Yep, thats what I did too.---Thanks
Kerzel a'la Tel
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tel
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Well I haven't been completely idle over the Christmas break - here's where I'm up to now.
It's getting a bit busy in there already, so, like Brian, I have more or less decided to move the points to the 'off' side, not least because then I can arrange for independent adjustment of the exhaust and spark timing.
Unlike Brian, tho', I have decided to incorporate a second set of timing gears so I can get back to a spark per cycle. With this in mind I cut a second set of gears today.
It's getting a bit busy in there already, so, like Brian, I have more or less decided to move the points to the 'off' side, not least because then I can arrange for independent adjustment of the exhaust and spark timing.
Unlike Brian, tho', I have decided to incorporate a second set of timing gears so I can get back to a spark per cycle. With this in mind I cut a second set of gears today.
Tel---I think you are doing an outstanding job on the Kerzel engine. As you have seen, mine does run, but not yet the way I want it to. I am very happy with the engine as a "total package", and many of the troubles I've had are more the result of my "amateur machinist" abilities, rather than any basic flaw in the engine design. I give you my best wishes that when you go to fire it up the first time that it runs and runs well.----Brian
ToniTD1490
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Nice work, "master". Could you put any pics how do you cut the gears?
ToniTD
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tel
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OK, Toni, and anyone else that might be interested - here's some shots.
There is not really a lot to see with gear cutting, the whole process is just repetition and relies on a good, solid set-up and some sort of procedure or order.
First, select a bit of stuff for the blank, turn the boss, face it, drill and ream for the bore.
Turn it end for end in the chuck and bring it down to the calculated outside diameter -i n this case 50t x 40 dp = 50 + 2 / 40 = 52/40 = 50 12/40 = 1 3/10" a handy 1.3"
If you need/want a shallow clearance boss on the face, now is the time to cut it.
Then set the blank on a mandrel and set it for centre height and depth of cut - I have omitted these steps as the mill was already set for this particular gear.
The dividing device uses is my handy, home made 'Harold Hall' simple dividing head.
The first gap is cut
and if all appears to be well, the indexing & cutting continues. Here we are cutting a 50t gear using a 50 master, so it's just every tooth. At a bit over a quarter of the way around the teeth heave into view.
Over half way now
not many to go!
All cut, when the last gap is cut, index back into what was the first space, if the tool cuts air you will know that nothing has moved and all should be well - if not, swear and scream for a while, toss the part in the bin and go back to square one.
And here it is (b/right) with the two I cut yesterday.
Talk about fate, or coincidence, or karma ..... while I was setting up for that last shot a bloke arrived that needs two little brass gears doing - you guessed it 40dp x 25t, how lucky can he be!
There is not really a lot to see with gear cutting, the whole process is just repetition and relies on a good, solid set-up and some sort of procedure or order.
First, select a bit of stuff for the blank, turn the boss, face it, drill and ream for the bore.
Turn it end for end in the chuck and bring it down to the calculated outside diameter -i n this case 50t x 40 dp = 50 + 2 / 40 = 52/40 = 50 12/40 = 1 3/10" a handy 1.3"
If you need/want a shallow clearance boss on the face, now is the time to cut it.
Then set the blank on a mandrel and set it for centre height and depth of cut - I have omitted these steps as the mill was already set for this particular gear.
The dividing device uses is my handy, home made 'Harold Hall' simple dividing head.
The first gap is cut
and if all appears to be well, the indexing & cutting continues. Here we are cutting a 50t gear using a 50 master, so it's just every tooth. At a bit over a quarter of the way around the teeth heave into view.
Over half way now
not many to go!
All cut, when the last gap is cut, index back into what was the first space, if the tool cuts air you will know that nothing has moved and all should be well - if not, swear and scream for a while, toss the part in the bin and go back to square one.
And here it is (b/right) with the two I cut yesterday.
Talk about fate, or coincidence, or karma ..... while I was setting up for that last shot a bloke arrived that needs two little brass gears doing - you guessed it 40dp x 25t, how lucky can he be!
tel
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Thanks blokes. Just a little postscript to the other set of gears I mentioned, then we can move on.
As I needed two identical gears this time, a dual 'time-saver' blank was prepared.
And cut as before
then parted off and cleaned up. Sorry about the quality of thes pic - the light was fast going when I took 'em.
As I needed two identical gears this time, a dual 'time-saver' blank was prepared.
And cut as before
then parted off and cleaned up. Sorry about the quality of thes pic - the light was fast going when I took 'em.
tel
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Not a lot of visual difference this update, but just to keep all y'awl in the loop.
The second set of timing gears has been installed.
Rocker arm (tappet) and bracket made and fitted - still needs some final shaping and finishing.
Two overall views as of today. Now to figure out what I'm doing about points.
The second set of timing gears has been installed.
Rocker arm (tappet) and bracket made and fitted - still needs some final shaping and finishing.
Two overall views as of today. Now to figure out what I'm doing about points.
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Hi tel
as usual you have inspired me.
I love the extra gear train, but I hope the extra drag of the twin gear train will not make it hard to get it missing ?
After being being flooded in the other day I started on a my own Kerzel using as much as possable bits of scrap.
I had promised myself not to start any new projects until I got a better vise for my mill,but i was isolated for a couple of days and the metal called.
as usual you have inspired me.
I love the extra gear train, but I hope the extra drag of the twin gear train will not make it hard to get it missing ?
After being being flooded in the other day I started on a my own Kerzel using as much as possable bits of scrap.
I had promised myself not to start any new projects until I got a better vise for my mill,but i was isolated for a couple of days and the metal called.
tel
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Thm: ONYA MM, nice to see another one underway. This one is almost entirely out of scrap material, so it can be done. There is almost no drag at all on either of the gear trains, I did spend a bit of time getting them pretty right and they run very freely with next to no backlash.
At the moment I am experimenting with a Honeywell microswitch in place of the points, although I will probably go back and make points at some stage. The microswitch, again, operates with virtually no friction, so I'm living in hope.
At the moment I am experimenting with a Honeywell microswitch in place of the points, although I will probably go back and make points at some stage. The microswitch, again, operates with virtually no friction, so I'm living in hope.
