Merlin inserts?

Kamtechnic is also a source

63expert wrote:Kamtechnic is also a source

+1 on that.

After some searching, I found Kamtechnic. All I see on that site are heads that call for an OS plug, no inserts.

I also see that MECOA has K&B and Norvel type inserts.

That is the right head. Not an insert. It takes a Turbo style plug. Better power than the MECOA ones that use a standard 1/4" plug. Similar to the Cox TD heads in power. Arguably a bit more.

Aero,
I know when I got my first Norvel .061, I tried a Cox head on it. It worked. Then I got an AP .061, and successfully tried a Cox head on it. Shortly after, I bought a package of Merlin plugs and the head/adapter. And I seem to remember noticing Merlin plugs fit the Norvel and AP engines, as well as my Cox engines. All those inserts worked fairly interchangeably on Cox .049s, and the Norvel/AP .061s. No combination was flight tested, but bench tested. I do remember having to make head gasket adjustments...but no details.

Mecoa's website indicates their insert will NOT fit the AP adapter. The adapter's hole is to small in diameter. So worst case is you'll need a Norvel adapter, or access to a drill press to drill out your Merlin adapter.

I also have Norvel .074 engines. They have larger inserts, so no interchangeability with th littler engines there.

So, if you think you would try a Mecoa insert in place of the Merlins, then I would gladly go find my inserts and do some measuring and comparing of the Merlins, Norvels and apparently narrower APs. I may do anyway, since this thread caused.me to go check their offering.
Is this a perfect answer? Nope, but since Mecoa is marketing theirs as .061 compatible, this may be the next best thing to Merlins for our .049/.061 engines.

Let me know you want the data...then I'll prioritize the check.

944_Jim wrote:Aero,
I know when I got my first Norvel .061, I tried a Cox head on it. It worked. Then I got an AP .061, and successfully tried a Cox head on it. Shortly after, I bought a package of Merlin plugs and the head/adapter. And I seem to remember noticing Merlin plugs fit the Norvel and AP engines, as well as my Cox engines. All those inserts worked fairly interchangeably on Cox .049s, and the Norvel/AP .061s. No combination was flight tested, but bench tested. I do remember having to make head gasket adjustments...but no details.

Mecoa's website indicates their insert will NOT fit the AP adapter. The adapter's hole is to small in diameter. So worst case is you'll need a Norvel adapter, or access to a drill press to drill out your Merlin adapter.

I also have Norvel .074 engines. They have larger inserts, so no interchangeability with th littler engines there.

So, if you think you would try a Mecoa insert in place of the Merlins, then I would gladly go find my inserts and do some measuring and comparing of the Merlins, Norvels and apparently narrower APs. I may do anyway, since this thread caused.me to go check their offering.
Is this a perfect answer? Nope, but since Mecoa is marketing theirs as .061 compatible, this may be the next best thing to Merlins for our .049/.061 engines.

Let me know you want the data...then I'll prioritize the check.

944_Jim, I would appreciate you doing that!

I only have 3 maybe 4 extra Cox heads left, 2 Norvel inserts and 2 Merlin inserts left.
I was wanting to find replacements and the roads are looking kinda narrow now.

Glad to get all the input!

This is not the place of commercials here, but the reason I bought a couple of Kamtechnik turbo heads was their interchangeability with all COX049 heads (and heads of Norvel 051/061 engines, which I have but do not use) at way higher engine output than with the stock high-compression COX head, or with the Merlin insert plug,  PLUS most importantly, for their use of common - not the limited availability Nelson- turbo plugs (not just OS), which are sold in most hobby shops. So Kamtechnik head="eternal" availability of glow heads for my COX 049/050/051 engines.

balogh wrote:This is not the place of commercials here, but the reason I bought a couple of Kamtechnik turbo heads was their interchangeability with all COX049 heads (and heads of Norvel 051/061 engines, which I have but do not use) at way higher engine output than with the stock high-compression COX head, or with the Merlin insert plug,  PLUS most importantly, for their use of common - not the limited availability Nelson- turbo plugs (not just OS), which are sold in most hobby shops. So Kamtechnik head="eternal" availability of glow heads for my COX 049/050/051 engines.

More good info. Thanks Balogh!

Wow! New to me heads. So these are similar to Galbreath heads but don't need Nelson plugs with odd thread pitch?


https://kamtechnik.com/product/ktk-11/

crankbndr wrote:Wow! New to me heads. So these are similar to Galbreath heads but don't need Nelson plugs with odd thread pitch?


https://kamtechnik.com/product/ktk-11/

Yes, Doug, exactly this is the case...the Kamtechnik head has a thread size of any common glow plugs i.e. different than the unique Nelson thread,  but a tapered bottom to seal with the tapered tip of the turbo plug. Wide variety of these common i.e. non-Nelson turbo plugs are sold in most hobby shops - even in countries where IC engine use in models is almost extinct, like in Hungary -  from cold to medium to hot (the latter are used in RC cars I guess).

For clarity. These are not for standard 1/4"-32 plugs. These take "turbo" style taper seat plugs which are common in RC cars. Any hobby source should be able to supply them, and if the local shop does a lot of cars they will probably have them. Turbo plugs allow for better sealing and more control over the shape of tiny combustion chambers.

Sure Greg, that is what I also meant...BTW do you plan to extend your turbo head offering to COX 020 and 090 sizes too? The prototype 090 you sent me works fine, and I guess Brad has also successfully tested the 020.

Thanks, Andras

Yes. .020 heads will go into production in the next few days. .09 shortly after, a change was made to reduce the number of gaskets required. NV .074 heads are coming also. I'll be adding items to the site this week and they will go live when stock is available.

To most airplane people a "standard" plug is 1/4"-32. I know you know about turbo plugs, but many outside of RC cars, have never heard of them. Just like most outside of competition airplanes have never heard of Nelson plugs.

Greg

gkamysz wrote:Yes. .020 heads will go into production in the next few days. .09 shortly after, a change was made to reduce the number of gaskets required. NV .074 heads are coming also. I'll be adding items to the site this week and they will go live when stock is available.

To most airplane people a "standard" plug is 1/4"-32. I know you know about turbo plugs, but many outside of RC cars, have never heard of them. Just like most outside of competition airplanes have never heard of Nelson plugs.

Greg

WHOO! Been waiting for them 020’s, glad to hear the 09 and NV also! Just to put a bug in your ear.....how about a head for a Testors 049! ??

Marleysky wrote: Just to put a bug in your ear.....how about a head for  a Testors 049! ??

I have samples on my desk I need to test.....

Oooo cool! If you want to slip one or two in the package with my order for the upcoming 020 release, I’d be happy to bench test them!

gkamysz wrote:For clarity. These are not for standard 1/4"-32 plugs. These take "turbo" style taper seat plugs which are common in RC cars. Any hobby source should be able to supply them, and if the local shop does a lot of cars they will probably have them. Turbo plugs allow for better sealing and more control over the shape of tiny combustion chambers.

Guess I been out of the loop lately, sounds like a great product. Thanks!

We do still have a number of clamp rings (2-fin and 5-fin in silver and red) in stock in case anyone needs any. Just not listed as what is the point without the inserts?

Bernie,
Without wanting to sound rude, the point is to sell an item even if one of your competitors' parts may be required. Is there any chance Mecoa would enter into a wholesale agreement with you for their inserts?

I hope to find all my inserts and measure them tonight. The Mecoa inserts are clearly identified as having a wider body than the AP clamps can take. I'm hoping knowing the AP width and adding the difference from Mecoa would yield the required hole size. Maybe your clamps will already have the required hole size for Mecoa's inserts.

KAM,
Any chance you'll develop replacement heads for the Tee Dee/Medallion .15 engines? I have two and would like to future-proof those engines with your offerings.
TIA

944_Jim wrote:Any chance you'll develop replacement heads for the Tee Dee/Medallion .15 engines? I have two and would like to future-proof those engines with your offerings.
TIA

Prototypes are being tested now.

I just measured what I believe to be an NV at .332" diameter. An AP at .314" and a Merlin at .335" I suppose boring out the AP threaded clamp to .336" would allow any insert to work.

944_Jim wrote:Bernie,
Without wanting to sound rude, the point is to sell an item even if one of your competitors' parts may be required. Is there any chance Mecoa would enter into a wholesale agreement with you for their inserts?

I hope to find all my inserts and measure them tonight. The Mecoa inserts are clearly identified as having a wider body than the AP clamps can take. I'm hoping knowing the AP width and adding the difference from Mecoa would yield the required hole size. Maybe your clamps will already have the required hole size for Mecoa's inserts.

KAM,
Any chance you'll develop replacement heads for the Tee Dee/Medallion .15 engines? I have two and would like to future-proof those engines with your offerings.
TIA

We have absolutely no problem selling parts if they compliment someone else's wares but, when we found out that Merlin was no longer in business, we took down the listings as we figured that no one would buy them if the inserts were no longer available.

Mecoa: Bad experience years ago and they still owe us money for products that we pre-paid but they never supplied; so definitely a no-go there.

However, if anyone wants the clamp rings, here they are:

3-Fin adapter - silver https://coxengines.ca/product.php?productid=2260

5- Fin adapter - silver https://coxengines.ca/cox-.049-glow-plug-adapter-extra-cooling-silver-5-fin.html

5-Fin adapter - red https://coxengines.ca/cox-.049-glow-plug-adapter-extra-cooling-red.html

Bernie,
Ouch! I hate when a deal goes bad too. I didn't mean to peel a scab there. I understand not wanting to deal with particular vendors. There is a Porsche parts vendor outside of Atlanta I will never deal with ever since 1995...expensive part not as described despite phone calls to that vendor for his word that the part was, well, as described. I actually drove to the vendor for the return of the mail order part, yet he held the $$ for a month before issuing the refund.

Just out of curiosity, what size is the plug hole in the clamp? I didn't think to bring my son's Merlin-equipped Scientific FW-190 home from work today (wall art at work for now). Tomorrow I will, so I can make a quick spreadsheet between Merlin, Norvel and AP clamps/inserts...including the Norvel .049 and .061 clamps.

I'm thinking out loud here without having my Merlin clamp handy...but I wonder what it would take to make a plug adapter that your clamp would secure in a Cox engine.
I know "the other guy" (not EXEngines to avoid ambiguity) sells a plug adapter for the Norvel .074 that is held onto the block with the oem clamp. But this means a clamp, adapter and plug...three parts instead of only two.