AndyW

My Feedback: (1)

With the loss of Cox to offshore interests we may find getting glow plugs for our little jewels an issue. You can drill out and tap an old head for a standard plug but you'll lose considerable power and RPM. You can also drill out a head to accept Norvel plugs. But lately, Norvel plugs have been hard to get. If you have the tools here's a solution.

Full credit for this goes to Japanman. Last year he revealed that he found a way to install turbo plugs into a Cox head. Some horse trading later, I had a Cox turbo head but also a turbo button to use on Norvels.

I found little advantage to either so shelved the items until just a short while ago. My Brodak's ate my last good Norvel plugs, (not their fault) and I was stuck. The Brodak/CS .049 really improves when you replace the stock plug/head arrangement so I was kind of stuck till I stumbled on Japanman's turbobutton. As it turns out, it was a perfect fit for the Brodak and even gave me a small boost in RPM. Wonderful. The same button fits the Norvel .074 so I had to have more.

The tapered seat of the plug, according to Japanman is the same as the taper on a standard Phillips head screwdriver. You have to sharpen the flutes and I tried this but Jman is much more skilled than I. I just couldn't get a good result. Then I noticed that a pilot hole bit looked very close. I tried it and it's the exact angle required. The drill bit is 9/32" and the tap is an M8 X 0.75 bottoming tap.

Pictured are the tools needed. One button was made to match the head of a Norvel plug and the other is a hemi. Both work equally well. The smaller one is for 049/,06 and the others are for Norvel .074 and Brodak/CS engines.

The advantage here is that turbo plugs are made by OS, Rossi and others and are available in several heat ranges. For those running pipes, this could come in real handy.

Next up is to make a button for my VA.

SGC

Andy , I assume from your description the Turbo plugs are better than the Norvell buttons but not as good as Nelson plugs , is this correct? Looks like an easy DIY job , thanks for filling us in.
Stewart

SGC

Andy , What brand turbo plug are you useing and what heat range ??

AndyW

My Feedback: (1)

Actually, the turbos are pretty much equal to Cox or Norvel plugs. The extra few hundred RPM may have just been from running a slightly hotter plug. I've got a selection of Rossi's and OS's. Rossi offers some 8 plugs in four heat ranges and OS offers a hot, medium and cool. Soon enough I'll spend an afternoon comparing the effects of the entire range of Rossi's. When I was running a pipe on one of my Norvels it occurred to me that a cooler plug might be a good idea. Especially when I tried 60% nitro.

The gist of it is that we shouldn't be restricted to using one brand of plug with only one heat range for any particular engine. The turbos aren't cheaper but seem more durable and more importantly are available. The problem is that we need someone to mass produce the buttons.

I suspect that the turbos are equal to the Nelson's as the principle is the same. But I won't know for sure till I make a button for my VA. For some reason, when I ran my VA on a pipe, the Nelson's would cause flame out on acceleration. I had to modify a Norvel plug and use that to cure the problem.

GrahamC

hey Andy,

Cool! Another neat idea I will squirrel away for another day when I have more time to play.

I have a Nelson custom head for the Brodak 049. It doesn't fit the 061 and I don't have the 049 (yet). If you want to try it out and compare I can send it and a couple of Nelson plugs to Timmins and you can give it a try.

In fact, if you let me know sometime later today or this evening I can pack it up and have it on it's way tomorrow. My wife will be heading up tomorrow for a short visit.

cheers, Graham in Embrun near Ottawa Canada.

planophore @ aei.ca (home)
colling @ navcanada.ca (work)

AndyW

My Feedback: (1)

Graham,

I appreciate the offer but I'm puzzled by the Nelson head not fitting. The c/case for the .049 is supposed to be the same as the .06, the only difference being the cylinder and piston. In any event, my exprience has been that the Nelson plug didn't really add anything to the Norvels I've tried them on. Didn't hurt, but didn't help. Yes, I have tried the two heat ranges they offered and also the latest. What makes the button with turbo appealing to me is that it can be used on a CS/Brodak or a Norvel. But thanks anyway.

GrahamC

I compared what information I could find on dimensions etc. and a close comparison of pictures. Every little bit of evidence showed that they might very well be the same except in displace. They are very close, very close.

The Nelson head measures .636 inside diameter on the threads, the CS 061 about .639. I will start thread on about a turn but that is it. I can't see Henry making a mistake in machining the head. It would nice to compare physically side by each.

Oh well. You have peaked my interest on the 049 size that I will have to save my pennies and get one.

cheers, Graham in Embrun near Ottawa Canada

SGC

GrahamC,
I found the same with the Brodak/CS motors I have , the Brodak head will not screw on the CS but the CS will screw onto the Brodak , seems the Brodak maybe a close but different size thread. I also noticed the CS head hit the exhaust manifold befor fully seating on the cylinder of the Brodak,
Andy,
I noticed on both my CS motors (cant recall if the Brodak is the same)the piston does not come up to the top of the cylinder, makes we wonder if the engine may go better with a longer rod and more combustion area in the head to compensate, maybe require some port adjustments as well ?
Stewart

AndyW

My Feedback: (1)

Uh oh, don't tell me that they've made one metric and the other Imperial?? I suspect that Nelson got blindsided by the same thing.

Yes, my engine, stock, had the piston NOT run up flush with the top of the cylinder. BUT my best, modified Brodak used the stock Norvel rod and piston, the rod is longer and the piston runs up flush to the top of the cylinder. No doubt some radical timing differences. Maybe that's really where all the power is coming from. Havin' too much flying the thing but I guess I'd better get some timing figures down on paper before I have a flyaway, or something.

Stewart,

Might be an idea to use a Norvel rod and see how it goes with a Norvel plug without altering the head. If too much compression, just add some shims.

Japanman

Hi Andy!,
I have not done any turbo conversions since I got my lathe[8D] -I did yours on a drill press. But good to hear the centre drill works. Thats a lot easier than making your own cutter!
I have to go now, but I have something that I am sure you will be interested in I`ll let you stew on that untill next time

Stefan

AndyW

My Feedback: (1)

Hey Jman,

For a guy who does such innovative work on just a drill press, I fear that with a lathe, you're gonna be downright dangerous. [X(] But welcome to the club. Ya may regret it though, I seem to make more ally dust than balsa dust these days.

Can't wait to hear 'bout your project. [8D]

AndyW

My Feedback: (1)

I received a couple of PMs from folks who were not clear on this business of inserts and turbo retrofits so I took a couple of pictures of how these things go together. The first picture shows the stock Brodak head in blue. Note that a standard glow plug screws directly into the head. The drilled out head is at the top. The bore is large enough to accommodate a stock, Norvel .074 plug. This plug is the device in the middle of the picture. To the right of that is an insert containing a contra-piston for converting to diesel operation. The device on the left is the turbo insert.

The second picture is the top view for clarity.

The dimensions of all of these are designed to be used in a Norvel .074 and the CS/Brodak .049/06.

The third picture shows an insert for .049/.06 Norvel or Cox to the left, the .074/Brodak insert to the right. The only difference is the flange diameter.

bsindel

Andy,

Thanks for putting the whole thing together with pictures. It definitely
cleared things up for me.


Bill S. (the other Bill)

injunnut1

When you guys go to purchase your countersink cutting tool ( the tool that cuts the plug 'seat angle'), make sure you get the one with 60 degrees total angle cut. These tools can be had in different sorts of configurations and also different angle cuts, the most common being the 82 degree tool to match most common flat head screw angles, they also are available in a few other angles (90, 100, 120, etc.) ...... the tool you want is "SIXTY DEGREES". Right Andy?
BTW, the seat angle on the Nelson plug is 110 total degrees, as I recall?

AndyW

My Feedback: (1)

Hi Bill,,, and Jim,

You're welcome.

Injunnut1,

Geez, you're RIGHT !!! [X(] Thanks for pointing that out. I really didn't know what angle it was that we were dealing with. I just got lucky, I guess. I thought that the bit I had was just for locating center holes for boring on the lathe but it's clear that countersink holes is the deal here.

The set I got many years ago are simply numbered 2 to 5 with the correct bit to use being number 3 with a shank diameter of .25"

And here's where to get them. Proper name is centre drills.

http://busybeetools.ca/cgi-bin/produ...20705061107712

injunnut1

Andy,
According to one of my several hardware catalogs (McMaster-Carr), the tool that you are showing is called a 'Combined Drill and Countersink' ...... here are a couple other tool types that are used for countersinking, or beveling a hole's face:

AndyW

My Feedback: (1)

Hi Injunnut1,

Thanks for the info, especially the angle required to make turbo plug devices. My enthusiasm for making things out paces my knowledge or skill. I was relying on Busy Bee for the proper nomenclature. In any event, whatever it's called works real well as the tip drills precisely on center allowing the bevel to be cut very accurately and without chatter. Lots of cutting oil is recommended as there's no relief provided at the bevel cutting edge.

I'll have to get a McMaster Carr catalog, especially now that the Canadian dollar is catching up to the Greenback. At one time, it cost nearly 50% more in Canuck coin to buy something Stateside. Today it's only some 15%. What a relief.

Larry Driskill

Andy,

Here's your catalog:

http://www.mcmaster.com/

GrahamC

Hi Andy,

I have been finding it about the same price, sometimes cheaper, and often times as quick or quicker to buy stuff from the UK. They seem to have quite a selection of online suppliers tailored to the home machinist/model engineer enthusiast and have good selections. I just recently bought a small tool from one of these UK suppliers, I think I saved a couple of $$ over buying in the US and I received it in the mail in on Friday having orderd it on Monday. and Canada Post/Customs never gave it a a second look. Packages from the US almost always seem to getting the Customs/taxes added and are often taking 3 or 4 weeks.

I also buy from Aircraft-World in Japan (mostly electric stuf) and get the same kind of service, about $5 US for postage and usually have it within 7 calendar days.

cheers, Graham in Embrun near Ottawa Canada

Andrew

Getting a "paper catalog" from McMaster-Carr is tougher than finding hen's teeth. Even though I buy a lot of equipment for the University, I didn't qualify.

OTOH, Larry's link will get you what you want -- if McMaster doesn't have it, you probably don't need it. Countersinks are available in 60, 82, 90, 100, 110 and 120 degree bevels.

AndyW

My Feedback: (1)

Graham, Larry,

Thanks for the source tips. Can never have too many of those. When I decided to make my own turbo plug devices, I firstly shopped locally. This is a mining town, we have plenty of industrial suppliers but all were quoting 40 to 60 dollars for such a special tap. This held me back for a while but a quick poke at Google revealed many sources for the tap and one of them was in Cambridge Ontario at

http://www.newsontool.com/

Allen Newson is the owner and he answers the phone to take good care of you. He's a transplanted Brit, it's a family business and he's right friendly and takes an interest in your project. Toll free and his dime but he's still willing to chat, give good advice and take good care of your needs. Price for the tap? A big 15 dollars. Much of what he supplies is made in South Africa of all places. The story is that due to sanctions, the beleaguered country had to scramble to make their own stuff. Not third rate either, the tap I got is very well made with jewel like quality. PLUS he has drill bits in metric and imperial in incremental sizes, like 2.1mm. When making connecting rods, drilling with a 2mm bit usually means a tight fit for the pin. A final pass with a 2.1mm bit works perfectly. Cheaper than a reamer.

Another good source for the bits and pieces we need is Spaenaur located in Kitchener, Ontario. They have a thousand page catalogue with almost any kind of screw, nut, fastener and yes, special drill bits, taps etc. They do have a minimum billing though and sometimes minimum quantities but if you're ever stuck, they'll likely have it. See them at

http://www.spaenaur.com/

ptulmer

My Feedback: (5)

Here's another set of 60deg bits for those lucky enough to have a nearby Harbor Freight.

http://www.harborfreight.com/cpi/cta...emnumber=42280

GrahamC

Newson Tools, that's a good one. I will add it to my list of sources. I had a quick look through, even has such oddities (for this part of the world) as BA (for working on/restoring/reparing PAW's and other old English engines.) and other "standard" British threads. Cool! Now I can get them more locally which is always my first choice.


cheers, Graham in Embrun near Ottawa Canada

injunnut1

[Getting a "paper catalog" from McMaster-Carr is tougher than finding hen's teeth.]

'The Other Andrew" is totally correct about obtaining a hardcopy catalog from McMaster-Carr, it is nearly impossible! The only way I was able to obtain a McMaster-Carr hardcopy catalog was to fortunately know someone with a fantastic gift to Gab ..... this guy can talk the bark off a tree! Anyhow, this guy can somehow talk McMaster-Carr into not only one catalog, but EXTRA copies yet for his 'at large' Sub Station outlets <grin>. Fortunately I was able to talk this good friend of mine out of one of his extra copies (have done this twice now!).

That being said, actually 'MSC Industrial Supply Co.' is the best place to buy shop TOOLS (IMHO anyhow), better prices and bigger selection. McMaster-Carr excells in stocking the more unusual / harder to find general hardware items, while MSC excells more in offering very wide selection and cheaper foreign (as well as made in USA) brand name TOOLS. The reason I did not show MSC counter-sink tools last night was because the MSC site was temporarily down for servicing (about 3:00AM my time, EST). Plus the fact is is relatively EASY to get (just ask) their hard copy BIG BOOK Catalog with well over 4,000 (yes, that's FOUR THOUSAND) pages of merchandise ...... and their BIG BOOK Catalog actually does have HARD BACK Covers too! MSC offers a Compact Disk Catalog version also, plus of course their online catalog at www.mscdirect.com .............

AndyW

My Feedback: (1)

Burning the midnight oil, I got ambitious and made up a batch of turbo-plug inserts for the Norvel .061, 074 and CS/Brodak .049/.061

The top row shows buttons made for the .061. Various combustion chamber shapes were tried. Far right is a hemi, next is a trumpet, next is a shallow bowl shape, next is equivalent to Norvel and on the far left is a flat face. That last was to see what performance we'd get if you made the combustion chamber ALL squish band. Not yet tried.

The lower set is for the .074.

That was tried today. As related on another thread, the engine lit off when converted back to glow without having to touch any of the needles. As far as combustion chamber shape, The hemi ran well WOT but idle went rough. Never quit but became "noisy". The trumpet head sounded smoother with a smoother sounding idle. The shallow bowl was similar to the stock, Norvel shape.

A variety of plugs were tried, the black ones are from Rossi with a range from extremely cold to extremely hot. The silvery ones are by OS. The best plug of the lot is the OS P7 plug, I believe its a medium.