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Fractional vs Numbered bits

So I got the majority of tools in for my toolbox project kit, but I'm missing the drill bits. I'm sure this wouldn't be a good idea for the aircraft, but would it matter if I used 1/8" and 3/32" instead of #30 and #40 just for the toolbox kit? It looks like Lowe's and Home Depot don't sell the numbered bits locally and I'd love to get started learning!
 
Try a couple holes. If the rivets fit and the dimple dies fit (they all might not) you can do it. But I'd strongly recommend the correct size for the airplane itself.

DON'T wobble out the holes to get the rivets or dies to fit. Try to keep the holes straight and true.

Your local hardware store might carry numbered bits.

I've found that #40 and #30 reamers are handy, too, along with 12" drill bits.... The tool monster influences most of us at one point or another.

Dave
 
Simple answer no

So the simple answer is no, the 1/8 and 3/32 are pilot holes for the #30 and #40. The -3 and -4 rivers wont fit in 1/8 and 3/32 holes. Also, when I tried to dimple a 3/32 hole ( one I forgot to ream to #40) the skin cracked. I had to stop drill and use an alternate rivet nearby.

My Ace Hardware store carries numbered drills. My local home depot and lowes do not. I buy all my drills from Browns Tools.

Also get some longer ones like 6” and 12” #30 and #40; you will need those.

Tools are cheap compared to poor quality of a build.
 
I am not a big fan of Harbor Freight for quality tools, but ... I bought a numbered drill set at HB (#1 through #60) just for occasional use and I was surprised how often I use it. #43 for drilling out AD3 rivets, #33 for an 319BS pulled rivet, etc.

For my regular bits (#40, #30, #12, etc) including the long ones mentioned, I would use an aviation tool provider for high quality bits, but the complete set comes in handy.
 
Order up your drill bits from Brown Tool. Super fast service, they are keeping the employees working during this crisis, and their prices are excellent. They are having a discount special until 4/15/2020. Their drill bits are made in USA and are high quality bits. When I order, I order a dozen of the #30 & #40 bits so I have them on hand and just throw them out when dull. I prefer to ream the pre-punched match holes, but that subject matter can turn into a "Primer Wars" style debate. :D Like mentioned, a 1/8" hole is undersize and prone to cracking. Even so, I lubricate the skins before I dimple and clean it off afterwards.
 
You will also want to order a handful of 6" and 12" #30 and #40 drill bits. Probably six of each should get you through the entire build.
 
HF bits

Just pick up one of these for the unusual sizes, get several of the #40, #30, #19, #12 bits from a solid supplier, pick up a few reamers, and you'll be set.

https://www.harborfreight.com/cobalt-drill-bit-set-115-pc-61886.html

61886_W3.jpg
 
Tool box

For the tool box, go to Ace and buy one each #30 & #40. That will get you through the practice kits. Drill apart and reassemble.
For the plane, I actually have the HF drill set mentioned but all holes are reamed to final size with quality reamers. The HF bits are used to get pilot holes and intermediate holes to size.
 
IMO, going cheap on drill bits is foolhardy. Sharp bits center more easily and drill more precise holes. Get a package of 20 each of Number 30?s and 40?s. If a drill bit hits the floor, toss it. If it gets dull, toss it. They are cheap. Also for sheet metal work get 135 degree split point drills. You won?t find these in a hardware store. MSC, brown tool, or Cleveland tool are goos sources.. For stainless, get a couple of colbalt bits.
 
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