Part Type
Custom Machined Fittings
The adapter the catalog stops one size short of.
Custom machined fittings are turned and milled adapters for fluid and air systems: AN flare, ORB, NPT, hose barb, bulkhead, and cam-lock fittings cut to your print when the catalog stops one size or one thread short. They get made from 6061 aluminum, 303/304 stainless, brass, or titanium, with threads cut to gauge and sealing faces held tight so they actually seal. Send a STEP file and a PDF through the quote form and a real person sends back price, material, and lead time in 24-48 hours, with no minimum order.
Updated June 2026
The fittings that get turned to print
Most custom fittings start on a lathe as round bar and pick up their threads, flares, and seats from there. The common ones: AN/JIC 37° flare adapters in the standard sizes (-4, -6, -8, -10, -12), SAE ORB (O-ring boss) adapters, NPT adapters and reducers, and straight hose barbs sized to a specific hose ID. From there it goes to the odd stuff that has no part number: an AN-to-ORB adapter with a length nobody stocks, an NPT-to-metric reducer, a barb with a restrictor orifice drilled through it.
Bigger fittings add a milling step for wrench flats, hex bodies, or mounting features. Bulkhead fittings get a longer body and a matching bulkhead nut so the fitting can pass through a panel or tank wall and lock on both sides. Cam-lock (cam-and-groove) couplers, banjo fittings, unions, reducers, and weld nipples all fall in the same bucket: a known style, made to a thread or length the shelf does not carry.
Threads and seals that have to be right
A fitting is only as good as how it seals, so the thread and seal callout is where the print earns its keep. ORB and AN flare seal on a controlled face or O-ring, so those seats get held tight; tapered NPT seals on thread interference, which is a different animal and needs the right taper, not just the right size. JIC and AN look alike at 37° but are not always interchangeable, so name which one you mean. Spell out AN size (-4 through -12), thread (UNF, NPT, BSPP, or metric port), and whether a port is ORB or tapered.
O-ring grooves are their own callout: groove diameter, width, and depth drive whether the O-ring actually seals or extrudes, so those come off the print at ±0.002 in. Wrench flats or a hex want a size that fits a real wrench. If a fitting meters flow, give the orifice diameter and the tolerance that matters. When a detail is missing, the team asks before cutting rather than guessing, which is the whole point of a real-person 24-48 hour quote.
Materials for fluid and air
6061 aluminum is the default for automotive and motorsport fittings: light, strong enough for most fuel, oil, and coolant lines, and it anodizes in red, blue, black, or clear to match a build and add corrosion resistance. 303/304 stainless steps up for strength, high pressure, and corrosive media. Brass is the plumbing standard for water and low-pressure air and seals well on tapered threads. Titanium shows up where weight is the whole point and the budget allows it.
Material also drives the seal strategy. Aluminum and stainless ORB and AN fittings lean on O-rings and controlled flare faces; brass NPT leans on tapered thread plus sealant. Tell the team the media (fuel, oil, coolant, water, air, hydraulic fluid), the working pressure, and the temperature, and the material and seal style follow from there.
When custom beats off-the-shelf
Custom wins the moment the catalog stops one size or one thread short. The usual triggers: an odd thread-to-thread adapter no distributor lists, a bulkhead that needs to be longer or shorter than stock to clear a panel, a hose barb with a non-standard ID for a specific line, a restrictor orifice built into the fitting, or a run anodized to match the rest of an engine bay. These are the everyday reasons a fitting gets made to print instead of bought.
Every fitting is quoted, made, inspected, and shipped, from a single adapter to a production batch, with no minimum order. Common buyers are automotive and motorsport builds and energy and cleantech fluid systems, where one missing adapter holds up the whole assembly. Send what you have, even a sketch or the old fitting, and the quote names the rest.
Questions
Before you send a job.
01 Can you make a fitting that adapts one thread to another?
Yes, thread-to-thread adapters are everyday work: AN-to-ORB, NPT-to-metric, BSPP-to-AN, and the odd combinations no distributor stocks. Name the thread and seal type on each end (AN size, NPT, ORB, BSPP, or metric port) and the team cuts each to gauge. Quotes come back in 24-48 hours.
02 What is the difference between AN, JIC, and ORB fittings?
AN and JIC both use a 37° flare seat and look alike, but they come from different standards and are not always interchangeable, so name which one you mean. ORB (SAE O-ring boss) seals with an O-ring against a machined boss face instead of a flare, which holds higher pressure with less re-torque. Tell the team the size and seal type and the print gets cut to match.
03 What material should a custom fitting be?
6061 aluminum is the default for automotive and motorsport fuel, oil, and coolant fittings, and it anodizes for color and corrosion resistance. Use 303/304 stainless for high pressure or corrosive media, brass for water and low-pressure air plumbing, and titanium when weight is critical. Tell the team the media, pressure, and temperature and the material follows.
04 Can you make a bulkhead fitting with the nut?
Yes. Bulkhead fittings get a longer body sized to your panel or tank-wall thickness, plus a matching bulkhead nut so the fitting locks on both sides. Give the wall thickness it has to pass through and the thread and seal on each port, and both pieces get made and inspected together.
05 Do you machine cam-lock and hose-barb fittings to a specific size?
Yes. Cam-lock (cam-and-groove) couplers get made to the size and style you call out, and hose barbs get turned to a specific hose ID with the barb profile and thread you need. For barbs, give the hose ID and the line pressure so the barb count and retention are right. Odd or non-standard sizes are exactly what custom is for.
Get Started
Send us your files.
We’ll take it from there.
A quote in 24-48 hours, no minimums. Like the quote, and we’ll make your parts and ship them to you.
Get a Quote