|
Author |
Message |
WD Forte |
This post is not being displayed .
|
WD Forte World Chat Champion
Joined: 17 Jun 2010 Karma :
|
Posted: 00:54 - 05 Jan 2020 Post subject: this week I are bin pulling me wire again |
|
|
Picked an abandoned project off the shelf recently.
CX500 and 650 engines with Transistorised ignition use two pulsers mounted at the rear for timing signals
to trigger the spark units which in turn fire the coils.
All other ignition components are either still available or alternatives exist but the pulsers are NLA new.
This is a shame because the TI system is far better than the early CDI system and usually pretty damn reliable.
https://imgur.com/UemUaG2.jpg
The pulsers dont fail often, I've never had one fail in 10 years
When they do fail, one usually breaks down first and that's enough to stop play
and as their shape is unique to the L or R position, swapping from another set may only work if you find
a good SH one from the same side as your failed one and you're never sure how much life is left
in 30+year old one anyway.
I started taking a few failed ones apart a few years ago now, but as I have good spare units
and never had one fail on me, it was never a desperate issue to get done.
I knew I could wind a coil, I just wanted to see if I could
strip out, rewind and reassemble them in a timely and efficient way to produce a useful repair
On early efforts I removed so much of the body that I would have had to make shuttering or moulds to
fill with potting or epoxy to support and protect the new coil
it seemed to make the process too fiddly and time consuming IMO
I lost interest at that point
https://imgur.com/VWzXjRk.jpg
I later realised that cutting into just 2 faces would allow me to remove the old coils and fit new ones
with minimal potting and follow the original shape easier.
I made a jig to do this on my machine but later, found a Dremel with a 2.5 end mill is just as good if not better
quicker and less hassle too.
https://imgur.com/l8A5lis.jpg
Ok, so now I have a strip down process that doesn't take an age and works.
Testing:
Having to at least move the engine forward to fit another set of fully assembled pulsers
then refit the engine to test it without having a reasonable idea if they'd work or not
didnt seem like a good idea to me.
Some sort of test bed with rework options for any faulty ones did, so I built a rig to hold a spare ATU
I could spin to check the waveforms insulation etc were AOK before final potting up and assembly.
Then at least I'd a have some confidence it would work beforehand.
Here it is with known good pulsers ready to set up a bench mark for
my DIY ones
https://imgur.com/ZBSAdJH.jpg
Next, build the coils.
The wire I removed was 0.06xmm or 42awg as near as dammit and the manual states a nominal resistance of 530 0hms @ 20C
with an acceptable variation of 50 ohms either way, a bit of leeway there then.
I've had a reel of 42 gauge double insulated transformer wire for ages but reliable counting meant well.... counting, lotsa counting.
I considered building an Arduino type thing with motor, pulleys LCD display and all that shit
but K.I.S.S. right? so I bought a hand winder for £18.99.
The spindle was too long, too thick and useless for my purposes so I sawed it off short and used a 10mm collar
to hold a wooden 'tongue' thing to hold the bobbins I made from gasket paper and heat shrink.
An initial varnish keeps the end plates in place for winding
This is the rough initial setup but I'm making a proper/better reel holder before making any more coils.
https://imgur.com/CTFxdor.jpg
I dab the bobbin with transformer varnish before during and after winding so when it sets the coil is solid
and then give it a bit of glass tape to finish it off.
My second attempt after ballsing up the first one gave me 510 ohms at 4000 turns
Pretty damn close that, I'll do another at 4000 and test them on the rig before making any changes.
The handle drives the spindle at 8:1 so 500 turns gives 4000 winds and only takes 10-15 minutes or so
https://imgur.com/h0jkV7k.jpg
Thats all for now, shitty pics due to my being lazy and using the phone cam ____________________ bikers smell of wee |
|
Back to top |
|
You must be logged in to rate posts |
|
|
Sister Sledge |
This post is not being displayed .
|
Sister Sledge World Chat Champion
Joined: 17 Aug 2018 Karma :
|
|
Back to top |
|
You must be logged in to rate posts |
|
|
A100man |
This post is not being displayed .
|
A100man World Chat Champion
Joined: 19 Aug 2013 Karma :
|
|
Back to top |
|
You must be logged in to rate posts |
|
|
pepperami |
This post is not being displayed .
|
pepperami Super Spammer
Joined: 17 Jan 2010 Karma :
|
Posted: 15:23 - 05 Jan 2020 Post subject: |
|
|
Top Sausage Sir
More of the same please so that we all may learn and not be so reliant on the corporations/manufacturers.
Who wants to buy a new one when you can mend the old one ____________________ I am the sum total of my own existence, what went before makes me who I am now! |
|
Back to top |
|
You must be logged in to rate posts |
|
|
Pete. |
This post is not being displayed .
|
Pete. Super Spammer
Joined: 22 Aug 2006 Karma :
|
Posted: 19:28 - 05 Jan 2020 Post subject: |
|
|
Nice work. People think that those little black blocks contain magic but they are nothing more than a coil of wire.
Last coil I had to wind needed 14,000 turns. I set my lathe to 700rpm and used a stopwatch. ____________________ a.k.a 'Geri'
132.9mph off and walked away. Gear is good, gear is good, gear is very very good |
|
Back to top |
|
You must be logged in to rate posts |
|
|
WD Forte |
This post is not being displayed .
|
WD Forte World Chat Champion
Joined: 17 Jun 2010 Karma :
|
|
Back to top |
|
You must be logged in to rate posts |
|
|
pepperami |
This post is not being displayed .
|
pepperami Super Spammer
Joined: 17 Jan 2010 Karma :
|
|
Back to top |
|
You must be logged in to rate posts |
|
|
Pete. |
This post is not being displayed .
|
Pete. Super Spammer
Joined: 22 Aug 2006 Karma :
|
Posted: 21:35 - 05 Jan 2020 Post subject: |
|
|
TBH there is a good argument for fully encapsulating the pickup coils. Is the plastic housing actually hollow inside? Looks like you had to chew the whole space out with the dremel.
BTW if it ever helps there's a handy page for figuring coil parameters:
https://www.circuits.dk/calculator_multi_layer_aircore.htm ____________________ a.k.a 'Geri'
132.9mph off and walked away. Gear is good, gear is good, gear is very very good |
|
Back to top |
|
You must be logged in to rate posts |
|
|
WD Forte |
This post is not being displayed .
|
WD Forte World Chat Champion
Joined: 17 Jun 2010 Karma :
|
Posted: 19:19 - 21 Jan 2020 Post subject: |
|
|
Right, after a few balls ups some progress
First to answer Petes question
As far as I can see, the original bobbins are wound, taped, dropped in then sealed
probably thermally, in the assembly.
Here's a pic of one I cut out without completely destroying it
https://imgur.com/ytljfl9.jpg
The windings came out loosely so they were not potted, just taped.
I think its feasible someone with enough practise, patience and dexterity could probably disassemble one
and re use the bobbin.
Pete very kindly sent me some 3D printed Bobbins based on my ill thought out, vague dimensions and I wound a few sets before realising my error.
The winding process even with such fine wire, exerts enough pressure to push out the end plates
so the overall thickness too damn close to the magnetic tip the rotor sweeps past and doesn't give much room for potting them
Bollox!
https://imgur.com/B819noH.jpg
more clearance
https://imgur.com/yrkmuWW.jpg
Trial and error and all that eh?
I put the project aside for a day or two as I sulked then had another go.
I made two bobbins the hard way and stiffened them with epoxy then wound 4100 turns on them
and got about 540/550 ohms on them which was promising.
These at least sat down without fouling the magnet/rotor area so testing for balls ups
as I went, I soldered on heat resistant wire and potted them in JB weld.
https://imgur.com/0NasygU.jpg
Testing:
My home made test rig isn't tool room quality, it's knocked up from pieces of MDF flooring
and Perspex bolted together
In use, the rotor is expected to spin past the pulser tip at a distance close to 0.5mm
Distances even just slightly closer or further away will affect the induced voltage so a gap of say 3mm
probably wont give much of signal.
Speed also has an effect, the higher the speed, the higher the voltage.
Flux density/strength of magnet field plus number and thickness of windings are also factors.
All I could reasonably expect is to get a fair/ballpark idea of a pulsers effectiveness
and my DIY ones gave as a good waveform as the stock ones.
I ran the rotor with a battery drill with a hex key in the chuck
10 hz Frequency equates to 600 rpm
Voltage variations from old to new pulsers are probably due to air gap variations
which were just eyed up as I fitted them.
Old
https://imgur.com/iReeTyM.jpg
New
https://imgur.com/HLeq0iv.jpg
I'm satisfied that electrically they'll behave very closely to the stock pulsers
Thassit I'm done with this project.
Thanks to Pete for the generous donation of bobbins.
I don't need a pulser so its not high priority, I just wanted to know that if I had to,
I could build a set of working pulsers and complete a project I'd left half done for years.
I could do it again and probably better due to the lessons learnt but it was always
in the back of my mind that a gear tooth sensor could probably do a better job.
All the off the shelf sensors I found were too big physically for the limited space
but I found gear tooth sensing ICs from Allegro that will run up to 24V and cope with temps up to 150C
and those would be my choice.
They give a good clean output at any speed and are a lot more forgiving on air gap variations.
A bit of base plate modding and one of these things would be my choice.
https://i.ebayimg.com/images/g/GIIAAOSwEetV~71z/s-l500.jpg ____________________ bikers smell of wee |
|
Back to top |
|
You must be logged in to rate posts |
|
|
WD Forte |
This post is not being displayed .
|
WD Forte World Chat Champion
Joined: 17 Jun 2010 Karma :
|
Posted: 16:40 - 22 Mar 2020 Post subject: |
|
|
My spare engine is now assembled
https://imgur.com/YlKBcnR.jpg
https://imgur.com/yq3Tks1.jpg
I've since sprayed the rocker covers silver
I used a spare car battery to spin it up sans plugs to check oil pressure and
that oil is getting up to the rockers
All looks good so will stash it away for a while
It has the rebuilt ignition pulsers fitted and I'll fire it up in anger in the summer ____________________ bikers smell of wee |
|
Back to top |
|
You must be logged in to rate posts |
|
|
Old Thread Alert!
There is a gap of 1 year, 87 days between these two posts... |
|
|
Brava210 |
This post is not being displayed .
|
Brava210 Crazy Courier
Joined: 04 Dec 2005 Karma :
|
Posted: 20:05 - 17 Jun 2021 Post subject: |
|
|
Nice Curtains ____________________ Honda Novio, Puch Grand Prix, Suzuki AP50, CZ 125, Wassell 125, Montesa 348,Honda 125TDC, Suzuki 100ER, Suzuki GSF650 Bandit, Aprillia Pegaso, Honda PCX125, Honda Forza300, BMW G310 GS, Suzuki SFV650, Honda CB500X
CHARLEY SAYS " ALWAYS TELL YOUR MUMMY BEFORE YOU GO OFF SOMEWHERE" |
|
Back to top |
|
You must be logged in to rate posts |
|
|
bugzsprinter |
This post is not being displayed .
|
bugzsprinter L Plate Warrior
Joined: 11 Dec 2021 Karma :
|
|
Back to top |
|
You must be logged in to rate posts |
|
|
struan80 |
This post is not being displayed .
|
struan80 World Chat Champion
Joined: 04 Nov 2014 Karma :
|
|
Back to top |
|
You must be logged in to rate posts |
|
|
Bhud |
This post is not being displayed .
|
Bhud World Chat Champion
Joined: 11 Oct 2018 Karma :
|
|
Back to top |
|
You must be logged in to rate posts |
|
|
trevor saxe-coburg-gotha |
This post is not being displayed .
|
trevor saxe-coburg-gotha World Chat Champion
Joined: 22 Nov 2012 Karma :
|
|
Back to top |
|
You must be logged in to rate posts |
|
|
WD Forte |
This post is not being displayed .
|
WD Forte World Chat Champion
Joined: 17 Jun 2010 Karma :
|
|
Back to top |
|
You must be logged in to rate posts |
|
|
stinkwheel |
This post is not being displayed .
|
stinkwheel Bovine Proctologist
Joined: 12 Jul 2004 Karma :
|
|
Back to top |
|
You must be logged in to rate posts |
|
|
Old Thread Alert!
The last post was made 2 years, 101 days ago. Instead of replying here, would creating a new thread be more useful? |
|
|
|