Core Bit Adapters & Accessories

World Diamond Source® engineers heavy-duty Core Bit Adapters & Accessories to maximize machinery compatibility and eliminate rigging bottlenecks on-site. Machined from premium, high-tensile structural steel, these universal conversion adapters allow contractors to seamlessly run our high-performance bits—as well as other alternative bit brands—across any major drill rig or power head connection on the market. Our high-demand inventory includes robust thread conversions between standard 5/8″-11 and 1-1/4″-7 connections, along with premium SDS-Plus and SDS-Max shank conversions for heavy-duty rotary hammers operating in spin-only modes. Designed to bridge the gap between any power source and your tooling, these deeply stocked accessories ensure your crew can confidently core through hard concrete with reinforcement with zero lead-time delays.

Frequently Asked Questions

What core drill adapters do you stock?

Adapters that bridge the common core drilling connections: 1-1/4"-7 male to Hilti® 3-keyway and 6-keyway, 5/8"-11 male to Hilti® 3-keyway and 6-keyway, 5/8"-11 male to 1-1/4"-7 female and the reverse, 5/8"-11 male to SDS Plus, and 5/8"-11 male to 1/2" and 3/8" shank. Between them they cover most rig-to-bit combinations crews run into.

Which adapter do I need for my drill?

Two things decide it: the thread or keyway on your machine and the thread on the bit. A 1-1/4"-7 bit on a 5/8"-11 machine needs the BSA-series step adapter; a Hilti® keyway machine needs the matching 3-keyway or 6-keyway adapter, and 3 and 6 keyway are not interchangeable. Count the keyways on your machine or call us at 800-611-8278 with the make and model and we will confirm before you order.

Can I run a core bit on a regular hammer drill?

For small diameters, yes, with the right adapter. We stock 5/8"-11 male to SDS Plus, and to 1/2" and 3/8" shank, so a 5/8"-11 bit will mount in a rotary hammer or a heavy drill chuck. Keep it to small bits: a hand drill has neither the torque nor the rigidity for large-diameter coring, and no water feed.

What extensions do you stock, and how do I use them?

6" and 12" core bit extensions in both 1-1/4"-7 and 5/8"-11 thread. They thread between the machine and the barrel to add depth past the bit's own length. Use the single longest extension that reaches, rather than stacking several, because every joint adds runout and makes the bit want to wander.

Will an adapter change how the bit drills?

It adds length and one more joint, so the assembly is slightly less rigid than a bit mounted straight to the rig. Ease off the feed pressure, keep the machine anchored solidly, make sure water is still reaching the crown, and never let the bit stall in the cut. A properly matched thread seats fully; if it does not, stop and check the adapter rather than forcing it.

Not sure which tool fits your machine? Call 800-611-8278 and we will confirm before you order.