Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by Victor Bravo, Feb 19, 2019.
This is the current price for that engine.
It's typical "stick and ply" construction. You cleco the 3/4" x 3/4" (20x20) sticks (longerons, seat rails, etc.) to the side skins, then cleco on the top and bottom skins through the same sticks.
The little red dots show where the top and bottom skins would cleco to the sticks. ...I didn't draw the holes for the top and bottom skins because I got really tired of drawing a gejillion little holes. And like I mentioned a few posts ago, unless your going to CNC two faces of the sticks there's no reason to add the holes at all. I used the cleco holes for the splice in the skins but I'm just going to go "old school" on the sticks (table saw, clamps and AC nails).
The Verner has mounting holes on flanges in the case. The mounting flanges are coplanar with the primary back surface plane of the case. But behind that plane is an air mixer/distribution chamber to which the intake tubes are mounted and run out to the cylinder heads. And then behind that the carburetor. The carb in theory could be moved and run via a hose to the mixer, but that mixer chamber is definitely part of the case and you'd have to live with that there.
That said, a few standoffs with bushings is all you'd need to hang the engine off a firewall so designed for it. Otherwise a basic engine mount is probably called for.
You can bet that if I were to build something like the ranger it'd get the 3V. But I don't know if, as designed, it would be drop-in. But I see no reason a proper mounting solution can't be figured out with minor tweaks to the design.
I can send you a model if you'd like to toy with the idea.
Para-zoom in Germany sells a small block V-twin 33hp engine with integral redrive, ready to run. The Verner 3V will be very much worthwhile if all it takes is a few standoff bushings.
I would absolutely welcome a model of the engine! That would be a huge deal in figuring out how to mount it on a Ranger.
The original idea was to use a Parazoom and all options are still on the table. ...but a wide engine like a 1/2 VW or a 3VW on a skinny airplane would just look right. Of course there's the danger of Erkki burning his feet on the lower cylinders.
Go for electric.. Especially twin engine - it will go with air cooling alone.
Mayby not as sweet on power/energy as rotax 912, but better than 4 stroke conversions.
Any hope on model with negative stagger ranger rendering ?
At some point you have to "lash the helm" or you'll never get where your going.
Ok, that makes sense. It's what I planned to do anyway. The 20x20 is on its way, and I'm eagerly awaiting the arrival of both the Ender3 printer and the Lowrider. Getting impatient... any chance of the gusset files? Prepping the cut paths on them is at least something to do while I wait...
Oh - and if you have the DXF files for the FritzTable that would be excellent!
The gussets (the whole front end) will change depending on the engine. If your going with the V-twin all the original stuff will work, I just need to save out the DXF's. I'll let you make the cookie sheets, you can fit the gussets into the scrap on the current cookie sheets.
Can you measure the mounting holes on your V-Twin so we can make sure they're the same as the ParaZoom? ...I think all those Vtwins are pretty standard.
I'm up to my eyeballs in routing out a VP-2 wing the next few days. An out of town friend is helping (they're his wings) so I can't put it on hold. But I'll make the table DXF's as soon as were done.
Do you have SolidWorks eViewer? (free download) I could just "Pack-and-Go" all these models to you and you could mess with them all you want.
Yes, I do have the eViewer. Thanks. I'll be going with the v-twin, and I'll measure the mounting holes this evening. Looking forward to the DXF's I'll post the gussets on the groups.io site if you like - I'll squeeze them into the existing cookie sheet if they'll fit.
Do we have any news here regarding the geodetic tailcone, and eventual attachments for the tailsurfaces?
I just have to clean up my table so I cut side two (I just pulled a 3 day VP-2 CNC marathon) . The tail surface attachment is standard VP-4 style
Oh please, do tell!
Found this thread over the weekend, have read it and any associated threads I could find. Looks great, I'm looking forward to starting soon, though my build will hafta be the ole fashun way... kuz i aint got no Sea & see ruter...
Mike(y) in OR
If this going to be CNC cut, what about box jointing the ply? Something CNC can breeze through, but would take a long time by hand...
There's no need to cut anything with CNC routers. None of the pieces are that difficule, and there are a lot of straight lines. I don't think you'll have any problem at all.
OK, before I rush off to google box joints - can you elaborate?
[2 mins later]
Well that didn't take very long to google. OK, I'm familiar with this sort of joint.
Hey Fritz - that's actually a good idea...
Some time ago I acquired a set of lock mitre bits for my router. I never used them, but thought they'd come in handy. Now it strikes me that this might be a great way to mate the sides of the Ranger.
Finger joints (aka box joints), locking rabbet joints , dovetail joints, etc would look interesting. But they all work better in thicker stock than this ply. Glued corner sticks will provide more strength ( due to the glue area, which is the important thing here), and will be much quicker and more forgiving during assembly.
I've just checked my locking mitre bits. I have three of them, and the middle-sized one is for 19mm - 25mm wood. Should work swell on my 20mm spruce doublers. Might give it a go and see how well it works. I've been keen to give the bit a try anyway. Plenty of 20mm scrap in the shop...
Finger/box/dove tail joints won't add any strength to an edge joint on thin ply. They really wouldn't buy you anything over the cleco method but you'd be giving up a whole lot of benefit. Actually they wouldn't buy you anything at all. It would easier to glue the fuselage together without them
The clecos 'locate' the sticks in their exact position on the ply and holds them there, they even provide clamping pressure for the joint. Then they locate the mating skin the same way.
Finger joints would give you an edge to align to in one direction but not the other and they wouldn't hold anything in place. You'd have to hold the stick in place manually while you clamped it and/or nailed it. Sticks like to slide around in wet glue. Keeping them in place until you get them secured takes a lot of attention.
Finger joints on the internal parts like bulkheads would needs slots cut in the side skins which would need some sort of corner block on the opposite side from the bulkhead.
I'm a big fan of fancy CNC joints but they just don't make sense in this application.
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