J-4 project-3.14159265359

Drats,

Looking at the nose rib tools I had started to notice something not looking right last night. Turns out the tool path on the full rib was set wrong resulting in wall art.


I started to notice the error during cleanup last night but that was not the time to figure the issue out. The tool path can be selected for inside or outside a line and with a 1/4 cutting bit this makes quite a difference.
At this time the router setup and operations are hosted by a new member of the EAA chapter I run, I am in training for this tool such that I am not "set free" yet. I might have caught this error had I sat down and reviewed the cut path before we hit the start button.
Oh well, I sure prefer scrapping parts that all the time was in the drawing and not in the cutting and finishing of tooling as was done in years past. I do hope there is some room on the 4X8 sheet of OSB to fit new parts once the tailfeathers are ready to cut.

Here is the Handley & Page LE slat in place, well at least the paper doll concept of one.

And two pics of the slat design.

I want to than Brian of Steve's aircraft for spending allot of time with me describing details of how these slats are implemented in the Helio Courier.



I will shoot more pics when the light condition is more favorable.
With the slat in the deployed position you can see a pen line depicting where the LE of the wing will be.

For a slat system I do like what I am seeing here.

Can see allot better when the sun is not blinding through the window as it reflects off the snow.
Clean wing shape.


All down,


And a clearer shot of the slat retracted,


And out,

Last night we cut out the tool to build the elevators and rudder on. These are cut into 1" MDF as the other parts have been. Unfortunately one section turned out bad, these were a complex drawing with 3 separate drawings overlaid and combined. The cuts in the material were done in 3 different depths, shallow around the perimeter for the trailing edges, these routed well. There were a few through holes such as where the control horns will be. There a central groove where the 7/8 spar tube for each will be. This drawing had two open spots from the hours of editing when producing the drawing, we found them easy enough but there was one .032 overlap in the 73" tall drawing. The issue with this was the toolpath reverted to cut outside the lines which is easy to detect and indicates a drawing error, but went undetected before sending to the router. I am glad I was vacuuming up the swarth as the cut was proceeding and noticed the nearly 1½wide path for the 7/8 tube such this did not totally trash the tool. I took the time and found the tiny overlap and this time inspected the toolpath myself to make sure it was right. Other than needing shims to locate the spar in each part which might actually make the removal of the weldments easier, that could be a plus.

Pictures and more later, the MDF is still on the rack on my truck in the garage since it was still snowing here on my drive home and now raining this morning. Dang that thick MDF is heavy.

Here are a few pics on the router,


Finished cut in my storage building

Following this build very cool.

A few fresh screenshots with the slats installed and in the down position. I like them. I do have some clearance issues to work out near the lift strut area of the front spar since this it where the mixer is for the drooping ailerons. Everything will fit together fine but changes do need to be made. These images are with the outer wing extensions in place.

Cub junkie said:

Hope I don't drift your thread too much. My dad leased a Helio from 1967 to 1970. Our strip in Kansas was 60 miles from the factory in Pittsburg,KS. On our first demo the factory test pilot, Larry Montgomery filled up the airplane on our ramp and took off across the runway. He tossed the airplane into about a 75 degree left bank while climbing and those left slats made a very distinct pop as they extended abruptly. As he rolled out they started slowly retracting. That was my view as an 11 year old sitting in the porthole seat. Amazing aircraft. My dad used it to replace a Hughes 269.

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I may have met up with you or your folks way back then, met quite a few. I was working with John Roberts..... Helio Distributor out of Spartanburg/Cross Anchor SC. We made trips back and forth to Pittsburg KS when he was trying to get Helio going again back in the late 70s early 80s. I flew with Larry some, never did get the full checkout. Larry actually lived about a half mile from me. I used to cover Helio ailerons for him. Ended up leasing John Roberts' airport for several years after he died.

Over the past month I have been doing more drawing and calculating, the main subject has been LE slats. I am going with them, the Handly Page style that is. Most recently I have been working out if the slats will be supported on formed tubing as the Helio is or whether I will machine the supports. At this time I think I will use machined supports. Being I need 12 supports in all it is more effective to just draw the parts, basically done at this time, then just lump a hunk of aluminum on the mill and let it make them.
Much less time for me than running stainless tube through the rollers to hit the 22¼" arc, mill the holes for fasteners. weld in the bushes and ream them.
The aluminum billet parts will be an I beam in cross section with varying thickness of the flanges as needed where the peak loads will be.
Metal chips might fly in later May to make the "kit"

Charlie

I am building up something similar........... when it came to rolling the radius or arc in the slat track I use a fairly inexpensive roller to do it, works great. I have 2 different tracks I'm working with one is just over 30" and one is around 26". I just did pi x D, cut the tube to that length and rolled till the ends touched.

If I went with tubular supports it is looking like either 1" or 1.125" 304 stainless tube. I am leaning toward the 1.125 tube which I do not have rollers for. I do have bending dies since that has been a common tube used in the oil system of Porsche 911 cars I have built for decades. The tube bender does me no good here.

These guide tubes are right about 18" long with two fasteners in plane at the front to attach to the slat and a flattened area to sandwich the rod end attaching to the bellcrank at the aft end. I would also need to add a stop onto the rear to limit forward travel.

To me I would need to make changes to my medium tube roller, make a set of rollers for the 1.125 tube and being I would be best to roll at least 6' lengths of tube this can not be done in my lathe as I have worked medium tube since the lathe is against a wall.

I compare this to lumping a ¾" X 10 X 36" 6061 plate in the mill and let the chips fly. Yes there is some second session machining to be done but nothing difficult.

Material cost, pretty close to equal.

Secondary parts, the guide rollers these ride in would be either curved face or flat wheels, neither an issue for me.

To me time involved is the issue, If I had an employee at this time I might go with the tube but I think the billet is they way since 90% of the drawing is done and that is the major part of my time for those parts.
Yes drawing the round tube parts ate less of my time but I would still need to draw and build the tools to make each part and each part is over an hour to build. I need 12 of them.

Humm, late April since posted here last, dang summer slid on by. I am spending a stupid amount of time putting together our September B-17 tour weekend. That is coming up soon and eating many hours a day.
On this plane, I did not travel out to OSH this summer, I had intended to spend the week making parts for this plane but instead spent way to many hours drawing a plane that I have wanted to build for nearly 30 years. The concept just finalized in my mind and needed to be drawn. that one is an all composite bird, reliably small and efficient and now with a wide speed ratio. It will be a 550# 2 seat bird with a Yamaha sled motor providing 150ish HP. It should scoot.
On this project,
Allot of detail drawing has been done but not much welding or chip producing recently.
Since recent posts have been about the LE slats some decisions and work on them has been done.
These are the lever arms that will insure that each slat will travel evenly.


These are fresh off the machine from their first pass of being made. A fair bit of work to do on them still. Heck not even washed up yet.
The arms the slats will travel on will be machined from Aluminum as well, not formed tubes. They are a slender 18" long machined part with a mild curve such that the slats will travel as needed. The drawings are ready, well at least one part drawn in 3D but needs to be placed in an array so 12 can be cut in a session. I still need to finalize the drawing for the jig they will be machined on so there will be a one time setup and the parts can be flipped to cut the backside. The holdup is getting a proper tool path in Fusion 360 which is a new to me program. Steep learning curve for me.

The need for 12 of each part is that the wings will be built such as the plane can be flown with either a short, or call it a Mid length wing as well as with a 4' extension easily added on each wing. So call it a 30' short wing span and a 38' long wing version.
With this the main wing will have two sections of slats on each side that do not extend all the way to the root. This is a balance between the desire for ultimate low speed lift and utilizing the slats for safety.
With the extended wing swapped on there will be 4 sections of drooping aileron.

Wow. I'm working over the details of milling a simple bell-crank. Those lever arms are an order of magnitude away from what I can imagine, at least for now.

Question: do you use some kind of plastic material for the interface between the grooves and whatever is guiding the slats? I'm wondering what to do about aluminum to aluminum sliding contact points.

Here is a rendering of the arm the slats will travel on.


The left end is where the slat will attach with two ¼" fasteners, only one hole shown here. This arm will ride on rollers, two each top and bottom.
At the right end where the through hole is shown, the part will be milled out for a rod end bearing which has a rod that connects to the tip of the arms I just milled.
The curved lip on the right upper end is the full extension stop.
The rollers themselves will be machined from Delrin, flanged sides to guide with sealed bearings inserted.
All aspects of this "Ibeam" have varying thickness as needed to cope with the loads involved.

FWIW these parts are being cut on an older Gerber 408 router. The guy that owns it was impressed when he cut a few small .080 aluminum shapes.
He was stunned when I filled the room with chips doing a complex job he could not imagine his machine could do. would hate to try to make these on my manual machines.

Here is a rendering of a Slat Rib. These will be machined in aluminum and then bonded into the carbon fiber skins.
I will make 14 of these, just need 12 but never know when one will make scrap. These will take two bolts up from the bottom retaining them onto the curved arms.

And here are renderings of the slat pieces together.

I had a chance to do a little bit more on this project. After allot of redesign work over the past few months I have started building the spars for the vertical fin and rudder. These are considerably different than one would find on any plane that utilizes a wire braced tail for a variety of reasons. Being the tail end of the plane is tucked over in a corner where the bicycles hang in storage I can not say these are photogenic shots.
The bottom of the spar is built onto a plate that will be embedded into the longerons and carry the lower rudder hinge.

I should add this pic as well since it shows the lower plate being taper milled out to reduce weight a bit yet distribute loads well. The longerons as with the lower section of the spar have an .065 wall tube as a doubler over them to spread loads further.
As you see there are no mounting provision on this plate for a leaf spring but the provision for the front spring bolt will be there. Easy enough to add the rear mounting for the spring should the coil spring setup not be optimal.

Thanks for the update. That looks intriguing. A few questions:

I couldn't really tell, but is your tail not going to be wire-braced?

How thick is that plate on the bottom? I'm guessing .090?

And, on the vertical spar, how did you decide on the spacing and location of the crossmembers? (I was thinking about the widest separation point having no cross-support--I don't know if it's necessary or not, but it looked different to me).

BTW, your welds look very nice.

RVBottomly said:

Thanks for the update. That looks intriguing. A few questions:

I couldn't really tell, but is your tail not going to be wire-braced?

How thick is that plate on the bottom? I'm guessing .090?

And, on the vertical spar, how did you decide on the spacing and location of the crossmembers? (I was thinking about the widest separation point having no cross-support--I don't know if it's necessary or not, but it looked different to me).

BTW, your welds look very nice.

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The horizontal will be strut braced using some Carlson extrusions.
The vertical will all be tube structure, no external braces. These tubes are 3/4-.035, pretty stout for the loads involved. Being the Vfin is an airfoil shape, this allowing me more room for structure such that I can get the torsional stiffness I desire.
The bottom plate is .125 and milled at a taper down to 0.040 web at the front-most portion leaving the full thickness along the edges for welding into the longerons, there is a 3.7° bend under the vertical spar so the plate lines up with the longerons.
Crosstubes, the second tube up is placed where two forward diagonals attach, the topmost is essentially mid span of the tubes and not critical unless I had chosen to utilize .028 wall material. It is a short way below the upper hinge attach point which is a bolted on machined part.
the lowermost cross tube is a bit below the swing of the elevator bellcrank.

At the widest point there will be substantial structure added going forwards to hold the pivot tube for the horizontal spar with a 3/8 pin aft of that for the elevator bearings to ride on.
The rudder will pivot on 3 ball bearings, the elevators have 2 on each side.

Was thinking about this project earlier.... Any new updates..??

Brian.

Hi guys, finally some work being done here. Last 3 months of '18 I was working out of state, where of all damn things I aggravated a 20 YO neck injury. So I had to wait out six week where I could not hold my head up very long each day. Getting stronger now but not great, yet.
But beginning of February I got back in the shop and have been semi productive again.
First I will follow up a question RV has on the vertical spar and the lack of cross tube at the wide point. That is now built after may variations of design.
This structure carries the inner mounting of the elevator and horizontal. Here with the initial structure and then with the elevator bellcrank and cross tube the horizontal will mount in.


Here is this structure welded to the lower tubes with a main bracing to the spar.


And a more distant view with the horizontal rear spar set in place.

i was worried about you.:lol:

tempdoug said:

i was worried about you.:lol:

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Thank you Doug, It is life on the roller coaster but I selected the one that gets stuck in the mud at times.

Happy to see you back at it... [emoji3]


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still thinking 0-200 for a motor?

Steve's Aircraft (Brian) said:

Happy to see you back at it... [emoji3]

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It feels good to be back at it. Allot of progress with allot of detail changes as well.

I desire more power than the O-200, Design creep with the flaps is leading me away from the light and simple.
I have a core O-290 here which I will complete a mount for before the Fuse is off the work table.
If I can get my hands on a loner engine case for a Dynafocal mount I would like to get that built now as well. I might be able to make that mount without a case but the chance of error is high as well.
But my mind is wanting more power and I may go something more controversial as well.

CharlieN said:

View attachment 41551 View attachment 41552

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That is an interesting hinge support for the elevators. Do you have a ball or roller bearing in the elevator tube? Seems that this would be a good location for some friction reduction.

skywagon8a said:

That is an interesting hinge support for the elevators. Do you have a ball or roller bearing in the elevator tube? Seems that this would be a good location for some friction reduction.

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Yes, all moving joints that your fingers are in command of utilize ball bearings. This includes cable ends as well as can be seen with the REP control bearings on the ELE horns.
Most of the rudder joints will also but some of the pivot points in the pedals will be sleeve bearing. The rudder itself rides on ball bearings though.
So far my largest expense has been in bearings. That includes the initial tube order.