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Plastic Injection Molding

So I work for a very small biomedical startup company who rents space on top of a plastic injection molding company. I keep thinking this has to be useful in some way. What are some Esk8 pieces that the community thinks would be a good fit? I’m a moderately good Solidworks user but would love insight from some of the pros here. A general mold for something costs around $2,000 as the startup to CNC the mold out but then the actual infills get real cheap. We currently use them to manufacture our MRSA test cassette and their quality is good. 20181205_104844 If any suppliers on here want some quotes or want me to ask some questions let me know if I can be of any help.

Edit: General starting mold is around $3,000 my mistake.

Website of molding company


Firefly remote casings and derivatives


How about wheels? But the testing to find a good untherane formula is going to be expensive probably

I have a friend that works at school as a professor and he has an access to a cnc miller, idk what tools it has but it could be a way to get a very cheap mold, but only one probably since its kinda tricky for him to make stuff like this

Make variations of those freebord bindings that everybody wanted…


Almost forgot about those

I thought about making a mold of gears at one point.

A injection moulded enclosure would be awesome. That would have a fairly big so expensive mould though.

Is there any reason people aren’t just 3d printing them for themselves? They seem like a preference buy. That being said I do like them a whole whole bunch

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What about injection moulded compression packs? Or screen displays for the davega or whatever it’s called. Maybe even XT90s plug holders

Really it’s the start up cost of the mold. I can’t drop 3 to 5 thousand dollars on something that already exists. I’m looking to make 35° aircraft grade aluminum rider wedges currently as well (for a reasonable price). Need to test one out myself first!

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lol, how can you call this thing good quality

Excuse yourself?


I’d love a fiberglass reinforced nylon slip on pulley like enertion but molds are expensive and youd need a new mold for every different tooth count so no feasible.

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I wonder if @onloop still owns that 36t pulley mold maybe he can sell the mold if he’s not using it anymore lol

well, let me get this straight. i am not attacking this product, i am criticizing the process. I think the company right under yours did the mould and the design of the part. maybe you gave them details or sketches how it should look like.

i will now give you some facts, why this is bad quality:

First: Shrink marks/sunk spot means that there is a mass accumulation, generally occurs at edges or too much difference at the wall thicknesses.

Second: Sunk spots around the characters means badly placed ribbing or difference at wall thicknesses

Third: Burn marks could be originate from missing ventilation, its called “diesel-effekt”, but i cant really identify it because of the image quality. could also be from missing cooling in the mould/to hot ejecting. all in all the surface does not look smooth like the rest



You make these claims with no knowledge of application, restrictions, or what’s on the underside of that cassette. You don’t know material used, pre treatment conditions, or our tolerance specs.

Now this is where most assholes would unleash whatever pent up fury they’ve accumulated from the day.

I would like to sincerely thank you for your opinion and concern for the product. You are clearly knowledgeable in the area and are willing to offer suggestions.

Now back to the approach… Criticism and negativity. I immediately have a bad taste for you in my mouth and most likely will for quite some time. I’ve developed this product for the past 5 years with a team of 4 people and we’re on track through FDA trials developing very helpful diagnostic tests. We’re locked into this mold design as it’s what we started trials with and would have to restart with a new design.

Consider this:

If your second statement was your first, I’d have an immense level of respect and appreciation for you.

I don’t read books by their cover, but the intro usually paints a good picture of how the novel plays out.

I sincerely hope we can be cordial in the future, you seem generally intelligent in this area that I am still learning. :smiley:


well, excuse my first written statement.

as i said, i am not attacking the product by itself, nor you. a matter of fact is, that this “plastic housing” is badly designed. I know it is not relevant to the function. since it is a cassette that is put inside a detector… or sth. like this… right?

well, tolerance is matter of interpretation - if the function is not affected, it doesnt really matter…

but you want to let these guys make technical things, or maybe things that keep people safe (talking about trucks… wheels, hangers idk.) now this is the point where tolerances are getting important. if their process does not fit the part (try a higher holding pressure (100bar maybe?)) then we can get very fast very bad parts (see MBS II Matrix trucks - weld line problems because of bad design)

Since you’re getting an FDA trails, i would say this is polypropylene or polyethylene. pre treatment would be a simple 3-4 hour vaccum drying of the pellets, be carefully to not overdry. And for this part the tolerances would be not so important.

so call me anything you want, but this housing is badly designed, regardless the function it fulfills. if you have questions, feel free to ask.


Badly designed or badly moulded? Full disclosure, one of those answers will get you punched directly in the face if I ever meet you.

Choose your words carefully. I designed that test cassette, I didn’t mould it.


Just to be clear I only called you knowledgeable and intelligent.


What’s with the threats…

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