I might be completely on the wrong track, but if anybody please direct me as I am new to this. All sewerage manholes in this part of the world, needs to have an extra sealing plate below the metal cover.
Attached find a photo example of one. Basically they required 25% glass, 75% polyester and 1.5 mm Vinyl Ester layer. Also a rubber seal around. GRP thickness 7mm, diameter 500 mm.
We needed to be able to produce 20 000 per year. It was impossible to do the quantities by hand lay-up. We imported a Vacuum Infusion Machine. In short, the heat generated in the castings created extreme bubbling and weaken the product that we ended losing 60%. We have now completely stopped trying.
I have been walking around with 3D printing possibility in my mind for some months now, but have no expert to go to in this field. We can even change the materials as long as we comply with the specs. Any composite can be considered.
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MB3D
2
So are those made out of a blend (mostly Polyester) that also contains glass particles or is this a part of Polyester on which you lay a piece of glass?
Colorfabb is a famous company that produces Polyester filaments for 3d printing, they also have a version that includes 20% carbon fibres, maybe they could advise you further if exotic plastic blends are required.
e3d sells a filament that contains glass particles, however the main plastic material isn’t Polyester but Polyamid (Nylon).
Maybe for quantities of 20.000 you should produce the part with injection molding ?
I hope this helps a bit.
Cheers,
Marius Breuer
Hey Manie,
if I understand you correctly your original plan called for a dry glass layup, polyester resin infused panel. Bubbling during infusion would indicate to me either a reaction within the resin, a reaction between the resin and the bagging material or leaks within the vacuum bag. Have you considered trying different resins like epoxies? Or even prepregs to remove the need for infusion?
The laminating details aside, I believe it will be quite tricky to achieve a satisfying result with 3D printing in this case. It is notoriously difficult to predict the exact strength of a printed part, let alone one of this size. So a considerable amount of time will need to be spent on material testing to ensure the part fulfills its requirements.
Additionally since your volume is quite high, quality control will also be tricky. While visual, non-destructive quality control is possible with filaments like taulman’s t-glase lineup, it would not be possible with composite filaments, since they are opaque.
On top of all this, I would estimate the production time of each printed panel to be about the same of an infused panel, so however many employees you have now in your laminating crew, this is the number of printers you could require.
These are just my thoughts on your plans.
Sincerely,
Jonas
Hi Manie
the parts you want to produce are quite large and need to be manufactured in relatively large quantities.
3d printers are really not suitable for this. You will be much better off producing these using injection moulding.
regards
mark
Thank you Mark. I thought it will be, but injection moulding just don’t work. The chemical reaction is causing extreme the bubbles. The polyester resin for injection moulding needs to be fairly liquid, therefore needs more catalyst. This increase the Heat.
Hi Manie
Do you have the specs for the parts?
Thank you Jonas. You are correct in the sense of the reaction. To do infusion with bagging works fine, as the heat if the resin can escape via the the bag. Vacuum infusion in a closed mould, the heat is simply to high. is just simply to high.
What you said regarding epoxies, is what I would like to try and learn more about. In the boating industry we use it only in crutial areas, or in repairs. The reason is that it"s costly. We need to sell below $20 a part.
Labour is not costly here, but the quality is raw. Inspections make thing also more expensive.
Best
Manie
Hi Marius, thanks for your input.
Polyester in liquid form main ingredient. Glass is thin strains in different forms. You can see some here Buy Fiberglass Glass Online - In Stock & Ready to Ship | Fibre Glast . The acts the same as metal bars in re-enforced concrete. The glass is the strength and the resin the glue.
I will definitely follow up on Colorfabb, sounds interesting.
The nylon idea has been considering. I do not know enough about it. I have seen a YouTube where they were using nylon with continuous glass thread. I have sent mails, no response yet.
Best
Manie
MB3D
10
Ever checked out the Mark 1 ? (i think that’s how the printer is called) it’s a relatively big printer and it prints in nylon. The main advantage of the printer is that it can lay in a variety of continous fibres into the prints, possible are kevlar, carbon, glassfibres and one fibre i forgot the name of.
