Turbo Plugs How To
07-24-2006, 03:42 PM
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RE: Turbo Plugs How To
Andy,
Good work up there. But I have to be honest even with owning a milling machine and lathe and I love to to mess with stuff it's just to easy to buy a Galbreath Head and Nelson plug for my Cox/Norvel .049/.061's. At $15/$9.00 a plug those Turbos are right upthere with the factory Cox heads and was that not the reason to get away from them to start with...the price.
Later,
Tim
Good work up there. But I have to be honest even with owning a milling machine and lathe and I love to to mess with stuff it's just to easy to buy a Galbreath Head and Nelson plug for my Cox/Norvel .049/.061's. At $15/$9.00 a plug those Turbos are right upthere with the factory Cox heads and was that not the reason to get away from them to start with...the price.
Later,
Tim
07-24-2006, 04:06 PM
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RE: Turbo Plugs How To
Sounds good Stewart, [8D]
I'll first run it again, as is, and then make the mods and test. Same fuel, engine, prop and same afternoon ought to give an accurate comparison.
I'll first run it again, as is, and then make the mods and test. Same fuel, engine, prop and same afternoon ought to give an accurate comparison.
07-24-2006, 04:51 PM
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RE: Turbo Plugs How To
ORIGINAL: Tim Wiltse-RCU
Andy,
Good work up there. But I have to be honest even with owning a milling machine and lathe and I love to to mess with stuff it's just to easy to buy a Galbreath Head and Nelson plug for my Cox/Norvel .049/.061's. At $15/$9.00 a plug those Turbos are right up there with the factory Cox heads and was that not the reason to get away from them to start with...the price.
Later,
Tim
Andy,
Good work up there. But I have to be honest even with owning a milling machine and lathe and I love to to mess with stuff it's just to easy to buy a Galbreath Head and Nelson plug for my Cox/Norvel .049/.061's. At $15/$9.00 a plug those Turbos are right up there with the factory Cox heads and was that not the reason to get away from them to start with...the price.
Later,
Tim
Hi Tim,
Yes, you make a good point. Unfortunately I made an assumption that the turbos would be reasonably priced. More maybe by a bit, but not by that much.
Note that from RC Planet at http://www.rcplanet.com/glow_plugs_18183_ctg.htm they list a standard, OS #8 plug at 4.99. It would seem to me that, on CNC automated equipment, a turbo ought not to be that much more expensive to make, if at all. Do the OS turbos have a solid platinum element and the #8 a plated element? This is the only way I can think of that would justify such an elevated price. Is it volume of production? Seems to me that there are a LOT of car guys around so I don't know.
Price was one thing but so was/is availability. If Nelson ever stops making plugs/retires/wins the lottery,,, Plus, making your own allows you to have one for your .074 interchangeable with your Brodak/CS. Plus making your own allows you to play with combustion chamber shapes. That's one reason why I did it. Turbos are made by a variety of companies with a large heat range (Rossi) and you can get them at your LHS. Not sure you can for Nelson plugs.
Classicalgas mentioned that he does turbo heads for older engines that provide an extra free 400 rpm and up to 1000 for modern engines. Not bad,, and so why would the industry not standardize on turbos?? I now will be making turbo inserts for my Norvel .15, .25 and .40. An extra thou RPM would be huge.
So if Sig/Norvel or aftermarket made turbo inserts, mass produced at a good price, would not this be worth the effort?
And, well, it was a lot of fun doing the thing, learning new skills and sharing,,,
07-24-2006, 09:44 PM
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RE: Turbo Plugs How To
ORIGINAL: SGC
" I can`t believe the price . almost $15.00 each. "
Ye makes Nelson plugs at $4 look good hey.
Dave,
Your racer ? does it have dome topped pistons ? From my 2st experiance hemi combustion chambers work best with dome topped pistons, were the piston top has a smaller radius than the combustion chamber , this gives a natural progressive sqish band and makes the motor not prone to detonation. Oh and how many souveneres do you have hanging in your shed ? Full combustion detonation makes nice 10-30mm holes dead centre in piston crowns hey
Stewart
" I can`t believe the price . almost $15.00 each. "
Ye makes Nelson plugs at $4 look good hey.
Dave,
Your racer ? does it have dome topped pistons ? From my 2st experiance hemi combustion chambers work best with dome topped pistons, were the piston top has a smaller radius than the combustion chamber , this gives a natural progressive sqish band and makes the motor not prone to detonation. Oh and how many souveneres do you have hanging in your shed ? Full combustion detonation makes nice 10-30mm holes dead centre in piston crowns hey
Stewart
07-24-2006, 10:02 PM
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RE: Turbo Plugs How To
Andy, I`m Embarassed ,I mentioned this Book of mine ,and I can not find it .It kind of upsets me, because I paid $60.00 for it,and it is worth every penny.Now I`m wondering where it is.When I find it, I`ll definately send you some info.kind of feel foolish for mentioning it now..Sorry about that..Any how, I did order, 2 of those OS.Plugs if they last, 2X as long,or more, as a Norvel button, Then they`ll pay for themselves.But,Wow[X(] for the 2 of those I`m half way, to a new 0.061" ......... Dave
07-24-2006, 10:37 PM
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RE: Turbo Plugs How To
Gosh Dave, no problem at all. I know how you feel. Sometimes I post a number I'm dead sure of only to be reminded by someone what I said way back,,, Computers have LONG memories. The squish band thing just happened by accident when I made up a diesel head with a bit of a smaller CP. Seemed to run better and Stewart has given me some ideas to try and improve on the grossly smaller CP unit I made to test. I generally just try something and if it works, I'm happy. And if I find out WHY it works, that's just a bonus.
But anyway, me embarrassed too about the price of turbos. [:@] A search though, can yield sources much cheaper but if I could, I'd buy nothing but OS. Do they make a diesel?
From Stewart,
Andy,
i found theses tubo plug suppliers first 1 has set of 3 for US$16 :- http://www.ashfordhobby.com/prod270.htm
http://www.rcplanet.com/glow_plugs_18183_ctg.htm
http://www.hobbyclub.com/RossiEngines.htm <----------- good price on Rossi tubo plugs
N these on Ebay - http://cgi.ebay.com/ws/eBayISAPI.dll...SI_PR4_PCN_BIX
Cheers
Stewart
But anyway, me embarrassed too about the price of turbos. [:@] A search though, can yield sources much cheaper but if I could, I'd buy nothing but OS. Do they make a diesel?
From Stewart,
Andy,
i found theses tubo plug suppliers first 1 has set of 3 for US$16 :- http://www.ashfordhobby.com/prod270.htm
http://www.rcplanet.com/glow_plugs_18183_ctg.htm
http://www.hobbyclub.com/RossiEngines.htm <----------- good price on Rossi tubo plugs
N these on Ebay - http://cgi.ebay.com/ws/eBayISAPI.dll...SI_PR4_PCN_BIX
Cheers
Stewart
07-25-2006, 12:42 AM
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RE: Turbo Plugs How To
I have to hand it to ya your persistant ..I`ll give the OS plugs a shot,and if they last a good long time ,and meet ,or beat ,the factory stuff ..I`m a happy guy then too..They mostl likely will take some punishment, before they become junk..If they outlast, a factory original Plug ,3 to 1 ,then they become economical too..
07-25-2006, 01:40 AM
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RE: Turbo Plugs How To
Hi Dave,
More like obsessed.
Turbo head and adaptor on the way to you and if you get the urge, here's a source for the tap http://www1.mscdirect.com/CGI/NNSRIT...2459&PMCTLG=00 and look at the price. I paid nearly 30 bucks for mine. [X(] This one isn't a bottoming but a little grinding will take care of that.
Credit for this tip goes to classicalgas and injunnut1 who also linked a possible source for a die for the threads on the .020
And that reminds me. Not to beat it to death but what to do when your last .09 plug burns out? It WILL respond well to a stock plug installed in an old head but imagine if the turbo gives you an extra thou RPM? Neat.
Well now, I've got a throttled .09 that could be smoother on the top end with a better transition although it's not bad now. Here's where you can experiment with adaptors with various combustion chamber shapes, squish band etc. I think I'll make a trumpet head for it right soon.
More like obsessed.
Turbo head and adaptor on the way to you and if you get the urge, here's a source for the tap http://www1.mscdirect.com/CGI/NNSRIT...2459&PMCTLG=00 and look at the price. I paid nearly 30 bucks for mine. [X(] This one isn't a bottoming but a little grinding will take care of that.
Credit for this tip goes to classicalgas and injunnut1 who also linked a possible source for a die for the threads on the .020
And that reminds me. Not to beat it to death but what to do when your last .09 plug burns out? It WILL respond well to a stock plug installed in an old head but imagine if the turbo gives you an extra thou RPM? Neat.
Well now, I've got a throttled .09 that could be smoother on the top end with a better transition although it's not bad now. Here's where you can experiment with adaptors with various combustion chamber shapes, squish band etc. I think I'll make a trumpet head for it right soon.
07-25-2006, 11:39 PM
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RE: Turbo Plugs How To
Classicalgas, on another thread was kind enough to illustrate how he made inserts to accommodate Nelson plugs for Cox .020 engines. I have Nelson plugs and adaptors and Cox .02 heads and there is NO way this can be done,,, or so I thought. But he found a way and it's nothing short of brilliant.
But,,,
This is another reason for considering the turbos. There was a TD .15, I know, but the biggest practically available engine is the TD .09 and modifying the head to accept a turbo is a cinch.Plus, another old head was bored out to take inserts that are going to sport various combustion chamber shapes. It isn't clear in the pics but the one, last good plug I have is a high compression unit with a shallow trumpet shape. The only other .09 plug I had to do the conversion with, was a stock, standard compression head.
Good enough, but wait Martha, it can also be done to an .020 head. It's tight with only a few threads to engage the plug but it works. I've deliberately over tightened the plug trying to strip the threads and no problem. As you can see, this takes out, entirely, the top fin where the wrench slots are. This required milling the sides down to take an .020 wrench. With care, I'm sure that this could also be done free-hand with a fine file.
This is going to allow experimenting with various heat ranges to see if top end and throttling can be improved.
Next up is the TD .010. THAT is going to look ridiculous, the plug alone will up the weight of the engine some 20% but what the heck. Might learn something.
But,,,
This is another reason for considering the turbos. There was a TD .15, I know, but the biggest practically available engine is the TD .09 and modifying the head to accept a turbo is a cinch.Plus, another old head was bored out to take inserts that are going to sport various combustion chamber shapes. It isn't clear in the pics but the one, last good plug I have is a high compression unit with a shallow trumpet shape. The only other .09 plug I had to do the conversion with, was a stock, standard compression head.
Good enough, but wait Martha, it can also be done to an .020 head. It's tight with only a few threads to engage the plug but it works. I've deliberately over tightened the plug trying to strip the threads and no problem. As you can see, this takes out, entirely, the top fin where the wrench slots are. This required milling the sides down to take an .020 wrench. With care, I'm sure that this could also be done free-hand with a fine file.
This is going to allow experimenting with various heat ranges to see if top end and throttling can be improved.
Next up is the TD .010. THAT is going to look ridiculous, the plug alone will up the weight of the engine some 20% but what the heck. Might learn something.
07-26-2006, 12:13 AM
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RE: Turbo Plugs How To
Go here to find the full range of currently available Rossi Turbo Plugs, fourteen in all and in every heat range too ..... but the best part is the $$price$$, most are less than $5.00 USA each !!!!!!!!!!!!!! BTW, a person might consider shouting out to the CAR guys about which Turbo Plugs are best and why ...... after all, it is the big surge in Nitro Car Racing that is responsible for the new HOT engine set-ups and the Turbo Plugs, I think? Andy, have you ever considered the OS CVR .18 car engine to play with, it is currently on sale at Tower Hobbies, and even cheaper is the Boat version for only $85.00 currently. See photo of a couple (one on right is the CVR .18, the other is the top of line TZ .18 rear exhaust) OS .18 Car engines that I have modified for aircraft use, both will get the Nelson head conversions.
http://www.planethobby.com/home.php?cat=23
Here is the link to the OS .18 CVR Marine engine currently on sale, a real steal at $85.00, less than half price! Easily converted to aircraft use, including the necessary carburetor conversion too. Remember too that this engine is stuffed into a .12 size c/case, it will bolt in where an OS Max .10FP once was .... takes the same size muffler pattern also!
http://www2.towerhobbies.com/cgi-bin...?&I=LXKGR2&P=7
http://www.planethobby.com/home.php?cat=23
Here is the link to the OS .18 CVR Marine engine currently on sale, a real steal at $85.00, less than half price! Easily converted to aircraft use, including the necessary carburetor conversion too. Remember too that this engine is stuffed into a .12 size c/case, it will bolt in where an OS Max .10FP once was .... takes the same size muffler pattern also!
http://www2.towerhobbies.com/cgi-bin...?&I=LXKGR2&P=7
07-26-2006, 01:12 AM
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RE: Turbo Plugs How To
Hi Injunnut1,
Many thanks,
And Rossi's are a quality, known brand,, what more could you ask? Neat.
You're right about the car guys,, these things were invented for them. I'm amazed that given their advantages, all engines aren't made to take them.
I'd consider the OS .18 but I'm afraid that my current interest in engines that fly something are diesels swinging big props kinda slow. The car engines, I would think, are meant to run really, really fast. I mean REALLY fast. Those guys want to WIN.
But if the budget allowed, I'd really consider one for conversion to diesel.
And here's a thought, wonder if anyone's tried turbos on four strokes.
Hmm, might be time to wander over to some of the other forums.
Many thanks,
And Rossi's are a quality, known brand,, what more could you ask? Neat.
You're right about the car guys,, these things were invented for them. I'm amazed that given their advantages, all engines aren't made to take them.
I'd consider the OS .18 but I'm afraid that my current interest in engines that fly something are diesels swinging big props kinda slow. The car engines, I would think, are meant to run really, really fast. I mean REALLY fast. Those guys want to WIN.
But if the budget allowed, I'd really consider one for conversion to diesel.
And here's a thought, wonder if anyone's tried turbos on four strokes.
Hmm, might be time to wander over to some of the other forums.
07-26-2006, 11:26 PM
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RE: Turbo Plugs How To
To convert the Car engine you must obviously turn the head down, plus you must relocate the NVA on the carb ..... both of these operations are pretty much standard procedure to your own particular liking. I have not converted the Marine engine yet, but am seriously considering purchasing one soon while they are on sale at the LOW price of only $85.00!! I can post photo of a modified carb if you like? You have already seen the two Car Engine head mods I reckon?
When you ask about numbers, are you asking about performance figures, or timing numbers with-in the particular engine? I have not done any test runs yet, am waiting on cooler weather ..... the weather is torturous (Pure Hell) here in Florida this time of year and the older I get, the more HOT weather bothers me!
When you ask about numbers, are you asking about performance figures, or timing numbers with-in the particular engine? I have not done any test runs yet, am waiting on cooler weather ..... the weather is torturous (Pure Hell) here in Florida this time of year and the older I get, the more HOT weather bothers me!
ORIGINAL: Sneasle
interesting. Do you have any numbers on that conversion or info on how to actually do the conversion?
interesting. Do you have any numbers on that conversion or info on how to actually do the conversion?
07-28-2006, 02:02 AM
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RE: Turbo Plugs How To
ORIGINAL: injunnut1
<snip>
I have not done any test runs yet, am waiting on cooler weather ..... the weather is torturous (Pure Hell) here in Florida this time of year and the older I get, the more HOT weather bothers me!
<snip>
<snip>
I have not done any test runs yet, am waiting on cooler weather ..... the weather is torturous (Pure Hell) here in Florida this time of year and the older I get, the more HOT weather bothers me!
<snip>
al
PS It's even hotter here in Louisiana.
08-16-2006, 11:20 AM
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RE: Turbo Plugs How To
I think we may be using the terms turbo plugs and Nelson Plug interchangeably. I believe that Andy has modified a Cox 0.020 head to accept a Turbo Plug and I would agree that there is sufficient material in the stock plug for that mod. My approach was to make an insert that would use the Nelson plug which is considerably larger in diameter than the turbo plugs and less than 1/2 the price. In making an insert from aluminum I found that there was not enough material between the major diameter of the Nelson plug threads and the minor diameter of the threads in the Cox cylinder for structural integrity. Something like 0.037!QUOT! is the difference in diameters. For this reason I went to steel for the insert which worked fine from a strength view point but I am still working on getting it to run equal to the stock Cox plug. Believe I am a bit too low on compression and need to do more testing by removing material from the bottom of the insert. May take a few weeks as I stuck my hand in a prop at the NATS and need to let the skin graft heal a bit or I will probably screw it up.
If anyone out there has a good handle on the volume of the Cox 0.020 combustion chamber when set up for say 50% nitro I would be interested. Also if I get this all working I may run a batch for sale. Lots of free flighters use the 020 and all are very unhappy about the situation with Cox. They tend to use a lot of 65% Aerodyne fuel which can really eat up plugs.
Thanks
If anyone out there has a good handle on the volume of the Cox 0.020 combustion chamber when set up for say 50% nitro I would be interested. Also if I get this all working I may run a batch for sale. Lots of free flighters use the 020 and all are very unhappy about the situation with Cox. They tend to use a lot of 65% Aerodyne fuel which can really eat up plugs.
Thanks
08-17-2006, 09:09 AM
#41
RE: Turbo Plugs How To
I have been lurking about here at rcu a bit lately.
I didn`t see this untill today, but Dave, if you need some O.S turbo plugs I can get them a lot cheaper here in Japan- the rossi ones are slightly more expensive here. I think it would only be about $2 postage to Canada.
Stefan
I didn`t see this untill today, but Dave, if you need some O.S turbo plugs I can get them a lot cheaper here in Japan- the rossi ones are slightly more expensive here. I think it would only be about $2 postage to Canada.
Stefan
08-17-2006, 03:52 PM
#42
RE: Turbo Plugs How To
Andy et al:
The LHS here that deals in cars has Turbo plugs for 7.95-9.95 and that is $CDN, for various flavours and heat ranges. In looking at them and the issue of compression in 020 I had another brain fade or some other word. If one is using a lathe, could not the outer diameter of a Turbo plug be turned down and rethreaded? The face distance across the 60 degree seat is way larger than it needs to be for an 020. Reducing the diameter and thus the seat face width would allow the plug to fit with lots of meat left on the 020 plug casing. As it is an external thread on the plug, the rethread of the Plug would be straight forward. The internal thread on the 020 case/insert would now be smaller and could be chosen based on availability of the proper tap. This might result in having a higher compression plug/head combination as well.
How much material is there between the element cavity and the threads of the turbo plug or the Nelson Plug? This would be the starting point for thread size and tap availability selection. Would need to scarifice one or two by turning them to destruction!
Then if a practical soultion is devised, maybe Nelson would be willing to make his plugs in a batch with a smaller diameter and revised seat width and thread. If the current Nelson plugs are made on CNC multi tool automatic machines, and it is inconceivable that they are not, then some reprogramming and test would be all that is required. The machining time would be a few seconds longer, the tooling may have to be slightly different for the different thread diameter, but material cost and packaging etc would be the same. And on an automatic chucker that change of tooling is not a great programming step.
The big wrinkle in manufacturing is the process of installing the element and sealing the stem. If that process has to change a great deal then this is not doable. Then a process of re-machineing finished plugs to suit would be the only viable route.
Anyway just some ideas to kick around for those with the lathes and need for 020 plugs.
Jim H
The LHS here that deals in cars has Turbo plugs for 7.95-9.95 and that is $CDN, for various flavours and heat ranges. In looking at them and the issue of compression in 020 I had another brain fade or some other word. If one is using a lathe, could not the outer diameter of a Turbo plug be turned down and rethreaded? The face distance across the 60 degree seat is way larger than it needs to be for an 020. Reducing the diameter and thus the seat face width would allow the plug to fit with lots of meat left on the 020 plug casing. As it is an external thread on the plug, the rethread of the Plug would be straight forward. The internal thread on the 020 case/insert would now be smaller and could be chosen based on availability of the proper tap. This might result in having a higher compression plug/head combination as well.
How much material is there between the element cavity and the threads of the turbo plug or the Nelson Plug? This would be the starting point for thread size and tap availability selection. Would need to scarifice one or two by turning them to destruction!
Then if a practical soultion is devised, maybe Nelson would be willing to make his plugs in a batch with a smaller diameter and revised seat width and thread. If the current Nelson plugs are made on CNC multi tool automatic machines, and it is inconceivable that they are not, then some reprogramming and test would be all that is required. The machining time would be a few seconds longer, the tooling may have to be slightly different for the different thread diameter, but material cost and packaging etc would be the same. And on an automatic chucker that change of tooling is not a great programming step.
The big wrinkle in manufacturing is the process of installing the element and sealing the stem. If that process has to change a great deal then this is not doable. Then a process of re-machineing finished plugs to suit would be the only viable route.
Anyway just some ideas to kick around for those with the lathes and need for 020 plugs.
Jim H
08-17-2006, 11:25 PM
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RE: Turbo Plugs How To
ORIGINAL: small_rcer
Andy et al:
The LHS here that deals in cars has Turbo plugs for 7.95-9.95 and that is $CDN, for various flavours and heat ranges. In looking at them and the issue of compression in 020 I had another brain fade or some other word. If one is using a lathe, could not the outer diameter of a Turbo plug be turned down and rethreaded? The face distance across the 60 degree seat is way larger than it needs to be for an 020. Reducing the diameter and thus the seat face width would allow the plug to fit with lots of meat left on the 020 plug casing. As it is an external thread on the plug, the rethread of the Plug would be straight forward. The internal thread on the 020 case/insert would now be smaller and could be chosen based on availability of the proper tap. This might result in having a higher compression plug/head combination as well.
How much material is there between the element cavity and the threads of the turbo plug or the Nelson Plug? This would be the starting point for thread size and tap availability selection. Would need to scarifice one or two by turning them to destruction!
Then if a practical soultion is devised, maybe Nelson would be willing to make his plugs in a batch with a smaller diameter and revised seat width and thread. If the current Nelson plugs are made on CNC multi tool automatic machines, and it is inconceivable that they are not, then some reprogramming and test would be all that is required. The machining time would be a few seconds longer, the tooling may have to be slightly different for the different thread diameter, but material cost and packaging etc would be the same. And on an automatic chucker that change of tooling is not a great programming step.
The big wrinkle in manufacturing is the process of installing the element and sealing the stem. If that process has to change a great deal then this is not doable. Then a process of re-machineing finished plugs to suit would be the only viable route.
Anyway just some ideas to kick around for those with the lathes and need for 020 plugs.
Jim H
Andy et al:
The LHS here that deals in cars has Turbo plugs for 7.95-9.95 and that is $CDN, for various flavours and heat ranges. In looking at them and the issue of compression in 020 I had another brain fade or some other word. If one is using a lathe, could not the outer diameter of a Turbo plug be turned down and rethreaded? The face distance across the 60 degree seat is way larger than it needs to be for an 020. Reducing the diameter and thus the seat face width would allow the plug to fit with lots of meat left on the 020 plug casing. As it is an external thread on the plug, the rethread of the Plug would be straight forward. The internal thread on the 020 case/insert would now be smaller and could be chosen based on availability of the proper tap. This might result in having a higher compression plug/head combination as well.
How much material is there between the element cavity and the threads of the turbo plug or the Nelson Plug? This would be the starting point for thread size and tap availability selection. Would need to scarifice one or two by turning them to destruction!
Then if a practical soultion is devised, maybe Nelson would be willing to make his plugs in a batch with a smaller diameter and revised seat width and thread. If the current Nelson plugs are made on CNC multi tool automatic machines, and it is inconceivable that they are not, then some reprogramming and test would be all that is required. The machining time would be a few seconds longer, the tooling may have to be slightly different for the different thread diameter, but material cost and packaging etc would be the same. And on an automatic chucker that change of tooling is not a great programming step.
The big wrinkle in manufacturing is the process of installing the element and sealing the stem. If that process has to change a great deal then this is not doable. Then a process of re-machineing finished plugs to suit would be the only viable route.
Anyway just some ideas to kick around for those with the lathes and need for 020 plugs.
Jim H
Hi Jim,
You're right in that the face diameter is larger than needed and may be interfering with getting a good compression ratio and/or combustion chamber shape. Recent runs on the head I made has shown problems. Low power and some throttling issues. A good idea about thread diameter but redoing a stock plug is fraught with problems. Specifically, getting the redo exactly square. There's no room for any tolerances whatever. If the whole assembly is not EXACTLY square, we have a poor seal and leakage.
Yes, if someone with the CNC equipment had the notion, it could be done, easily. The trouble is, will it pay. It HAS to pay, or it will never be done. We are a VERY small group and I'd venture to say, the RC .020 group is even that much smaller. MP Jets saw the writing on the wall and stopped making their great .06 engine and went electric.
Sad, spoken as a gearhead, but true.
One option would be to reface the seat on stock, turbo plugs but then we still run into the issue of getting it exactly square.
08-18-2006, 09:20 AM
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RE: Turbo Plugs How To
Anybody have a print for the .020 to standard Glow plug adaptor? I might be able to knock a few off on a weekend (depends on shopload).. they will be out of Ti6Al4V though, I'd rather break in and use existing material/tooling to get it done. I have the machine tools http://www.omcprecision.com/ , just gotta find the time. it looks like a <2 minute part a couple hundred could be knocked out in under a 12 pack.
08-18-2006, 04:23 PM
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RE: Turbo Plugs How To
ORIGINAL: cncswiss1
Anybody have a print for the .020 to standard Glow plug adaptor? I might be able to knock a few off on a weekend (depends on shopload).. they will be out of Ti6Al4V though, I'd rather break in and use existing material/tooling to get it done. I have the machine tools http://www.omcprecision.com/ , just gotta find the time. it looks like a <2 minute part a couple hundred could be knocked out in under a 12 pack.
Anybody have a print for the .020 to standard Glow plug adaptor? I might be able to knock a few off on a weekend (depends on shopload).. they will be out of Ti6Al4V though, I'd rather break in and use existing material/tooling to get it done. I have the machine tools http://www.omcprecision.com/ , just gotta find the time. it looks like a <2 minute part a couple hundred could be knocked out in under a 12 pack.
A standard glow plug will rob 1 to 1.5K off the top end. Not a good thing. That's the point of the turbo plug. On Norvels and Cox in .049/.06 sizes, no power loss is seen and in some cases, a gain can be had by playing with heat ranges to match the fuel you're using.
But even with a turbo, the .020 needs work. It appears to be CR related, just too busy with diesel right now to make it right. Maybe later.
IF you mean a standard turbo plug, I can send you the head as a sample, if you like. The outer thread size is a strange beast,,, .390 X 48 TPI UNS-3B
08-18-2006, 04:52 PM
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RE: Turbo Plugs How To
IF you mean a standard turbo plug, I can send you the head as a sample, if you like. The outer thread size is a strange beast,,, .390 X 48 TPI UNS-3B
with CNC and singlepoint tooling the thread will be no problem. I'd like to knock a few out for kicks. probably make them a tad taller to get more engagement.
08-18-2006, 05:13 PM
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RE: Turbo Plugs How To
How about waiting a bit till we work out the geometry. I am working on an insert for the 020 that will use the Nelson which if successful in performance will cut the cost of the plug to $4 which beats the turbo plug. Like Andy I just got a little free time to to doing some running.
Bob
Bob
08-18-2006, 09:29 PM
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RE: Turbo Plugs How To
ORIGINAL: cncswiss1
oops, yes turbo plug.. friday and all.[:@]
with CNC and singlepoint tooling the thread will be no problem. I'd like to knock a few out for kicks. probably make them a tad taller to get more engagement.
IF you mean a standard turbo plug, I can send you the head as a sample, if you like. The outer thread size is a strange beast,,, .390 X 48 TPI UNS-3B
with CNC and singlepoint tooling the thread will be no problem. I'd like to knock a few out for kicks. probably make them a tad taller to get more engagement.
I'm inclined to prefer the turbos because of availability and variety. Even Rossi's are only two bucks more from some sources. A sample waits, if you're willing.
And I suspect, as with TD .049 high compression heads, a trumpet shape on the inside may be the answer to getting high enough compression ratio. One could make this side a shade taller and a bit of experimental shaving could bring you right there in no time.
08-19-2006, 05:30 AM
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RE: Turbo Plugs How To
ORIGINAL: Japanman
I have been lurking about here at rcu a bit lately.
I didn`t see this untill today, but Dave, if you need some O.S turbo plugs I can get them a lot cheaper here in Japan- the rossi ones are slightly more expensive here. I think it would only be about $2 postage to Canada.
Stefan
I have been lurking about here at rcu a bit lately.
I didn`t see this untill today, but Dave, if you need some O.S turbo plugs I can get them a lot cheaper here in Japan- the rossi ones are slightly more expensive here. I think it would only be about $2 postage to Canada.
Stefan
Hi Stefan..Thanks for the offer..I haven`t tried Andys insert yet but I do have a couple of the O.S turbo plugs now .I mentioned how expensive they are here..In the meantime maybe you could check into the price of those Glow plugs in Japan,for my curiousity..I think I`ll also check into alternative brands and test those too.If things show that the O.S. parts are best,I`ll stick with them..Would you, be able to tell me ,if the O.S. plugs ,last any longer, or are more durable, than any of the other brands..