My New Lawn Ornaments

Catching Up: Part Deux

While it might not be obvious to anybody but me, there have been two other shining points of progress over the last two months.  First was the construction of the 4 rear bulkhead supports.  These will serve dual functions of strengthening the rear bulkhead, as well as being the lateral seating supports.  They're not actually tacked on in this picture, just mocked up.  Second is the lateral tube and diagonal just aft of the shifter on the transmission, which are tacked in place now.

It should come as no surprise that there is unlikely to be any physical progress over the next week or two, however it's not for the usual reasons...I am actually in the process of sorting out the rear suspension geometry so that I can finish planning the rear bulkhead bracing.

Catching Up: Part 1

Between SWMBO teething, the Plague ravaging our household, more teething, and now more Plague, there has been a precious little time to spend on my dithering in the garage.  Let alone updating on my (lack of) progress.  However, I do have a few updates to make.  So I might as well get started on the longest one, while laying here bed ridden and recovering from my latest brush with death...Also known as the "man cold".

Back before the turn of the year, I once again turned to painters tape in an effort to simplify the measurements and calculations required for cutting a couple of tubes.  The difference this time being that these tubes were for multi-axis (3D) angled ends.

As before, lay out the desired tube path with tape.  This time, with two pieces of tape forming the opposing sides.  I found it to be much more accurate and stable by 'sticking' a small piece of scrap tube between the two pieces of tape near each end to help place the tape.  Then wrap tape across the 3rd side to form the 'top' of the cut, as well as mark the two 'sides' for finished length as well. Hopefully this picture will be worth enough additional words to salvage my poor description.

Now the tape can be removed and wrapped over the actual tube being cut.

Trim the excess.  Note that the 4th and final edge can be found by drawing a line between the 'bottom' edges on the two sides.

Now be careful how to set this up in the saw.  If done wrong, it will cut off needed extra length.  If done right it will indicate what needs to be ground off, as pictured below.

Color the excess material in with Sharpie (finally a good use for the Industrial Sharpies) and take it to the bench grinder until the Sharpie is all gone and the tube fits.

I must admit that this method and/or my execution are not as perfect as the 2D tape method.  As the tubes move out of plane with each other, the 1" wide face of the tube being intersected becomes less-than 1" relative to the intersecting tube probably plays a part here.  I'm sure that I also just need more practice.  The end result was that the indicated grind area was a bit on the conservative side, and I actually just needed to grind off a little more metal than the tape line indicated...Which is great, because I really hate trying to grind metal back on to the tube.

Tongue Twister

Transmission tunnel triangulation tacked.

Garage Essentials

I picked up some garage essentials this weekend...Maybe this will finally solve the Sharpie-Cockroach Paradox.

Blue Painters Tape

I'm not sure what it is about painting supplies, but they're just so damn useful for stuff other than painting.  I had previously written about using the stirring sticks for setting the angle on my band saw.  Now I'm using painters tape to lay out and cut my tubes to the right...err...correct angles and lengths.

The basis of this technique is something that I picked up from a friend for making compound angle cuts.  However, I decided to use it to see if it might also be able to simplify cutting some types of 2D tubes as well.  A diagonal tube between parallel planes in a rectangular opening is relatively easy to math it out.  But it adds another layer of complexity when the opening is not rectangular, nor symmetric for that matter, and the tube is not between parallel planes.  Thus I figured this would a perfect time to practice an alternative technique.

First I spent some time figuring out exactly where I want the tubes to go.  These tubes also happen to be going beneath the transmission. So I had to make sure to avoid the lowest parts of the transmission, try to leave at least some emergency access to the drain and fill plugs, and adhere to my personal guidelines of avoiding overlapping weld joints and angles tighter than 45 degrees.  The latter of which I forgot about last weekend until after the tubes were cut, sending me back to the drawing board...Literally.  No fancy CAD programs here.  Just good old fashioned graph paper, a pencil, and a ruler.

The process then starts laying painters tape across the span where the tube will go.  Measure out the desired corner points based on the design, marking them with a Sharpie.  After that, use a large enough straight edged device and play connect the dots.

Since the Sharpie can be seen through the tape, I find it easiest to lay the tape sticky side up on the table and align the tube on top of it.  Then flip it over to clearly see where the cuts will go.

Now my band saw only angles in one direction.  To cut angles the other direction, you simply flip the part over.  With both cuts going opposite directions, only one of them can be cut with the tape side up.  Align the cut line on the tape with the cutting blade, lock it in place, and let it rip.

With the tape having been cut as well, it now becomes the transfer pattern.  To make it stick to the other side of the tube, place a couple strips of tape sticky side up on the table, lay the transfer pattern tape sticky side down on top of them, and align the tube on top of that matching up the previously cut ends.  Now wrap the sticky side up tape strips around the tube to hold the transfer pattern in place.  Roll the tube over to see where the cut needs to go, and using a center punch or scribe, mark the desired cut line in the tube.

At this point the tape can be removed, revealing the line to cut.

And voila, a finished tube!

Lather, rinse, repeat.

I knew from the start that this method might provide slightly less accurate cut positions and angles than I get from my hand calculations, but it proved to be quite a bit more accurate than I had anticipated.  I was impressed with how easy this technique was to get a feel for, as well as how little 'massaging' will be require to finalize the tube fitment.  Just remember that it's a LOT harder to cut material back onto the tube, than it is to cut more material off.

SWMBO

Somehow the acronym SWMBO (She Who Must Be Obeyed) never really seemed appropriate for my wife, so I gave her the much more deserving title of SWEETA (She Who Enables Every Thing Automotive).  Maybe it was a coincidence, and maybe it was a premonition.  There is no way to know for sure.  What I do know is that with a baby girl in the house there is one, and only one, SWMBO...And it certainly isn't my poor SWEETA.

 As weeks turned into months of virtually no progress, in the back of my mind I did start to wonder when I would ever be able to get back into the swing of things with this build.  Fortunately, SWMBO has appears to have recently approved my request to exchange the previous weekend mornings for weekend nights, by regularly falling asleep considerably earlier.  Additionally SWEETA has given this new schedule her blessing as well, by also choosing to go to bed at that time.  Thus, for the past 4 weekends in a row I have gotten garage time!

Unfortunately, I have spent more time that I care to admit relearning some of the things that I was doing without giving a second thought before SWMBO arrived.  Consequently, I have also spent far to much of this precious time redoing said things...Often more than once.  As of this weekend, it feels like it's all starting to flow again though.

Current progress is limited to having tacked in the tubes from my last update, and having cut the 4 additional tunnel diagonals sitting in the chassis as pictured below.  Yes the chassis as pictured is currently up on its side, so that's three bottom diagonals and one upper diagonal.