Well just looking at the dimensions above which were for your molds… if you do it then you’re looking a few hundred dollars ($300-400 range), if you want me to do it then I have the charge for the time.
It isn’t very big versus car part molds.
a gallon tooling gelcoat.
2 gallons of polyester resin
strand mat.
each part will require a 2 part mold.
if you are also need prep before the mold, then add $100 for a gallon sandable primer.
Thanks for the chat, this looks promising.
No problem. If you have any questions let me know.
@brett_turnage . If I build a plastic master model, can you give me an estimate for the molds? The drawing may be enough to estimate. Is like to see what the cost is to have an expert do it. Huge time savings.
I’m determined to try this printed mold design but I’d love to see what you could save me in time.
Another option would be to print the parts as a mold with thick walls and no supports. Then model wooden ribs and Cnc the mold supports with our Crawlbot. That should keep the cost of the mold support block down. It’s a hybrid approach but would be a huge time saver. The print could even have tabs for screwing it down to plywood. Then you can swap out the plug when you have design changes or it wears out without creating all the 3D printed support structure.
@Brook_Drumm I would say it would be around $900-1000. It is two molds which are split, so a total of 4 separate mold sections that have to be made. So 4 days total. I haven’t been following the project much, but if you a mold you can easily make a carbon fiber plane with that mold, and I mean clear carbon finish. Would be pretty badass. I don’t know if that’s what you guys are planning, but if that is the idea then count me in!
I’d say 6 mold sections; 2 for fuselage, 2 for left wing and 2 for right wing. Plus horizontal stabilisers.
You could combine the Left and right wing as well as the stabilizers into one mold.
Carbon fiber sounds so awesome. Want!
But I’ll leave those decisions to andre. The original thought was a foam plane. Would the same mold do both? What would a carbon fiber plane cost once the molds are done?
People make large planes all the time out of fibre glass which I believe is cheaper than carbon fibre. So it’s not uncommon. We need to minimise the level of effort to succeed; I’m doing this purely on a volunteer basis. Without more contributors we have to keep things super simple.
I think we should make this decision later, no need to rush; keep both options open. We are still early on in the design phase and experimenting with large scale printing phase.
Fiberglass is cheaper only if you are doing hand laid. For a setup like this carbon vs fiberglass would be marginal. As for keeping the cost low, if you guys wanted something like that then we can figure some way of offering a fiberglass and a carbon plane which would be affordable. I’m happy to figure something out with you guys if you wanted to go the composite route.
To be honest, adding carbon in strategic areas and use primarily glass is the best use of materials. Unless you are planning to go 150mph/240kph, you don’t need all carbon. I have built race planes for 20+ years.
I would also advise to do a 3D printed plug and composite molds.
I build race cars. It does not need to be built in carbon, but it can be. If you have a nice mold you can make many different versions and perhaps some people may want a carbon version. i suggest it mainly for the fact that it can be. More of for fun, not necessity. Would be fun to see a clear carbon version.
Carbon is cool for sure. Didn’t mean to come off all knowing, just adding practical experience.
No worries, I took no offense. I understood where you were coming from. The fact that there are multiple composites guys who can give their opinion or thoughts on the topic is a good thing.
I love that we have some experienced pros adding info here. I think if we get some success here it will draw more interest.
@Troy_Peterson , what do you think is easier to design and fabricate, a molded foam model or a fibreglass model?
For sure a composite model is easier to fabricate on that scale. You would really need to know what you are doing to build large scale parts from foam and the tooling is the most critical piece of the puzzle. The molds alone would need to resist a tremendous amount of pressure so smaller molds are easier to build for that.
What kind of tooling? What if we were instead talking about half the current scale? Would PU foam construction become more feasible?
Update! Volume of fuselage and wing plugs for making molds: 0.1m^3. That’s 122kg or a cost of 3D printing these plugs for mold making: $2450, with above assumptions above and based on the volume from my CAD dwgs.
At my cost, the printed version is way cheaper. But I’m up for anything!