December 6, 2007 drill some holes...
cut some tubing
Or so I thought...
Started out thinking I would chuck the horizontal tubes in the micro lathe and have all eight holes drilled in less than a half hour. After accomplishing that I'd still have
an hour and a half to cut the 1/2" tubing and start laying out the brake pedals. WRONG !
Because I ground down the ends of the horizontal tubing they weren't perfectly "square." We'll round tubing isn't square but when you place it in the micro lathe's chuck you need a length
of tubing to be perfectly straight so that it "seats" square in the chuck. I didn't have that amount of "squareness" and thus... the tubing was out of alignment for drilling a hole in the center of
the end pieces, the caps as I've called them. With my delimma in hand I needed to come up with a solution for getting those holes in the center of all eight caps.
Between fiddling with trying to make the micro lathe work and figuring out what I was going to do for centering the hole on the caps I "wasted" about an hour and a half. Kinda shot the idea of starting on the brake pedals right in the foot.
To drill the holes in the end caps... I decided that I'd take a piece of 2x4 and clamp it to the drill press table, drill a 7/8 inch hole in it, insert the 7/8 inch tube into it and start the three step process of marking with a center drill, then under-size drilling, then reaming to
it's final 3/16" size.
OK... I thought... I won't get to the brake pedals but I'll get all eight of these holes drilled and reamed. Or, so I thought.
Does this crap only happend to me ???? Inserted the first of four tubes in the 2x4 jig I made, chucked the center drill, made my mark, chucked the #18 drill bit (remember it needs to be under-sized, the guys on the biplane forum said 1/64th under or .005 under - take your pick), a drop of cutting fluid and
I begin to make my mark... a little more cutting fluid, a little more cutting fluid, a little more cutting fluid (alluding to a Cheech and Chong routine if you didn't catch on to that.) After a few minute I have a nice round hole.
Tube number two in place I begin the process over again. I start to drill, and drill, and drill, and drill... seems like it's taking a looooooong time to make this hole. Did the first one take this long ??? After about 15 minutes of going nowhere with the bit I chucked another one and had the hole
cut in about two to three minutes.
Unbelieveable ! I spent good money... not just good money... I spent a sizable amount of money on these bits so I wouldn't have this problem. I wasn't too happy wasting my time with a "faulty" drill bit. Did that bit get dull in one pieces of .100 material ? I can't see where I did something wrong. Wouldn't be the first time I
couldn't see my mistake but I laid down a plan for making this a painless process only to be kicked in the ass with a HUGH problem. Not to mention wasting 1 1/2 hours of my time.
I'll make a call to ACS tomorrow to straighten this out. Maybe a single new bit or a new bit set. I'll let you know.
Sorry for the rant... but that's what this thing is for some times.
Had the day off today. After a few hours of Christmas shopping I headed toward the aeroplane work shop and set about drilling those holes.
Decided to give the POS drill bit another try. Picked it up from the spot that I left it last night and in the light of day, literally, in day light I saw that it was
the wrong drill bit. The cobalt bits that I got from ACS are a bronze color... the one I chucked last night was one of those dirty gray looking things you get at the local hardware store.
I didn't see the difference in color last night in my, apparently under-lit work shop. I'll have to let ACS know they can come back from hell... the place I cursed them to last night.
OK... enough of that... I need to get these holes drilled. Chucked the correct drill bit into the drill press and drilled all the remaining holes in under a half hour. Took a look at them, and even though I was
careful to make them centered on the cap... I wasn't happy with them after taking another look at them. I refuse to begin the "it's acceptable" train of thought in my building so looks like I'll be remaking these.
Grabbed some .100 4130 flatstock from it's place and cut a chunk of it off. Clamped it down to the drill press table and cut nine caps (one spare) from it then took some 7/8 x .058, yes... .058 NOT .049, and cut the
four horizontal pieces that the caps get welded to.
Stopped for the day... other things to do. I've just had one of those learning experiences. I know not to grind down the excess weld as much this time, or at least not until I've finished chucking it in the micro lathe and
cutting those perfectly centered holes.
And another thing... I need to go out and get a few more lights for the shop.
Still another thing.. what did I learn last night? Make damn well sure you know what you're working with. That could have just as well been a drill bit that was too large... drill an over sized hole and you're looking at remaking the part.
Oh, and that size twelve I mentioned earlier... it's to kick my arse for making such a stupid mistake.
More of the same tonight. The time just flies. Two hours are gone before you know it.
Ground down the excess weld on the two remaining tubes I've been working on... chucked them, used the center drill to start the hole, drilled the under-sized
hole then reamed to the final 3/16" hole. Took them to the 6" disc sander and used 60 grit to grind the excess weld on the caps then finished with 150 grit.
Yeah... that took me two hours. I wasn't slow, I wasn't fast... I was moving along at a good pace and it still took two hours.
Tomorrow I'll make the jig for the brake pedals, cut the tube to size and then at least tack weld them together. Hopefully I'll have this all put to bed by the end of this
week.
Click here to see how I centered the holes in the end caps.
Yesterday I took the plunge and welded up the horizontal tubes that connect to the brake pedals. Welded on all eight caps, ground down the excess weld and then sanded them smooth
with 150 grit sandpaper. Felt reeeeeeal good to start welding up an actual piece of the biplane.