52 inch span B25 free plans - Page 41 - RC Groups
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Aug 21, 2010, 02:58 PM
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drifter_uk's Avatar

Power supply

Hi sparks and guys been looking for a psu for the hot wire and think ive found something


just wondering if this would work what do you guys think. Thanks in advance and sorry if posting in the wrong section

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Aug 22, 2010, 07:11 PM
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byrocat's Avatar
I use a doorbell transformer and dimmer switch. http://www.radioshack.com/product/in...ductId=2102700

Looks like it's a fair match for cutting wire and the variable voltage will work.

However, be careful using it, especially if the voltage output is AC.
Nov 03, 2010, 05:23 PM
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Vacuum SetForming

I am building a B-25 at present from foam and have received a lot of help from your book.

What material and thicknesses do you use for your parts on the B-25 ? Would you give me guidance on best sites to look for help on vauum forming.
Nov 03, 2010, 07:03 PM
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Highfly!'s Avatar
Why would you want to do your own vacuum forming when you can get all the formed plastics directly at www.parkflyerplastics.com?

Forming your own plastic is not that difficult or expensive to setup. It will require some experimenting but if you have a shop vac you can already do a lot. A good book about this subject is vacuum forming by Douglas E. Walsh
Nov 04, 2010, 10:10 AM
Registered User

Vacuum Forming

I have already purchased very fine parts from Keith Sparks for his Bronco. I would like to be able to do my own for any model I build. Also postage rates to the UK can be rather excessive.

I have made a canopy but while OK it was quite difficult to form due to the styrene being too thick for my old vac to handle.

Thanks for the suggestion on Walsh.
Sep 22, 2011, 05:06 PM
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Hello everyone, at first sorry for my English.I could ask what material is used to build the model? Extruded polystyrene or normal polystyren? What model ultimately weigh? What there are engines and bateri? Thank you
Sep 22, 2011, 05:28 PM
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sparks's Avatar
Extruded styrene . . .blue or pink foam

Eflight 480 outrunner

all up weight 57 ounces
three cell 2200 batttery
25 amp ESC
Sep 23, 2011, 04:11 AM
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wow, its great. I thought it would weigh more. Balsa on it probably is not?
You really helped me I wanted to build from normal polystyrene. This will be better
Sep 23, 2011, 01:44 PM
It's a Great Day to Fly
LenBFP's Avatar
Online source for applicatiors:

Sep 23, 2011, 10:41 PM
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sparks's Avatar
Dont forget that WOW planes sell a kit of pre cut foam parts and the plastic for this design.
Jun 13, 2013, 07:18 AM
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Hi, anyone have an address in the US or Europe from where I could purchase Keith`s book on foam cutting
Jun 13, 2013, 07:37 AM
EB-66C Team Member
J Morgan's Avatar
Originally Posted by bonzo1
Hi, anyone have an address in the US or Europe from where I could purchase Keith`s book on foam cutting

Jun 19, 2013, 05:21 PM
Registered User

Sparks book

Originally Posted by J Morgan
Thanks J,
The book is now winging its way to Spain, should be with me this week
50mm foam sheets in workshop awaiting more info on B25
Jun 22, 2013, 06:05 PM
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sparks's Avatar
I'm here for you just ask if you get stuck.
Jul 12, 2013, 12:06 PM
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Originally Posted by sparks
I'm here for you just ask if you get stuck.
thanks for your offer.
been building with foam for about 5 years now, depron and 50mm extruded, the B25 caught my eye as crossover from built up fuz to foam.
Some 40 years ago I built a UC B25 3 line (motor control) always liked the B25.

Are the canopy's still available, as I am in Spain I checked the German shop but they were not listed.
My plans are to build it as a removable wing, with flaps, (solid core wing), balsa skin (wing) with servo´s in the wing and tail. Fixed U/C. A long term project for me.


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