What Glow plug do you use?

The local hobby shop caters to the RC car and RC airplane people. 80% of what they sell is RC cars. There is not a good selection of airplane stuff and nothing for CL. I have been buying OS A3 plugs they seem to work for a while then give out.

Marshal gave me a THUNDERBOLT Idle bar R/C Long Glow Plug Item # 115493. Its the best glow plug I have but I can not find anyone that sell them. None on ebay either.

I see a lot of 10 pak McCoy MC-59 and 10 pak McCoy MC-9 Glow plugs on ebay not sure if they are good or not.

Gary,I use OS #8 or A3. I have only burned one out all season.

Try Randy Smith,

Aero Products: His is listed here on (SSW) site as a Supplier.
He has the Thunderbolt R/C Long Glo Plugs. I have had one in my
PA .51 for three years and it's as good as a new one!

Try "Hobby People" for Thunderbolt glowplugs!!
Sometimes they run a special on them!
Like the one that JUST ENDED!!! $2.99 each!

Call them at: 1-800-854-8471

or order on-line at:

www.hobbypeople.net

YES! They're great plugs that LAST & LAST & LAST!

I use Merlin standard 'hot' glow plugs (non-idle bar) in my stunt engines. I'm very happy with the performance.

For contact information go to:

http://www.merlinglowplugs.biz

Prior to these, Sig R/C longs were my favorite, followed by the Thunderbolt R/C longs.

Fred

I like & use Thunderbolts...idlebar R/C Long in some engines, Four Stroke plug in others, and I order them from Hobby People, online. They are made by Ohlsson, as are K&B and the new Zinger glowplugs. The Zingers appear to be identical, and may be easier to get at your LHS. Frequently, a Thunderbolt R/C Long glowplug has corrected the occasional foul running engines that show up at the field, and I found that I was down to 3, from 12, yet have never burned one out, near as I can recall. Did use them in K&B .40S, OS .46LA, Magnum XL .25 and ST G.51, so that's 4 I used, and 5 that improved somebody else's day. Steve

LAST EDITED ON Dec-04-03 AT 02:40 AM (CST)
 
The McCoy plugs are very good, only I don't know if they're very good for Stunt. They're probably OEM'ed by Ohlsson, like almost every other US made plug out there other than Fox and Fireball. The nitro boat and ducted fan people use them by the handfuls, and they're great Combat plugs (well, at least until the Nelson .36 came along..).

Oh wow...

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3161648387&category=34056

> they're great Combat plugs (well,
>at least until the Nelson .36 came along..).

To be more explicit, combat people use Nelson plugs.
For Nelson engines, of course, but also for 15s and 1/2A's
(you can buy special heads for many common engines
and Henry will convert other engines). They're cheap,
they're reliable, there's no washer to lose, and they
offer more power.

How more power? Normal plugs seal at the washer, so the
(tiny) space around the threads is effectively part of
the combustion chamber. Nelson plugs seal in a taper
at the hot end of the plug, keeping compression where it belongs.

Incidentally, Rossi caught on, and now sell "turbo" plugs based on the same idea (but with the common 1/4x32 thread, and are thus smaller than the Nelson plug). The only problem is that the Rossi turbo plugs are a heckuva lot more expensive.

All Ohlsson plugs are not the same. Most brands went from .008" wire to .005" wire 30 years or so ago. McCoy was selling .008"-wire plugs recently.

I use an(Ohlsson)Thunderbolt R/C long plug in my OS .40VF. Some years I change it, and some years I don't.

LAST EDITED ON Dec-05-03 AT 04:00 AM (CST)
 
No, I imagine they're not (and didn't mean to imply that they were), since Ohlsson just makes them to whatever specs are wanted by the seller.

There's more than one kind of McCoy, too. They had, last time I contacted them, maybe 5 kinds. The MC-109s (I think they're called MC-9s now) were, if I recall correctly, the high nitro plugs that the boat and ducted fan people liked. The 58s and 59s were the "sport" plugs. They also had a "4 stroke" plug (what exactly IS a 4 stroke plug, anyhow..?).

I had a look on ebay yesterday.. someone's selling OS #8s for $45 a dozen.

Steve, you sound like me. I also use the Thunderbolt and give more away than I use.

My favorite plugs are the Thunderbolt premiums and RC longs. They just run better than others and last a long time.

Second is the Fox RC long with the idle bar cut off...I experimented with the bar cut off and found runs better than the Fox standard plug. Cutting the bar off was originally just an experiment and I had no other reason for doing it but it worked. Looking under a scope showed the wire is a different size between their rc and standard plugs. I tried the Fox Miracle plug several times but never had good performance with it.

Third favorite and still experimenting with are the Fireball hots...I burn them out faster than others and notice a tad richer burns on some engines. These were cheap and easy to buy...$20 per card from a guy on ebay. I wish the Thunderbolts were like this.

All my runs are done on 5-10% nitro, Fox and McCoy engines with 25%-29% castor at sea level.

In the NW and while at a contest one can go to very nearly every competitor, ask to borrow a glow plug and be handed a Thunderbolt long.

It might have an idle bar, if it comes from my stash it will not, but these are very nearly the universal plug-'n-play glow plug up here.

(I see no difference in the the performance of idle bar and standard Thunderbolt plugs. It's just that I had a spot-welded bar come off a plug years ago, thoroughly trashing a favorite RC motor. Have only very rarely used them since, even with one-piece plug bodies available, no spot-weld lashups.)

The O.S. #8 glow plug is excellent in all ways. Well, except for price. I once had an engine down at GMA's place, he was throughly impressed with very steady runs on his test stand, to the point where he called just to find out what plug was in the motor. I guess he couldn't see the "8" stamped on plug body. Or just wanted to talk.

For the four-strokes I am using supplied plugs for run-in, toss 'em as soon as motor is installed in a model. I then switch to the YS plugs; a lot cheaper, especially if buying them from Central Hobbies. Note: YS plugs are made by O.S. and to the same specs as their "F" four-stroke plug. The only difference is the marking on the body.

I believe PW is using the YS plug as well. There seems to be little reason to having a lot of spares; excellent, long-lived plugs.

While I may be the only person doing so, I have had real good success in using the Tettra fitting kit for remote activation of plug. The connector for plug is quite light and reliable, although it fits much better on four-stroke plugs than it does other body shapes. With the rear-intake four-strokes I now have one less reason to place delicate fingers in vicinity of the prop.

I agree with Dan. I use the YS plugs in my 4-Strokes, too.

>In the NW and while at a contest one can go to very nearly
>every competitor, ask to borrow a glow plug and be handed a
>Thunderbolt long.
>
>It might have an idle bar, if it comes from my stash it will
>not, but these are very nearly the universal plug-'n-play
>glow plug up here.
>
>(I see no difference in the the performance of idle bar and
>standard Thunderbolt plugs. It's just that I had a
>spot-welded bar come off a plug years ago, thoroughly
>trashing a favorite RC motor. Have only very rarely used
>them since, even with one-piece plug bodies available, no
>spot-weld lashups.)
>
>

>Dan

Dan, first time I took the Mutant Magnum out, I fired it off, it ran ok for about 30 seconds and quit. Restarted, it ran another 30 seconds and quit. Hmmmmm. I put in a new Thunderbolt with idle bar, noted that the original was a T-bolt without idle bar, it then ran fine, and it's still running on the same glowplug. You might want to try the T-Bolt 4 stroke plug, as it doesn't have an idle bar. I've only run them in the 2Star .60bb, and it's been sweet. Steve

Steve http://www.nwskyraiders.com/index.html

Al will also re-element a plug if you have a special plug. He provides this service to the speed guys. And at a fair price too.

Does he do Cox 1702s? I imagine there'd be a LOT of demand for those...

(He ought to do it for the RC car people - have you seen what RC car plugs cost? Ridiculous!)

Incidentally, the Russians also re-element Nelson plugs. You have to trade in burnt out ones. The nice thing is Nelson plugs seem to last and last.. especially in 1/2-As. I haven't blown one yet.

" The nice thing is Nelson plugs seem to last and last.. especially in 1/2-As. I haven't blown one yet. "

From a speed fliers stand point, that means you have not pushed the engine to its limit. Don't know about cox style plugs. I have a bag of cox heads i want him to do but have not got to it. There's also a guy in finland? or sweden? that does plugs.

LAST EDITED ON Dec-12-03 AT 01:45 AM (CST)
 
>From a speed fliers stand point, that means you have not
>pushed the engine to its limit. Don't know about cox style
>plugs.

Yeah, but then again, the Nelson plugs last a lot longer doing the same exact kinds of runs than lesser plugs. For comparison in 1/2-As, I've used two different types of Norvel plug and Cox 1702s. Nothing to complain about, in any case..

>I have a bag of cox heads i want him to do but have
>not got to it. There's also a guy in finland? or sweden?
>that does plugs.

Possible - if it's Jari Valo, he might actually be sending them off to get re-elemented in Russia/Ukraine/wherever (since he sells Russian equipment).

Pat Willcox had some Nelson-compatible plugs that were made in Taiwan, once.. he said the threads weren't quite just right, though.

LAST EDITED ON Dec-05-03 AT 07:22 AM (CST)
 
2 stroke...OS #8; 4 stroke...OS F.

You can get Thunderbolts from Leonard, the host of this forum. With all Len does for us by maintaining this site I would hope we all would try to patronize him with our business where possible. See the SSW web site.
Thanks,
Brian

>Marshal gave me a THUNDERBOLT Idle bar R/C Long Glow Plug
>Item # 115493. Its the best glow plug I have but I can not
>find anyone that sell them. None on ebay either.

Get all you want, from the source:

http://www.hobbypeople.net/mfr/T-BOLT01.asp

I use the 4-stroke plug exclusively. It's probably as hot as it gets. BTW, there's no particular rule about how much nitro you can use with a given heat range plug - it depends on a lot more than just the nitro.

>I see a lot of 10 pak McCoy MC-59 and 10 pak McCoy MC-9 Glow
>plugs on ebay not sure if they are good or not.

I had reasonably good results with the MC59 and MC55, but the Thunderbolt is better and a lot easier to get.

BTW, there's no particular rule about how much nitro you can use with a given heat range plug - it depends on a lot more than just the nitro.
> Brett

...and those other variables are?

I remember Mr. Aldrich specifying that the TB 4S plug was not a good choice, IHO, for fuels over 15% nitro. Since he forgot more than I'll ever know about model engines I think I'll trust what he had to say.

I'm still eager to see your opinion though...I don't consider you to be dumb as a post by any means either.

Fireball Hots and Fox. When the weather gets chilly, the Fireballs don't work as well, start wise. Currell

T-Bolts!!!!!!!!! Could not get my Max-H to run a good 4-2-4, installed a T-Bolt and now it runs perfect.

>BTW, there's no particular rule about how much nitro you can
>use with a given heat range plug - it depends on a lot more
>than just the nitro.
>> Brett
>
>...and those other variables are?
>
>I remember Mr. Aldrich specifying that the TB 4S plug was
>not a good choice, IHO, for fuels over 15% nitro. Since he
>forgot more than I'll ever know about model engines I think
>I'll trust what he had to say.
>
>I'm still eager to see your opinion though...I don't
>consider you to be dumb as a post by any means either.

Compression ratio, plug depth, head shape, prop diameter/pitch, rpm, and on and on. In specific situations, 15% nitro might be all you can run. But not in general, and particularly not in low-compression stunt engines. Never mind that "hot" and "cold" are relative terms - what Rossi considers a "hot" plug might not what McCoy considers "hot" and might not be what OS considers "hot".

The only way to tell is to try it and see. George's advice is certainly safe enough, of course. But I've run .45 stunt motors with Rossi "Extra Hot" ("never use in motori larger than 2,5 cc!") plugs and 35% nitro with no indication of pre-ignition or frequently blowing them. And in fact in one case it still wasn't hot enough.

BTW - "hot" and "cold" generally refer to the ability to store heat, not anything to do with how hot the element gets/glows when you hook it to a battery. Of course, it does have something to do with how hot the element gets/glows with the battery off.

Brett,

I have been using the Fox RC plugs I got from Len, more than a year ago.

But there is a Made in Brazil plug called "CB" that is darn good.

The filaments are made of a Rhodium-Platinum alloy, and thay last

forever.

The only problem is that they are hard to get. The owner of CB

micromechanics is a friend of mine, and he sold me an excelent CB .46

Stunt engne for half price - 35 bucks - but the doggone thing arrived at

my mailbox with no plug and a note saying "I'm sorry, Ion, outta

plugs!"

If I can get my hands on a couple of hot cb plugs I'd be happy to mail

you one.

Dan, first time I took the Mutant Magnum out, I fired it off, it ran ok for about 30 seconds and quit. Restarted, it ran another 30 seconds and quit. Hmmmmm. I put in a new Thunderbolt with idle bar, noted that the original was a T-bolt without idle bar, it then ran fine, and it's still running on the same glowplug. You might want to try the T-Bolt 4 stroke plug, as it doesn't have an idle bar. I've only run them in the 2Star .60bb, and it's been sweet. Steve

Steve,

When purchasing the Mutant, you erred in not asking for a demonstration, relying instead upon my good character.

There did not appear to be any need whatsoever to supply you with a plug that actually worked. Or a clean fuel filter. Or a tool suitable for removal of the muffler. Or a set of lines. Or a gallon of fuel.

Yeah, the truth is that either I screwed up or the wrong plug got swapped into that motor, albeit well in advance of prepping it for sale. At least it appears as if I checked to see the plug lit up and smiled at me. As we hear all of the time at the Arcey Feeuld, that alone indicates the plug is working, simply cannot be the problem. Come to think of it, I have heard the same statement when out flying CL.

I will definitely be trying the T-bolt four-stroke piece.

I owe you a glow plug.

>I have been using the Fox RC plugs I got from Len, more than
>a year ago.

I have run Fox plugs at times in the past with good results - if you happen to get a good one. All too often they aren't good right out of the package - they glow, but the engine runs absolutely terrible. Far, far lower yield than any of the major brands (Glo-Devil, Thunderbolt, McCoy, OS, Enya, etc). Given that they aren't any cheaper than the others, and they are nothing to write home about in terms of run quality at the best of times, I just don't care to run them. There are those who swear by Fox plugs, and have good results, but I guess that's just the way it goes.

I might also add that there is a common thought, promulgated by some reworkers, that the Fox STD Short is "hotter" than all the others. They may work better than some other plugs in some circumstances, but In general they don't seem to be nearly as able to run the same with the battery on and off, and in most circumstances I have found they gave up a noticable amount of power compared to the more ordinary plugs. And the plug depth is wrong for most engines - because they are *short*.

The one plug I recommend that everyone avoid for stunt is the Rossi. They are very well made, and have lots of power. But after Ted's little problem at the '92 NATs, and numerous other similar flame-outs that seem to be reasonably repeatable. I just won't use them, and don't recommend them. They are very expensive, too.

Thunderbolt 4-cycle and R/C plugs work very well, are very consistent, are readily available, and reasonably cheap (although supply/demand seems to have raised their price since PW first discovered them at 79 cents a piece).

>I use the 4-stroke plug exclusively. It's probably as hot as
>it gets. BTW, there's no particular rule about how much
>nitro you can use with a given heat range plug - it depends
>on a lot more than just the nitro.

The T-Bolt is not as hot as the OS Max F-plug (at least that is what I have seen). The OS Max is actually almost too hot. Doug was running the OS Max when he flew in the Top Five in 2002. I think he is still running them in his PA 65.

The YS plug is the SAME PLUG as the OS Max F. Can be had for $5.00 from Central Hobbies.

The Sonictronic F-plug is also equivalent to the OS Max F.

I pretty much stay to the OS Max, YS, and Sonictronic for 4 cycles.

Is there a way to check a plug for it's heat range...like a meter that would measure the resistance or whatever needs to be checked? It would be nice to have a plug chart of all the different brands and how they compare to each other.

Bill P

Bill,

I've been told by a glow plug manufacturer that a glow plug's heat range is primarily determined by the platinum alloy mix (rhodium, iridium, etc.), alloy %, wire diameter and size of the plug chamber. To attempt to determine the range with a resistance measurement would probably be misleading.

Fred

Was this Al Kelly? Yup, he told me the same thing. I can't recall all the details, but the "heat" of a plug is based on how reactive the alloy is to the methanol in the fuel, and not due to the conduction of heat away from the tip of the plug, as it is in automotive spark plugs. The hotter a plug, the sooner it fires in the compression cycle, and therefore the more "advanced" the ignition timing is. Of course, the amount of nitro and the compression ratio of the engine also control the ignition timing.

Al said that the really cold plugs usually have some tungsten in the alloy, which was put in there to make the elements tough. Unfortunately, the tungsten also dims the fire quite a bit (which is why the plugs are cold - not on purpose, but as a necessary evil), so it can't be used in RC plugs. The various platinum group elements also have different characteristics - palladium is actually cheaper than platinum, and is often used to bring down the cost, at the expense of something (can't remember what), while irridium is ulta-expensive, and makes the plug really good, and is very rarely used (there was some legendary plug in the past that used some in the alloy, again, you'll have to ask Al). I think Al said Rhodium is used a lot in RC plugs because it helps the engine idle reliably.

>Was this Al Kelly? Yup, he told me the same thing. I can't
>recall all the details, but the "heat" of a plug is based on
>how reactive the alloy is to the methanol in the fuel, and
>not due to the conduction of heat away from the tip of the
>plug, as it is in automotive spark plugs. The hotter a plug,
>the sooner it fires in the compression cycle, and therefore
>the more "advanced" the ignition timing is. Of course, the
>amount of nitro and the compression ratio of the engine also
>control the ignition timing.
>

The alloy is a factor *in addition to*, not *instead of*, the heat storage ability.

I think the point to this is that "heat range" means different things in a model glow engine's glow plug than it does in an automotive spark plug. In an automobile engine, ignition timing is NOT controlled by the plug - a hot plug and a cold plug behave exactly the same when it comes to ignition timing. In this case, the heat range of a plug refers to its ability to conduct heat away from the engine. Use too cold a plug, though, and carbon builds up on the electrodes. Use too hot a plug, and the electrodes start eroding and failing way before their time (or worse, you can poke holes in pistons, as a couple of friends who owned a Chevy Vega found out when a mechanic put the wrong plugs in and the thing stopped running a week afterwards..).

In a model glow engine, when we say "hot plug" or "cold plug", it's got nothing to do with the above. What we mean is that a "hot" plug gives advanced ignition when compared to a "cold" plug. This may or may not have anything to do with the heat conduction ability of the plug (and it does, from what I've heard, have a great deal to do with the alloy used), BUT the "heat range" of the plug has nothing to do, directly speaking, with heat conduction, as it does in automotive spark plugs.

Iskandar,

Yes, it was Al.

Fred

This is fairly well covered in Harry Higley's book "All About Engines". You might find the book at your LHS, or available from Tower Hobby. It's a good book, recommended by websites everywhere! http://www.nwskyraiders.com/beginners.html Steve

I understand what you guys are saying but I'm trying to find a way to benchmark one plug against another without trying them. Not so much as the "whys or hows" of reactive chemistry but more "this one is hot or cold". It would be nice to know I could substitute brand X for brand Y to get the same performance.

My seat of the pants tests with plugs show wire size generally makes a difference no matter the brand and that's why resistance was mentioned...but only as a stab in the dark. I check plugs under a scope (scopes are great for engine work!)and find different wire diameters generally reflect hot/cold running differences. Whether technicaly correct or not, most of us use hot/cold as the way we select plugs and know how that relates to our engine runs. There must be a way to lab test plugs but I suppose it is expensive.

Quantifying something like this would be pretty hard to do except in broad generalizations. How does one measure heat range? I suspect that one plug might act slightly hotter with respect to another plug in in one engine and slightly colder in another, and scatter in the data would be pretty significant, even with plugs of the same brand and model.

It is cool to see the way that Thunderbolts have caught on. I started using them about 20 years ago when we got them from Hobby Shack and thought we were the cleverest fliers around in doing so. They were dirt cheap and worked as well or better than anything else (I think we initially paid about 50 cents a plug). Cost was a factor in the days when we changed a plug every combat match. I still use mostly T-bolts in all my airplanes, and have never had a complaint about them. I use the idle-bar plugs in the stunters, and the standard in combat and racing planes.

--jt

Why is it when a post like this has a certain number of poeple reply with a message the messages no longer appear? You have to click on them to read them.

>Why is it when a post like this has a certain number of
>poeple reply with a message the messages no longer appear?
>You have to click on them to read them.

Good question. We could have put this in the support forum, but I will answer it here.

You are obviously choosing to view the forum in linear mode. I view it in the expanded, or threaded mode. You can change the way you view it by clicking on the little + or - sign in the left side of the dark blue bar at the top of the forum.

There is an administrator setting available to me at which I can set "autosensing starts here." I have arbitrarily set this at 30. That means that when you choose to view the forum in linear mode, once any particular thread reaches 30 or more replies, then it will automatically switch to the threaded mode for that particular thread which reduces down load time. You can, however, simply click on "view all" at the very top next to the originator's post and it will still display all of the responses in that thread whether or not it has exceeded the 30 limit. So the option is still there for you. You can also do this at any time while viewing in the expanded mode, which is what I often do when there are a large number of responses that I haven't looked at.

LAST EDITED ON Dec-09-03 AT 08:53 PM (CST)
 
I clicked on the "+". Very interesting - I didn't know you could do that.

I think what Gary's talking about is that, suddenly, you don't see the entire thread laid out in front of you, and must view messages one at a time (tedious horribillus). What he needs to do is, when going into a long thread, click on "View All" instead of the title of the thread. If he gets into the thread without using "View All", there's a little "View All" link up towards the top somewhere (I think in the list of messages in the thread).

After you post a message, all of a sudden, you'll find yourself out of "View All" mode - same advice. There's a "View All" link up at the top of the message listings.

>I clicked on the "+". Very interesting - I didn't know you
>could do that.
>
>I think what Gary's talking about is that, suddenly, you
>don't see the entire thread laid out in front of you, and
>must view messages one at a time (tedious horribillus). What
>he needs to do is, when going into a long thread, click on
>"View All" instead of the title of the thread. If he gets
>into the thread without using "View All", there's a little
>"View All" link up towards the top somewhere (I think in the
>list of messages in the thread).
>
>After you post a message, all of a sudden, you'll find
>yourself out of "View All" mode - same advice. There's a
>"View All" link up at the top of the message listings.

I guess we are off the subject, but what else is new? The fact that you can view the forum in different ways is what drew me to this software in the first place. It looks like it is going to be after Christmas before I get a chance to finish up the php software, but that one will give us three choices in how to view it. UBB (linear) DCF (which is the expanded mode) or "Classic". You remember Classic, don't you Isky?

Anyway, to each his own. Choose the way you wish to view the threads. You can also choose to have the new flags shown every time you return, or only after you click on the "Mark" icon on the top (which will appear there only if you choose that option in your user menu).

More features: Read the FAQs.