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Reamers
- Thread starter Jonathans
- Start date
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- Jul 2, 2014
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Adjustable reamers of the multi blade type can get the job done, but they are delicate and get damaged easily, depending on type. Patience and care is required. They need to be sharpened correctly. You have to take tiny cuts with them, need to keep them in line with the bore, and need to stop instantly if they start to gall. The types like those used for reaming automotive king pin bushings are easier to use, the tapered pilot sleeve helps to keep the reamer aligned to the bores.
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- Jul 2, 2014
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The other issue is that you will almost certainly need a through hole to use an adjustable reamer.
I was thinking about the expandable to reach the next size up. One or two thousandth's over. etc.
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- Jul 2, 2014
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A couple thou is about all an adjustable reamer can usually do, at least in steel, without being a PITA. Don't get me wrong here, adjustable reamers can save the day, and get a job done that would otherwise have to wait until new tooling can arrive. They are just not too good for repetitive work, slow and fussy, or for trying to take .010" out of steel. A chucking reamer of the needed size will do a nice job in no time with little fuss.
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- Dec 27, 2014
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I have a product with two 5/16 bushings, 3/4" apart, I assemble the body with a 5/16 rod in place, remove it and run a 5/16 reamer through the hole Almost always there is a tiny bit of misalignment which the reamer takes out. I keep on hand a 5/16 adjustable reamer, probably .001 over, just in case the 5/16 reamer doesn't take enough out. Sometimes I have to open it up just a little. Noting precise in the job, not at all. This hole's shaft carries a gear with 80 teeth, the other a gear with 8. That gear, .300 in diameter is pinned to a 1/8 shaft. They have to turn without friction.
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- Jul 20, 2014
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Expandable reamers require great skill and excellent gages to measure. I have a vintage Cleveland USA set and it is not easy to get the hole on target.
(Probably why they don't make them anymore). They're OK for general use but not precision hole targets. They're also very tedious to use. Drill, ream, measure, expand, ream, etc..with careful measuring in between with a good mic and hole gages. Not my favorite way to go. Nothing like a good APT reamer and Criterion boring head.
(Probably why they don't make them anymore). They're OK for general use but not precision hole targets. They're also very tedious to use. Drill, ream, measure, expand, ream, etc..with careful measuring in between with a good mic and hole gages. Not my favorite way to go. Nothing like a good APT reamer and Criterion boring head.
- Joined
- Jul 2, 2014
- Messages
- 7,594
Good point, Emilio. If you pick up a .5000" reamer, and use it correctly, you will get a hole very close to that number, and a nice smooth bore. Using an adjustable reamer it a lot more hassle, and slower. Even with a chucking or hand reamer, it is a really good idea to check the size before boring the hole. Sometimes mistakes are made in labeling or testing, reamers get sharpened and can be smaller than labeled, and wear takes its toll as well. Still, it is much slower and fussier to get an accurate, well finished hole with an expansion reamer.
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