Skip to content
From Cutting Tool Engineering

When full-diameter steel slotting is the only option

ProvenCut recipe 551 shows how to achieve a high material removal rate while maintaining a reliable cut.

June 15, 2020By John Saunders

Full-diameter slotting is not the preferred method for removing large amounts of material, but sometimes part geometry makes slotting the best — or only — option. ProvenCut recipe 551 shows how to achieve a high material removal rate while maintaining a reliable cut using a light-duty machine with a 6.35 mm (0.25″) endmill to slot 4140 alloy steel.

When developing this slotting recipe, we adjusted the spindle speed, feed rate and DOC with the goal of creating a dependable, productive process. We discovered that maximizing the DOC did not maximize the MRR. Rather, the recipe that achieved the best balance of removal rate and reliability was at a 6.35 mm axial DOC (Ap). The result was an MRR of 15,403.84 mm3/min. (0.94 in.3/min.). Our initial hypothesis that a larger axial engagement would lead to a higher MRR was wrong. Reducing the Ap from 200% to 100% allowed an increase in the feed rate that resulted in a 30% higher MRR.

When full-diameter steel slotting is the only option

Two notable differences between the 6.35 mm and 12.7 mm (0.5″) axial DOCs are enhanced chip evacuation and the number of radial contact points that an endmill has with the workpiece material. A 6.35 mm axial DOC results in one contact point with the material and produces one chip at a time, whereas a 12.7 mm DOC has two contact points and produces two chips at a time.

More points of contact can help stabilize a tool when using adaptive-style machining strategies with thin radial engagement, also known as dynamic or high-speed machining, but additional points tack on tool pressure. Too many points of contact can increase pressure to the level of causing chatter. With a light-duty machine, reducing points of contact helps minimize the amount of rigidity required for a stable, chatter-free cut.

Finish task to continue reading

Review the print ads from this magazine to continue

This quick advertiser review unlocks the rest of the article and keeps the full-screen reader focused on the ads instead of the page chrome.

Advertisers included in this article experience

Print placements connected to this article

Bluco.Com

HOLD IT A Modular Fixturing System Doesn’t

Cost Money - IT MAKES MONEY. Get your setup done in less than half the time with a modular base plate paired with a kit of precision fixturing components. Our fixtures can be assembled in minutes, not hours or days like outdated manual setups. Show us what you need to get done, and we’ll help you hold onto your parts — and your profits

HOLD IT A Modular Fixturing System Doesn’t Cost Money - IT MAKES MONEY. Get your setup done in less than half the time with a modular base plate paired with a kit of precision fixturing components. Our fixtures can be assembled in minutes, not hours or days like outdated manual setups. Show us what you need to get done, and we’ll help you hold onto your parts — and your profits. Call 800.535.0135 for solutions BLUCO.COM

Print page 17

Visit Bluco.Com View this placement in the issue record

The 6.35 mm DOC offered superior chip evacuation when compared with the 12.7 mm DOC. This improvement minimizes re-cutting of chips and enables coolant to more easily flush chips, reducing heat buildup and lubricating the cut.

Caution must be exercised when testing slotting recipes as the length of the overall slot and changes in slot direction affect the ability of coolant to access the cut. Any changes in a coolant’s aim can lead to tool failure and breakage — often quickly. A 102 mm (4″) test slot along one axis is very different from a 508 mm (20″) slot around the profile of a part that involves x- and y-axis movement.

Consider recipe 551 for drilling and tapping machines, Bridgeport-size machines or even old vertical machining centers that may not benefit from the higher rpm common with modern machine tools. A larger machine tool with more rigidity or power may yield different results.


To view a video of the slotting operation at www.ctemag.com, scan the QR code with your smartphone or enter this URL on your web browser: cteplus.delivr.com/2n4xt

Companion Media

QR codes and videos from this issue

Print QR codes, video callouts, and in-magazine links for this article now point to the CTE video hub in the HTML version.

June 2020 · Magazine page 1
Open CTE Videos
QR code for the CTE video hub Scan to open CTE videos
MFGAxis MFGAxis Discussion Be part of the shop-floor conversation Like, save, or comment on this CTE story.
Be the first to engage.

MFGAxis Discussion

Be the first to engage.
Scroll for the next article