Plastic stunt tank on a Black Widow?

Although I have seen black plastic 8cc tanks, I have never seen one with the over/under stunt vents. The plastic backplates are something we just learn to live with, even on some pre-'96 real BWs. If you buy it and it doesn't have stunt plumbing, you can plug one of the backplate vents and use a syringe with a needle to fuel it and it won't leak while inverted.

The main question is whether it has SPI and which kind. A good old real pre-'96 BW will have a full length piston skirt and the exhaust port will be open(no slit) and cut low enough so the bottom of the skirt opens a small SPI gap at TDC.

I'm not sure the '96 and later BW engines with the slit exhaust even had SPI. The extra bypass boost flutes were supposed to enhance performance even without it. That's debatable. If it has a slit exhaust and SPI, then SPI is achieved by using a short skirted piston rather than a low exhaust opening. This is because all slit (Surestart type) cylinders had identical architecture. Contrary to popular opinion, many people believe the slit cylinders are as good as the old open port jugs. It's been said that the open ports were way overkill for the volume of exhaust that passes through. However a little known fact is the old #1 BW cylinder also had deeper bypasses than other dual bypass Bees. So as with many Cox engines, who the hell really knows. For 25 euros, I'd buy it. Run it. Have fun. Some go fast and some don't, and we don't always know why.

Or, if you want a real pre-96 BW with a #1 cylinder and metal stunt tank, hold off until you find it, but expect to pay a lot more money. You can also order new versions of the old BW and Tee Dee cylinders form Coxinternational.ca under the performance tab. They take surestart cylinders and lower the ports and install full skirted pistons. They also hand fit the pistons. You may have to buff out some swarf from the machining work, but they will run like the good old Cox stuff.
Sorry for that useless essay.
Rusty

Rusty, your "essay" is far from useless. Keep'em coming, all of you, this is my favourite stuff to read Good point with "having fun", that's what this is supposed to be all about. I get too serious with my collector habits sometimes.

The world of these little engines amazes me. Just a few months ago I thought that all of them were the same, maybe some of them anodized differently and I also (casually) noticed some of the "Cost Improvement" changes like plastic backplates etc. Also paid attention to "the ones with the carb on the front" but never really gave them much thought. Then I just stumble on a box of old engines, buy it on an impulse, start looking at that strange-looking blue-and-yellow engine, google a bit and boom! A new world. The engine in question turned out to be an RR1 in very good condition. It's pictured in my avatar. So I started a collection. The beginner's luck with the RR1 was either a blessing or a curse, I haven't yet decided

Back to the topic, It could be that the seller is mistaken on the tank material. Maybe he's seen some black plastic tanks and sort of associates in his mind. We agreed that he'll ship the engine (and the plane attached) after Christmas, so I just need to be patient

Looks like I can't go terribly wrong with this one either. If the engine is a pre-96, great, if it's not 100% what I am looking for, it is anyway a good starting point or a display piece. I'll keep looking for the perfect one then, with the #1 cylinder and the metal backplate. This deal is like a gamble, where I'll either win big or small. Can't really lose. Do I already sound like an addict with all this "rationalizing"? Just feels so good to be excited about something, it's been a while since the last time.

Glad I could help. That RR1 is a great engine. Here are a couple of videos of mine. It's great that you've gotten back into it.

https://youtu.be/wXL2t4eKn-I




https://youtu.be/PUZz-uQNZN4

Good Save Twice on that second vid. man that RR1 is loud even with a muffler Eric

If the tank on the BW engine is indeed plastic, it is almost certainly the Estes version of the engine. Basically, cylinder and spinner aside, nothing else but a Babe Bee with 8cc tank; whereas the filler vent is located on the backplate and not on the tank itself. We have one like that in our collection and no idea why Estes would have dared to label it as a "Black Widow" engine lol.

KariFS wrote:

Back to the topic, It could be that the seller is mistaken on the tank material. Maybe he's seen some black plastic tanks and sort of associates in his mind. We agreed that he'll ship the engine (and the plane attached) after Christmas, so I just need to be patient

Looks like I can't go terribly wrong with this one either. If the engine is a pre-96, great, if it's not 100% what I am looking for, it is anyway a good starting point or a display piece. I'll keep looking for the perfect one then, with the #1 cylinder and the metal backplate. This deal is like a gamble, where I'll either win big or small. Can't really lose. Do I already sound like an addict with all this "rationalizing"? Just feels so good to be excited about something, it's been a while since the last time.

Thanks guys for all the help and information. Rusty, that RR1 is one angry-sounding engine I don't think I'll dare to fly mine though, but definitely will run it on a test setup.

Anyway, I finally got my Black Widow in the mail yesterday (well, I did tell the guy "no hurry"). The tank is aluminum, looks painted but I suppose it is anodized. It has stunt ventilation and plastic non-vented back plate. Now the good part: It has the open port exhaust, SPI cylinder with a faint #1 below one of the exhaust ports. So it's the real deal, I'm happy

Nice Looking engine KariFS , good price too that should make you a strong runner . You have plans for a plane to mount it on ?

getback wrote:Nice Looking engine KariFS , good price too that should make you a strong runner . You have plans for a plane to mount it on ?

Thanks. Plans are all I have right now as far as planes go When it comes to control line flying, I am not even a beginner yet as I have yet to build my first plane. I have the balsa sheets already, and a design for an all-sheet trainer plane. I have built balsa planes before, but never actually even seen a C/L fly "in person".

I have been surfing Outerzone.com, looking for plans for box-fuselage, built-wing planes, something that I could first fly with an extended-tank Babe Bee, then give it some more power with the Black Widow. But it will be a while before this one gets to fly.

Is that the 25 Euro engine? That was quite a nice find. Maybe you can get us a video of a break-in run on the workbench. Looking forward to you getting a model built. Make sure it's a tough one.
Rusty

Yes, that's the same one. I must say I was thrilled to see it had that cylinder.

The model I have in mind is "Scorpion", I modified the plan a little, added the engine mount etc. I think I'll extend the tail a little for stability, and the nose to get the CG to where it needs to be without extra weight. It's all sheet balsa, and for obvious reasons I'm aiming at "an easy to build, hard to break" design The engine will probably be a late-model Babe Bee with a muffler and a left-hand 6x2 prop.

Here's a link to the plan and instructions:

http://www.outerzone.co.uk/plan_details.asp?ID=5973

Right now my garage/shop is a mess and there is no heat either so all the gluing will need to happen inside the house. Sanding a wing profile from solid 1/4" sheet needs to happen outside, no problem, it's not TOO cold to do that, but fuelproofing and painting will be a challenge. We'll see. But there will be a thread once the build begins

When the weather permits, I'll try to get a couple of engines running on a test bench. I have pretty much all the equipment already, just need to build a battery pack from 2 or 3 DD cells and mix the fuel.

For the sake of the plastic mounting lugs, I suggest you get some 2-56 socket head hardware with flat washers and blind nuts for the model. And depending on your test stand, maybe some nuts and lock washers or nylock nuts.
Rusty

http://www.outerzone.co.uk/plan_details.asp?ID=5973 neat looking plane after some flying put a TD on that for some excitement !! Eric