Member postings for Jeff Jorgensen

For the benefit of MikeT who seems to doubt the system ( pre PaulC mod) did actually work, see the video from over 2 years ago.

**LINK**

And how many times I have to acknowledge PaulC for making the improvment which arrived at todays design I will never know.

It might be noted that PaulC ran with my original idea and added and extra transistor stage and a reed coil but omitted to use a pulse capacitor as shown in my final circuit, but no mention of that anywhere.

Also, (for the Nth time for Mike T benefit)  the system DID work but PaulC addition/mod in the form of the coil certainly made an improvement.

No requirement for the extra transistor stage.

Use the circuit as you will but it was designed originally for those who build single cylinder engines and require spark ignition at both an affordable cost and with parts readily available off the shelf.

There is no requirement to use other than the parts I mentioned especially the coil type, no need for any "Arduino type relay". The HK19F-DC12v-SHG works fine, no changes needed OR if you REALLY want you can use a Jaycar 12v Reed coil (SY4038) @ around AUD $4.00 a piece if that floats your boat.

Made conversion on my Atkinson engine a couple of days back so tried and tested as they say.

With all that in mind 100% success.

Response from Mike T has ensured I will keep my ideas to myself in future. Seems to have a rock in his boot because the system for one reson or another ( only known to him ) would not work with some multicylinder engine. We never did receive any input from that to try to determine why , other than "it won't work" but there ya go.

Edited By Jeff Jorgensen on 13/08/2022 01:05:56

Edited By Jeff Jorgensen on 13/08/2022 01:08:10

Edited By Jeff Jorgensen on 13/08/2022 01:16:55

Edited By Jeff Jorgensen on 13/08/2022 01:20:29

As shown above, even a link supplied, one can get 50 for a few dollars on Ebay (3144)

Also as shown above, the original trigger sensor was a large coil so self explanatory really.

Edited By Jeff Jorgensen on 11/08/2022 23:42:40

Few dollars for 50 on Ebay...work just fine....

**LINK**

Mine did work, and I have the video evidence to prove it, however, I came to notice the spark was much less intense than when I did the mod.

In case you didn't notice, I have given PaulC full recognition for his modification in the drawings and elsewhere also.

No idea what you have there so can't comment really.

It was never initially meant for multi cylinder or multi ended spark coils however in the future I will try it on the V8 which will be via distributor, perhaps two and my standard design.

Don't know about the UK but here in Aus, the access to small ignition coils as were used in the old style motorcycles with kettering system, just don't exist and even if one could track one down, cost is expensive.

I have had success using a Ford BA Falcon on the plug coil stripped down as old Doc did in the states on one of his V-twin Harley engines but he used 6V and a large wattage resistor pack all driven by a 555 multispark unit. I used an off the shelf 18650 LiPo cell instead with basic points so perhaps that route might suit you better. I see one can buy a six pack of those coils online at Ebay for around AUD$40.00 so might be worth your trying and let us know how it goes.

Cheers Jorgo.

Edited By Jeff Jorgensen on 10/08/2022 23:46:57

Video here....... **LINK**

Been developing this for quite a while and have it pretty much as I originally imagined.

System uses largely off the shelf items and some modification/additions as required.

Basic parts are the 4 wire 12V DC "black box" CDI units, GY6 Ignition coil and the KY_003 hall effect module. For the HT coil wire, I cut the 1/4" thick HT lead close to the coil, strip back and add whatever length of Belden high voltage cable. This is around 4 mm thick and scale to some degree. In a couple of units for my mate George Punter whom some of you may know, I added a 1A diode in the power supply (Just in case......💥

Additional parts are a 2.5mm spacing 0.1uF capacitor, LED and 1k0 resistor, HK-19F DC12V SHG 8 pin relay (only uses the coil in the circuit) some small bridging cable, a miniature switch on off, and the add on board. Naturally as in the beginning, some veroboard could be used.

Seen all over in places like Ebay etc. and when I started out the above bits were around AUD$15 in total, now perhaps double that but still worthwhile.

The original CDI black box ran a pickup coil which was large and cumbersome for model work hence the need to convert to hall effect pick up. I have just completed a changeover on my Atkinson engine and it uses points. Although the unit is originally designed for 12v DC, this latter application works well on a 2s LiPo @7.4v DC.

To get the unit to function properly, it needed addition of some type of "coil kick" in the sensor. I played with this for a quite a while and during some discussion a fellow model maker, PaulC from homemodelenginemachinist literally fell on the idea of an inductive "reed coil" in the hall circuit and hence the CDI trigger which made all the difference. He added a transistor stage to the hall output to drive the reed coil but I have since found this unnecessary.

I simply added a miniature oftheshelf complete mini relay and use just the coil in circuit leaving the rest of the unit intact. The hall effect module has an onboard LED to use for timing settings.

The add-on board I designed, carries the above relay, connections for a power LED and resistor, connections for the hall effect module and connections to the CDI black box unit.

In the latter I now tend to keep power to the CDI black box and on off switch separate as those pcb traces seem mighty small when one gets to actually see it in real life, different to on the screen design. (EasyEDA)

If using in this manner then just battery power pos and neg to the add on board for the power LED, wiring to the KY-003 hall module and the trigger input wire from the add on pcb to terminal P1 on the CDI black box.

Important to emphasise the need to run a good earth from the battery negative to the engine frame for the spark return for obvious reasons.

Anyhow, I'll drop the files for the add on board and the circuit diagrams for both hall effetc and good old points in below. Points btw need just the hall effect signal wire and terminate the unused pos and neg.

Cheers Jorgo

Tried to upload jpg images of the schematics and a zip file with Gerber files for the add on board......no luck

ok then try this....go to this link..... go to post #184 

https://www.homemodelenginemachinist.com/threads/model-engine-cdi-easy-and-cheap.31128/page-10

Edited By Jeff Jorgensen on 10/08/2022 00:48:26

Usual arrangement these days is to go for a Lithium Ion pack (LiFePO4)as the nominal voltage is close to the original.

Pack is removed for charging on a dedicated charger however this only needs to be done at a much longer time scale than the original.

Packs normally are 1500mAh capacity @9.9V and cost around $10.00 from HobbyKing.

Of course there is additional delivery charge involved and chargers are available from them in a wide variety of models makes and cost.

Biggest benefit is the pack can be fitted to some of the newer 2.4g radios when/if you upgrade.

A little research will show which way to go, plenty of info on rc forums.

Hi Clive,

Being a 2 stroke, possibly the OS No. 8 would suffice.

When running four stroke on methanol it is necessary to run a four stroke plug.

They are much smaller internally to hold the heat during the exhaust stroke.

Another thing might be worth looking at are the new OS glow plugs developed to run petrol/oil engines.

It is labeled as an OS G5 glow plug and there are many discussions on the internet and video on use in different engines etc on youtube.

Cheers Jorgo

Using 4:1 methanol might be a bit difficult with a 1/4" spark plug as I think it would tend to foul up constantly, so I would stay with a glow plug.

If you modify the fuel mix of 4:1 (stay with the same oil content) and make you methanol content, 90% methanol and 10% nitromethane, it will assist in starting a lower compression engine.

It also has the effect of making the needle adjustment much less sensitive.

Cheers Jorgo

Methanol........................... 4 parts

Castor oil (castrol M)......... 1 part

Getting back a bit now and some of the gear is superseded but basics are all there to see.

https://www.youtube.com/watch?v=x02hMSPoDvo&ab_channel=iforce2d