The drill gets through the part, but the reamer starts picking up material. Or the first holes look good and the finish gets worse as production continues. It is tempting to add concentrate or turn up the coolant pressure. Before doing either, find out whether the cutting edge is receiving the right fluid, in the right condition, through the route the tool actually uses.
Oemeta NOVAMET 770 AE is a water-miscible coolant worth evaluating for demanding drilling and reaming, including suitable high-alloy steel, titanium and nickel-alloy applications. The trial should connect fluid chemistry, tool delivery, the condition of the drilled hole and the final inspection. A good product cannot clear a blocked passage, correct runout or remove more stock than a reamer was selected to cut.
Tech Tool carries Oemeta NOVAMET 770 AE in pail, drum and tote formats. This guide explains where it enters the discussion and gives your team a practical way to compare it. The aim is reliable accepted holes with less avoidable tool changing, rework and production interruption, measured against your existing process.
Where NOVAMET 770 AE fits
Oemeta's U.S. NOVAMET 770 AE description lists drilling, deep drilling, reaming, honing and other machining operations. It describes a mineral-oil-free, boron-free and formaldehyde-free formulation, with particular relevance to high-alloy steels, aluminum, titanium and nickel-based alloys. The manufacturer also highlights washing activity, corrosion protection and foam behavior.
Its recommended concentration is application-dependent. Get the current U.S. technical sheet, the correct measuring factor and a working range for the actual alloy and operation. The manufacturer's foam information mentions water hardness from 10 °dH; that is a condition attached to a product statement, not permission to treat any water supply or high-pressure circuit as suitable without checking it.
For the shop, the useful question is whether the fluid can support a repeatable holemaking process within the machine's requirements. Check the exact alloy and material condition, tool design, depth-to-diameter ratio, water quality and subsequent cleaning. Those details determine the trial. A broad aerospace or medical application description does not establish customer approval for a particular part.
Keep the exact name on the setup sheet and quote. NOVAMET 770 AE, NOVAMET 875 and NOVAMET 910 B are separate products. A concentration or correction factor used for one does not automatically belong to another. If the machine is currently running neat cutting oil, this is a fluid-system change requiring a separate machine and process review.
A drilled hole and a reamed hole are two different stages
Drilling makes the starting hole. Reaming removes a planned amount of material to produce the required size and finish. If the starting hole wanders, varies in size or arrives with damaged surface material, the finishing tool inherits that condition. More coolant cannot turn an unsuitable starting hole into the stock allowance the reamer needs.
Give the drilling and reaming stages separate records. Measure the drilled hole where the inspection method allows, then record the finished bore. Keep material condition, runout, alignment, tool wear and stock allowance with the results. An oversized finished hole can involve tool eccentricity or alignment; an undersized result can involve worn tooling or insufficient allowance as well as unsuitable fluid.
Allied Machine's reaming technical guide distinguishes these causes in its troubleshooting tables. Use the recommendations for the actual tool. The value of that distinction is practical: it helps avoid buying a new fluid to solve a geometry problem, or changing tools repeatedly when the fluid reaching the cut is the unresolved variable.
For nickel alloys, do not borrow a steel setup because the hole diameter is the same. Alloy and heat-treatment condition, tool geometry and the surface left by the preceding operation matter. Ask the tool supplier for the starting parameters and the stock allowance for that combination. Keep those settings stable while investigating fluid performance.
Pressure and flow answer different questions
Pressure is a useful signal, but it is not a measurement of how much fluid passes through the tool. Flow is the quantity delivered over time. A restricted passage can show a substantial upstream pressure while the cutting edge receives inadequate flow. The location of the measurement matters as much as the number on the display.
UNISIG's deep-hole drilling technical reference, updated February 2024, describes cutting-fluid flow as carrying chips and heat from the process and treats pressure as developing through flow restriction. The requirements vary with tooling type. A gundrill, BTA system and through-coolant twist drill do not have interchangeable fluid and chip-return paths.
Use the machine and tool instructions to identify where fluid enters, where chips return and which measurements represent the circuit. Record the tool installed, active outlets, filter condition, fluid temperature and test location. Ask maintenance to investigate a change in that circuit before attributing it to concentrate strength.
Do not adopt a universal pressure, flow or filter rating from an online table. The relevant target comes from the actual tool, holder and machine system. Test through the guarded procedure, and isolate the system before inspecting passages or connections. High-pressure lines are not something to open experimentally while the machine is running.
Match the fluid to the hole, not only the alloy name
| Detail | What to write down | What it helps resolve |
|---|---|---|
| Material | Exact alloy, condition, hardness where known and lot changes | Whether the proposed fluid and tool recommendations fit the work |
| Hole route | Diameter, depth, blind or through, entry condition and cross-holes | Fluid access, chip exit and the stages needing separate checks |
| Tools | Drill and reamer IDs, coating, coolant passages and wear endpoint | Which recommendations and comparable tool-life records apply |
| Starting hole | Measured size, variation, straightness where checked and reaming allowance | Whether the finishing tool is receiving the hole it was selected for |
| Fluid circuit | Delivery readings, measurement location, filtration and temperature | Whether a chemistry trial is being limited by the system |
| Fluid condition | Exact product, concentration method, water source and contamination results | Whether the charge matches the intended working condition |
| Finished result | Size, finish, geometry, cleanliness and applicable inspection method | Whether a tool-life improvement produces usable parts |
Use the worksheet for one repeat job first. If the machine alternates stainless steel and titanium, do not combine the results into one average without identifying the job. A fluid can look economical in the blended report while the more demanding operation still stops production. Keep the difficult stage visible.
Check concentration before changing concentration
A refractometer reading is useful only when the sample, instrument and product factor are right. Take a representative sample from circulating fluid using the shop's sampling procedure. Check the instrument with the appropriate reference, read the sample and apply the factor for the exact product. Record the measured reading and calculated concentration separately.
If the boundary is difficult to read or laboratory results disagree, investigate the sample condition and contamination. Adding concentrate to make a blurry reading move can overshoot the intended working range without solving the original problem. Where the result is uncertain, obtain a repeat sample or a supplier-selected test before adjusting.
Compare the measured condition with the range agreed for the trial. If it is outside that range, restore it through the supplier's mixing and adjustment procedure, then recheck after circulation. Keep the measured correction distinct from a decision to test a different concentration. Otherwise two different changes become one result nobody can interpret.
Do not assume higher concentration always gives a better hole. The formulation, water, foam behavior, residue and machine conditions have to work together. Ask for the trial range and the reason for it. Keep any subsequent change small enough to evaluate clearly and within the product and application instructions.
When the finish changes, separate the likely causes
| Observed change | First comparisons | Useful next record |
|---|---|---|
| Delivery changes during the run | Fluid level, filter condition, active circuits and temperature | Pressure and flow at the specified test point with the same tool installed |
| Reamed size shifts but drilling looks stable | Reamer wear, runout, alignment, stock allowance and measurement temperature | Starting-hole and finished-hole results tied to the same part lot |
| Material pickup on the cutting edge | Actual fluid condition and delivery, tool wear, cutting data and alloy condition | Tool photographs and wear observations at a repeatable endpoint |
| Chip clearing worsens at depth | Tool/chip return route, delivery, chip form and cutting parameters | Depth of onset and the tool supplier's recommended investigation |
| Foam appears after a circuit change | Air entry, fluid level, return turbulence, water and product concentration | Before/after circuit condition; avoid an unreviewed additive dose |
| Parts pass machining but fail cleaning or inspection | Cleaning route, residue, rinse and the applicable test method | Results after the normal downstream process, not only immediately off the machine |
Use these comparisons to select the next check, not to pronounce the cause from a single symptom. Rising load, changing chips and poor finish can come from several interacting variables. If the tool is failing unexpectedly or the process moves outside its operating limits, stop through the machine's procedure and inspect before another attempt.
Run the trial in a sequence that tells you something
- Choose the repeat job. Pick a demanding but controlled drilling-and-reaming route. Record its normal variation, inspection requirements and limiting operation.
- Record the existing result. Collect comparable accepted output, rejections, tool changes, fluid condition, delivery and interruptions. Keep drill and reamer endpoints separate.
- Review NOVAMET 770 AE for that route. Confirm current U.S. documents, material suitability, working concentration, water requirements, measuring method and machine compatibility.
- Plan the recharge. Agree cleaning, residual-fluid handling, mixing, circulation and restart checks. Record the new charge rather than treating an uncertain blend as a fresh-product trial.
- Verify the circuit and first parts. Confirm fluid condition and delivery through the actual tool route. Inspect the starting hole and finished bore before extending the run.
- Collect a comparable production period. Hold the main settings steady; record any necessary adjustment, filter change, tool replacement or material-lot change.
- Review the complete result. Compare accepted holes, tool cost, interruption time, fluid use and downstream cleaning. Extend to another job only after the first decision is clear.
A tool lasting longer is useful only if it produces holes that pass the required inspection. Define the wear endpoint and inspection frequency before the trial. Do not compare a baseline tool changed on a schedule with a candidate tool pushed to failure. If the production period ends before a tool reaches its endpoint, report it as an incomplete life comparison.
A hole-by-hole record can reveal what shift averages miss
For the first trial stage, number the parts or record a traceable production sequence. Track the drill and reamer used, holes completed, tool changes and the inspection points. Note where a finish problem begins within the hole or within the tool's life. That pattern can be more useful than a shift average that combines good and failing stages.
Record the reasons for stoppages separately: a planned inspection, a worn tool, chip clearing, a fluid adjustment or another machine fault. Include the clock time and minutes lost. When a trial claims fewer coolant-related interruptions, this record makes it possible to check which interruptions actually disappeared.
Use the shop's approved measuring method for diameter, finish and geometry. A plug gauge answers a different question from a bore measurement at several depths, and neither automatically establishes surface roughness. Choose the inspection that matches the drawing rather than adding a measurement only because it is easy to collect.
Keep the fluid sample and production record connected by date and machine. A sample taken after adjustment cannot establish what the tool was seeing during the failure. If that timing is unavoidable, label it and retain the earlier observations. The supplier then knows which condition was measured and which remains uncertain.
Calculate cost per accepted hole
Illustrative calculation, not a promised NOVAMET result: the baseline period produces 4,000 accepted holes. Tooling costs $480, fluid cost allocated to that period is $120, and recorded interruption cost is $300. The selected recurring costs total $900, or $0.225 per accepted hole.
Suppose a candidate period also produces 4,000 accepted holes, with $400 tooling, $150 fluid and $180 interruption cost. The total is $730, or $0.1825 per accepted hole. The difference is $170 for that measured period, or 4.25 cents per accepted hole. The higher fluid cost does not prevent an overall improvement in this hypothetical case.
This example is a partial cost comparison. Add actual material loss, rework, cleaning, inspection and other changed costs where they belong. Do not count the same interruption twice through a fully burdened machine rate and an overlapping labor allowance. For parts with several holes, show both holes accepted and parts accepted so one passing hole on a rejected component does not inflate the result.
Show one-time cleaning, recharge and disposal costs separately. If an actual repeat period saves $170 and the conversion costs $680, four comparable periods would recover that cost only if the measured improvement continues. That is an arithmetic scenario, not a payback promise. Repeat the calculation with your production mix before extending the change to more machines.
Cleaning and customer requirements belong in the trial
Check the normal washer, rinse and inspection route using trial parts. A clean-looking component at the machine can still carry fluid in a blind hole or threaded feature. Give the cleaning team the product identity and the features most likely to retain fluid, then compare their results under the existing process.
For aerospace, medical or other controlled work, check the drawing, purchase requirements and process instructions before conversion. Material compatibility in a product description does not replace a customer's fluid restrictions, cleanliness requirements or approval of a process change. Have the responsible quality team decide what evidence is needed for that part.
Obtain the current SDS and review handling and exposure controls as part of the change. Mineral-oil-free does not mean risk-free. Keep machine containment and the shop's fluid-management practices in the comparison. Product performance and safe operation are connected, but one good machining result does not establish the other.
Five takeaways for demanding drilling and reaming
- Evaluate NOVAMET 770 AE against the exact alloy, tool, hole route and current U.S. product instructions.
- Record the drilled hole and the reamed bore separately so the finishing tool's starting condition is visible.
- Check coolant flow and pressure through the actual circuit; a pump display alone does not establish tool delivery.
- Verify concentration with the product-specific measuring method before deciding to change it.
- Compare quality, tooling, interruptions and cleaning cost per accepted hole or accepted part.
Questions about NOVAMET 770 AE and holemaking
Is NOVAMET 770 AE suitable for nickel-alloy machining?
Oemeta's U.S. description identifies nickel-based alloys among its intended applications. The actual alloy condition, tool and hole route still need a product discussion and trial. Give Tech Tool that information so the recommendation addresses your operation rather than the material family alone.
What concentration should we use for deep drilling?
Use the range supplied for the exact product and application. Oemeta does not give one universal concentration on the public product page. Bring the alloy, tooling, water results and circuit details to the discussion, then record the agreed target and measuring factor on the setup sheet.
Will increasing coolant pressure fix chip packing?
It may not. Check the required flow, tool passages, return route, chip form and cutting data within the machine and tool instructions. A restriction, insufficient delivery or unsuitable chip shape needs its own response. Do not raise pressure beyond equipment limits to compensate for an unresolved problem.
Can the same coolant run the drilling and reaming stages?
It can be evaluated for both where the application and product instructions fit, but inspect both stages. The drill and reamer may have different delivery needs and wear behavior. Their shared fluid does not make one tool's successful result proof that the other operation is ready.
Can we judge the fluid from one good tool run?
One run can identify a promising direction. A purchasing decision needs comparable quality, wear and interruption records over enough production to reflect the job's normal variation. Keep incomplete tool-life results visible and confirm downstream cleaning before broadening the trial.
Give Tech Tool the details of the difficult hole
Send the alloy and condition, hole diameter and depth, drill and reamer IDs, current fluid, water information, delivery readings and the point where the result changes. Include the inspection requirement and normal cleaning route. Talk with Tech Tool about a NOVAMET 770 AE application review and quote. We can help start the product discussion with the current documents and a trial your machining, quality and purchasing teams can evaluate together.
