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Multi Purpose Drill Bits: What They Really Drill
What a multi purpose drill bit really drills, what it can't, and which size and length reaches through your wall.
Quick answer: A multi purpose drill bit is a carbide-tipped bit ground sharp like a metal drill. It drills through a stack of layers, such as tile over wood over brick, without a bit change. ITM, the maker of ours, rates it for six materials: ceramic tile, wood, plastic, mild steel, aluminum and brick. Porcelain, glass, poured concrete and stainless aren't on that list. Run it with hammer mode off. A 1/4 in. bit costs $6.43, or $29.94 for a five-size set.
What does a multi purpose drill bit actually drill?
A multi purpose drill bit drills the six materials its maker lists, plus anything softer. Nothing harder. The search results say more than that. Most answers online add concrete, porcelain and even glass. ITM's spec sheet for our BLU line doesn't. This table is the maker's list, plus what to use for the materials that didn't make it.
Material |
On ITM's list? |
How it goes |
If not, use |
|---|---|---|---|
Glazed ceramic wall tile |
Yes |
Rotation only. Put tape on the glaze so the tip doesn't skate. |
— |
Wood, plywood, OSB |
Yes |
Cuts, but slower and rougher than a wood bit. Expect tear-out where it exits. |
— |
Drywall and plaster |
Not by name, but softer than brick |
Easy. Back off at breakthrough so the paper doesn't tear. |
— |
Plastic and PVC |
Yes |
Light pressure, moderate speed, so the plastic doesn't melt and grab. |
— |
Mild steel: studs, boxes, strut, sheet |
Yes |
Slow speed with cutting oil. Fine for a few holes. For a run of holes in plate, an HSS bit is cheaper per hole. |
— |
Aluminum |
Yes |
Moderate speed with a drop of oil. |
— |
Brick and concrete block |
Yes |
Rotation only, firm steady pressure. Clear the dust every inch or so. |
— |
Porcelain tile, granite, quartz |
No |
Too hard for the carbide tip. It dulls in a hole or two. |
Diamond bit, such as HEX-26 (7/8 in., $18.53, min. 2) |
Glass and mirror (never tempered) |
No |
The sharp edge chips glass instead of grinding it. |
Spear glass bit, such as GD.375 (3/8 in., $6.38, min. 12) |
Poured concrete |
No |
Needs hammer action. Hammering cracks this tip. |
Hammer-drill bit, such as 700041664 (1/4 x 4 in., $2.93, min. 12) |
Stainless and hardened steel |
No |
Work-hardens under the heat the tip makes. |
Cobalt or carbide metal bit (see drill bits for metal) |
Material list from ITM's product specs for the BLU multi-purpose line, checked Oct 26, 2026.
Are multi-material drill bits any good?
Yes, when the hole crosses materials. They're a poor buy when it doesn't. The whole point is the stack: tile on a wood frame, a strap through siding into block, a box screw through drywall into a steel stud. A multi-purpose bit does those in one pass. With dedicated bits you'd need two or three bit changes.
You pay for that convenience. A 1/4 x 4 in. multi-purpose bit (BLU-1664) is $6.43. A 1/4 x 4 in. masonry bit is $2.93 (700041664), and a Cyclo Twist (F2504) is $2.49. So one multi-purpose bit costs what two or three masonry bits do. If every hole today is in the same block wall, buy the masonry bits.
Expect three habits. The tip can wander on glaze or bare steel until it bites. It leaves a rougher exit in wood than a wood bit does. And the carbide is hard but brittle, so a hidden rebar or a twisted drill can chip it.
Why do I have to turn hammer mode off?
Turn hammer mode off because the tip is ground sharp, and impact chips a sharp carbide edge. ITM rates these bits for rotation only, at moderate speed, with lubricant in metal. A regular drill works fine. A hammer drill works too, as long as the hammer is switched off. Hammering is also what cracks tile, so that setting protects the wall as well as the bit.
These are round-shank bits, so they go in a three-jaw chuck. They don't fit an impact driver's hex socket.
Which size and length do I need?
Pick the size by what goes in the hole, then the shortest length that reaches through every layer. Every bit in the line drills 1 in. less than its overall length. The 4 in. bits reach 3 in., and the 12 in. bits reach 11 in. So a 1/4 in. hole through 3/8 in. tile, 3/4 in. plywood and a 3-5/8 in. brick (about 4-3/4 in. in all) needs the 6 in. length.
SKU |
Size |
Overall length |
Drills up to |
Price per bit |
Minimum |
Common jobs |
|---|---|---|---|---|---|---|
1/8 in. |
2-1/2 in. |
1-1/2 in. |
$5.38 |
7 |
Pilot holes, small plastic plugs |
|
5/32 in. |
3 in. |
2 in. |
$5.67 |
7 |
3/16 in. masonry screws in brick or block |
|
3/16 in. |
3-1/2 in. |
2-1/2 in. |
$6.03 |
6 |
1/4 in. masonry screws, alarm contacts, cable clips |
|
3/16 in. |
6 in. |
5 in. |
$8.56 |
5 |
Fastening through tile and furring into block |
|
1/4 in. |
4 in. |
3 in. |
$6.43 |
6 |
Plastic anchors, low-voltage wire, strap screws |
|
1/4 in. |
6 in. |
5 in. |
$9.25 |
4 |
Tile, sheathing and brick in one pass |
|
1/4 in. |
10 in. |
9 in. |
$14.70 |
3 |
Through a brick veneer wall for a cable |
|
5/16 in. |
4 in. |
3 in. |
$7.19 |
5 |
Larger plastic plugs, coax |
|
5/16 in. |
10 in. |
9 in. |
$18.78 |
2 |
Coax or low-voltage through a wall |
|
3/8 in. |
4-1/2 in. |
3-1/2 in. |
$7.87 |
5 |
Recessed alarm contacts, larger anchors |
|
3/8 in. |
12 in. |
11 in. |
$20.48 |
2 |
Cable or tubing through brick, sheathing and a stud |
|
1/2 in. |
6 in. |
5 in. |
$10.76 |
4 |
1/2 in. PEX or small conduit through tile and block (1/2 in. chuck) |
|
1/2 in. |
12 in. |
11 in. |
$22.93 |
2 |
A line through a full exterior wall (1/2 in. chuck) |
|
5/8 in. |
6 in. |
5 in. |
$14.45 |
3 |
Supply lines and bundles; 1/2 in. reduced shank |
Prices and minimums from our catalog (PIM), Oct 26, 2026. Each bit is priced individually. The minimum is the fewest you can order of that size.
Need a little of everything? The BLU-SET5 is one each of 1/8, 5/32, 3/16, 1/4 and 3/8 in. for $29.94, with no minimums. Bought singly, the minimums would add up to 31 bits.
Who keeps a multi-purpose bit in the truck?
Anyone whose holes cross materials more often than they repeat. That's most service work.
Trade |
Typical stack |
Bit |
|---|---|---|
Electrical |
Box or strap screws through ceramic tile or drywall into block or a steel stud |
|
Plumbing |
Pipe straps and escutcheon anchors through ceramic tile into brick; small lines through a wall |
|
Glass & shower |
Clip and channel anchors in ceramic wall tile over backer board. Porcelain and glass go to diamond and spear bits. |
|
Alarm, low-voltage, telecom |
Contacts and cable through tile, trim, framing and brick veneer in one pass |
|
Homeowners and property maintenance |
Shelves, rails and fixtures on whatever wall is there |
For shower hinges and the tile holes behind them, follow our frameless shower door installation guide.
When should I switch to a dedicated bit?
Switch as soon as the hole is all one hard material, or a material off the maker's list. The common cases:
Porcelain or stone tile: a diamond bit. Our how to drill through tile guide has sizes and the 45° start.
Glass: a spear-point glass bit with water, and only on glass that isn't tempered.
Poured concrete: a carbide masonry bit with the hammer on. Browse masonry drills.
Stainless, or a dozen holes in steel plate: a cobalt or HSS bit. See how to choose drill bits for metal.
For the full map of bit types, see Types of Drill Bits Explained.
From the shop floor
"The smartest drill kit isn’t the biggest one. It’s one multi-purpose carbide bit for the everyday materials (tile, wood, plastic, mild steel, aluminum, brick) plus four specialists for the materials that won’t compromise: porcelain, glass, poured concrete and stainless."
David Castro, President, Eldorado Tools
FAQ
Is there a universal drill bit?
No single bit drills everything. A multi-purpose carbide bit comes closest: it drills ceramic tile, wood, plastic, mild steel, aluminum and brick. Porcelain, glass, poured concrete and stainless each still need their own bit.
Can a multi-purpose drill bit drill concrete?
Not well. Ours are rated for brick and concrete block with the hammer off. Poured concrete needs hammer action, and hammering chips the sharp tip, so use a masonry or SDS bit there.
What size multi-purpose bit for a Tapcon screw?
Use 5/32 in. (BLU-1064) for 3/16 in. masonry screws and 3/16 in. (BLU-1264) for 1/4 in. screws, in brick or block. Drill at least 1/2 in. deeper than the screw will go.
Can I use a multi-purpose bit in an impact driver?
Not ours. The BLU bits have round shanks for a three-jaw chuck, and they're rated for rotation without impact.
Can a multi-purpose bit drill porcelain tile?
No. Porcelain is harder than the carbide tip can cut for long. Use a diamond bit such as the HEX-26.
Not sure which length reaches? Call our team at (833) 4-ETOOLS or email sales@eldoradotools.com with what the wall is made of.
Sources: ITM product specifications for the BLU multi-purpose carbide line; Eldorado Tools catalog prices and minimums, Oct 26, 2026; ITW Tapcon published pilot-hole sizes.
First published [date], with prices checked in our catalog on Oct 26, 2026.
