A Floating Chucking Reamer-Why not!

[Janderso]

Not quite the same, but very similar, my floating chamber reamer holder.......does this count?

here it is on the cover of Machinist Workshop magazine


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Heck yeah it qualifies.
IMHO anyway

 

[GeneT45]

Nice work @Janderso ! Now the real question: how do you best test its efficacy?

GsT

 

[pontiac428]

Nice work @Janderso ! Now the real question: how do you best test its efficacy?

GsT

The failure mode for reaming always results in a taper flaring at the bore entry. Check it with gauge plugs.

 

[LVLAaron]

I built one today. I used stuff I had around the shop, so the materials aren't ideal. I figured if I like this thing, I can remake any particular part. I used aluminum for the outer collar (mistake) Aluminum is VERY sticky when in contact with steel.

I found some 2 inch round bars of bearing bronze on ebay for a pretty fair price. I'll rebuild the collar if I like this tool.

I did make the mid/rocker plate out of 4140, and man do I hate working with that stuff. I did 4 reamed holes instead of slots. This was mainly because I didn't think far enough ahead with my work holding.

 

[extropic]

I built one today. I used stuff I had around the shop, so the materials aren't ideal. I figured if I like this thing, I can remake any particular part. I used aluminum for the outer collar (mistake) Aluminum is VERY sticky when in contact with steel.

I found some 2 inch round bars of bearing bronze on ebay for a pretty fair price. I'll rebuild the collar if I like this tool.

I did make the mid/rocker plate out of 4140, and man do I hate working with that stuff. I did 4 reamed holes instead of slots. This was mainly because I didn't think far enough ahead with my work holding.



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Nice work . . . except

The four holes in the midplate won't allow float in the same way that slots would.
When the torque is applied through the tool, the pins will contact their respective holes in a certain orientation and not be able to slide as they would along the planar wall of a slot. You may be able to feel the condition by holding both ends, one in each hand, applying and maintaining torque while trying to slide the two in opposite radial directions. The radial force required to overcome the "self-centering" effect of the torque will be quite high relative to the torque. By "self-centering" I don't mean that the chuck will be precisely coaxial with the shank. I mean it will want to be in the same (not floating) axis-to-axis orientation each time torque is applied. A perfect floating holder would have zero radial resistance regardless of the magnitude of torque.
I understand that it can be made to wobble, if the torque is low enough, but that's not the same as what is normally considered float.

You'll be much happier after you make a new mid-plate with slots.

 

[LVLAaron]

Sh&t. I didn't have to read past your first sentence to know what you're saying.

I will make a new one before I even test this one. Thank you!

 

[mmcmdl]

I'm lazy .

 

[Shotgun]

I'm lazy.
<shows five different tools he made to do the same thing.>.

LOL!!

 

[LVLAaron]

I have corrected my sins.

Still haven't used it in the lathe, but I can tell it works how it should.. It doesn't bind up when tightening it.

 

[extropic]

No sin. Just a learning experience.