Elliott 10M Spur Gear Shaping Attachment

[RobCox]

Here we go... final tooth being cut of a 26 tooth, 16DP gear in aluminium. The whole 135 thou depth was cut in one pass:

And the finished article:

To me, the teeth don't look deep enough, Not sure what I did wrong there.

And secondly, the last tooth being cut on the first pass of a steel gear, same tooth count and DP. This was much more unpleasant. The video doesn't seem to have picked up all of the grumbling from the shaper drive train. In hindsight, 3 passes would have been kinder to the machine, but it was slow. 2 minutes plus faffing per tooth (faffing includes trying to video it. Gives me an appreciation of the effort some of our esteemed members go to to post interesting content week in week out)

And the final result, steel beneath, ally above:

A few other bits of info. Setting up the toolbit vertically:

Highly sophisticated marker on top of the ways to indicate where to rewind to (yup, gaffer tape):

I used a clamp to indicate where to stop the cut, set after the first tooth was cut full depth and the tool was no longer touching the workpiece. Sorry for the blurriness:

Thats all folks!

 

[Pete.]

Here we go... final tooth being cut of a 26 tooth, 16DP gear in aluminium. The whole 135 thou depth was cut in one pass:

And the finished article:

View attachment 327916

To me, the teeth don't look deep enough, Not sure what I did wrong there.

And secondly, the last tooth being cut on the first pass of a steel gear, same tooth count and DP. This was much more unpleasant. The video doesn't seem to have picked up all of the grumbling from the shaper drive train. In hindsight, 3 passes would have been kinder to the machine, but it was slow. 2 minutes plus faffing per tooth (faffing includes trying to video it. Gives me an appreciation of the effort some of our esteemed members go to to post interesting content week in week out)

And the final result, steel beneath, ally above:

View attachment 327917

I thought that they looked a bit 'stub form' but you have decent bevel on the outside edge and that always makes the teeth look shallow. Try keeping the bevel one side and facing of the opposite side to get rid of it and compare how they apparently mesh with totally flat faces.

 

[ronan]

I cut some more gears today with the shaper. The first in aluminium and the second in horrid mild steel.

Aluminium is easy, full depth tooth in one go. Steel, hmm. I'd like to see someone cut a steel gear on a shaper with the wire and disc technique! The forces were much higher. I did the first tooth full depth. That exercised the sphincter somewhat. On the second tooth, the block that adjusts the stroke of the shaper vibrated loose. First time thats ever happened to me! I backed off to cut 90thou depth first time round and finished to 135thou on the second pass.

I counted the strokes needed to cut a 16DP tooth... 120! It took well over an hour to cut the steel gear.

Pictures and (landscape!) video to follow later.

Well if you are in a hurry, then a shaper is not the machine you head for. They are obsolete for a reason.

 

[prepman]

I cut some more gears today with the shaper. The first in aluminium and the second in horrid mild steel.

Aluminium is easy, full depth tooth in one go. Steel, hmm. I'd like to see someone cut a steel gear on a shaper with the wire and disc technique! The forces were much higher. I did the first tooth full depth. That exercised the sphincter somewhat. On the second tooth, the block that adjusts the stroke of the shaper vibrated loose. First time thats ever happened to me! I backed off to cut 90thou depth first time round and finished to 135thou on the second pass.

I counted the strokes needed to cut a 16DP tooth... 120! It took well over an hour to cut the steel gear.

Pictures and (landscape!) video to follow later.

The block on my Elliot shaper does that occassionally. It's a pig to get at through the little door and tighten, nothing to oppose the tightening action. The adjustment is fairly primitive. On the big Cincinnati shapers they have leadscrew style adjustments.
Have you to tried cast iron blanks? I'm not really a gear person, tend to opt out and use pulleys on the very few occasions I've needed ratio change.

 

[MattF]

They are obsolete for a reason.

A shaper is an obsolete piece of kit I would make room in my workshop for. I'd love to drop on a small shaper.

 

[prepman]

I cut some more gears today with the shaper. The first in aluminium and the second in horrid mild steel.

Aluminium is easy, full depth tooth in one go. Steel, hmm. I'd like to see someone cut a steel gear on a shaper with the wire and disc technique! The forces were much higher. I did the first tooth full depth. That exercised the sphincter somewhat. On the second tooth, the block that adjusts the stroke of the shaper vibrated loose. First time thats ever happened to me! I backed off to cut 90thou depth first time round and finished to 135thou on the second pass.

I counted the strokes needed to cut a 16DP tooth... 120! It took well over an hour to cut the steel gear.

Pictures and (landscape!) video to follow later.

Looking at gear cutting on net and came across this. Notice that it is still a reciprocating action similar to shaper and looks to be using the same procedure? http://www.gearcutting.com/

 

[prepman]

A shaper is an obsolete piece of kit I would make room in my workshop for. I'd love to drop on a small shaper.

And that's where the Hobbyists (Wombles) come in. If it came to a toss up between miller and shaper then the miller would go first.

 

[Hopefuldave]

I was watching Andysmachines doing that, using an ardweirdo.

Only negative is needing proper pitched hobs (the right DP/Module), although non-pitched hobs can be used if the Z axis can be controlled and timed too - I think that's getting into full CNC though :/

IF (Big If) you can cut Diametral Pitch (or Module) pitches on the lathe, the hobs are makeable (with some thought...) - I need to get a pair of 50-tooth, one 51-tooth (or 56 and 61 for Module) 16DP 20PA gears to cut those pitches first, of course...

Dave H. (the other one)

 

[Pete.]

I'm not following what you mean by non-pitched hobs Dave. You gotta use the correct hob for the gear's DP or module. There's a couple you can fudge like 20DP/1.25 mod if it's not critical. 50DP/0.5 MOd is also very close you can barely distinguish them without a microscope or shadowgraph.

 

[gaz1]

 

[ronan]

Getting a bit far fetched isn't it, if you cannot get a gear cutter or hob, or make one, then what sort of gear is it ? Time to forget it and pick up the gear catalogue.

HPC Gears: MANUFACTURER AND STOCKIST OF GEAR TRANSMISSION PRODUCTS

MANUFACTURER AND STOCKIST OF GEAR TRANSMISSION AND ENGINEERING PRODUCTS

www.hpcgears.com

 

[prepman]

Today...The thing I like about the shaper is I can produce this with a simple 8mm lathe tool. The dovetail is a doddle using angled top feed. Don't need dovetail cutters for the miller. Might be a bit too chunky, but not finished yet. Piece of spare bar stock MS. Better fit than the ones that came with the QCTP.

 

[Pete.]

Getting a bit far fetched isn't it, if you cannot get a gear cutter or hob, or make one, then what sort of gear is it ? Time to forget it and pick up the gear catalogue.

HPC Gears: MANUFACTURER AND STOCKIST OF GEAR TRANSMISSION PRODUCTS

MANUFACTURER AND STOCKIST OF GEAR TRANSMISSION AND ENGINEERING PRODUCTS

www.hpcgears.com

Trouble is you can't buy 14.5PA gears from HPC they only make 20PA

 

[RobCox]

Last time I looked at the price of an off the shelf gear (not the cheapest supplier no doubt) it was about the same as the cost of a cutter plus material. My time (for me) is free, so I end up with the gear I want plus a cutter if I ever need another one.

Admittedly cheapo chinesium cutters, but as I'm not building F1 gearboxes, good enough for my purposes.

However, with the shaper doodad the tooling's got cheaper too.

 

[ronan]

Trouble is you can't buy 14.5PA gears from HPC they only make 20PA

The Americans use a different pressure angle to this side of the pond, its less than 20PA, 14.5 ?

 

[Pete.]

The Americans use a different pressure angle to this side of the pond, its less than 20PA, 14.5 ?

Nowt to do with thaat, some gears are 14.5, others 20. 14.5 is 'older'. The 14.5 gears run more smoothly but the 20PA ones are stronger.

 

[ronan]

Trouble is you can't buy 14.5PA gears from HPC they only make 20PA

Nowt to do with thaat, some gears are 14.5, others 20. 14.5 is 'older'. The 14.5 gears run more smoothly but the 20PA ones are stronger.

 

[Richiew]

I paid 22 quid for a gear cutter for my slip rollers. I couldn't buy the gear I needed for the price as imperial isn't fashionable. I made two so I was probably quids in plus I learned a skill and had a lovely time too. I got some likes on here too.

 

[Richiew]

Here we go... final tooth being cut of a 26 tooth, 16DP gear in aluminium. The whole 135 thou depth was cut in one pass:



Thats all folks!

Hi Rob,

I'm a bit stupid so when you said you had cut the full depth in one pass I was a bit amazed then I watched the video and realised what you meant full depth as the machine turned into the cut bit by bit.

In my defence I've only cut gears with a horizontal mill before and if I attempted a full depth cut I'd probably be in hospital again with a bent spindle or torn out mill table.

 

[prepman]

I paid 22 quid for a gear cutter for my slip rollers. I couldn't buy the gear I needed for the price as imperial isn't fashionable. I made two so I was probably quids in plus I learned a skill and had a lovely time too. I got some likes on here too.

Any pics of the gear cutter? Do you mean hob? Interesting.