A Floating Chucking Reamer-Why not!

[Janderso]

I was fortunate to receive a set of plans from Nigel. He has a Youtube channel, Go Create.
I'm sure most of you have seen this video. He does beautiful work.
I spent $300 for the 4130 needed to complete the project.
Yes, I could probably buy a Chinese copy for less but what the heck.
This will be a heck of a challenge for me. Isn't that what it's all about?

I should add, the aluminum Bronze he used for the outer ring would cost about $500 in material. I won't be using the same material

 

[woodchucker]

I would like to have one. That's a lot of $$$ in raw material. It doesn't look like it should be that much.

I'll have to check out the video tomorrow.

 

[woodchucker]

I wonder if you can use 1144 stress proof easy to work with

 

[Janderso]

I would like to have one. That's a lot of $$$ in raw material. It doesn't look like it should be that much.

I'll have to check out the video tomorrow.

He says to use 4130 or equivalent. I don’t know what equivalent means.
I mounted an MT3 taper in my chuck, dial indicated to zero. Cut the taper and it’s off?
I used scrap material. I need to cut two perfect tapers so I best figure it out. I’m already scratching my head

 

[Nutfarmer]

Jeff. I have some extra 4140 2. 1/2 bar stock you are welcome to.

 

[woodchucker]

just got back from my meeting and had a chance to watch the video. I was always under the impression that a floating reamer holder was one that didn't tilt, but moved in the y and z orientation to help align. in other words it remained horizontal, but it would move off center the slight amount necessary to center up on the hole.

I guess my understanding was incorrect.

 

[C-Bag]

i think it’s ironic to do so much precision to end up with a sloppy chuck Very interesting project. I wonder if I get the same effect with my floating vise in my tapping machine. I used it for the first time to finish ream a 5/32“ hole. It was a through hole so I wasn’t able to do like he did to to see if it was air tight but it sure came out nice.

 

[extropic]

<snip
I mounted an MT3 taper in my chuck, dial indicated to zero. Cut the taper and it’s off?
I used scrap material. I need to cut two perfect tapers so I best figure it out. I’m already scratching my head

A common issue is that the cutter MUST contact the workpiece at precisely the same height as the indicator that set the compound (from the reference taper). If the indicator contacted the reference taper any amount above or below the horizontal center plane, and the cutter is on the center plane, the cut taper will be off.
Take extreme care to get both at the same height. Using a drop indicator with a flat tip makes it easier to contact the reference taper tangent to the horizontal center plane than using a DTI or other indicator with a spherical contact.

 

[woodchucker]

I'm going to go out on a limb and say the plan for this is incorrect. I watched another video from the guy in NZ who used those plans. I was able to see clearly that the pins only allowed the tap to swing at the tip, they were too tight a placement so the reamer could not float off center and have the whole reamer stay centered, only the tip.

So in my view the plan should allow for room to travel on those pins, not just re-align the tip. The reamer or even a tap since it can be used for tapping, should float into alignment all the way, not just a tip swing on a radius.

I'm pretty sure that the OLD vintage ones I saw did not align only at the tip.

 

[Janderso]

A common issue is that the cutter MUST contact the workpiece at precisely the same height as the indicator that set the compound

Bingo. I didn't know this.

Taking some measurements this morning I also found my finish pass was too much. I didn't give myself a chance. I'm off by 003 at the "diameter end" the thickest part. I should be .938 but I'm at .935"

Thank you. I'll try, try again