Shop our Airplanes Products Drone Products Sales
Thread Tools
This thread is privately moderated by ExperimentalAir, who may elect to delete unwanted replies.
Apr 16, 2018, 02:16 PM
Registered User

Another source for better quality foam board


FYI, if you live in the west coast near LA or SF, Tokyo Central has in stock multicolored better quality foam board. The paper appears to be higher quality as well as the adhesive to the foam. Looks about the same size as the DTFB. Itís alittle more expensive than DTFB at $1.50 per sheet.
Sign up now
to remove ads between posts
Apr 20, 2018, 06:55 PM
Registered User
Quote:
Originally Posted by rhokita
FYI, if you live in the west coast near LA or SF, Tokyo Central has in stock multicolored better quality foam board. The paper appears to be higher quality as well as the adhesive to the foam. Looks about the same size as the DTFB. Itís alittle more expensive than DTFB at $1.50 per sheet.
Wow that's cheap! Locally I paid £10 for 5 sheets of foamboard that is quite a bit heavier that dtfb. And only availible in white or black. That's why I moved to hk foam and coloured packing g tspe
Apr 21, 2018, 01:59 AM
Registered User
davereap's Avatar
HK foam is fine... also check out the Diall xps board from B&Q...its a 5mm light weight green material..24" wide and works well ,
Use identical building methods. The 22" below is made from the Diall board
https://www.diy.com/departments/dial...1570772_BQ.prd


more on my mini blitz... speed delta... previous post 5881
on 3s its great...
.
the videos are of the 22" version with central fin and rudder...using a 3s 450
.
22inch mini blitz 1 18 april 2018 (6 min 50 sec)

.
22inch mini blitz 2 18 april 2018 (4 min 49 sec)


Below is the closest drawing to the original 20" blitz model... for its build dimensions .. the original is slightly smaller and has twin fins with no rudder
Here is a link to my build thread on both sizes.... for all the info in one place..
https://www.rcgroups.com/forums/show...tz-speed-delta

the 20" version should be easy to cut from the cheap foam board or from the hobbyking 5mm foam
dont forget the laminating film for a tough model.
Last edited by davereap; Apr 30, 2018 at 12:19 AM.
Apr 24, 2018, 12:58 AM
Registered User
davereap's Avatar
And on the Mini Blitz, I have just built the basic 20" version in 6mm depron foam... It is a KFm2 wing
https://www.rcgroups.com/forums/show...tz-speed-delta
its a cutie that should go fast..
A foamboard build will work nicely.. as the board weighs much the same as the 6mm depron I used, its an easy build from 1 sheet of foam..

Yes it does go fast.... I am still making adjustments, two props are going to be trialed... a 5x4.5 triblade and a 6x3.. the 6x4 used in the video seemed to draw a lot from the lipo.. although it went well enough..
I have cut the fins down slightly, their height is now 87.5mm.. this is trying to get a better flight angle whilst in ta banked turn, on flight1 the nose was dropping as the model was banked over.
.
the flight was mostly at 25% throttle...
.
20inch mini blitz 1 24 april 2018 on 3s 6x4 (4 min 51 sec)


Its now been given a good bashing and thrashing... using a Dalprop5x4.5 triblade it goes very nicely.. I have crashed it a few times hard, doing cart wheels across my field..lol..
and it is very tough, no damages at all.. the dalprop is unbreakable so its all a good match.. speed is not hypersonic, but thats down to my setup..
It is however fast enough and very smooth once its been trimmed properly..
The COG is 10mm in front of the KF step at the centre/root of the wing.. control movements are best kept small , well below 1/2" and very low rates were needed..
more videos are on my thread.. check out the crashes...
Last edited by davereap; May 04, 2018 at 10:22 AM.
Apr 29, 2018, 10:42 PM
Epilepsy Awareness
Flying High Mike's Avatar
Great thread. I'll be following Guys and Girls.

Mike.
May 22, 2018, 11:48 AM
Outlaw
gatorb8's Avatar
thanks for the construction tips!

https://www.rcgroups.com/forums/show...ostcount=27958
Latest blog entry: FPV 250 Cruiser Quad
Jun 13, 2018, 02:25 PM
Registered User
SilbernerSurfer's Avatar
Name: Butterfly_floats.1.jpg
Views: 20
Size: 38.4 KB
Description:

Would it be possible to build something like the Maxford Butterfly out of HK foam sheets and transparent covering foil?

As light as possible with a slow fly airfoil? Wingspan from aound 1000mm to 15000mm?

(No need for the floats, I have just liked the color so much!)
Last edited by SilbernerSurfer; Jun 13, 2018 at 04:03 PM.
Jun 13, 2018, 04:04 PM
Registered User
SilbernerSurfer's Avatar
https://www.banggood.com/de/2500mW-A...r_warehouse=CN

Is a cutter, or engraver like this usually used to cut the parts out of foamboard?
Jun 13, 2018, 05:38 PM
Registered User
tspeer's Avatar
Quote:
Originally Posted by SilbernerSurfer
https://www.banggood.com/de/2500mW-A...r_warehouse=CN

Is a cutter, or engraver like this usually used to cut the parts out of foamboard?
Cutting polystyrene foam is the #1 cause of laser cutter fires. It would be better to use a CNC machine that mills the parts rather than cutting them with a laser.

That said, I've found a good way to use a laser cutter is to cut out templates from utility plywood (0.1" thick), and then use the templates for cutting the foam using a hotwire set up like a scroll saw.
Jun 14, 2018, 06:30 AM
Registered User
SilbernerSurfer's Avatar
Quote:
Originally Posted by tspeer
Cutting polystyrene foam is the #1 cause of laser cutter fires. It would be better to use a CNC machine that mills the parts rather than cutting them with a laser.

That said, I've found a good way to use a laser cutter is to cut out templates from utility plywood (0.1" thick), and then use the templates for cutting the foam using a hotwire set up like a scroll saw.
Thanks a lot, tspeer!

Thanks for the hint with the ply!

Is a cnc machine available for at home, similar to the laser cutter?
Jun 14, 2018, 06:44 AM
Jack
jackerbes's Avatar
The main reason we use foam to build airplanes is because it is a less expensive and readily available material. And we use straight edges and parts templates and cut parts from the 4mm to 6mm or so thick foam sheets with various razor knives.

The building techniques for scratchbuilt foam aircraft is quite different but it can work well and produce airplanes like you describe.

And there are covering techniques for foam that will produce nice looking and colorful aircraft too. They are not exactly the same as that Maxford Butterfly but they are similar and can fly in a similar manner.

If you look at that plane and look at planes like Russ40 Trainer Type Plane you can see how those are built using sheet foam.

And for wings the things like the KFm3 Polyhedral Tip wing will give you a similar wing design.

Because of the projected heat in the laser cutting process, it may be that it will work but is not the best way to cut foam. And it is certainly not an inexpensive way to do it.

Jack
Jun 14, 2018, 08:10 AM
Registered User
The "Mostly Printed CNC" is mentioned elsewhere in RCGroups. It's an affordable hobbyist CNC that can do all sorts of things including cutting foamboard.
I don't have one yet but it's on my list.
Jun 15, 2018, 05:42 AM
Jack
jackerbes's Avatar
I wrote:

Quote:
If you look at that plane and look at planes like Russ40 Trainer Type Plane you can see how those are built using sheet foam.
I left some of the words I intended to use out, I meant to say that if you look at the Blu Baby 33 builds and planes like the Russ 40 Trainer Type plane for the wing build you can see the sheet foam builds. The Russ40 Trainer Type plane uses a stick type fuselage (CF arrow shaft) and a foam block rather than the built up BB 33 type fuselage but either way is a practical foam building approach.

Jack
Jun 15, 2018, 08:02 AM
Registered User
As said earlier the MPCNC is a good option, I use mine with a needle cutter. Other people use routers on theirs to cut foam and plywood. Rascal CNC is also an option.
Jun 15, 2018, 06:58 PM
Registered User
Utting foam with laser is tricky since the foam reflects most laser light. Yiu need an infrared laser which will be absorbed hy the foam rather than reflected.

People have tried with various lasers and got various less than ideal results.


Quick Reply
Message:

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion EDF/Motor for University Design Project uwpropulsionguy Electric Ducted Fan Jet Talk 2 Oct 14, 2018 04:51 AM
Build Log SEW-SLO 30" Foamboard Wing Atx_Heli Foamies (Scratchbuilt) 76 Apr 20, 2018 09:24 AM
Build Log SEW-SLO 30" Foamboard Wing Atx_Heli Flying Wings 0 May 19, 2011 09:47 PM
Question So I have a sheet of $Tree foamboard... what to build? Bomb Dropper Foamies (Scratchbuilt) 15 Mar 23, 2011 02:49 PM