Gyr

I have a Boss 602 ducted fan made by Turbofan, I guess around the 1970 /80s. Does anyone know or have any idea what happened to the company, It was based in Cleveland UK. Any info what so ever would be great!

Ron Stahl

My Feedback: (12)

We had two of them in my club and they were sold in the US by Kress Jets. We had OPS .67 's in both units and they blew the blades off destroying the units. Crap as far as we were concerned, got dynamax's to replace them and did not look back never had an issue.

jonastecknare

These fans come from sweden by a firm called Lyco if i remember correctly. It first came out something like 78-79 an vent through several updates. I have several of these and actually flew one this summer in my owndesigned "monster" I used a OS77 and i dont think you should use a bigger engine than that. Maybe KB81 or Rossi 81. If you put it together properly it acyually works fine.
However the rotorblades are very thin and sensitive t FOD, so if you do not have a lot of spareblades ( or can make your own) I would use another fan! I have made a mould, so i can make blades for myself but this is very workintense so i dont fancy doing it for anyone else! Sorry! Picture is my first "monster" Made of white foam/ plywod an covered in paper. Boss fan and OS77. Owndesign electrical landinggear. flew fine until battery desided it was enough.
Jonas

Gyr

Thanks guys really help full, with your comments I may change my plans as these don't sound very robust units.

Gyr

Hi JONASTECKNARE, like what you have done especially the mould for the fan blade. could I ask how you did this because I am very keen to do the same.
would you consider posting some pics of the mould. I would really appreciate some help with this, as I have trawled the net without to much success.
Martin

Mike Haddox

My Feedback: (5)

Put it in the trash can and back slowly out of the room.

jonastecknare

Why? He might learn something useful! i know i did!
The blade in the pics is not from Boss, its from an own designed fanunit for a large Saab Viggen. Will have three fans.
Alright , you need a disposable blade because you will probably ruin it!
I put some thin adhesive tape on the bakside of the blade and cut it to exact size and rub it so it sticks well.
Then i made a "skirt" from balsa, then i covered i with solarfilm.
Next i waxed the surface but not the bottom.
Then i made a box from cardboard, put the "plug in the bottom with some glue.
The i poured resin over the plug in the box carefully so there is no bubbles.
When this has hardened properly i open the mould, clean it and wax it several times.
I clean of the original blade and put it in the mould and wax again, several times.
Next i build up "walls" around the mould, i glue this so resin wont leak.
Then i pour resin in again and let it harden!

I have tried to use epoxi and gelcoat but what worked best was "Ureol"

jonastecknare

OK! making the blades.
Brake apart the mouldhalves, this can be very hard. Try not to hurt yourself or the moulds.
Clean up the moulds, there can be no "ledges" dont know the word!
Next i take a dremel and make resin overflow canals, ithink you can see them in the picture.
The green/yellow is the Boss moulds.
Then i cut fiberglass an carbonfibrecloth to size. you have to experiment how many and how thick material you can use.
I think i used 2 layers of 80g/m2, then four layers of carbon, then 2 layers of 80g glass again.
The two middle layers of carbon was undersize, chordwise. On a bit more than the other!
Its very important to make the blades the same, mark blades with the wrong amount of cloth so you won mix them!
Then i brush the inside of the moulds with "vaseline" and lightly polish.
Right time to start!
I use a small brush to lay the glass and carbon, i use a bit more resin (24 hour epoxi) than needed.
Then i slowly press the topp mould down and try to avoid making airbubbles.
The epoxi should flow from the canals so its abit messy.
Put on clamps and wait until the next day.
Brake apart and try to get the Part out of the mould.
Its difficoult but try not to damage the moulds.
You wil need to trim and balance quite alot. but the blades will be stronger than the original!
Sorry about the pictures quality, i just had a crappy camera when i did this!
It might be better to make the moulds from silicon but i have not tried this!
Other pics is my owndesigned fanunit and my Mig29 which will have two Boss fans!
Good luck! The pain is worth it!
Jonas

jonastecknare

OK! making the blades.
Brake apart the mouldhalves, this can be very hard. Try not to hurt yourself or the moulds.
Clean up the moulds, there can be no "ledges" dont know the word!
Next i take a dremel and make resin overflow canals, ithink you can see them in the picture.
The green/yellow is the Boss moulds.
Then i cut fiberglass an carbonfibrecloth to size. you have to experiment how many and how thick material you can use.
I think i used 2 layers of 80g/m2, then four layers of carbon, then 2 layers of 80g glass again.
The two middle layers of carbon was undersize, chordwise. On a bit more than the other!
Its very important to make the blades the same, mark blades with the wrong amount of cloth so you won mix them!
Then i brush the inside of the moulds with "vaseline" and lightly polish.
Right time to start!
I use a small brush to lay the glass and carbon, i use a bit more resin (24 hour epoxi) than needed.
Then i slowly press the topp mould down and try to avoid making airbubbles.
The epoxi should flow from the canals so its abit messy.
Put on clamps and wait until the next day.
Brake apart and try to get the Part out of the mould.
Its difficoult but try not to damage the moulds.
You wil need to trim and balance quite alot. but the blades will be stronger than the original!
Sorry about the pictures quality, i just had a crappy camera when i did this!
It might be better to make the moulds from silicon but i have not tried this!
Other pics is my owndesigned fanunit and my Mig29 which will have two Boss fans!
Good luck! The pain is worth it!
Jonas

Gyr

First, Jonas my hero. As strait forward as it seems your description has been so invaluable it filled the in gaps rattling around in my head.
As for your MIG WOW! that's what I call a scratch build I would like to see the finished plane, you will need to post a video, its people like you that keeps the zing in this great hobby.
Never mind the $10,000 rtf give me a block of foam any day.

Did you measure the thrust from your home made fan.

PS. Mike had to smile at your post, but you need to take a deep breath turnaround GO back into the room and take a challenge! lol.

Thanks again to every one, well Jonas actually.

Martin

jonastecknare

Hi Gyr! you are quite welcome! Scratchbuilding is all what its about for me. I have a certain idea an want to see it in real life.
As for my homemade fan, i havent run it yet, as im still working on the centerbody and stators. i have based it on the Byrodrive but changed it to a pulling configuration. pics of centerbody (built upon a crashed dynamax centerbody)
Jonas

You might wanna check out my building thread of my Viggen! Building is abit slow now but i will get there!
http://www.rcuniverse.com/forum/m_82...tm.htm#8211538