How would you make this simple part?
How would you make this simple part?
(OP)
Hello,
I know nothing about plastics. I'm hoping to get some background before I walk into some local facilities. So, how would you make this part economically, either in your garage or manufactured at low volume?
The plastic needs to be rigid/resistant to gouging.
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I know nothing about plastics. I'm hoping to get some background before I walk into some local facilities. So, how would you make this part economically, either in your garage or manufactured at low volume?
The plastic needs to be rigid/resistant to gouging.
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RE: How would you make this simple part?
If you less than that many you can get a cheaper aluminium mold.
If you only need a few and can accept poor surface finish then you can try rapid prototyping, for example, contact Stratasys.
Chris DeArmitt
RE: How would you make this simple part?
I have seen injection moulds made to make less than 1000 parts, but the amortisation cost was high. In some cases that high amortisation cost can be justified. The sums are simple if you know how many you can sell at what price, at what piece cost and what tooling cost.
The thin wall will make it very difficult to machine from bar stock.
Do you mean gouging during machining or during use as a bearing.
Regards
Pat
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RE: How would you make this simple part?
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From everything I've seen, if my idea can ever afford injection molding I'll be doing alright. For the foreseeable future, I need to look at alternatives.
>> For instance, that 0.5 mm seems dodgy to manufacture, using machining, for instance, due to low stifness of plastics (especially at a bit higher temps, as during machining).
Yes, I worried about that but those are my design constraints. Is there a stiffer material, like kydex, that retains strength/rigidity when thin?
To machine the part, I would route out the inner cavity from a thicker bar, and then thin it down and shape it from the outside. Does that seem reasonable?
>> Do you mean gouging during machining or during use as a bearing.
I meant that the material needs to be rigid and strong in the final product. The plastic is an encapsulation for some sensitive electronics. It needs to be aesthetically pleasing, and resistant to deformation. Since its thin, it also shouldn't gouge easily.
Hopefully that's enough information? Does anyone see how a vacuum thermoform, or press, or combination of the two might be employed?
Thanks!
RE: How would you make this simple part?
Cutting fluid will help to cool the part, but you will need to take the last few cuts VERY carefully to avoid the cutter picking up the plastic and tearing it.
In my opinion, the simplest way as already mentioned will be to use a two pot epoxy and cast the parts in a simple mould, most likely made of wood or aluminium.
You seem to be at a very elementary level here, comercially and technically in all regards. Are you a student. Is ths a homework project.
Regards
Pat
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RE: How would you make this simple part?
RE: How would you make this simple part?
RE: How would you make this simple part?
ornerynorsk,
Where on the planet are you? Last time I looked, hot runners were about £1000 per drop - cost price to buy in!. Your estimate of $5K for 16 cavity/sleeve ejection looks like the bargain of the century!
Let me know where this is - I have an application for an 8 cavity hot runnered job, ready to go apart from tool cost.
Cheers
Harry
RE: How would you make this simple part?
A simple single cavity mild steel tool with no cooling for the OPs part I would expect could be done for under A$1000.
Regards
Pat
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RE: How would you make this simple part?
Good Luck.
-b
RE: How would you make this simple part?
My proposal is to use thermoset material (phenolic CTI 175V or melamine CTI >300V) which can be compress moulded.
Such simple single mould inserts could be very cheap and installed in some existing mould.
Best regards
Boris
RE: How would you make this simple part?
from your comment, "I meant that the material needs to be rigid and strong in the final product. The plastic is an encapsulation for some sensitive electronics. It needs to be aesthetically pleasing, and resistant to deformation. Since its thin, it also shouldn't gouge easily."
If the wall is 0.5mm all the way to the top, you'll probably get a part that looks/feels like a drinking straw. But looking at the design now, it will deform and crack real easy. I suggest to increase wall thickness on the "closed section tip" (maybe to 1.5mm) and then on the open end, add a rib that goes round the open end. Sort of like, forgive my word, a condom.