When I first started handling purchasing for our shop, I assumed that buying our own machine was the only way to control quality. If we make parts in-house, I thought, we don't have to pray the supplier shows up on time.
Turns out, that assumption was half wrong.
I'm the office administrator for a 40-person manufacturing company. I process 60 to 80 POs a year and manage roughly $80,000 in orders across six vendors. I report to both operations and finance. I don't write CNC programs and I don't run a lathe. But I'm the one who signs the purchase order and then has to explain the expense. So this article isn't an engineer's technical comparison. It's a buyer's look at the decision you actually need to make: should you buy a used 3 axis CNC milling machine and tool it up with Sandvik Coromant products, or should you outsource the work to a large CNC turning services manufacturer?
The comparison that actually matters
The usual way to frame this is machine cost versus part price. That's too narrow. You also have to compare tooling, setup time, lead time, and the risk of a bad part sitting on your floor.
The question everyone asks is, 'What's the price of the machine?' The question they should ask is, 'What's the total cost of my first good part?'
That's where Sandvik Coromant enters the picture. If you're looking at Sandvik Coromant products, you're already thinking about tool quality, not just tool price. Good. That mindset makes you ready to compare these two options honestly.
Upfront cost: used 3 axis CNC milling machine vs. quoted parts
Let's start with the obvious. A used 3 axis CNC milling machine seems logical. Based on current used equipment listings I checked in February 2025 (MachineryTrader, Gindumac, and a few dealer sites), a decent used 3 axis CNC milling machine from a common brand runs somewhere between $15,000 and $60,000. Add rigging, installation, coolant, workholding, and training, and you can easily spend another $8,000 to $20,000 before you cut the first chip.
On the other side, a large CNC turning services manufacturer doesn't ask for a down payment. They quote a per-part or per-batch price. You don't see a six-figure line item, but you also don't own anything. You're buying a service, not a machine.
Conclusion: if you're comparing cash outlay alone, outsourcing looks cheaper. But that's not the whole story, because per-part cost depends heavily on tooling.
Tooling and per-part cost: where Sandvik Coromant products show up
Here's where many purchasing folks get weird. If you buy the used mill, you'll need toolholders, end mills, drills, and inserts. You can get no-name inserts at a fraction of the cost of Sandvik Coromant products. I've done that. When I took over purchasing in 2020, I found a great price on no-name inserts—$600 cheaper than our usual order. They couldn't provide proper documentation, but I ignored that because the price was good. The first few parts looked fine. Then the insert edge broke mid-cut, ruined a part, and cost us a night shift. The replacement insert didn't have the same cutting edge geometry. Surprise, surprise.
Sandvik Coromant isn't the cheap option. I won't pretend it is. But when I look at cost per finished part instead of cost per insert, the math changes. According to Sandvik Coromant's published technical catalog (sandvik.coromant.com, accessed February 2025), insert grades and geometries are matched to specific material groups. That sounds like marketing until you test it. A correct grade gives you predictable tool life. A generic grade gives you hope.
Also, check the logo. Actually, check the logo closely. When you buy genuine Sandvik Coromant products, the Sandvik Coromant logo is part of the packaging and is marked on most tool bodies. I once ordered what looked like a deal on CoroMill end mills, and the inserts didn't seat properly. The logo was slightly different, and the packaging said 'compatible' in tiny letters. We lost about $2,400 in scrapped parts before the quality team caught it. Now I verify before I buy.
If you outsource to a large CNC turning services manufacturer, you won't see their tooling invoice. The shop picks the tools based on their process. Some use Sandvik Coromant, others use different brands. It's okay to ask. A reputable shop will tell you what tooling standards they use. If they hesitate, that's a red flag.
Conclusion on this dimension: in-house, tooling is a visible cost you can control. Outsourced, tooling is buried in the part price. For small volumes, outsourcing often wins because you don't pay for a full tooling setup. For repeat production, investing in good tooling—including Sandvik Coromant products—can make the used CNC mill approach look better.
Lead time and flexibility
I used to think outsourcing always meant waiting. Sometimes it does. A large CNC turning services manufacturer has a queue. In Q3 2024, we ordered a batch of machined components from a contract manufacturer, and the quoted lead time was six weeks. It arrived in five and a half. That was fine for our production schedule, but it wouldn't work for a broken down machine.
In-house, we can cut a simple part same-day if the machine isn't already running. But a used 3 axis CNC milling machine is not always ready when you are. Our used mill needed a spindle bearing replacement two months after we bought it. That was a fun $4,200 invoice, and it was down for nine days. If you don't have a maintenance person on staff, downtime can eat your schedule.
Another nuance: a 3-axis mill can do many things, but it's not ideal for complex turned parts. That kind of work belongs on a CNC lathe or turn-mill center. A large CNC turning services manufacturer usually has both. So real flexibility depends on what geometry you need.
Conclusion: in-house is better for quick, simple, repeatable parts once the machine is running. Outsourcing is better for complex parts and for production that doesn't need to appear overnight.
The resin 3D printer question
Now let's address a question that comes up in every meeting about buying equipment: 'But what about 3D printing? How much are resin 3D printers?'
Short answer, based on current web listings from Elegoo, Anycubic, and Formlabs (February 2025): small resin printers are around $200 to $600, mid-range are $1,000 to $2,500, and bigger models run up to $4,000 or more. Verify current pricing because it changes quickly.
I understand why people ask. A resin 3D printer can make prototype parts overnight for a fraction of machining cost. But a resin printer doesn't cut metal. It doesn't hold the tolerances for most production parts. It's a fit-check tool, not a replacement for a used 3 axis CNC milling machine or a large CNC turning services manufacturer. I learned this the hard way when a 'prototype' made from resin was mistaken for an actual part and ended up on a test fixture. It failed in front of the customer. Not my finest moment.
Conclusion: 3D printing is a nice addition, but it's not the comparison here. If your parts require structural integrity, you still need a machining strategy.
Quality and consistency
Let's talk about quality. A used 3 axis CNC milling machine with Sandvik Coromant tooling and a skilled machinist can produce excellent parts. That's not the question. The question is: do you have that skilled machinist?
I've seen great operators make a $20,000 used machine work like a $200,000 one. I've also seen a cheap tooling setup turn a $20,000 machine into scrap. If you buy used, budget for tooling and for the person who knows how to use it. 'We'll learn along the way' is not a quality plan.
On the other side, a large CNC turning services manufacturer has process documentation, inspection reports, and repeatability. You're buying consistency, not just parts. For an admin buyer like me, consistency is worth a lot. I can defend one invoice from a qualified supplier. It's harder to defend scrapped parts and overtime.
Here's the unexpected conclusion: for most small shops, outsourcing to a large CNC turning services manufacturer is actually the smarter long-term move—even when buying a used machine looks cheaper on paper. The exception is if you already have a machinist and enough repeat volume. Then the in-house route with good tooling can win.
So what should you do?
- Buy the used 3 axis CNC milling machine if you have an experienced machinist on staff, a steady stream of simple milling work, and a willingness to buy genuine Sandvik Coromant products instead of the cheapest inserts.
- Outsource to a large CNC turning services manufacturer if you don't have a machinist, if your parts are complex or need specific certifications, or if your volume is low enough that setup costs don't amortize.
- Keep resin 3D printers in your toolset for prototypes and fit checks—but don't expect one to replace CNC machining.
And whether you buy used or outsource, keep the Sandvik Coromant logo high on your checklist. If you're buying tooling, verify the source. If you're evaluating a supplier, ask what they use. An informed customer asks better questions and makes faster decisions.
I'd rather spend 10 minutes explaining this comparison than watch another company buy a used machine and discover the hidden costs. Trust me, the hidden costs always show up.
