Sharpening Operations Continued
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Drill bit point over- | 1. | Adjusting block set too low. | 1. | Regrind bit in front and rear areas, but do not lower | |||||
split | and | chisel | 2. | Adjusting block not secured; blocks sags, |
| adjusting block so much. | |||
edges |
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| allowing wheel to grind bit too much. | 2. | Secure adjusting block before grinding. | ||
removed. |
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Amount | of | back | 1. | Adjusting block not low enough. | 1. | Lower adjusting block more (Page 18). | |||
relief ground into bit |
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is too small. |
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Heavy grinding nois- | 1. | Too much pressure applied on drill bit dur- | 1. | Use less pressure (Page 15) and take longer to | |||||
es. Drill | bit | smokes |
| ing grinding. |
| grind the bit. | |||
or tip has a black, | 2. | Tip is too hot and may have been softened | 2. | Try using the bit. If it dulls quickly the tip was soft- | |||||
blue, or purple hue. |
| too much. |
| ened. | |||||
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Standard | drill | bit | 1. | Bit has no back relief grind. | 1. | Follow instructions for grinding a back relief to | |||
point |
| skips |
| or |
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| improve drill bit performance (Page 14). | |
does | not | cut into | 2. | Heel is higher than cutting lip or is curved | 2. | Regrind the point angle until it is correct. If the heel | |||
workpiece. |
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| up. |
| is curved up, follow instructions for grinding a back | ||
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| relief. |
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Notch |
| on |
| collet | 1. | Point angle on bit may be different from | 1. | Select a point angle that matches or is closer to the | |
holder will not fit into |
| angle set on front grinding area. |
| existing drill bit point angle. Continue grinding the | |||||
grinding area flange |
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| point angle (if between 118° and 135°) until the old | |||||
edge. |
| Bit | retains |
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| angle is removed. | |||||
unground | material |
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or part of prior angle |
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after grinding in front |
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area. |
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Back | relief | ground | 1. | Adjusting block center point not directly over | 1. | Set center of adjusting block over edge of grinding | |||
into opposite cutting |
| grinding wheel edge. |
| wheel (Page 18). | |||||
edge. |
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Bits smoke or burn | 1. | The grinding wheel is dull. | 1. | Disconnect power and replace the grinding wheel | |||||
consistently | or | it |
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takes a much lon- |
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ger time to grind the |
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point angle or back |
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relief than normal. |
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H8203 Professional Drill Sharpening Machine |