why are drill blanks so expensive

Fish30114

Fish30114

Joined
Jan 5, 2014
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I found myself wanting to confirm some hole sizes and decided it would be good to a set of drill blanks to my tool collection. I began looking around, wanting a chepo set, and found that all the sets I could find were much higher in price than cheapie drill bits. I can get a 110 pc set of drills numbered, letter and by 1/64 to 1/2" for less than $50, but drill blanks are out the roof.

Looking for info on why and if anyone knows of a cheap source for blanks.

Any info/input is welcome.
 
Are you talking about gage pins or drill rod? How close do you need to measure the hole sizes?
 
"Why" is because the drill blanks you looked at are probably sold as a gauge set, meaning very close/precision ground tolerances. Drill bits are stock material, not as high tolerance.

Buying a full set, with all sizes is probably something very few people do (like the Quality Manager in the QC department in a precision machining shop). Drill bits wear out and are bought in much higher volumes.

This is the "why". I'm sorry I can't help with the where part.
 
Fish30114 said:
I found myself wanting to confirm some hole sizes and decided it would be good to a set of drill blanks to my tool collection. I began looking around, wanting a chepo set, and found that all the sets I could find were much higher in price than cheapie drill bits. I can get a 110 pc set of drills numbered, letter and by 1/64 to 1/2" for less than $50, but drill blanks are out the roof.

Looking for info on why and if anyone knows of a cheap source for blanks.

Any info/input is welcome.
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For starters that chinese cheapo drill set is crap


I bought one of those.

Unless it says High speed steel, the drills are carbon

The ones i had were poorly heat treated, probably overheated
The drills were brittle, not straight and snapped off with huge grain size

Once I broke several, I went through to ID the ones I needed to replace
There were 7 drills duplicated. The wrong sizes stuck into the holes to fill the set, so 7 sizes missing in addition to the broken ones.

That cost the price of the set all over


The drill blanks are much less appealing to mass market homeowners.
They are probably made or sold by more reputable firm of quality materials.
 
Yeah. So like TR said, having a set of pin gages isn't generally something even a professional machinist has in his personal tool box, but the shop likely owns a couple sets in different ranges.

I asked how accurate you need to measure holes because pin gages are about the most accurate way to check form/size/go/nogo, but that type of accuracy isn't really necessary (in my opinion) for knifemaking. Even if you're building folders, since unless you're making the pivots yourself, how does knowing your pivot hole is .1885 rather than .1878 make a difference? Unless I guess you're picking through a batch of pivots to find the exactly clearance you want.

If you have a micrometer already, and a caliper check for hole size isn't sufficient, I would suggest buying a set of small hole gages. Link to Starrett for example, you don't need a Starrett set necessarily. There is a bit of feel to using them but they will give you a better idea of hole size than a caliper for less money than a set of pin gages. http://www.starrett.com/metrology/m...isplayMode=grid&itemsPerPage=24&sortBy=wp/asc
 
Drill blanks are hardened steel rods with a size tolerance from end to end of .0000-.0005". Drill bits are whatever tolerance the are, but they may be quite irregular from the end to the shaft, and from bit to bit. Blanks vs bits is apples and oranges.

Your question is sort of like, "Why is a granite surface plate so expensive compared to a slab of scrap granite from the countertop people?" One is measures and certified to be precise and the other isn't.
 
What about a set of small hole gages and a mic?
 
Well, I guess that's a forest for the trees question--I just didn't realize that blanks were held to that much tighter tolerance. Kuraki, I don't really have a specific need for that accurate of hole sizing, I just wanted to be able to take a blank and match it up to any given hole and see what size(s) would be good for pin stock or such. I just thought if say -Dewalt- made a fairly accurate set of bits from 1/64-1/2 for $69.00 that they could just leave the flutes out and sell a set of 'blanks' pretty damn cheap...and yes I have several good micrometers but don't have hole gages or pins
 
Drill bits work fine for that, just use the shank.
 
Drill bits are ONLY close to listed size generally smaller diameter than actual pin stock diameter. Chucking reamers can be your friend to open up the hole and if its a precision hole a lapping tool will polish it up nicely.
 
Busto said:
Drill bits are ONLY close to listed size generally smaller diameter than actual pin stock diameter. Chucking reamers can be your friend to open up the hole and if its a precision hole a lapping tool will polish it up nicely.
Click to expand...

I do not think so , at least with this drill bits .Except that they are accurate 100% , also they drill perfect circle :thumbup:

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I think you are thinking of drill rod, not hole gauges. Drill rod is pretty cheap but usually comes in 36 inch sections so it is way more than you need, unless you bought a bunch, cut them up and sold sets of them, if there was a demand. But as mentioned above the shank of regular drills usually works fine.
 
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