RC India

General Topics => Beginners Zone => Topic started by: knvshrm on April 18, 2018, 03:58:53 PM



Title: Which material to use to make a firewall ?
Post by: knvshrm on April 18, 2018, 03:58:53 PM
Hi guys ... Was making the ft old fogey but was tuck here. What material should I use to make the firewall ?? Will 5mm depron do the job or would have to make it out of wood ? I am using the emax cf2822 motor with a 9 *5 prop.
Regards.


Title: Re: Which material to use to make a firewall ?
Post by: girishsarwal on April 18, 2018, 04:00:59 PM
Plywood! 5mm depron wont last a few minutes before breaking/bending/splitting to pieces.


Title: Re: Which material to use to make a firewall ?
Post by: girishsarwal on April 18, 2018, 04:08:34 PM
UPDATE: I checked your other post as well, take back my plywood suggestions. I guess you are good with the depron firewall given that motor.. you will need to specify your targeted AUW as well. I'd make it thicker than 5mm though


Title: Re: Which material to use to make a firewall ?
Post by: knvshrm on April 18, 2018, 04:12:25 PM
See the weight of the whole plane with electronics will be around 600 gms


Title: Re: Which material to use to make a firewall ?
Post by: knvshrm on April 18, 2018, 04:13:43 PM
I do have a peice of balsa but it is a bit small than the power pod front.


Title: Re: Which material to use to make a firewall ?
Post by: knvshrm on April 18, 2018, 04:20:05 PM
So finally is depron suitable ??


Title: Re: Which material to use to make a firewall ?
Post by: girishsarwal on April 18, 2018, 04:25:50 PM
Why do t you post some photos of your build, that will help us better with the decision making process


Title: Re: Which material to use to make a firewall ?
Post by: knvshrm on April 18, 2018, 04:34:00 PM
Always an error pops.


Title: Re: Which material to use to make a firewall ?
Post by: knvshrm on April 18, 2018, 04:34:38 PM
Can you plz PM. me your phone no. So I can send you the photos.


Title: Re: Which material to use to make a firewall ?
Post by: prabal276 on April 18, 2018, 04:58:48 PM
Please use plywood!
A depron firewall won't last!


Title: Re: Which material to use to make a firewall ?
Post by: K K Iyer on April 18, 2018, 05:07:33 PM
@knvshrm,
Mr Sarwal was actually right in his first reply!

That Emax CF2822 will easily pull well over 600gms.
The 4 mounting screws need something to hold on to, so that they don’t pull out.
Hence plywood.
The Flitetest plan of the power pod shows a 50x45x1.5mm ply firewall.
Often when I don’t feel like cutting ply into a nice round shape, I use 1/4” balsa.
If you have neither, use 1-2mm plastic from a jar lid or tiffin box.


Title: Re: Which material to use to make a firewall ?
Post by: K K Iyer on April 18, 2018, 05:12:31 PM
I do have a peice of balsa but it is a bit small than the power pod front.

Can be used if at least 3.5x3.5cm (or 3.5-4cm dia).
Just needs to be a bit larger than the mount (3cm dia)


Title: Re: Which material to use to make a firewall ?
Post by: knvshrm on April 18, 2018, 05:22:52 PM
The balsa peice broke...will be using the plastic lid.thanks sir .


Title: Re: Which material to use to make a firewall ?
Post by: prabal276 on April 18, 2018, 05:24:45 PM
Yes, that plastic jar lid is a great idea!


Title: Re: Which material to use to make a firewall ?
Post by: knvshrm on April 18, 2018, 05:29:26 PM
And sir how do I attach the power pod into the frame? FT people have just used some skewers and inserted the power pod there.how do I do it . I don't have those skewers.
Regards


Title: Re: Which material to use to make a firewall ?
Post by: knvshrm on April 18, 2018, 05:32:06 PM
https://youtu.be/w9VzlVO2adQ

See 12:28


Title: Re: Which material to use to make a firewall ?
Post by: prabal276 on April 18, 2018, 05:35:56 PM
Skewers are easily available on online websites cheaply.
I can't think of any other options.....
Maybe if you have some thin cheapo ball pens? You could empty then out and use them?
Or some thing aluminium tubing.
I suggest you get those skewers.


Title: Re: Which material to use to make a firewall ?
Post by: knvshrm on April 18, 2018, 05:37:08 PM
Ok


Title: Re: Which material to use to make a firewall ?
Post by: K K Iyer on April 18, 2018, 06:46:34 PM
Skewers, ballpen refills
Toothpicks. Pencils.
And my favourite, mentioned many times on this forum - PHOOL JHADU KI TEELI (handle end)


Title: Re: Which material to use to make a firewall ?
Post by: knvshrm on April 18, 2018, 07:05:52 PM
Thank you sir


Title: Re: Which material to use to make a firewall ?
Post by: knvshrm on April 18, 2018, 07:09:10 PM
But will phool jhadu ki will be sufficient to hold the power pod. Will it not break ?and can we leave the power pod on these skewers or the tilis will they be enough?


Title: Re: Which material to use to make a firewall ?
Post by: K K Iyer on April 18, 2018, 07:51:29 PM
The best proof is obtained by personal experimentation.
I typed a msg that was a lecture on shearing and bending loads etc, so I deleted it.
You are an engineer.
You have two adjacent surfaces to be prevented from sliding by pins.
One pin is a rod of 1.5mm
The other is a tube of 3mm dia, thin skin, weak core.
What you are asking is ‘which will break first?’

Need to consider the material the pins are anchored in. Depron.
Which will give way first? Skewer? Jhadoo? Depron?

The Jhadoo I mentioned was a Phool Jhadu, not a Seekh Wali Jhadu.

To give you a hint, why not anchor with Drawing pins?


Title: Re: Which material to use to make a firewall ?
Post by: taksh on April 19, 2018, 06:35:05 AM
Hi guys ... Was making the ft old fogey but was tuck here. What material should I use to make the firewall ?? Will 5mm depron do the job or would have to make it out of wood ? I am using the emax cf2822 motor with a 9 *5 prop.
Regards.
you are using 2200mah Lipo or any other?


Title: Re: Which material to use to make a firewall ?
Post by: knvshrm on April 19, 2018, 01:43:42 PM
1500 mAh 3s lipo bro.