Bronze, phosphor or otherwise, won't be a strong as steel, but should be plenty strong and tough. It's also more expensive, but provides good bearing surfaces for parts that rub or slide against one another. It's probably going to be pretty, too!?
I probably missed where you mentioned that. I'm spending a lot of my time sleep deprived, and frequently interrupted in my reading.?
Bill in OKC?
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY!
Expect in one hand, expectorate in the other. See which one gets full first.
On Wednesday, May 8, 2024 at 11:34:17 PM CDT, John Lindo <bechetboat@...> wrote:
Thanks Bill.
The ring scroll and pinions I will eventually use phosphor bronze, sorry if I did not make this clear, aluminium I am using for form fit and function only, plus cost and reduced time to machine
Cheers
John
On Thu, 9 May 2024 at 01:26, Bill in OKC too via <wmrmeyers= [email protected]> wrote: Forgings are not accurate enough for a precision tool. It's got to be properly machined and tough enough to withstand the forces applied.
If you really want this chuck to last, I'd suggest the pinion be good tool steel. Aluminum won't be tough enough. And it galls easily.?
Bill in OKC?
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY!
Expect in one hand, expectorate in the other. See which one gets full first.
On Wednesday, May 8, 2024 at 03:04:00 PM CDT, John Lindo < bechetboat@...> wrote:
Mike I thought that they may be drop forged, but there are definite score lines of a cutter drag ? or maybe they could be broached ? A female pot broach, and the pinion blank pushed from the top.? Then hardened and cylindrical ground. Provided I use the full diameter of the gear cutter, IE protruding the blank pinion to be cut out of the indexing collet sufficiently so at the end of the X axis travel the cutter does not hit the ER serrated clamping ring, I may get away with it. The indexer head will need?to be twisted 20 degrees to the X axis so then the depth of the cut along the pinion teeth? will stay the same I think. LOL?? I will let you know soon.? musical instrument repairs are getting in the way of this fun conundrum at the moment. Cheers John
I think the " Pinions " are forged in a manufactured chuck .
animal
On 5/8/24 1:00 AM, John Lindo wrote:
Struggling a bit with the 9 tooth pinion gear cutting.
I have only a Mod 2 12-13 T gear cutter.
My problem being as i move the cutter into the blank pinion, the
teeth wall between the teeth decreases, in fact they are looking
like a wedge
and will not mesh with the scroll gear teeth. see photo of the
parts marked 2 3?
The reason I think is even though I have twisted the indexer to 20
deg. (40 degrees inclusive angle) as the cutter?
moves in then the cutting diameter changes, the cutter dia is a
standard 58 mm, the teeth are only 12 mm long.
I think the the original pinion teeth of a chuck bought from a
tool supplier see photo marked 1 were hobbed, or a special smaller
dia gear cutter was used.
There may be several ways around my problem, (a) to make a fly
cutter tip with the involute form, thus greatly reducing the
cutter circumference,
the other option is (b) to CNC cut, When the X axis moves along
the 12 mm then the? Y axis? will move out 4.386 mm, keeping the
point of contact of the cutter circumference constant. I have also
machined on the lathe new pinion blanks, making them longer as the
other current problem being the cutter hits the collet locking
ring even though I am hanging the blanks out of the collet as far
as I dare. Once finished with the gear cutting, the blanks will be
parted off to length and a square milled in for the chuck key.
Photo shows marked 4, a double ended pinion blank, extra long for
the collet holder to avoid the cutter hitting the serrated ring.
   
marked as 2 , a aluminium proto before I attack LOL the phosphor
bronze, already scrapped one piece, it was to short anyway.
Any advise on how to get around this, then always welcome.
?
--
John
-- John
--
John
|
Bill in OKC too