Extended Reach Drill Bits

JPigg55

JPigg55

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I'm in need of a few extended reach drill bits.
Looking around, I see various types like: Extended Reach, Chip Clearing High Speed Steel Extended Reach, & Short Flute Extended Reach.
Wondering what the advantages/disadvantages of the different types were ?
Also wondering if anyone sells them in small sets (5 or 6 sizes) vs full type sets running $1000+.
Buying singles is option, but thought small sets might come with price break over singles for same number and sizes.

Was working on a part that I couldn't drill ( on lathe) all the way thru with standard drill bit.
For prototype, I'm using aluminum and just reversed the piece and drilled from other end.
Drilled undersized and used reamer to finish and true the hole, but final piece will be stainless and not sure if this meathod would work very well.
 
I hate using long drills & avoid it if I can. I don't see why boring wouldn't work. I have bone it on welded pipe & only thing was I had to do a bunch of passes to get the taper out.
 
What size extended drill do you need , are you reming to final size I have a bunch of good ones somewhere
 
if you are in a pinch and need to have a longer drill,
get a piece of rod larger & longer the length required, plus a little, than your drill bit needs to be and chuck it up.
centerdrill and use the drill you'd like the inteded hole size to be.
drill the bore to an acceptable depth to hold a brill bit, about 1/4" deep per 1/8" of drill bit diameter.
cross drill & tap the rod to accept a set screw and
Baddabing, you have an instant drill bit extention!
 
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I've used super long drills a couple of times, actually one that ulma doctor gave me :) first time i just had at it with the long drill and it came out somewhere completely unintended. second time i used a stub drill, then a jobber and then the long one (6" long 1/8"), pecking 1/4" at a time and blowing chips out. worked a treat as the hole drilled straight for the full 4". every tool has its use, just have to use it right :)
 
for long drill bits I just silver solder an extension on by butting them together with a little flux and they work perfect---if you are needing them perfect--then just be exact as you line them up--your extension can be a smaller diameter as long as you shim them to line them up or you can turn them down a bit in the lathe----I've never had one break at the silver soldered joint---Dave
 
The advantages/disadvantages of different types depends largely on the material your drilling and how hard you're pushing the drill. In our (hobbyist) shops, speed (cycle time) isn't usually the driving factor. Just get a drill long enough to do the job. follow recommended speed & feeds. Start with a short drill (stiffer) to get the hole started straight. Change to longer drills as requires. Peck and withdraw as required to keep the chips from packing.

Short flute extension drills are for drilling thin material when you need the 'reach'.

I don't know of anyone selling "small sets" that you mention. I just buy what I need to get the job gone (+ a spare) and eventually, I have quite a few.
 
I have always referred to them as aircraft drills (1/4" or less). Try Ebay, I purchase a few USA made (precision/champion) some years back. What size are you after?
I also have a dedicated drawer with modified chucks, drill bits and such for jobs that required a deep reach.
I like many of the recommendations so far too. Without knowing the size, its limits further recommendations.
 
Suggestions change depending on if your drilling a 1/8" hole or a 1" hole. It also depends on if your drilling 4" of solid or your reaching 3" & drilling 1". If you have a pilot hole above it where your drilling that is much bigger then the hole you need then Ulma Doctor's suggestion is probably the best & easiest to use. If you need to cut 6" of 1/32" hole I'd say it is almost imposable & you should find someone that can burn it for you.
 
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