Ready for ribs

Well, the work bench is cleared off — well, at least enough to get both jigs on it.  I’ve got a couple dozen sticks of geodetic brace stock shaved down.  The epoxy syringes are filled.  All I need now is a razor saw and a steam setup.

Yes, I have a razor saw.  Somewhere.  I pulled it out during the kitchen remodel, and I remember seeing it in a box of tools we were using, but now I can’t find it.  It’s a Zona, good quality but inexpensive.  A new one is on the way.  Two, in fact; one medium and one fine tooth.  I also have a steam box that I built for the capstrips, but I’m unsure whether I’ll use it in the basement.  It takes  bench space (which I now don’t have down there), and drips water out the end by design.  I’m thinking about ways I can use it vertically.  I had looked at rigging up a piece of pipe or something with a heating element for hot water, but it looked like an awful lot of extra work considering I’m over halfway through the ribs.  I’ll probably need it for the tail and wingtip bows as well, but I’m not entirely sure yet how I’m going to steam 6 to 9 foot long strips of wood.  Tonight I tried soaking half a dozen capstrips in a bucket of hot water for an hour — we’ll see how well tat worked. 

Back at it…

Well, I thought it had been a lot longer since I did any construction, but I see it was only back in February.  I really wouldn’t have been surprised to find that I’d gone an entire year without building anything.  But, I’m getting ready for winter and more building.  To be honest, I’d had second thoughts recently about even continuing with this project.  Sometimes it seems like such a massive undertaking, especially when I see pictures of guys attaching the wings and getting flying wires made and rigging done…  only to tear it all apart again and then start covering.  Covering!!  How the hell an I ever going to cover this beast?  But then I decide that maybe I’ll keep at it after all.  Hey, it’s relatively cheap…  so far…  as hobbies go.  It keeps me occupied for as long as I care to work on it, and nothing bad happens if I let it sit idle for a while.  Even a long while. 

Over the past few days I’ve been working on getting my absolute pit of a basement workshop cleaned up at least enough to be able to move around and use the workbench.  A new water softener installation, a kitchen remodel and a few other household projects meant there was a lot of mess left over, and a whole lot lot of crap got just piled everywhere.  Most of it’s cleaned up.  Not enough, really, but at least enough for me to be able to take stock of where I am.  In hindsight, I suppose I could have, you know, looked at my blog posts, but where’s the fun in that?

I need 26 normal wing ribs, and they are all done.  I need 16 aileron ribs — the same as the normal ribs, but just missing a couple of cross pieces.  Of those, I have built ten, so there are six left to build.  Then there are 34 false ribs — just stubs from teh leading edge back to just behind the main spar.  I’ve built one of them, so 33 left to build.  Those should be quicker to build, since there are only about a quarter of the geodetic braces to cut and glue.  Unfortunately, each will still occupy a full rib jig — so two at a time is still the limit.  Unless…  maybe after the aileron ribs are done, I can tear down one of the rib jigs and rebuild it to do several false ribs at a time.  I think keeping one rib jig intact would be good, just in case I should ever need to build more ribs for a repair or whatever. 

I’ve got a bunch of geodetic brace stock sanded down to the correct thickness.  Enough for sure to do the rest of the aileron ribs and get a good start on the false ribs.  I’ll probably do half a dozen more, then put the oscillating sander away and maybe knock out a few ribs.  I’m starting to get a little fired up again. 

Slow progress

I’ve knocked out a few more aileron ribs, two at a time.  I’m about halfway through them and trying to speed things up a little, so I don’t die of old age with a half finished airplane.

Yesterday I decided to use up a piece of obviously bad capstrip Aircraft Spruce saw fit to ship me.  This piece has a large chunk missing out of one edge, part of a knothole or pitch pocket or something.  Part of it is in no way suitable for aircraft use or much else for that matter.  But – there’s enough good wood there to use it for false ribs, so I made one of those.  That went OK, but it’s apparent that I will need to soak the top capstrip in HOT water for the false ribs.

I’m looking forward to starting work on the tail surfaces.  I’m planning to get out to the garage and clear off the workbench this week, lay out the plans and see exactly what I will need to get started.  The wood called out is white pine, so I’ll start checking the local places for suitable pieces of white pine or Douglas fir…  a little heavier, but I know Menard’s sells some good boards from which I can cut suitable pieces for the laminations.

Back at it – more ribs

Got the basement workbench cleared off enough to move rib production indoors.  So far I’m only using one jig, but I’ve knocked out two ribs now.  I need to get the second jig set up.  One rib per day isn’t going to cut it.  Sure is nice working in the basement instead of the garage though.

It’s damn cold outside!

I’ve been wanting to get back to building ribs.  The garage bench has been piled too deep to get anything done, and now it’s been below zero for over a week solid.  Insulation or no, it’s damned cold out in the garage.  Too cold for epoxy to cure, and too cold to work.

So…  there’s a perfectly good work bench down in the basement.  8′ long and rock solid, built by Dad back in the 1960s.  It’s been pretty much completely covered up for the past several years with a collection of parts, partially-disassembled or -assembled prototype projects and assorted debris from the side business I was running, plus a CNC router that took up about 3′ of it.  I have cleared most of it off (much of it into a trash can).  The CNC machine is shelved for now; I’ll maybe resurrect it when needed at a later date.  It will probably come in handy for cutting the instrument panel and/or nose ribs.

The next issue is containers for the geodetic rib braces.  There are 24 braces used in each rib, all of which are of course slightly different.  Just enough so that none are interchangeable.  I was using paper cups to hold them in the garage, but it’s a completely unsatisfactory solution.  In the basement I think I’m going to try stapling taller plastic cups along the back edge of the bench and see how that works.

I’m not moving power tools down there from the garage, so new geodetics will be cut with a razor saw.  We’ll see how that works out…  it’s one of those jobs I wish I could set up a machine or fixture to do.  It’s 24 different lengths with over 40 different angle cuts, so I’m not sure how I’d make that work.  Even cutting them out in batches on the band saw meant fine-tuning each one with a sanding block before assembly.  It’s fiddly work and tedious as hell.  Classic gusseted ribs would be a whole lot faster and easier to build.  If I were starting this over I’d probably just depart from the plans and build them all that way; I’d probably have them all done by now.

 

Getting ready for winter…

It’s only late August, but I’m trying to get started on cleaning up the garage / workshop for the winter.  I can’t build in its current state.  Too many other projects, too much clutter.  I’ve got to get stuff put away, thrown away, stowed, etc.  Then I want to get the rest of the geodetic strips shaved down for assembly, so I’m not out there all winter miserable as I run them through the sander.

Mixing epoxy

I’ve been mixing epoxy in the little plastic medicine cups using “craft sticks” (think Popsicle stick).  I thought I was doing a pretty good job of stirring, spending some time scraping the sides and swiping along the bottom corners of the cup to ensure everything was mixed up.

Last night I mixed up about 2 cc of epoxy, mostly just to try out my new syringe dispensers.  I let it sit in the cup with the stick propped up in the center.  Today I popped the slug of glue out of the cup.  Lo and behold, there are sticky spots around the edge!  Nearly all of the glue is perfectly hard and cured, but there is just a tiny little bit of uncured epoxy right around the bottom edge.  Apparently the stir stick is not a good tool for making sure ALL of the material gets mixed together.

In light of that discovery, today I did another 2 cc sample.  This time I did the mixing with an acid brush with the bristles trimmed down to about 1/4″ to 3/8″.  After mixing I cleaned the brush out with a little MEK, just to see if that would be worth doing or not.  We’ll see how that one turns out after the epoxy has had a chance to cure.  Acid brushes are pretty cheap, so even if the MEK cleanup doesn’t work out it’s not a big deal.  You can buy the brushes by the gross for around $0.12 to $0.15 each.  But what will I do with about 950 craft sticks?  Good thing I have grandkids.

 

Prep work

I’ve been away from building for a while dealing with a remodeling project, the annual condition inspection on the RV-12, Oshkosh and few other odds & ends.  At Oshkosh I discovered that the wood shop guys had actually saved my miniature wing rib from last year (2016).  I brought it home with me, of course.  Last night I pulled the staples, cleaned it up and sanded it, and gave it a coat of clear polyurethane.  I figure it will make a nice wall decoration for my office.

Last night I also started cleaning up some of the enormous mess in the garage so I can get back to building.  I’m not quite there yet, but tools are slowly making their way back into drawers and onto pegs.  It may take a few more days, but it will be nice to get back out to a garage that’s not a complete disaster.  There are 14 wing ribs hanging on the wall, and the guy on the Biplane Forum is catching up with 11 finished.  He can work faster, since he can pull his ribs out of the jigs as soon as they are stapled.  I need to step up my game!

I did pick up a good idea from that discussion — using cut down acid brushes to mix & apply the epoxy.  They’re cheap, and it looks like I might be able to get more precise application of the glue where it’s needed, in the amount needed, with good penetration into the wood grain.  I’m anxious to try that, I have a handful of brushes here.  And, I got some of the epoxy  into 60 cc syringes so I can dispense exactly the same amount of each component.  I know it’s not terribly critical with T-88, but I still want to be as accurate as I can.

Fixing up the steamer

I built two more ribs last night and took them out this morning; I’m up to 14 now.  I’m trying to 3D print some clamps too use on one of the jigs that has locating blocks too thick to use the small red sprig clamps I bought.  of course first I have to fix the 3D printer…

When I used the steam box, the door warped — no, curled outward.  I flattened it out, but because everything isn’t perfectly square it really only fits on one way so I can’t just flip it over.  Tonight I cut a couple of 3/4″ square stiffeners and epoxied them to the outside of the door.  I need to bend some more pieces of capstrip, and I can’t do that until the door is usable.  We’ll see if this is enough or not, should be interesting at least.

Built a steam box

Last night I built a steam box out of 1×6 boards.  All that remains to be done is to put some foam weatherstrip on the door and run a few dowels through it to get the wood off of the bottom of the box for steam circulation.  The steam generator arrived a few days ago, so once I get the box finished up it will be ready to go.  I found that the Wagner steamer hose will mate with 1/4″ pipe fittings.  I spent a little extra for brass rather than galvanized iron.  I also re-worked my bending form with a gentler curve, providing a fairly close match for the rib shape.  It won’t give me a perfect fit, but will get the capstrip close to the curvature needed.