Aixing Group Acquires Mantle to Develop Industrial 3D Printing in Tool Manufacturing
The Aixing Group acquisition of Mantle pushes hybrid metal additive manufacturing into injection mold tooling. This page explains what TrueShape does on the shop floor, which mold parts it suits, and when CNC machining still wins.
What this acquisition changes for mold builders
A consolidation story told from the machining side: what the technology does, what it costs you in process steps, and how to decide.
Why a molding group bought a metal AM startup
Tooling groups have been buying additive capacity for years, but mostly in the form of plastic printers and vacuum casting patterns. Metal tool inserts are a different animal. They run at 200–300 °C, see abrasive glass-filled resin, and get pulled apart for maintenance every few hundred thousand shots.
Mantle's TrueShape platform deposits metal paste layer by layer, then green-machines the part before sintering. The sintered blank comes out oversized and is finished on a CNC. So the machine that prints is not the machine that holds the tolerance. That last step is where the mold shop lives.
The commercial logic is straightforward. A group that owns molding plants, tool rooms, and CNC capacity can absorb a new process if it drops into the existing finishing workflow. A standalone AM startup cannot, because nobody wants a mold insert that still needs a wire EDM and a sinker after sintering.
- 1Paste extrusion, not powder bedLower thermal distortion than laser powder-bed fusion on thick sections.
- 2Green machining before sinterShrinkage is compensated in the soft state, so hard milling is reduced.
- 3CNC finishing after sinterFinal dimensions and surface finish come off a machining center.
TrueShape in process terms: print, green machine, sinter, finish
Think of it as a four-step chain rather than a printer. Deposition builds near-net geometry, including internal channels that a 3-axis mill cannot reach. The part is still soft and machinable at this stage, which is the key difference from powder-bed fusion.
Green machining sets the stock allowance for shrinkage. Typical linear shrinkage on sintered metal paste runs in the single digits as a percentage, so a 100 mm insert may grow or shrink by a few millimeters between green and sintered states. That number must be dialed in per alloy and per build orientation, and it is not a guess you want to make on a customer's mold.
Sintering brings the part to full density. Mantle publishes densities above 99.5% for its mold alloys, which matters because porosity in a tool steel insert shows up as a stain on the molded part after a few thousand shots. After sinter, the insert goes back on a machining center for datums, parting lines, and the cavity itself.
The finishing side is where a shop with 5-axis capacity adds value. Conformal cooling channels are printed. The boss that bolts to the mold base is machined. There is no reason to print a flat mounting face that a face mill can produce in 90 seconds at Ra 0.8 μm.
- 1PrintedNear-net cavity, conformal channels, deep ribs, and conformal venting.
- 2Green machinedDatum faces, shrinkage compensation, rough cavity form.
- 3SinteredDensity above 99.5%, hardness developed per alloy spec.
- 4FinishedParting lines, shutoffs, cavity polish, and fit to mold base.
Which mold parts suit hybrid AM and which stay on the mill
A rough filter for quoting. If a part scores on the left column, print it. If it scores on the right, machine it.
| Part / feature | Hybrid AM + CNC | CNC only |
|---|---|---|
| Conformal cooling channel | Curved channel following cavity form | Straight drilled lines only |
| Deep rib, aspect ratio > 6:1 | Printed rib, machined root | Needs EDM electrode |
| Flat insert under 150 mm | Overkill, print adds steps | Mill from 1.2343 block |
| Cavity with freeform 3D surface | Print near net, 5-axis finish | 5-axis from solid billet |
| High-gloss optical surface | Print then polish, risk of pores | Hard mill and polish |
| Insert with tight shutoff ±0.005 mm | Machined after sinter | Machined from solid |
| Low-volume bridge tool, 5,000 shots | Good fit, short lead time | Aluminum tool, faster still |
Where the process loses, and what to watch
Hybrid AM does not remove machining. It moves it. You still need a finishing cell, you still need a tool room that can hit ±0.005 mm, and you still need to inspect. A shop without that side already in place gains little from a printer.
Surface finish off the sintered blank is rough. Plan on leaving 0.3–0.5 mm on printed faces that will be visible in the cavity. Internal channel walls stay as-printed, so coolant flow and heat transfer depend on the as-built roughness, not on a polished surface.
Material choice is narrower than a mill. Mantle's platform targets mold and die steels, not the full 6061-to-Inconel range a machine shop carries. If your part is a copper-beryllium core pin or a 7075 aluminum prototype, this process is the wrong tool.
Cycle time claims are process-specific. Published figures compare printed conformal tooling against EDM-cut tooling, not against 3-axis milling of a simple insert. On a part with two straight cooling lines and no deep ribs, printing usually loses on cost and lead time.
- 1Finish allowanceLeave 0.3–0.5 mm on printed faces that need a polished cavity.
- 2Channel roughnessAs-printed internal walls affect flow more than channel diameter.
- 3Alloy rangeMold steels only. Aluminum and copper alloys stay on the mill.
- 4Volume filterSimple inserts under 150 mm rarely justify the extra steps.
How to write a drawing that survives both processes
Split the drawing into printed features and machined features, and tolerance them separately. Printed geometry gets a profile tolerance on the as-built channel path. Machined geometry keeps the ±0.005 mm callouts, the datum scheme, and the Ra values you would use on a solid insert.
Call out the datum faces that will be machined after sinter. If the print orientation puts the main mounting face at an angle to the build plate, the machined stock allowance becomes asymmetric and you burn time on the first setup.
For injection molds, note the resin and any glass or mineral filler. Abrasive fills drive gate and runner wear, which is a machining and heat-treatment question, not a printing one. Conformal cooling helps the cycle; it does not help wear.
If the tool is a bridge or low-volume tool, say so on the RFQ. The right answer may be an aluminum cavity machined in 3–5 days rather than a printed steel insert, and a shop that runs both processes can tell you which is cheaper before you commit.
Questions engineers ask after the announcement
Does hybrid metal AM replace CNC machining for mold inserts?
No. It adds a near-net forming step in front of machining. The printed part is oversized and soft, gets green machined, is sintered, then is finished on a machining center to final tolerance.
The CNC side still sets parting lines, shutoffs, datum faces, and cavity polish. Without that capability in-house, the printed insert is not a finished tool.
Which mold parts benefit most from conformal cooling?
Parts with hot spots that a straight drilled line cannot reach: deep cores, tall ribs, slides, and thick sections next to thin walls. Cycle time and warpage are the usual reasons to print.
A flat plate with two straight channels and a uniform wall sees little gain. Machining it from 1.2343 tool steel is faster and cheaper.
What tolerance can be held on a printed and machined insert?
The printed geometry carries a profile tolerance that depends on shrink compensation and build orientation. Machined features can be held to ±0.005 mm with a proper datum scheme.
In practice, design the print for near net and put all the tight callouts on faces you will cut after sintering. That keeps the process window comfortable.
How much stock should be left on printed surfaces?
For visible cavity faces, 0.3–0.5 mm is a practical starting allowance. That covers sinter distortion, green machining error, and enough material for a clean finishing pass.
Internal channel walls are not machined, so their roughness is whatever the print produces. If flow matters, specify the channel path and check it on the first article.
Can a shop without a printer still quote hybrid mold work?
Yes, if it has the finishing side. Printed inserts can be sourced and then machined, inspected, and assembled in-house. The value a machining partner adds is the last two steps, not the print.
The catch is communication. Shrink compensation, datum strategy, and stock allowance all have to be agreed before the build starts, because none of them can be fixed after sintering.
What materials does the platform cover?
It targets mold and die steels used for injection tooling. It does not cover the full metal range a machine shop stocks, such as aluminum alloys, copper alloys, titanium, or nickel superalloys.
If the part is an aluminum bridge tool, a beryllium copper core pin, or a 7075 prototype, plan on CNC machining from solid.
Send the tool drawing and we will tell you which process fits
Upload a 2D or 3D file and we will return a quote with a DFM note on printed versus machined features, within 12 hours.
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