Yet Another Webster Begins

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I used a set of Lucas points and condenser £2.95 on eBay and the coil from a scrap yard as you can see in the pics the coil and condenser are mounted underneath inside the box.

I like it!

One of the things I picked up by looking around is that if you build a lot of engines, you either duplicate the ignition system a lot of times or you build one into a box and make it as portable as possible. It seems a lot of guys use one box between various models. One of my thoughts behind the electronic ignition was to do that, using the CDI module (a black plastic box) instead of the coil and cap. I need to flesh out those plans and design a little box.
 
I have just made an ignition box on the 3d printer, it has the batteries in the bottom section then the rcexl ignition and switch in the top and a tacho in the lid. each engine has a hall sensor so you just have to plug in the sensor and put the plug cap on and it is ready to run. some of my better engines have the ignition built in but the others just use the common one. this one is for my son so I don't have to buy a new ignition for every engine.
The hall sensors are good because they are so small and you can be creative in the way that they are mounted.
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it was posted about using points with a cdi or electronic ignition, the answer is yes. in this config it is nothing more than a switch or trigger just as the magnetic hall effect switch is. cdi or electronic needs some sort of a "switch" thing is that since you aren't flowing the high energy through the point then they don't break down nearly as bad as non cdi. your points just become a low voltage on and off switch at this point. which helps with the break down of points systems such as pitting due to arking and such. long story short with most cdi all you need is a simple on / off switch happening at the right time. just like points do. except with cdi points usually don't arc and such coming from the condenser which isn't needed any more either. hall effect is a wonderfull thing on my old farmall. everytime I would leave that tractor out and it got wet I had to replace the points. havnt had to do anything in over 10 years since replacing with a pertronix hall effect ignition.


all that said the points work just fine for the Webster and are very simple. no adaptation needed to modify the plans for hall effect magnet switching.
 
Hi all. Just what is probably a basic question for you Webster builders. I am considering using the Minimag system same as I used on my Wyvern engine. Question is, would the Hall pick up magnet need to be fitted to the larger cam spur gear in order to pick up half engine speed? Thanks.
 
Hi all. Just what is probably a basic question for you Webster builders. I am considering using the Minimag system same as I used on my Wyvern engine. Question is, would the Hall pick up magnet need to be fitted to the larger cam spur gear in order to pick up half engine speed? Thanks.

I think that's right. It would go near the exhaust cam on the bigger gear. Attached somewhere, somehow. The exhaust cam pushes the lever that opens the exhaust valve, so that's almost a full cycle of the piston past where the spark plug needs to fire. Maybe that means it would be opposite the top lobe of the exhaust cam.
 
I have just made an ignition box on the 3d printer, it has the batteries in the bottom section then the rcexl ignition and switch in the top and a tacho in the lid. each engine has a hall sensor so you just have to plug in the sensor and put the plug cap on and it is ready to run. some of my better engines have the ignition built in but the others just use the common one. this one is for my son so I don't have to buy a new ignition for every engine.
The hall sensors are good because they are so small and you can be creative in the way that they are mounted.

That's a very nice implementation. I've been thinking of doing something like that, but haven't thought it through well enough.

Do you have a small 6V Gel Cell in there, or a pack for four alkaline batteries? Here I go assuming yours runs on 5 to 6V like the one I have.

I'm getting ready to go out of town for Thanksgiving. I'll see things tomorrow.
 
Hi all. Just what is probably a basic question for you Webster builders. I am considering using the Minimag system same as I used on my Wyvern engine. Question is, would the Hall pick up magnet need to be fitted to the larger cam spur gear in order to pick up half engine speed? Thanks.
you can have the hall sensor on the crank, you will have a wasted spark at the top of the exhaust stroke. makes mounting a lot easier.
 
Do you have a small 6V Gel Cell in there, or a pack for four alkaline batteries? Here I go assuming yours runs on 5 to 6V like the one I have.

I'm getting ready to go out of town for Thanksgiving. I'll see things tomorrow.
this unit runs off 6 -12v so i am using 4 AA batteries, some of the earlier rcexl units were 4.5 - 6v and use 3 AA batteries.
I have tried some cheap Chinese CDI that say they are 6v but are more reliable on 4.5v
 
I'm expecting to try to get it to run today. The holidays and working on my bike intervened. My version of your "old man's walk" is I ride a road bike for an hour a few times a week.

I was going to try to test the electronic ignition a couple of days ago and I ran into something I'd never seen before. The cam would push the points open but they wouldn't close on their own. I took them off the support and they hardly moved in my hand. After an hour of poking and prodding, and everything I could think of, I put drop of oil in the right side and they started to work better. They seem to work now.

It has been nearly 40 years since I worked on a car engine with points but I swear I don't remember EVER oiling points. Or even hearing about oiling points.

My plan was to sit down with the forums and try to see what other people went through getting their Webster to start for the first time.
 
Put a dab of grease on the white nylon rubbing block where it rubs on the points. If you don't, it will wear away in a very short time.
 
Are you by any chance nipping the points spring with your cap head screw?

I thought that might be the case and backed the screw out. It didn't make a difference.

Put a dab of grease on the white nylon rubbing block where it rubs on the points. If you don't, it will wear away in a very short time.

That part I got. The points from NAPA came with a little capsule (I mean it looks like a drug capsule) with some black grease in it. I've applied that.

Since I've never seen one of these Traxxas carbs, what settings do you recommend? I backed the needle valve out (I think) by about a quarter turn. Does the air intake go to minimum to emulate a choke? Richer fuel, lower air?

I verified my spark plug sparks, so I'm just going through the final steps before first attempt to fire it up.
 
It doesn't run. I suppose I would have passed out from shock if it had started up, so maybe it's good to not get a concussion on my concrete floor.

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I'm using Coleman fuel with a shot of WD40 in the bottle before I added the fuel.

I'm using a battery powered drill/screwdriver. It sounds better on it's faster speed, low torque setting but doesn't try to keep running. The intake valve only makes tiny movements, it doesn't get pulled down strongly.

There are three adjustments on the carburetor. The big one on the "arm" with the fuel inlet, the thing I'm used to calling a throttle plate on the top, and another small screw with a spring on it, just hidden by that lever on the throttle plate. I could use hints on how to set those. I've backed the big one on the inlet arm out a full turn, but not more, moved the throttle plate a few times and adjusted the small screw out by quarters to a full turn out. I have no idea if fuel/air mix is getting to the cylinder.
 
You can google for Traxxas carb settings. They should run without any adjustment, just as you buy them. If you have been twisting screws you have probably buggered something up. Traxxas maintains a web page about their carburetors. I have had to refer to it in the past. It is doubtful that you will see the intake valve move very much. If you have a transparent fuel line you should see the carb lifting fuel up from the tank as you crank it over.
 

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