edited by Bernard Martin

Lexington Cutter has a put together a short checklist of the five most common problems for addressing reaming problems.  If these don't fix your particular problem, get in contact with us and we'll send one of our application specialist in to give you a hand.

1) Poor Finish

Possible Causes – Unequal chamfers, Incorrect margins, Excessive spindle runout, Chatter
Possible Solutions – Regrind reamer with equal chamfer angle. Regrind reamer with narrow margins for reaming lower tensile materials. Increase reamer back taper (will lose size faster). Reduce speed and increase feed rate. Use power feed unless material is hard. Use right or left spiral fluted reamer. Grind secondary lead angle immediately back of 45° chamfer.

2) Oversize Hole - Taper Hole - Bell Mouth Hole - Poor Finish

Possible Causes – Misalignment, Insufficient, cutting action
Possible Solutions – Use bushing – .0002″/.0003″ over reamer diameter. If hole location varies, use floating reamer holder. Increase reamer back taper (will lose size faster). Specify reamer with positive radial rake to reduce cutting pressure – may produce slightly larger diameter holes.

3) Excessive Tool Wear

Possible Causes – Insufficient stock for removal, Excessive reaming pressure, Misalignment
Possible Solutions – Decrease previous operation drill size to allow more material for removal by reamer – leave about 3% of hole diameter for cast iron and more stock for non-ferrous materials. Increase feed rate. Reduce stock to be removed by increasing previous operation drill size – leave about 3% of the hole diameter. See Problem #2

4) Crooked Holes

Possible Causes – Not drilled straight
Possible Solutions – Correct previous drilling operation – reamer will follow the drilled hole. Increase reamer attack angle (chamfer) to 120°/180° included angle.

5) Tool Breakage

Possible Causes – Excessive reaming pressure, Misalignment
Possible Solutions – Reduce stock to be removed – See Problem #3 – See Problem #2

Our last post about Lexington Cutter Offers h6 Shank Reamers prompted some questions regarding  what exactly is an"h" tolerance, so this post should help you understand it a bit more.
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Click the link below for a Shftt Tolerance Calculator.

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Cutting Tools are not exactly cheap.  One of the best ways to get extended life out of your milling cutters is to have them re-tipped or re-sharpened.  This can usually be done at a fraction of the cost of the original cutter and is much quicker than making a new cutter from scratch.  It can bring the cutter back to its original or acceptable specs.  Lexington Cutter re-tips and re-sharpens a lot of cutters including the cutters we use in our shop to make the tools we sell.  

Re-sharpening is exactly what the name implies.  Re-sharpening the cutting edges to remove imperfections generated during the cutters normal use. Care must be taken to minimize the amount of stock removal so not to undersize the cutter beyond an acceptable range and to allow for a greater number of future re-sharpenings.  Depending on the condition of the cutters re-sharpening may include sharpening the OD, sharpening the width, or face lapping.

Re-tipping involves taking the old pieces of carbide off, brazing on new pieces of carbide, and re-sharpening.  This typically brings the cutter back to its original specs.
Re-sharpening is slightly cheaper than re-tipping as there is less work involved and no carbide costs.
In order to be re-tipped or re-sharpened the existing cutters need to be in good shape.  The steel backing behind the teeth has to be in-tact.  The tools cannot be bent.  The hub on arbor hole style tools shouldn’t be too beat up (although this can sometimes be fixed by regrinding the hub).  The arbor hole should not be damaged excessively. 
  
As long as the operator is conscious of the fact that the cutters are going to be re-tipped or re-sharpened keeping the tools in decent shape is not a problem.  It is important to have enough existing cutters on-hand so the tools can be switched out before being run beyond the point of repair.  Too often we receive tools that are beyond the point of repair. But, we also have several customers on a re-tipping program that are very good about keeping their cutters in a repairable condition and regularly send them back to us for this service.

One advantage to using carbide tipped cutters over solid carbide or high speed steel cutters is the fact that they can be re-tipped.  Once solid carbide or HSS cutters have worn down beyond an acceptable range, that is the end of their life.  Carbide tipped cutters can be re-tipped as many as 3 or 4 times greatly extending the tool life beyond that of solid carbide or HSS cutters.
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Super Tool can typically turn around re-tipped or re-sharpened cutters in 1-2 weeks which is much shorter than making them from scratch.   We can re-tip or re-sharpen special cutters and we can re-tip or re-sharpen standard cutters.

Re-tipping does have its limitations.  In order to remove the carbide tips the teeth have to be heated up.  To put on new carbide the teeth are heated again.  This constant heating of the steel eventually changes the molecular structure of the steel making it weaker.  This is liable to happen after 4 or more re-tips which is why we limit the number of re-tips to 3 or 4.

Call: (440) 463-3970 or email: dmb@brownesales for more information on re-tipping or re-sharpening your carbide tipped cutters

In January of this year we welcomed a new member to our Browne & Co. sales team and with manufacturing companies opening up again, it's about time we introduce you to Jeff Terrace!

Just before joining Browne & Co in January 2019, Jeff worked at Hoffmann Group, a German cutting tool, hand tool, workstation and storage solutions manufacturer.

Jeff has been working as an InovaTool representative since February of 2019 and recently joined Browne & Company at the beginning of 2020 as our Cutting Tool Specialist. Please send Jeff and email or give him a call to introduce yourself or pick his brain about an application question.

Lexington Cutter, Inc. is excited to present our new Precision Coolant Chucking Reamers with h6 shank tolerances. At Lexington we strive to stay ahead of the competition in technology, product advancement, manufacturing processes, pricing, and delivery.

Lexington's new flyer continues to provide competitive pricing throughout the market. Lexington's commitment continues to provide you with superior products that will keep you a cut ahead of the competition.
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Listed below are some features of the new reamer:

• • .0002” TIR on Shank & Cutting Diameters when checked between centers; this is 60% better than our standard reamers
  • Tighter tolerance on cutting diameter +.0002"-.0000" standard
  • Increased flute capacity for better chip removal
  • Shorter overall length for maximum rigidity and repeatability
  • Available in metric shank diameters
  • Designed for use in Precision Holders such as Shrink Fit, Hydraulic Chucks
  • Superior performance in Precision Collet Chucks

Lexington Cutter, Inc. is excited to present their new Precision Coolant Chucking Reamers with h6 shank tolerances.  Lexington Cutter strives to stay ahead of the competition in technology, product advancement, manufacturing processes, pricing, and delivery.

Their new flyer continues to provide competitive pricing throughout the market. Lexington Cutter's commitment continues to provide you with superior products that will keep you a cut ahead of the competition.
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Listed below are some features of the new reamer:

• .0002” TIR on Shank & Cutting Diameters when checked between centers; this is 60% better than our standard reamers
• Tighter tolerance on cutting diameter +.0002"-.0000" standard
• Increased flute capacity for better chip removal
• Shorter overall length for maximum rigidity and repeatability
• Available in metric shank diameters
• Designed for use in Precision Holders such as Shrink Fit, Hydraulic Chucks
• Superior performance in Precision Collet Chucks

Give us a call at Browne & Co and we'll get you all of the details! 

Lexington Cutter proudly accepted the 2007 American Eagle Award for Value Added Manufacture at the 2007 ISA Conference and Trade Show in Las Vegas.

This prestigious award was presented as a result of the dramatic cost savings documented to Briggs and Stratton’s Alabama plant.

Lexington Cutter’s Vice President of Sales Junita St Esprit and Vice President of Technical Services Jim Trammell were invited by Jason Mathis of Max Tool to evaluate an application at Briggs and Stratton. The goal was to reduce tooling cost in a project that used custom carbide step drills on large runs of cast iron flywheels.

Lexington Cutter designed a custom carbide tipped step drill that was priced nearly 50 percent lower than the previous drill used by Briggs and Stratton, but achieved 10 times the performance. The tool produced 11,000 parts per tool, compared to just 1,100 parts for the tool it replaced.

The previous tool generated a tooling cost of $0.454 per part, compared to just $0.0262 per part for the new tool, for a total monthly savings of $12,850.