cmdi racing

[Richard Dahlheimer]

You now i just red some of the post in this thread and it's really sad to now that there is poeple like that out there first you had to wait for you boat thats fine then you cancelled it did you get ripped off for any money i don't think so but you decided to to go public with this matter and were did it get you do you feel better, I'm sure there are some poeple that don't.

  When your as busy as CMDi you have to wait sometimes  and you will only recieve quality in you product if you don't want to wait then you will get quanity from some offshore buisness.

  I have dealt with Andy and John and they are top notch guy's to deal with and that goes for the whole crew at Comp Marine.

  I'm sure if you guy's just wait with a little patiants Andy will let everybody now whats going on so give the man a little room and time i'm sure it will all be good

  P.S There's no need for rumors or thread's like this to be started <_<

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Guys, i just recieved my new SGX-ONE 20 boat from CMDI.The craftsmanship on this boat, is very very good. I purchased a 90% kit. John has all the parts fitted perfectly. This all takes lots of time. I also ordered propellers, rudder etc. My order was complete. Did i have to wait for my order? yes, i waited 3 months, but it sure was worth it. Great job guys, and gals at CMDI. Andy, any chance of a SGX 20 build up thread, next? Just my 2 1/2 cents worth. Newbie, Richard D.

 

[Don Ferrette]

You now i just red some of the post in this thread and it's really sad to now that there is poeple like that out there first you had to wait for you boat thats fine then you cancelled it did you get ripped off for any money i don't think so but you decided to to go public with this matter and were did it get you do you feel better, I'm sure there are some poeple that don't.

  When your as busy as CMDi you have to wait sometimes  and you will only recieve quality in you product if you don't want to wait then you will get quanity from some offshore buisness.

  I have dealt with Andy and John and they are top notch guy's to deal with and that goes for the whole crew at Comp Marine.

  I'm sure if you guy's just wait with a little patiants Andy will let everybody now whats going on so give the man a little room and time i'm sure it will all be good

  P.S There's no need for rumors or thread's like this to be started <_<

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Guys, i just recieved my new SGX-ONE 20 boat from CMDI.The craftsmanship on this boat, is very very good. I purchased a 90% kit. John has all the parts fitted perfectly. This all takes lots of time. I also ordered propellers, rudder etc. My order was complete. Did i have to wait for my order? yes, i waited 3 months, but it sure was worth it. Great job guys, and gals at CMDI. Andy, any chance of a SGX 20 build up thread, next? Just my 2 1/2 cents worth. Newbie, Richard D.

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Rich, you p/m me for the set up if you like.

 

[AndyBrown]

Don Wrote: "Rich, you p/m me for the set up if you like."

The set up for the SGX-ONE is different the the SGX Don. Just wanted to let you guys know so there is not confusion when trying to compare notes.

 

[Don Ferrette]

Don Wrote:  "Rich, you p/m me for the set up if you like."
The set up for the SGX-ONE is different the the SGX Don.  Just wanted to let you guys know so there is not confusion  when trying to compare notes. 

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Ooops, missed that in last sentence, he said SGX20.

 

[holgionline]

John,
Right on! Andy, John,and CMDracing are top shelf in the R/C boating world.

I am still learning stuff on their race prepped propellers,they are without a

doubt, one of the best in the propeller world also.

Thanks For Sharing,

Mark Sholund

Props-4-U

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i would'nt say the props are without a doubt.....of course they are not bad but they could be better if cmd racing hardens the props......especially the octuras bend under the pressure of the water.......i destroyed some of them......best regards, holgi !!!

 

[Don Ferrette]

i would'nt say the props are without a doubt.....of course they are not bad but they could be better if cmd racing hardens the props......especially the octuras bend under the pressure of the water.......i destroyed some of them......best regards, holgi !!!

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Take no offense Holgi, but I'm beginning to think you are one of those people that there just ain't no pleasing.... <_<

 

[AndyBrown]

John,
Right on! Andy, John,and CMDracing are top shelf in the R/C boating world.

I am still learning stuff on their race prepped propellers,they are without a

doubt, one of the best in the propeller world also.

Thanks For Sharing,

Mark Sholund

Props-4-U

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i would'nt say the props are without a doubt.....of course they are not bad but they could be better if cmd racing hardens the props......especially the octuras bend under the pressure of the water.......i destroyed some of them......best regards, holgi !!!

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We have tried to harden them. Then they break which is a dangerous situation. I have a pile of broken props to show for our efforts. If they are weak enough to bend then there is no proper amount of heat treating that will keep them from breaking/bending. Even if the broken blades were to never hit anyone, they would normally do damage to the hull and/or hardware everytime they break. We have no control over the alloy that Octura or ABC uses to cast their props.

 

[holgionline]

hi don,

you can't offend me........not in a forum........of course you can think what you like but would you be pleased about that :

why not talk about technical problems and find out how to eliminate them ?

@ andy,

sorry, but i don't agree with you......since i harden my props, they don't bend under the pressure of the water and they don't break.......and my props spin with 40000 rpm and more.......by the way......for everybody who's interested.......a hardened prop looks like that :

best regards from germany, holgi !!!

 

[AndyBrown]

Interesting 2250 there. That does not look like our work. If in fact it is and this is a problem with props you have gotten from us why have you not brought it to my attention before this?

The 2250 is a very high pitched prop and if made too thin will definatly have problems. Do you have a photo of a 2250 that is just as thin and that has been heat treated and run successfully?

You could have sent the same photo to me at [email protected]. You know that address; and I would have taken care of the problem.

Interesting thing is that I've never heard of you before you posted on this forum even though I now know that you ordered a boat from us.

Any complaints like this that are e-mailed to cmdi or cmdi3 are always brought to my attention.

We just finished an order of about fifty props to be sent to Germany and have sent many before this. Someone there must be having success with them.

We prepare a very large number of props every year and problems like this are very few and when there are I replace them always, at no charge. If it countinues to be a problem, I suggest a different prop for the application and supply it at no charge.

That is a nice looking V947/3 you have there. They normally don't have bending issues if the blade thickness is not altered too much. So your nice photo doesn't prove much.

In the end I'm not oppssed to the customer heat treating their own props. If it is done just right it will reduce the chance to bend, but if it is cooled just a little too quickly it could surely break.

Hope you have a nice boating season.

 

[holgionline]

hi andy,

i bought this prop from alex soell and he told me, that it is a cmdracing prop but maybe he made a mistake or i misunderstood him.......normally he is a real nice guy.

i don't have the same prop heat treated and meanwhile the boat is destroyed......so i can't test under the same conditions.

to come to the v9 series : i'm sorry but i have to tell you that i destroyed some of them......and they were from cmdracing for shure........but it's not a problem anymore......i harden them and they work perfectly.

and don't worry......i'm not angry about you or the props......your stuff is ok.

the other thing is : isn't it possible for you as a big customer from octura to have an influence on them to make the props with an higher beryllium percentage or to produce props in cobaltchrome steel or something that is harder than beryllium copper ?

best regards, holgi !!!

 

[shoboat]

Boaters,

The real problem with some of the current propellers on the market, is

the material that they are casted from. The ABC propellers have a much

stronger alloy then just about any propeller manufacture out their.

And the other issue with bending or breaking them, is

really how thin they are prepared for the best performance possible.

Mark Sholund

Props-4-U

 

[AndyBrown]

Holgi,

You are running fast electric. There is certainly a requirement for strong props on those boats because of the instant motor torque and extra weight of those boats.

Glad you know the correct heat treat method. Maybe you will share it with everyone.

Sorry , but I don't have any influence on Octura.

Mark, The ABC props are no better than Octura. We have broken and bent many of the ABC. If fact many of the new ABC's break so much we don't stock them.

Prather Stainless props are by far the strongest out there with Simon Higgens (Prop Shop UK) being second. I would say ABC and Octura are eaqually at the bottom.

Unless something has changed that I don't know about, Octura is not cast in Germany. With the cost of the Euro and shipping, that would not be a wise business move.

Also Mark, You have no clue how many props we do , so I would suggest you not post information you know nothing about.

Most all of your "observations" in your post are not correct.

 

[holgionline]

hi andy,

i would not say abc and octura are equally on the bottom......abc uses another alloy than octura.......the abc props are much better to harden than the octuras.....i suppose, jim schaefer uses an alloy with higher beryllium percentage or maybe an alloy with cobalt.

you asked me for sharing my heat treat methods with everyone.......no problem.....i don't have secrets :

the trick at the abc props is to harden the surface and not the complete material......it's really easy.......all you need is a good stove in your kitchen that makes a temperature of about 280° - 290° C.........get the prop in the stove and then switch it on........when the stove has reached the maximum temperature of about 290° C wait one hour and then switch it off.......don't take out the prop.......let prop and stove cool down slowly........now you have to wait 24 hours before you can use the prop.........shaping, balancing or whatever has to be done before this heat treating method.......it's not possible to prepare a hardened abc prop with normal tools.......the surface is extremely hard now.

ok, so far so good........hardening octuras is a little bit more difficult......first of all you need a stove that makes about 350° - 360° C.......the best would be a dental stove like this :

http://cgi.ebay.de/ws/eBayISAPI.dll?ViewIt...ssPageName=WDVW

or that :

http://cgi.ebay.de/ws/eBayISAPI.dll?ViewIt...ssPageName=WDVW

i tried several methods to harden the octura props.......different temperatures, cooling down slowly, cooling down quick.......and so on.......but i had the best results with the following method :

adjust the dental stove to 350° - 360° C.........get the completely prepared and balanced prop into the stove and switch it on........let it in the stove for about 4 hours........open the stove, take out the prop and dive it quick into icewater (with the drive dog side first)........wait 24 hours before using the prop.

in the last months i spent a lot of time on finding out the best method to harden beryllium copper and my tests are not finished yet......the difficult part is, that octura props always seem to have a little bit different alloys......if i find out something new i will let you know.

ok, another thing :

i ask myself why manufacturers like abc and octura still use dangerous alloys like beryllium copper.......polishing the props (dry) and breathing the dust can cause serious lung damages........and i know, that octura is able to produce in stainless steel as this photo shows :

so whats's the problem ?.......higher costs ?.......i would pay more for it.

best regards from our side of the atlantic, holgi !!!

 

[AndyBrown]

Thanks for the info Holgi. You have certainly done your home work.

I have asked Octura many times why he does not make good stainless props.

He never gives a logical reason why not. Unless "too hard to work on for the modeler" is a logical reason.

 

[holgionline]

hi andy,

hahaha.......really a nice answer from octura....... ...... what about making the suggestion to produce props with a higher beryllium percentage and maybe a little bit cobalt ?........i think, that could reach the fe racers ok.

ok, a few words to everybody who's planning to harden his props :

NEVER do cupping on a hardened prop !!!.......the material can tear structural and invisible for human eyes........imagine what happens if a blade breaks away from the prop and flies around like an uncontrollable knife........people like friends or children can get injured seriosly !!!

best regards, holgi !!!

 

[TonyKilbarger]

ABC definitely adds cobalt and I believe a small amount of Titanium to their alloy. I know from talking to Jim at ABC, the biggest problem with stainless is it does not fill the mold fully unless you dramatically increase the blade thickness. I believe the blade thickness on a prather prop which does come in stainless is much higher than many of the ABC props. The H7 and H10 props I believe taper to less than 10 thousandths at the tip. Some prather props measure up to 6 times that thickness.

 

[holgionline]

hi tony,

that declares why the abc props get much harder than the octuras after heat treating !

blade thickness should not be a too big problem.......i know somebody who is really good in making the blades thinner........ .........sorry andy.......just a joke !

best regards, holgi !!!

 

[Dale0]

So any new news on who is going to be making the new Macs?

 

[Norm Doerr]

I want a Mac 90!!!

 

[holgionline]

hi folks,

for everybody who likes to learn more about beryllium copper ( safety facts, welding, machining, etc.).......this is really a good site :

http://www.brushwellman.com/alloy/products...ing_alloys.asp#

if someone knows details or can find out details about the alloy that is used by octura, please let me know.

best regards from germany, holgi !!!