The Road to the Spectral LAM's Kickstarter
Disclaimer – We are not experts on 3D CAD printing. What is being describing is what we understand from our printing partner and the limited experience that we have with the printing process – so if someone out there has better info, we welcome correction.
Spectral LAM's Kickstarter Link
3D CAD is not a cheaper way to sculpt mechs. Using the free drawings from Steve Huda, we spent over $2,000 to have the Waneta ground mode printed. Multiply that by nine and $18,000 of the $25,000 goal goes to produce the masters. Our hope was to get about 300 backers at the $185 level. If we accomplish that, $60 of their pledge goes for the 3D printing and $125 goes for 9 mechs and shipping. That’s how we priced the $185 level. We are hoping that the next few print jobs will cost less but we are not confident that will be the case.
- Here is what it takes to convert a CAD drawing to a castable master:
- - A CAD drawing has to be exploded into castable parts. This involved Stu going to spend a day at the CAD printer’s place, working with their CAD operator to identify the places to split the drawing and then making sure that each part has a socket or other joint to ease assembly.
- -A CAD drawing is not a solid, it is a frame with skins. This means that when you print it, there are hollow spaces that would tear out a mold and render the parts uncastable. So the CAD operator at the printer also had to take the exploded parts and fill in the hollow spaces.
- - Finally, some parts on a CAD drawing are too thin to cast, so the CAD operator at the printer had to thicken some of the parts while still making sure that they would fit.
- - There is a cost for the CAD time required to take a beautiful 3D drawing and render it into a producible solid master
- 3D CAD printing is available in a range of finish qualities. Essentially a CAD printer prints a solid model by building up layers. The thinner the layers, the smoother the surface. Machines that print in very thin layers are more expensive than machines that print in coarse layers. And the thinner the layers, the longer it takes to print. Printing cost is driven by machine time and the cost of the machine doing the printing. We are using a high end printer to get a surface finish and level of detail that we consider necessary. And that is expensive.
- - Even with this, the surface finish has slight flaws that, while acceptable, are annoying. Paint will cover them up, but the surfaces look like the metal was welded and then ground smooth with a grinder. There are what look like buffing scratches in the surface of the metal.
- - This is acceptable because a CAD drawing gives crisper detail, sharper edges and a level of symmetry that is better than what we can do with hand sculpting. It’s not obvious at first, but the Waneta looks more like a machine than almost anything we have produced. So the tradeoff is worth it.
- - If you look at the resin dropships (which were printed several years ago), the stairstepping between the layers is noticeable, but acceptable in those models which are large with limited detail. Our customers wouldn’t accept a mech with that kind of surface finish, and frankly, we wouldn’t sell CAD sculpted mechs with a surface finish like that. We have had 3D printed mechs submitted to us within the past year that were unacceptable because of the low quality print jobs. We’d love to be able to do this on a $2,000 Makerbot, but anyone who thinks that a Makerbot prints at an acceptable level of quality should just build their mechs out of Legos
- - Even using a high quality, fine grained printer, we still had to send the printed masters out to a sculptor to clean up and thicken a few parts.
- We have no doubt that we could have done this cheaper with a Chinese company. But there are trade-offs to going that way that are unacceptable to us (Mike and Marc).
- - Most importantly, the printer we work with is 30 minutes from Iron Wind. This means that we can send Stu there to show them how mechs are manufactured and how customers assemble them. That may seem insignificant but it is very big. A bad fit at a leg or arm joint is the difference between a mech that is easy to assemble and one that takes hours to modify and assemble. A poorly exploded part can be uncastable because it has undercuts. Those nuances are not obvious to someone who has never manufactured pewter in black rubber. Stu spent most of one day, standing behind the CAD operator, helping him to understand what the parts needed to look like so that we could cast them and customers could assemble them. We expect that he will have to do that (to a lesser degree) for each of the nine models.
- - Having our printer up the road means that we communicate in the same language – no small thing (see bullet point above)
- - It also means that we know what we are getting and that we know when we will get it.
At the end of the day, our goal is to make the best mechs possible, at a price that lets our employees earn a decent living. We think that 3D CAD printing has possibilities and the purpose of this Kickstarter is to get some seed money to learn if the process is economical at the quality levels we demand.
