The XPB Stage 1 underway.

[geoffreywh]

Integral power trim tabs ? or add on?

 

 

[bexrbetter]

Integral power trim tabs ? or add on?

I have an idea for that, allowances have been made towards it, but not important relative to just getting it flying first then sorting out the secondary details.

 

I didn't mention that the rear wing is 2.2 meters wide, i.e., legal trailer size and slips into a container.

 

 

[Birdseye]

I have an idea for that, allowances have been made towards it, but not important relative to just getting it flying first then sorting out the secondary details.I didn't mention that the rear wing is 2.2 meters wide, i.e., legal trailer size and slips into a container.

I'm assuming that in this F35 era you'll be employing canbus and fly by wire.

 

 

[bexrbetter]

... you'll be employing canbus ...

I find the occasional whiskey helps me to relax while designing, but I think I'll stay clear from smoking dope.

 

 

[bexrbetter]

So, paid a bit more attention to the sheeting today, I am extremely happy that the matched holes all lined up on the rib's tab holes without any hassles.

 

I was expecting to have to drill out some holes, and move them around on the computer 2D because the tabs are bent over each on a different angle to make the curve, this with the slightly varying radius as they are bent over by hand would not unexpectedly create some variances - but I got a little lucky there.

 

 

 

 

.. But first I had to bend the sheets over for the front radius, never my favorite task, but went ok ......

 

 

 

[bexrbetter]

It's twins!

 

 

 

 

[Marty_d]

You are The Flash of aircraft building! (And please don't provide a photo of that.)

 

 

[bexrbetter]

Mostly sheeted the HS but not entirely happy with my piano hinge mount arrangement for the elevator, so may change it yet ...

 

 

I also picked up the 25mm spacing drilling jig strip rather than the 30 mm, so there's too many lateral rivets.

 

 

[Bryon]

Oh no!!!! you made a mistake, how could you?

 

Dont worry Bex, you can fix it

 

 

[geoffreywh]

So when you bend the front radius of the elevator sheet how do you get the pre drilled holes to line up with the holes in the ribs ? There must be a jig or something to get the bend in exactly the right place, I mean, within a couple of thou. it looks as though that is really critical? ................The sheeting (from the picture) is already drilled. Maybe you drill the ribs after the bend?

 

 

[bexrbetter]

So when you bend the front radius of the elevator sheet how do you get the pre drilled holes to line up with the holes in the ribs ? There must be a jig or something to get the bend in exactly the right place, I mean, within a couple of thou. it looks as though that is really critical? ................The sheeting (from the picture) is already drilled. Maybe you drill the ribs after the bend?

It's not that critical.

 

There is 3 holes across the sheet (that are on the leading edge that need filling later) that I rivet to a 25mm pipe of sorts, thick plastic plumbing pipe in this instance.

 

I merely wrap the sheet over the pipe, pop rivet 3 holes on the trailing edge and then push it down evenly with a strong 40 or 50mm square steel tube just behind the 25mm pipe with my body weight.

 

I then do the final just behind the 25mm pipe with clamps over the edge of the table.

 

 

 

[Bruce Tuncks]

Thanks Bex, please keep the reports coming and good luck.

 

Today I worked on a "matched hole" garden shed from Bunnings. Some of the holes did match, others needed the screw to be entered at an angle to find the second hole with the pointy-end, and some needed drilling so the second sheet now has 2 holes, with the screw in the second hole.

 

Mind you, the shed was only $220 bucks or so and I would buy it again, but in the meantime I am in awe of matched hole stuff if it really works, but those of us who have built $220 garden sheds will need some convincing.

 

 

[Marty_d]

Well bugger, there goes the $220 aircraft market...

 

 

[geoffreywh]

Fiendishly clever, the holes in the plastic tube are the jig! This is why I'm not a toolmaker!

 

 

[bexrbetter]

but those of us who have built $220 garden sheds will need some convincing.

Likely stamped and folded parts produced en mass by gruff men who think tolerances are coming home to a cold dinner, whereas mine are lasered, folded with forward planning (too long to explain that one) and each part is tenderly caressed, loved, have quiet lullabies sung to before being sent on a skiing holiday to the Swiss Alps. Only then are they allowed to be a part of my developments.

 

 

[Birdseye]

Likely stamped and folded parts produced en mass by gruff men who think tolerances are coming home to a cold dinner, whereas mine are lasered, folded with forward planning (too long to explain that one) and each part is tenderly caressed, loved, have quiet lullabies sung to before being sent on a skiing holiday to the Swiss Alps. Only then are they allowed to be a part of my developments.

So it's all down to psychology..... they want to be aligned.

 

 

[Bryon]

So it's all down to psychology..... they want to be aligned.

Are you sure it is a real need and not just a temporary fixation with modern psychological consumerism driven by greed

You cant trust these little buggas

 

 

[Bruce Tuncks]

The RV planes use a smaller pilot hole for the matched stuff. The hole is just big enough for a small cleco. So you need to remove a cleco, drill to size, debur, dimple and set a solid rivet. Maybe corrosion-proofing and maybe using a bucking bar.

 

The Zeniths use full-size predrilled holes , I'm not sure if deburred, and pop rivets. Much easier and faster, but more drag.

 

Bunnings garden sheds have holes to size and sheet-metal screws with sharp points. It takes a lot of skill to not strip the hole when you do up the screw. I hope it's not going to fly at all.

 

 

[bexrbetter]

The RV planes use a smaller pilot hole for the matched stuff. The hole is just big enough for a small cleco. So you need to remove a cleco, drill to size, debur, dimple and set a solid rivet. Maybe corrosion-proofing and maybe using a bucking bar.The Zeniths use full-size predrilled holes , I'm not sure if deburred, and pop rivets. Much easier and faster, but more drag.

I use both methods and whatever else is easiest for each particular situation.

 

 

[Guernsey]

Hey Guys and Gals, with bexrbetter now approaching 750 posts, how about we all have a guess at what post he will be announcing completion of his aircraft.

 

I'm not trying to be sarcastic here as I am enjoying the 'Postal' journey but a prize for the one who comes closest could be a hard cover edition of all the posts and photos of this incredible and entertaining journey.....how about it Ian.

 

I'm guessing that it will be 1496.!!!.

 

Alan.

 

 

[SDQDI]

973

 

Ps I think Bex should be excluded from this as he can obviously rig it!

 

 

[Bruce Tuncks]

I reckon Bex's posts are among the best. I have learned a lot from his stuff, on politics as well as engineering.

 

Thanks Bex!

 

 

[Litespeed]

I reckon about 1269 should do it.

 

A lot of earlier posts were experimental and it is maturing well.

 

 

[fly_tornado]

I reckon Bex's posts are among the best. I have learned a lot from his stuff, on politics as well as engineering.Thanks Bex!

how do you reconcile the fact that Bex is an immigrant in Ch-ina and your political views on immigration? it's catch 22 really

 

 

[rgmwa]

I'd say Bex is perhaps 25% of the way to a flying aircraft at this stage, so say an even 3,000 give or take.

 

rgmwa