'Assisted Scratch' from plans?

Let's say a guy ordered a RV-9A plans/manual CD and printed the plans 1:1 from the PDFs with the intention to scratch build most of the plane. Is building from the CD plans/manual allowed by Vans?

Let's also say that the guy found 10% of the parts too much trouble to fabricate himself. Would Vans sell him those parts outside of a kit (a la carte)?

Sort of an 'assisted scratch' approach.

Welcome to VAF!

Dave, welcome to VAF

As for your questions----------a number of Vans employees are on this thread, I suspect you may get an answer from them.

Or, you could just call the factory and ask.

Sounds like you have a rather ambitious project ahead.

Somewhat ambitions... I am a computer/electronics nut besides being a pilot and am about 60% of the way finished with a 4'x8' CNC router table that would make the cutting/shaping of pieces and forms a whole lot faster than the traditional scratch method using snips.

What I am wanting to do is fabricate all of the 'flat' pieces myself and buy the more complicated bits from VANs.

I am not building an RV-9 and don't have a set of those plans, but I seriously doubt that they provide anything like enough information to scratch-build the plane.

Basic things like the lengths of parts and the thicknesses of the materials isn't shown on the RV-7 or -8 plans, because the kit comes with those parts. You might be able to get sort of close, but I really doubt it. Since the kit is pre-punched, hole spacing probably isn't in the plans.

I'm building an RV-3B and that's plenty challenging enough. It has per-made parts and actual plans that are almost enough to scratch-build it and it's still a real project.

Dave

Sadly, if the 9 plans are like the 7, then they are completely inadequate to be used to scratch build an airplane. Dimensions, angles etc are needed to make the parts. Definition of materials and thicknesses are also incomplete. The plans, as provided, serve very well to assemble an airplane, and with sufficient dimensions to fabricate a few of the parts. It is my understanding that plans exist for the RV6 to do what you are wanting.

Is there some reason you don't just get the kit and then make any of the fabricated parts needed by your proposed processes? You would get a proven design and a taste of manufacturing.

make any of the fabricated parts needed

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Can you add some detail to that? Not being a Vans builder (yet) I am not familiar with how (in)complete the kits are.

It is my understanding that plans exist for the RV6 to do what you are wanting.

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From Vans? or from folks who bought a set and never used them?

As noted by others, the plans are not adequate for making most of the parts. They show the shape and layout but not dimensions, thickness, etc. For example... look at the plans on CD. Pick any outer skin at random. Now figure out how you'd cut it to size, let alone plot the hole locations for CNC punching or drilling.

If I were designing an airplane to scratch build, the Van's plan drawings would be extremely helpful to see how it's done well. And of course they are pretty good for assembling one of their kits. That, however, is about as far as it goes. As for them selling you parts, I don't know. I've heard mixed reports from non-RV builders trying to buy parts.

As for CNC fabricating the parts Van's doesn't supply pre-made... there are some that you make yourself, often from angle stock. Cut, trim, drill. I suppose you could CNC them, but I have a CNC router and I have yet to see a part I couldn't make several times over in the time it would take to draw it up in CAD, generate a toolpath, and ruin one or two on the CNC machine until I got it right. The band saw and rill press aren't nearly as precise but they're a lot faster.

Dale, point well taken... I had planned to CNC only the sheet stock and maybe some of the formers, not the 'solid' parts.

RV-3, 4, 6 plans

I think you get many more 'specs' on the old hand drawn plans. The newer plans are basically an assembly diagram vs the old ones which gave many dimensions, which would work for your purposes provided legal hurdles are dealt with.

I built my RV-6A without any kits from Vans. I used leftovers, crash parts, abandoned parts, etc and a lot of creativity. There was an article on it in Vans newsletters years ago. It was a ton of work.

davecove said:

Dale, point well taken... I had planned to CNC only the sheet stock and maybe some of the formers, not the 'solid' parts.

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Yeah, those (sheet stock, bulkheads, ribs) are exactly the ones that would prove most difficult given the available (lack of) data.

Ok, after reading this thread, 'she who must be obeyed' gave enthusiastic permission for the RV-9A study plans CD now and the RV-9A empennage kit in October with the other kits to follow as I complete them.

Frankly she is glad to see me abandon the RV-9A scratch build idea...

Whoopee for me!!

Dave

Congrats on getting the OK from "she who must be obeyed" Not a lot of parts that a CNC machine will help with. Most of the sheet aluminum parts are formed. Probably the best course of action would be to order the empennage kit and have them omit the parts you can fabricate yourself, like the HS and VS spar doublers. They will credit you for 75% of the cost of the parts omitted from the price of each sub kit.
Your CNC machine will help you with the parts which you must fabricate yourself from stock. [included in the kit]

Vans does sell individual parts, at least to registered builders. In other words anyone who has ordered at least the empennage kit and has a builder's number.

chaskuss said:

Probably the best course of action would be to order the empennage kit and have them omit the parts you can fabricate yourself, like the HS and VS spar doublers.

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If you do decide to do something like this------please purchase the correct type/grade/size of material for the items you omitted.

All alum angle stock (as an example) is not created equal.................ditto other items too.

Same goes for hardware like nuts/bolts/screws.

If you want to scratch build a 2 seater side by side from Vans - Buy the RV6 drawings from someone and get there builders number ... The RV6 drawings was done for scratch building .. i.e. you have all the info you need ... (and a few errors thrown in for good measure ...) Then make sure you have plenty of time and really enjoy metal work !! After the 6 - it was all kit build .. Hence drawings are for 'assembly' only .. not 'building' from first principle .. Which is why they have been so successful .. as the kits are well made and great value .. and most people want to fly .. not bashing metal

In the old days there were folks who thought they could save money by scratch building an RV-6. Back then, because of his volume, Van's could fabricate the parts cheaper than an individual could buy just the raw material. It's probably a wider cost gap now. I've done 2 RV-6 slow builds and you'd have to be a masochist to scratch build one.

Congratulations

davecove said:

Ok, after reading this thread, 'she who must be obeyed' gave enthusiastic permission for the RV-9A study plans CD now and the RV-9A empennage kit in October with the other kits to follow as I complete them.

Frankly she is glad to see me abandon the RV-9A scratch build idea...

Whoopee for me!!

Dave

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Congratulations Dave.
Better part of valor I'd say.
So much help here you'll be done in shorter time frame with a slow build 9a.