances where you can use a soldering iron and some compatible plastic (like for example a zip tie) and do spot repairs, but I’m still not sure what the case is made of so I wouldn’t do that before determining if it’s a thermoset or thermoplastic.
It really depends on how clean you want the repair to be that will determine the amount of work, but I’d say at least look into availability for ordering Scigrip 16 in your area, and then just use a little bit to practice on some different plastic before you move on the the MPC case.
https://www.scigripadhesives.com/scigrip-16-low-voc-acrylic-plastic-cement/
This product works on quite a few polymers and sets relatively quickly, but it’s very permanent and it’s not an adhesive really, it’s a chemical which causes plastics to sort of melt and bond to each other in a very controlled way, so you have to be very careful (MEK works similarly but it’s less precise, plus a lot messier to apply and use).
If you have more questions, I’ll try and do what I can to answer them.
I don’t recommend things called like, superglue for plastics or any of those, I tried a few and they’re kind of a waste of money. You aren’t using it to hold something together against the force of gravity (which is good) but I would not use the products which are really inexpensive and say bonds plastic because they never work correctly (in my experience).
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I was expecting a sizable hole and figured the repair would be about embedding a lattice and figuring out what kind of resin to make/ fill with but this does look like a rebonding job.
My inclination would be toward mek like @shigginpit mentioned but I’ve never tried scigrip16 so can’t really weigh in on it as a more user friendly alternative.
If for whatever reason you do want to go the adhesive route rather than the vulcanization/ welding route there are more serious types of CA (cyano acrylate) adhesives that would probably work. They’re like super glue for construction and require a separate activator. I’m not necessarily recommending going that route since it’s still a little messy and not as strong as melting the plastic back together (but probably strong enough), and you would need to get the bonding surfaces very clean.
There is certainly an epoxy that would do the job too but unless you’ve worked with it before I wouldn’t recommend it for such a delicate job.
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The number 16 formula of Scigrip is has a little bit more tack to it so it can do a bit of fill in, MEK will work just as well and weld the hell out of it, but the tolerances generally need to be a little tighter.
Scigrip isn’t as thick or messy as using an ABS slurry, but more like testors model cement compared to cyano acrylate, where super glue is almost always a bit watery and plastic cement has a slight body to it. Probably not enough to span a flat gap, but enough to fill a deep crack.
This is the only picture I have on hand of a scigrip weld (used with clear PVC) but I’ve used it with numerous types of plastic and have had a good rate of success. I imagine the primary ingredient is MEK, and I do recommend getting used to the way it flows before using it for the actual repair. Also, using a hobby syringe for distribution into cracks would be a good way to save product and make the application more precise.
You can probably tell from the picture that the application can be controlled nicely and doesn’t suffer from spill over. It’s also a bit more forgiving of the bonding surfaces not being 100% flush with each other. These dividers I made for my refrigerator door have slots that fit the 2 PVC pieces into place and I used the scigrip to bond them permanently.
There was still some gap (as cut) and in this instance scigrip turned the junction into a solid joint.
It’s also very strong, I saw some tests comparing the force which it takes to break a scigrip bond vs CA glue and scigrip took a lot more force to shatter the joint.
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