Reaming Problem Solving

Posted: 17th April 2012 by brednane1981 in Reaming, Super Tool
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S 84 85 SOLID CARB_cpiThe first problem and probably one of the most common reaming problems is Poor Finish.  Possible causes include unequal chamfers, incorrect margins, excessive spindle runout, chatter, and insufficient cutting action.  Below is a table with possible solutions for each of the possible causes of poor finish:

Possible Causes Possible Solutions
Unequal Chamfers Regrind the reamer with equal chamfer heights.
Incorrect Margins Regrind the reamer with narrower margins for reaming higher tensile materials.
Excessive Spindle Runout Use bushings that are .0002″/.0003″ over the reamer’s diameter.
Chatter Increase feed and reduce the speed rate.
Use power feed unless the material being reamed is hard.
Use a spiral fluted reamer.
Grind a secondary lead angle directly behind the 45° chamfer.
Insufficient Cutting Action Use a reamer with positive radial rake to reduce the cutting pressure.  This may produce slightly larger diameter holes.

Another common reaming problem is the shape of the reamed hole including Oversized Holes, Tapered Holes, and Bell Mouth Holes.  Possible causes include misalignment and using the incorrect feed and/or speed.  Below is a table with possible solutions for each of the possible causes of Oversized Holes, Tapered Holes, and Bell Mouth Holes:

Possible Causes Possible Solutions
Misalignment Check fixturing & setup for possible causes; use floating tool
holder if necessary. Consider using precision bushings or piloted reamers.
Incorrect feed and/or speed rate Verify correct feeds and speeds.
See previous post Reaming Speeds and Feeds.

Another common reaming problem is Excessive Tool Wear.  Possible causes include improper amount of stock removal, excessive reaming pressure, and misalignment.  Below is a table with possible solutions for each of the possible causes of Excessive Tool Wear:

 

Possible Causes Possible Solutions
Improper Amount of Stock Removal Change pre-ream hole size to leave 2 to 3% of tool diameter.  See previous post Pre-Ream Hole Size.
Excessive Reaming Pressure Decrease feed rate. See previous post Reaming Speeds and Feeds.
Change pre-ream hole size to leave 2 to 3% of tool diameter.  See previous post Pre-Ream Hole Size.
Misalignment Check fixturing & setup for possible causes; use floating tool holder if necessary. Consider using precision bushings or piloted reamers.

Another common reaming problem is Crooked Holes.  The most likely culprit here is the drill walking or incorrect sharpening of the reamer.  Below is a table with solutions for the possible causes of Crooked Holes:

Possible Causes Possible Solutions
Drill Walking Correct the drilling operation.  A reamer will follow the drilled hole.
Incorrect sharpening of the reamer Increase the 90° included chamfer angle to 120° – 180°

Another common reaming problem is Tool Breakage.  Below is a table with solutions for the possible causes of Tool Breakage:

Possible Causes Possible Solutions
Excessive Reaming Pressure Decrease feed rate. See previous post Reaming Speeds and Feeds.
Change pre-ream hole size to leave 2 to 3% of tool diameter.  See previous post Pre-Ream Hole Size.
Misalignment Check fixturing & setup for possible causes; use floating tool holder if necessary. Consider using precision bushings or piloted reamers.

I’ve addressed the most common problems encountered while reaming but this post by no means addresses them all.  If you are having issues reaming please leave us a comment here or drop us a line on Super Tool’s Contact Us page.  We are happy to help.

Bryan Enander
Super Tool, Inc.
941-751-9677

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  1. PRAVEEN says:

    i have doubt regarding how to solution to be seen ocular line mark issue ,shall i increased rpm or increased feed please revert back as soon as possible

  2. miah says:

    HI

    I have a left hand spiral flute Reamer and i want to know that i only have a hand drill so what torque setting should my dewalt be set to. i have the problem that bits start coming of the side of the reamer then it is no use to me and it is expensive to replace. i am drilling through hole.
    i am doing the drilling in forward gear is that correct.
    thanks for your help

    • brednane1981 says:

      Even though we recommend using our tools in precision equipment all of the same parameters would still hold true in a hand drill. Shoot for 2-3% stock removal I would aim more toward the low side with a hand drill and try to mimic the speeds and feeds for the appropriate material. Torque should be set at a maximum and no stopping and starting or reversing in the hole. That is probably what is causing the chipping. Here is a link to our reaming speeds and feeds chart: http://www.supertoolinc.com/uploads/ReamingFeedsandSpeeds.pdf.

  3. Nikunj Hingrajiya says:

    hello sir,
    I am student of last year mechanical engineering. i want to know about which types of inspection done on the reamer tool and which instruments are use for inspection. this is helpful for my final year project. please help me regarding this.

    Hope for your positive reply..

  4. brednane1981 says:

    Hey Nikunj,

    Sorry for getting back to you so late. As part of our quality policy, we require a first piece inspection on every job that goes through our shop. This allows us to make sure that all our tools are being made to spec and maintain our output of quality tools. This process also allows us to address any problems that may occur during each step of production, and, if a problem is discovered, we can catch it on the first piece and correct it, without having to scrap out an entire job. All tools go through a final complete inspection before they are shipped out or placed into inventory. This is applied to every job that is run through our shop, regardless of what particular tool it is.

    As for reamers specifically, we use a variety of measuring tools during the inspection process. Below is a basic breakdown of what tool we use to measure the reamers’ specs:

    Diameter and Back Taper – Micrometers
    Core (flute root), Overall Length, Length of Cut/Flute – Calipers
    Circular Margin and Axial Rake – Optical Comparators
    Spiral (if any) – Machine Settings

    I hope this helps, and if you have any other questions please feel free to ask.

    Thanks
    Chadd Brown
    Super Tool, Inc.