What Did You Do Today (2016)

[John Stevenson 1Participant @johnstevenson1]

Posted by Muzzer on 21/10/2016 17:56:54:

What I'd really love to see would be 2 mating segments of involute gears in some sort of CAD / animation where you can vary the radii in both polarities (ie concave and convex gears) and see how the tooth profiles change while remaining involute. I hope I'm not appearing to volunteer myself here, as I don't understand enough or have enough bandwidth to do it at the moment. It's interesting to see how the internal teeth shape differs from the external teeth in Andrew's illustration.

The internal shape differs as what was the addendum on a spur gear is now the dedendum of the internal gear.

Both values swap over. In Gearotic you can lay out this problem that Andrew has and animate it whilst playing "what if"

It is also possible to stub the gear and shift it to get either a stronger tooth form or one that doesn't interfer.

[DerilParticipant @deril]

An interesting project,

Helpful information for designing and making internal gears is included in booklet 4 (of 6) on gearing written by F. Whiteley and published in 1951 by the A.E.S.D.

Sixteen pages are devoted to the subject.

They open with :- "A most common error made in connection with the design of internal spur gears is to accept the rather misleading statement made in many text books that all dimensions for internal gears may be found by using the same formulae as those for external spur gears"

[Ed DuffnerParticipant @edduffner79357]

If the clouds clear I might have a go at photographing some of the Orionids during the night/morning. Should be most active at about 3.0AM I believe.

Ed.

[WindyParticipant @windy30762]

Have been told to keep out of the workshop and take things easy what a bugger.

On point of collapsing last Friday Doctor had numerous warnings of what was wrong due to medication.

At A & E anemia was the cause and had six units of blood transfused plus other things.

Good job I'd moved a job onto kitchen table before going to hospital I am a naughty boy but it's not the workshop.

In many ways the good side of the web is a Godsend in circumstances like this.

Been released from York Hospital I had to miss an achievements award for staff at the hospital who give that bit more.

A lass Helen Lickley who I nominated when in the cardiology earlier in the year Won a well deserved award.

I have so much admiration for the staff who work there and saw some of the stresses they have to endure from awkward patients but they act so professionally,

**LINK**

 

Edited By Windy on 21/10/2016 22:50:10

Edited By Windy on 21/10/2016 23:01:01

[Michael GilliganParticipant @michaelgilligan61133]

Take it steady, Windy

You've got records to beat.

MichaelG.

[Anonymous]

Posted by John Stevenson on 21/10/2016 20:09:14:

Both values swap over. In Gearotic you can lay out this problem that Andrew has and animate it whilst playing "what if"

Quite so; I got Gearotic to generate an internal gear and pinion last night, having loaded it onto the new computer. I also managed to generate a helical gear. And then everything disappeared; whatever I did I just got a blank canvas.

On a more practical note I took this afternoon off from working on the electronics for non-dispersive infrared sources and detectors and made the mating helical gear to my previous effort. For the gears to mate on parallel shafts the second gear needs to be lefthand rather than righthand. This involves swivelling the mill table in the opposite direction, and adding an idler gear to the gear train so that the dividing head rotates in the opposite direction. The idler gear can be clearly seen in the picture:

The setup was a right (or should that be left) faff. In order to maintain clearances I had to move the dividing head one set of T-slots over, move the cutter towards the overarm support and use my home made riser blocks so the division plate didn't clash with the table. Even then it was tricky to access the division plate to index the gear. It was made easier by having made the stop for the plunger on the division plate, so that I could lock it in the out position. That meant I was much less likely to accidentally move the indexing arms. All went well and the second gear appeared, on the left naturally:

They seem to mesh smoothly, and the centre to centre distance is as it should be, at least as measured with a rule.

Tomorrow the plan is to do some 3D printing of internal gears and pinions, and have a play with the gearing on the dividing head to explore low leads. Sunday will be admin, and then I'm afternoon tug pilot.

Andrew

[HopperParticipant @hopper]

Windy, take it easy, mate. And don't forget to leave room on that kitchen table to eat plenty of good food to keep your strength up for that project.

[Jeff DaymanParticipant @jeffdayman43397]

"Posted by Windy on 21/10/2016 22:48:52:

Have been told to keep out of the workshop and take things easy what a bugger.

On point of collapsing last Friday Doctor had numerous warnings of what was wrong due to medication.

At A & E anemia was the cause and had six units of blood transfused plus other things."

Hi Windy, get well soon. The anemia sounds like a job for black pudding and plenty of pints of stout! JD

[Paul LousickParticipant @paullousick59116]

My Seig SX3 mill has recently been having problems and the push-buttons would fail to work although the motor would continue to run at whatever speed it was previously set to. The only way to turn it off was to hit the emergency stop putton. Re-set stop button and everything would work as normal for a while.

I cleaned the electrical connections with CRC contact cleaner and all seemed good. Meanwhile Ausee Machine Tools had a sale on all products and I purchased a spare controller board as a spare. Today the problem returned and I replaced the old controller board, swapping one wire at a time from old to new board to keep track of where they go. With fingers crossed, turned it on and everything works.

When I removed the board from its mounting, 2 large electrolytic capacitor fell out and not being an electronics expert suspect that these were the cause of the problem. The wires had snapped at the base of the capacitors. I am surprised that the motor would still run with broken capacitor connections.

Paul.

[Nigel McBurney 1Participant @nigelmcburney1]

Andrew ,regards helical cutting on the A/S 2E,your photo shows your Elliott dividing head with the index plate facing towards the machine, not wishing to offend but I think your set up is wrong,your Elliot head should be set up on the right hand side of the table with the division plate facing you then its a lot easier to carry out indexing. Some manufacturers notably Cincinatti and Parkinson placed their dividing heads to the right hand side of the table. and looking at your Elliott head they must have done the same,though the Victoria machines which were aquired byElliott placed theirs to the left and the later heads were badged Elliott Victoria,your head is badged just as Elliott,so why they made a RH head I do not know.I learnt my milling on a 1950s Victoria universal,one regular job was a 10 tpi acme screw thread milled with a form cutter mounted in the rack cutting head, to get over the lack of a short lead attachment a pulley was mounted on the spindle which held the index plate and driven by v belt from a geared slow speed motor mounted on the left hand side of the table. Now there is mention that your adcock and Shipley 2E mill having different connections for the windings on the 2 speed main motor, I have the same mill powered via a rotary 3 phase converter and can only get the slow speed to work ,could it be that one of the two connections does not suit my converter which is 25 years old and was from the cheap end of the market at the time. Todays work well thats a magneto gear for a Ruston Hornsby engine and then a 63 T gear for a Harrison.

[Simon CollierParticipant @simoncollier74340]

Paul, my SX3 had to have the board replaced and also the touch panel which had broken up at the button positions. Now it won't reverse, and the handle-activated tapping function has not worked for years. I need a new main board, and as wiring it through to the head is a lot of work, I was quoted roughly $A1000. I basically really like the machine but it is hardly very reliable electronically.

[Anonymous]

Nigel: I've been waiting for somebody to tell me I've got the dividing head the wrong way round. Indeed it is, but that's the best I can do with the kit I've got. The dividing head manual shows both left and right hand heads, so presumably Elliott made both. Of course for conventional dividing I can put the dividing head on the right hand end of the table. But for spiral milling the pick off for the gears is on the left hand end of the table, like it or not. So I have to put up with it.

As far as I'm aware the 2E has a Dahlander motor which uses pole switching to achieve the two speed ranges. It also changes from star in high range to delta in low range, to minimise the loss of power due to halving the angular velocity, by rearranging the order of coils within the motor.

I'm not sure why there are two high/low switches on the machine. I assume that the electrical looking switch on the right, under the speed changing dials, is the main control for the spindle motor. But It's not clear what the tortoise/hare switch on the electrical panel does. When changing speed ranges I've always changed both.

Andrew

[BazyleParticipant @bazyle]

I'd say your dividing head is a less common one from all the ones I see on ebay. The K&T manual makes a feature of theirs being designed for right hand mounting for right hand use. But as most operators want a right hand handwheel the left hand one is often left off for driving the head in spiral mode so the head is made to fit on the left. So K&T put an extra shaft geared 1:1 on the right of some mill tables to drive their 'non standard' head.

[Anonymous]

Posted by Bazyle on 22/10/2016 12:15:45:

I'd say your dividing head is a less common one from all the ones I see on ebay.

Trust me to have the odd one; probably why it was cheap.

Andrew

[BazyleParticipant @bazyle]

Sunny and not much wind, put up ladders to check chimney coping, came in for a coffee and posted above. Went up chimney, all ok, and was going to have a moan about the 3 more wind turbines I could see from up there and the noise from my neighbour's chainsaw. Then noticed an ambulance going by. Figured the air ambulance would be along in a while if it was a problem up on the moor.. In fact I had only got to the bottom of the ladder when it circled me and came in to land. Seems that during my coffee break inside a rider had fallen off her horse just out of sight behind the trees but only concussed and eventually taken off in the wheeled ambulance. Last time they landed this close it was for a cyclist. It was not someone I know,being from the next village and her companion, holding the horses out of sight of the 'chopper said that only a couple of minutes after the fall a doctor and a dentist walking their dogs were on the scene so well looked after. We often collect for the air ambulance as small roads and congestion in holidays can make the trip to hospital a long one. It landed on the cricket pitch last year but found the gate was locked so had to lift the stretcher over.

[Nigel McBurney 1Participant @nigelmcburney1]

On my A/S 2E the tortoise /hare marked switch changes the speed of the table feed motor

[John RuddParticipant @johnrudd16576]

Put the finishing touches to installing my new mill…..

Added my new vice to the table….what a weight that is! Its only a 5 in vice too….

[Sam Longley 1Participant @samlongley1]

Interesting about the air ambulance. For 10 years I was the Clerk to the local committee looking after moorings in our river. At the end of each year we used to donate monies received for launching & recovering boats to the RNLI . However, our village is often referred to as " god's waiting room" & one year it was questioned as to whom we should make the donations. It was observed that RNLI came to our part of the river once every 2 months, whereas the the air ambulance came to our village once every couple of weeks. Guess who gets the money now!!!

[Anonymous]

Posted by Nigel McBurney 1 on 22/10/2016 15:22:46:

On my A/S 2E the tortoise /hare marked switch changes the speed of the table feed motor

Thanks Nigel, another mystery solved.

Now I just need to work out why, and how, the feedrates change by 3 to 2 from high to low whereas the spindle motor is 2 to 1, ie, 4 pole and 2 pole.

Andrew

[HOWARDTParticipant @howardt]

Just spent the last two weeks in New England, for the fall. Did a circular drive from Boston of 1300 miles. I can see how they can have such big workshops. When out of the cities houses each stand in a few acres. Sometimes the barn/garage is bigger than the house and often surrounded by rusting junk. No snow while I was there but was told it could be expected any time now, one petrol station I called into on the coast north of Boston actually had a guy pump gas for you, he said the norm was four/five feet there.

[Anonymous]

This morning I had a quick play with short leads on the dividing head, sure enough one can drive the table by turning the division plate instead of vice-versa. Then I dismantled the dividing head setup and gave the horizontal mill a good clean. The dividing head was transfered to the Bridgeport. I then made a number of spacers and adaptors for the spiral milling set ups. Finally the dividing head was set up on the Bridgeport along with the right angle head ready for milling a high helix (60&ordm helical gear. The lead is about 164mm; it's too much for the table drive, it just stalls. However, it is quite hard work turning everything from the division plate. So I may play with the gear parameters before committing to machining. The exercise is just to make a high helix angle gear, it doesn't matter much what the actual parameters are. The other issue is that the cutter is all over the place. I'm not sure if that's because it's a cheap cutter, or I have a problem with the right angle head and/or arbor. Investigation needed.

The other thing I did, or rather let it get on with it, was to 3D print an internal gear and pinion, as previously designed in 3D CAD:

The gears mesh very well, as indicated by the CAD system. This is quite encouraging as, while the pinion was downloaded, the internal gear is entirely my own design. The question now is do I make these gears, or do a quick redesign at 20ºPA and make the new gears?

Andrew

[IanTParticipant @iant]

What I did today was drill & tap a 8.2mm hole in the 'new' tool block for a 3/8th BSW thread, when the original tool post is 3/8th BSF. Obviously had my mind on other things… and only spotted it when I sat down with a coffee just now to assemble the parts and think about the next step…

Other words come to mind but 'Rugger' will have to do for now….

Never mind, done dafter things before and will no doubt do worse ones in the future… Start over or make a new tool post…think I will sleep on it.

Regards,

IanT

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Andrew Johnston on 22/10/2016 22:01:51:

The gears mesh very well, as indicated by the CAD system. This is quite encouraging as, while the pinion was downloaded, the internal gear is entirely my own design. The question now is do I make these gears, or do a quick redesign at 20ºPA and make the new gears?

.

Nice work, Andrew

To answer your question with a question: If these work [as, evidently, they do] … Why would you bother re-designing with 20° PA ?

MichaelG.

.

P.S. … This is probably 'too hard' for me, but you may find it interesting/useful:

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19830011874.pdf

 

 

Edited By Michael Gilligan on 22/10/2016 22:54:25

[Anonymous]

Posted by Michael Gilligan on 22/10/2016 22:37:45:

To answer your question with a question: If these work [as, evidently, they do] … Why would you bother re-designing with 20° PA ?

Because then I would be designing both gears from scratch. Then, if they work, I could say that I have at least a basic understanding of the design process.

Thanks for the link. I skimmed the article last night. There's some interesting maths on the problems of interference in internal gears, although they seem to use 'non-standard' terminology. Once I'm happy I can design and make a basic gear set I'll look at the interference problems in more detail.

It is interesting to note that the 3D printed gear set has an assembly issue. The gears mesh properly, but cannot be assembled properly by pushing them together in the same plane. Instead they need to be assembled axially. In reality when the 3D printed gears are assembled in the same plane they need a good push, and there is an audible click. I suspect that metal gears, with less 'give', wouldn't assemble.

Andrew

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Andrew Johnston on 23/10/2016 10:32:05:

It is interesting to note that the 3D printed gear set has an assembly issue. The gears mesh properly, but cannot be assembled properly by pushing them together in the same plane. Instead they need to be assembled axially. In reality when the 3D printed gears are assembled in the same plane they need a good push, and there is an audible click. I suspect that metal gears, with less 'give', wouldn't assemble.

.

Now, that is interesting

Keep up the good work

MichaelG.

[Author]

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