UNISIG designs and manufactures precision deep hole drilling machines, gundrilling machines, BTA machines, tools and automation systems in the USA — from sub-millimeter medical drilling to 500 mm diameter holes over 10 meters deep.
Founded in 1981, UNISIG is a US manufacturer of deep hole drilling machines, tools and automation, with production in the USA and installations in the Americas, Europe and Asia. According to the company, it is one of the largest producers of deep hole drilling machines in the world.
Our industry-leading customers around the world rely on UNISIG deep hole drilling technologies for powerful, productive solutions and value. We engineer our machines to handle a complete range of applications, and support them with our high level of expertise and service.
Company information is based on UNISIG Deep Hole Drilling Systems's public website and was last reviewed on 2026-08-10. Verify specifications directly with the supplier before purchase.
| Attribute | Detail |
|---|---|
| Machine types | Full-range deep hole drilling machines: UNE6/UNE compact gundrilling machines, UNI production gundrilling/BTA machines (single and multi-spindle), B-Series BTA machines for on-center drilling of round workpieces, S-Series skiving and roller burnishing machines, USK off-center table-type gundrilling machines, UNX off-center cylindrical machines, USC-M 5-axis milling and drilling centers, USC large-capacity BTA and USC-TS multi-spindle tube sheet machines, UNR reaming machines, R-Series rifling machines and custom/extended-range machines. |
| Brands | UNISIG |
| Bore range | Under 1 mm to 500 mm (0.040–20 in) |
| Max drilling depth | Up to 10 m (30 ft) and longer; 12 m+ possible in larger diameters |
| Processes | gun-drilling, bta, skiving |
| Workpiece materials | Titanium, Carbon steel, Nickel alloy, 300M alloy steel |
| Applications | Aerospace (e.g., commercial aircraft landing gear struts), Medical (surgical tooling, bone drill holemaking after Swiss turning), Firearms (rifle barrel blank gundrilling, reaming, rifling; rifle receivers), Hydraulic cylinders (skiving and roller burnishing), Mold making (milling and deep hole drilling in one setup), Oil and gas, Energy (heat exchanger tube sheets), Automotive, Job shops (add gundrilling capability) |
| Certifications | ISO · DIN · AGMA · CE |
| Certification | Certificate no. | Issuer | Verify |
|---|---|---|---|
| ISO | — | — | — |
| DIN | — | — | — |
| AGMA | — | — | — |
| CE | — | — | — |
Quality evidence
Compliance
Aerospace · Automotive · Energy · Firearms · Hydraulic Cylinders · Job Shops · Medical · Mold · Defense · Oil and Gas
BTA drilling of profiled center holes in commercial aircraft landing gear struts (9 in [230 mm] diameter, over 7 ft [2.1 m] deep) in 300M alloy steel
UNISIG B700 Drop Bed machine with counter-rotating part and tool became an integral part of the production cell, delivering a reliable process meeting strict straightness and tolerance requirements
Gundrilling extremely small bone drill holes (up to 0.25 in [6 mm], depth-to-diameter approaching 100:1) after turning
UNE6 gundrilling machine with 20,000 rpm integral spindle and 3,000 psi high-pressure coolant; cycle time cut in half, running 2 shifts, handling 2 product families with over 30 part numbers
Skiving and roller burnishing of hydraulic cylinders across over 700 unique cylinder models
Initial purchase of six S600C machines (bores up to 200 mm, 3,000 mm long) installed in the USA and Mexico, reaching unprecedented surface finish levels
Combined milling, BTA drilling and gundrilling of mold tooling in a single setup
Purchased 2 USC-M38 machines initially, then added a third identical machine to support increased throughput and win more bids
High-volume gundrilling of rifle receivers using indexable gundrills (0.53–2.00 in [13.5–50 mm])
UNI25HD 4-spindle automated cell replaced several decades-old machines, achieving over 100 parts per hour (4–6x previous production) and eliminating a bottleneck while freeing floor space
Named reference customers
Alta Precision · ConMed
Installed base: Installations in the Americas, Europe and Asia
Trade shows
Contact UNISIG directly for pricing, specifications and delivery.
Steve Landmann — Vice President of Sales
Galbiati Group (Italy) is a manufacturer of horizontal multi-spindle deep hole drilling machines for shell and tube heat exchanger tube plates, with 1 to 5 spindles and BTA (STS) and gundrilling systems.
View profile →HTT Maschinen GmbH offers deep hole drilling machines for a drilling range from Ø1 mm to Ø800 mm and drilling depth up to 15,000 mm — BTA, gun drilling, multi-spindle and vertical solutions, certified to ISO 9001:2015 and CE.
View profile →Kays Engineering manufactures the Eldorado, DeHoff and TechniDrill brands of deep hole drilling machines, including gundrilling and BTA/STS systems — all designed and built in Marshall, Missouri, USA.
View profile →Mollart Engineering is a deep hole drilling machine manufacturer offering gun drilling and BTA drilling machines for precise holes in medical, automotive, aerospace and biomass applications.
View profile →The depth to diameter ratio is the determining factor, but 40 ft (12 m) and longer is possible in larger diameters with a machine designed for such an application.
Gundrills are available down to 0.5 mm (0.020 in). Mainstream applications for small diameter drilling are between 1.5 mm and 3 mm (0.06–0.12 in).
Neither — it depends on the application. Gundrills are typically employed between 0.8 and 50 mm (0.03–2.0 in), while BTA drilling is typical for 13–300 mm holes (0.5–12.0 in).