Composite Molding / Tooling Costs

Somewhat random topic:

It seems to me the major costs in the advancement of homebuilt aricraft, particularly composites is in the time spent creating moldless composite parts or everyone building their own molds. Essentially every part is some custom "one-off", making the time and costs to produce and eventually repair extremely expensive.

I was wondering if any group of homebuilders / homebuilt kit manufacturer has thought about building a set of molds that a group of people can pay to use per use or possibly to lower the costs more have investors pay for the costs of building the molds and over time they would make their money back (+ plus some profit to incentivize initial investment).

I know local motors has crowdsourced design and distributed micro factories to build custom projects where essentially the tooling, facility, and materials are crowdsourced or investor crowdsourced.

I imagine something similar could be done for the homebuilt market that would be attractive to outside investors.

For example: Let's assume Rutan's Skigull or some other homebuilt experimental begins to build a large demand base. The costs for certifying such an aircraft drive costs very high and with such small production runs as aircraft (think some of the largest runs for GA aircraft are < 100,000 units) are destined to it drives those aircraft out of reach for a majority of buyers and/or builders. To keep quality high and costs down composite molds are necessary for repeat-ability and "higher-speed" production but molds can be extremely expensive to produce. So get a group of investors (homebuilders) to pay for the tooling to build the molds upfront based on projected demand cycles. Then homebuilders could fly in to some facility, pay a fee to use the mold, which accounting for a time factor, would be MUCH cheaper than hand layup over foam core or building your own molds. Then the part could be crated up and shipped back to the homebuilder. The fee that is paid in would, over time, pay back the investors who paid for the mold.
As far as possible production damage to the mold is concerned I know in Europe some large molds for racing sailboats are insured against failure, so a similar market could exist.
r
This would greatly speed up production times for homebuilt aircraft and create a financial market for non-traditional investors as well. I believe this could be applicable outside of homebuilt GA as well to boats, bikes, cars, furniture, etc...

Just a random idea I had...does this already exist? Curious to hear the communities thoughts on it.

-J

If you could throw in an autoclave, then homebuilts could be made from prepreg composite.

However, I see a few sticking points from the manufacturing point of view...

The cost of making a mold is high. Sometimes very high. I was part of making a hydroform die for a small 12"x20" part. It was machined out of aluminum and the surface finished to 63Ra. Final cost to customer for a piece of aluminum that weighed just north of ten pounds was over $25k.

Molds for composite parts need to be nearly polished (who wants to look at a part with a surface finish like a jackfruit?) Polishing can be expensive on its own.

Factoring in the assumption that personal preference divides the market on an already small sector ( Bob will want to build the SuperBrickII and Jim will want to build the SkyPig, both composite construction) and I just dont see enough volume to return tue investment.

Furthermore, it would seem logical that if there was sufficient volume, then the investor could have a higher RoI if they produced the parts...ala Glasair.

Just my thoughts. However, I like your thinking.

It would be just awesome if there were a shop with a couple Bridgeport Mills and some engine lathes and various other tooling like a rubber box press of decent size where an aspiring homebuilder could make parts by renting out the shop for a few hours or a weekend. Then tote them back to the home base and assemble them.

Sent from my XT1585 using Tapatalk

I agree SOME mold costs can be astronomical. I do not think we are talking about those kinds of molds at this point- at least I wouldn't think so. I am thinking of just composite molds at the moment. Something you can get 10-20 runs off of before failure or major refurbishing. I'm looking more at the composite high end boat community as a model where a lot of low production runs are produced off composite molds.

Even if the mold(s) that cost 20k 10 runs at 2k each, or whatever multiple, still breaks even for a group of builders and accomplishes the main goals of high production quality, repeatability, and faster- hence cheaper build times.

The reason son for not commercializing the builds of the molds and components is to remove a much of the certification and liability factors, again, in the hopes of keeping production speeds high and costs low.

Still interested in hearing criticisms and/or further expansion of the idea...