Question about upgrading to "bigger" EDF

[Crick3t]

I am wondering if anyone has played around with swapping out EDF's in their jet's for a bigger size? For example if you have an F35 70mm putting an 80mm edf unit in it. Or taking any 80mm jet an putting a 90mm unit in it.

Are there efficiency gains / power gains / or is all of that lost with weight and bias changes ?

If anyone has experimented or just up and done this I'd love to hear about the results.
Thanks!

[TiredIronGRB]

I am wondering if anyone has played around with swapping out EDF's in their jet's for a bigger size? For example if you have an F35 70mm putting an 80mm edf unit in it. Or taking any 80mm jet an putting a 90mm unit in it.

Are there efficiency gains / power gains / or is all of that lost with weight and bias changes ?

If anyone has experimented or just up and done this I'd love to hear about the results.
Thanks!

I put an 80mm in my F-35 and it was a turd

[Crick3t]

Why though? Just saying it was a turd doesn't really do any good. Yes it implies it was not a good upgrade, but why? Weight issue? Battery issue? Intake or Outlet size issue? What did you do to figure out it was a turd? Did you just fly it and go by what you heard or saw / felt?

I'm trying to get some good input if anyone has experience with this.

Thanks.

[TiredIronGRB]

Not enough air intake, it would barely get off the ground...I did a write up on it here on HS...

[Crick3t]

Not enough air intake, it would barely get off the ground...I did a write up on here on HS.

Ok that makes sense. Can you link it for me please? I'd love to read through it, but i'm having trouble finding it.

Is this the only air frame (f35) you tried it on? Do you think other platforms might be better suited to doing something like this? I am pretty sure the freewing f-18 comes setup to run either 80 or 90mm fan.


I've been trying to find info on doing something like this and have had no luck until your replies TiredIronGRB
Your knowledge is greatly appreciated!!!

[mshagg]

Chalk another failed experiment squeezing an 80mm into an F35 here.

This stuff is reasonably complex, there's a lot of trade offs and considerations in the design of the intake and exhaust ducting. I think alpha has made some pretty detailed posts on the topic.

[Beeg]

Ok that makes sense. Can you link it for me please? I'd love to read through it, but i'm having trouble finding it.

Is this the only air frame (f35) you tried it on? Do you think other platforms might be better suited to doing something like this? I am pretty sure the freewing f-18 comes setup to run either 80 or 90mm fan.


I've been trying to find info on doing something like this and have had no luck until your replies TiredIronGRB
Your knowledge is greatly appreciated!!!

Are you looking for thrust, flight time or just wanting to tinker? You can always change the motor and/or fan without changing EDF diameter.

[Evan D]

I put a 90mm into a 80mm F-86 and it was perfect. It was the lower power old FW 6b set up that drew less power than the 80mm but was much more efficient. More power and longer flight time.

I put a 80m in a 70mm F-16 and it was a fail. Insufficient intake area.

[Crick3t]

Are you looking for thrust, flight time or just wanting to tinker? You can always change the motor and/or fan without changing EDF diameter.

Just looking to tinker and if i can get more power and maybe a little more efficiency then win win.

[xviper]

Rather than putting in a "bigger" EDF into an existing plane, you might want to replace it with the same size EDF but a higher performing one. You need to also look at a bigger ESC to match.

[Crick3t]

Rather than putting in a "bigger" EDF into an existing plane, you might want to replace it with the same size EDF but a higher performing one. You need to also look at a bigger ESC to match.

Rather than coming up with something off topic why not answer the question at hand. Also I am aware of that and well informed on what is needed, but that isn't the question or topic of this. I am specifically asking about a bigger EDF.

[xviper]

Rather than coming up with something off topic why not answer the question at hand. Also I am aware of that and well informed on what is needed, but that isn't the question or topic of this. I am specifically asking about a bigger EDF.

That is a very UNpleasant response and uncalled for. I shall no longer be of any assistance to you from this point on. You shall be put on my IGNORE list. With your attitude, you are NOT deserving of help from anyone. You have a really nice life and good luck with all your future questions.

[Hardway]

[Crick3t]

That is a very UNpleasant response and uncalled for. I shall no longer be of any assistance to you from this point on. You shall be put on my IGNORE list. With your attitude, you are NOT deserving of help from anyone. You have a really nice life and good luck with all your future questions.

I'm sorry you feel that way. I was simply pointing out that your response to the thread was off topic and not much help for this reason.

[Evan D]

And my response was on target and not responded to...

[Crick3t]

And my response was on target and not responded to...

Yes your response was on target. It was read and taken in. I guess i didn't realize that a response is required for every single post.

[Evan D]

No, but it’s nice to know if it was what you were looking for.

[Crick3t]

It was.

Thank you!

[tab28682]

I think the responses suggesting a better fan unit of the same size are a very valid point to make, even if the comment is off of the exact direction of this thread.

I think you will find that nearly all cases, simply installing a larger diameter and more powerful EDF will not work well if at all, due to the intake and exit ducting being optimized for the fan it was designed for. The experiences of the two modelers that did attempt to upgrade the F-35 to 80mm units confirm this. Once in a while, there will be an exception that proves the rule, like the mentioned F-86 conversion. In order to see if an aircraft might be an exception, be prepared to study and calculate the needs of the desired EDF setup and analyze the intake and exhaust ducting to see if it might work, or what modification might be needed. Let's face it, you have to feed that fan.

Most modern EDF ARFs have pretty decent ducting, optimized for what is going in it. Putting in a larger EDF that wants a larger volume of air is often going to be a waste of time.

After flying my FW F-35, I was particularly impressed with the performance and speed of the model, given the 70mm fan and the weight of the model. They apparently did a great job on the ducting.

Worth mentioning that it is better to ignore a slightly off topic response that goes in a different direction that you desired, or to politely mention that you understand that approach and are not interested in it, than to take people to task over not following your exact request.

[Evan D]

This is a good post. I will say that while I converted my 80mm F-86 to 90mm I used the older low power 6b fan and it worked probably because of the lower power and fan swept area. I sold that plane and the new owner blew up the fan. Since he had a newer 12b 90mm he put that in and it had about half the power it should. He asked me what to do and I had a spare fan that I gave him and he was back flying.

The 80mm I put in the 70mm F-16 was a 12b. I think if I had put in a lower power 6b 80mm it may have worked.

I think the responses suggesting a better fan unit of the same size are a very valid point to make, even if the comment is off of the exact direction of this thread.

I think you will find that nearly all cases, simply installing a larger diameter and more powerful EDF will not work well if at all, due to the intake and exit ducting being optimized for the fan it was designed for. The experiences of the two modelers that did attempt to upgrade the F-35 to 80mm units confirm this. Once in a while, there will be an exception that proves the rule, like the mentioned F-86 conversion. In order to see if an aircraft might be an exception, be prepared to study and calculate the needs of the desired EDF setup and analyze the intake and exhaust ducting to see if it might work, or what modification might be needed. Let's face it, you have to feed that fan.

Most modern EDF ARFs have pretty decent ducting, optimized for what is going in it. Putting in a larger EDF that wants a larger volume of air is often going to be a waste of time.

After flying my FW F-35, I was particularly impressed with the performance and speed of the model, given the 70mm fan and the weight of the model. They apparently did a great job on the ducting.

Worth mentioning that it is better to ignore a slightly off topic response that goes in a different direction that you desired, or to politely mention that you understand that approach and are not interested in it, than to take people to task over not following your exact request.