exxos's Atari, Amiga & retro forum

So I de-moulded this morning to a bit of a surprise:


You can see 2 items, the 'plug' formed in the point where I poured the resin in, and a lens like item that is about 1/6th of a mouse ball!! The bit that did form is really nice quality, so it's a lesson learned and actually quite encouraging.

Ok, so the thing to learn from this is that the mould obviously formed an air pocket in the sprue channel as I was pouring. What is weird is that it seemed like a lot more than just this small amount went in.

So, will I try again? Of course :) I just need to refine my technique for getting the resin into the mould without forming an air pocket, and I'm thinking rather than pouring, I should inject it in using a syringe.

I could also easily create a vent near the top, so the air pocket can never form. This will mean that there will be another sprue, but since I have to deal with one already, then it isn't an issue.

Onwards and upwards.

Failure teaches success...

HigashiJun wrote: 24 Mar 2023 10:00 Failure teaches success...

Indeed it does. Nice quality of moulding though.

rubber_jonnie wrote: 24 Mar 2023 10:02

HigashiJun wrote: 24 Mar 2023 10:00 Failure teaches success...

Indeed it does. Nice quality of moulding though.

Yes, as I can see on your picture.

Do you think the resin would resist to frictions without wearing in few months ?

HigashiJun wrote: 24 Mar 2023 10:09

rubber_jonnie wrote: 24 Mar 2023 10:02

Indeed it does. Nice quality of moulding though.

Yes, as I can see on your picture.

Do you think the resin would resist to frictions without wearing in few months ?

From the resin I had left, it has gone really pretty hard, and since it isn't going to be used daily, I expect it to last reasonably well. The original was made of epoxy anyway from what I can see, so It can't be much worse.

I may also try using a thicker resin, more like the opaque Araldite types, to see if it gives a different result as it may be harder wearing.

rubber_jonnie wrote: 24 Mar 2023 10:29 I may also try using a thicker resin, more like the opaque Araldite types, to see if it gives a different result as it may be harder wearing.

Yes, it's worth trying.

rubber_jonnie wrote: 24 Mar 2023 09:39 You can see 2 items, the 'plug' formed in the point where I poured the resin in, and a lens like item that is about 1/6th of a mouse ball!!

No problem -- just only move the mouse a couple of mm in each direction and whack up the acceleration, yeah..?

:mrgreen:

BW

Badwolf wrote: 24 Mar 2023 10:37

rubber_jonnie wrote: 24 Mar 2023 09:39 You can see 2 items, the 'plug' formed in the point where I poured the resin in, and a lens like item that is about 1/6th of a mouse ball!!

No problem -- just only move the mouse a couple of mm in each direction and whack up the acceleration, yeah..?

:mrgreen:

BW

I could use the 'ball' as a lens now, so have accidentally discovered lens making in the process, surely the lens would magnify the sensor signals and provide adequate acceleration?

:lol: :lol: :lol:

So, I just found this on eBay:


So have ordered one to see if it is a feasible option too.

Out of curiosity... how do you intend to remove the cast marks after it has been made?

I am not sure it is achievable without some sort of mechanical ball sanding machine?

Molds like these tend to leave either a line around the circumference or a burr at the point the liquid is poured in.