Vacuum Bagging a Wing with a Food Saver

[dave_lilley]

http://www.ezonemag.com/articles/2002/jul/foodsaver/food_saver_f_t2.jpg (http://www.ezonemag.com/cgi-bin/alist/jump.pl?ID=728)

Vacuum Bagging a Wing with a Food Saver (http://www.ezonemag.com/cgi-bin/alist/jump.pl?ID=728)

By Jim Young

Jim Young shows us how a readily available off-the-shelf device that is normally used to vacuum pack food can also be used for bagging wings. new

[AirJer]

What a clever idea. I too have wanted to do some vacuum bagging, but have hesitated to commit to a serious pump system.

Looks like an entirely satisfactory technique!

[buckeyes1997]

i just bought this same system to do vacuum bagging and i think it will pull plenty of pressure to do a decent job.

i would like to know if anyone has tried using other bags than what comes with it. i am guessing the bags that come with it have ridges to allow air to be pulled out. if i try to use regular bagging sheet they dont have the grooves and so it doesnt draw a vacuum. ive tried putting paper towel around the lip as a bleeder cloth but it didnt work very well. i have since found a few models of vacs at stores that use a tube inside the bag's lip rather than special bags. im starting to wonder if that would have been better.

by the way i paid 50.00 for my kit at Kmart and it came with an extra set of bags.

matt
http://fms1.mattclement.com

[Kevin Murray]

Buckeyes - What brand is the set-up that you got at K Mart ?
It's the same Food Saver ?

[buckeyes1997]

yes mine is the foodsaver 550 model.

[Kevin Murray]

Time to let the CFO that it's time to start vacuume bagging food.
For health reasons ---- Of course.:p

[SteveS]

Along the same line, you can use a hand operated vacuum pump(the plastic kind used for auto repair) very well for small projects. I find that it's sometimes a pain to get the whole system out for one 3 x 36 x 1/16 sheet of FG/balsa/FG. Small bags with reduced volume can be made from polyproplene sheets with caulk, ziplock bags or 'found' materials. Vacuum will hold overnight if sealed properly. YMMV

Steve Smith
Atlanta

[GregG]

How high a vacuum can be pulled with this system? Can you do an all composite vacuum bagged blue core wing?

[AndyKunz]

The link at the top is dead. Anybody know where it is now?

Thanks.

Andy

[JFarlette]

I don't know where that specific article went but there are a number of them on the web. For example: http://www.info-central.org/construction_vacuumbagging.shtml

Jason

[rtideas]

Vacuum Bagging a Wing with a Food Saver (http://rcgroups.com/links/index.php?sid=682894021&t=article&having=73939&cat=202&id=3976)

[AndyKunz]

Thanks.

[Intrex]

I know of a cheaper way to vac bag, but its not as easy. you can buy a hand vac pump that mechanics use to test diaphrams and stuff. If you dont mind spending a little time its great, I suck out the bulk air first with my vacuum cleaner in reverse.The vac pumps have a built in vac guage too.

[BMatthews]

A few years back when I was playing with vac bagging I modified a cheap aquarium pump to suck rather than blow. It would draw about 2.5 lbs of vacumn. The more expensive ones would probably do a bit better but I'm not sure you need much more than this. At the full 2.5 psi of vacumn I was able to crush the surface of the individual beads of the white styro I was using for test panels. The wing looked like fish scales after curing from sucking the cloth and epoxy down so hard. I added a needle valve on a T as a bleeder to hold it to about 1 to 1.5 psi and the results were much better. The blue or pink 2 lb/cu-ft would take the whole 2.5 though. The bagging was great with that much vacumn. The best part was I didn't have to worry about the long run times since these pumps are made to work 24x7 for years at a time.

They are just small diaphragm types that use rubber cups as the variable volume chamer and use reeds for the valves. It's been a long time but it wasn't hard to drill a larger hole at the little pinhole air intake and add an intake tube to take the vacumn line.

[Tram]

Has anyone tried to vacuum some CF landing gear with this method? Do you think it would be strong enough with the food saver??

[Bigfootbis]

I've been using this system for over 15 years now. Your best bet is to go to a garden store and buy a roll of the yellowish plastic sheeting that they use for making forcing tunnels. This is quite thick - about 0.8mm - and so it does not ruck up. Cut to size and make your own bags, using the sealer. From the hole where the air is sucked out, run a piece of 4-5mm dia braided nylon cord right round the floam. This will allow the vacuum to work evenly all over the inside of the bag. The pump I use is a refrigerator pump with an adjuster to keep the vacuum down to around 200mm of Hg, more than enough for white foam. (And I had the CFC's rmoved correctly at a service place!). Use sanding sealer on the inside of balsa or obechi skins to avoid them soaking up resin and adding weight - only put the resin on the wood.

Have fun.