splinterz25

COOL John not very many people on this site RCU talking about building unless there ARF BASHING?

Okay I'm not going to get much done today were going to an outdoor concert for Fathers Day.
Happy Fathers day to everybody Enjoy your self !

I did how ever scratch out a quick drawing of the Vac-U-Box; the part over the heating element will be HINGED 1"x 1" ALUM - L- Bracket / stock w/ holes drilled every 1" or 2" for adjustment for different size projects.

They will sandwich a piece of 1" ALUM flat stock w/ a 1/4" 20 counter sunk headed bolt w/ a wing nut in a few places depending on how large the pieces of plastic is.

I don't show it in the drawing but the element side will be a all metal or lined w/ metal box; I'll make this after this first part.

THERE'S TWO PHOTOS so I hope you can see and understand where I'm going w/ this; Any intelligent thought or ideas, in addition to this drawing will be appreciated.

Bruce

splinterz25

I'll most likely post this on the builders work shop thread also after I have it fully built and up and running so I can show a video; I still need to order my plastic it comes from the west coast, I'll be ordering a few 4'x8' x 0.030 sheets soon.

Well I had to go get some more supplies this morning I'll show photos of what I'm using for those of you who would like to build one this way.

There's MANY ways to build these this is what I've come up with; I'm trying to make one set up to form using maybe three sizes of plastic sheet the largest being 18"x 22" and down this will help save plastic when doing small parts.

I've made my box using 1/2" ply this is my choice I don't like MDF it's heavy and harder to work with.

It's glued and nailed w/ a brad gun to hold parts until the glue dries.

I'll still be building the heat box next the heating element is on it's way from Seattle I'm using Galvanized sheet steal in side; but if you trying to cut coast heavy duty ALUM foil would probably work just fine, I want something that's going to last years.

I'm going to just post photos and let you guys & gals ask any questions you may have; I try to let the photos tell it all but you still may have questions.
IF YOU WANT TO SEE CAPTIONS W/ THE PHOTOS LOOK HERE
http://www.rcgroups.com/forums/showt...846463&page=37


Check it,

Bruce

splinterz25

Okay guys I started the day by getting some longer bolts; I changed them to 1 1/2" 1/4" - 20 flat head, the reason for this was to raise up the wing nuts above the 1" L stock w/ some brass tube I cut into 1" sections to make stand offs.

Then I bent the inside L stock to shape making my marks 1/4" less than before so it would fit inside w/ a gap for the nuts from the hing bolts.

Then w/ 1/8" shims on the long sides I clamped them in place and marked where I wanted my wing nut standoffs to be positioned and drilled them on the drill press.

Then I put them back into the frame and used a dead center drill to get there exact position for the main frame, then I unscrewed the hinges and took the frame to the drill press and finished drilling the 1/4" holes.

After that I put the center frame back in place w/ shims into the main frame and flipped it over and drilled the counter sunk holes for the heads of the bolts.

There's still more yet to do, I had to stop and eat and cut more brass tubing to 1" pieces while sitting down for a rest.

I've also ordered four sheets 4'x 8' x 0.030 of PETG or Vivak clear plastic it should be here next week.

I also removed mold from the fiberglass canopy it came right out of the mold the plaster could be used again.

Check the progress, and feel free to ask questions.
If you want captions w/ the photos check waterplanes on RCG.

Bruce

splinterz25

Okay today I continue to make the frame work so far I've made it so you can pull two sizes one is the full size 17"x 21" the second is 17" x 12" the box can be made two sizes smaller yet by making two more cross L brackets. ( I laid a piece of scrap across in one photo to show this)

I'll make those as needed and I'll need to pick up a small piece of 1/8" x 1" ALUM stock for the bottom of those cross pieces to make them come out flush against the pegboard.

So after getting that finished I ran some more test to see if there was enough suction coming from my VAC. (make sure you clean or replace the filter)
I'm using a Craftsman shop vac. and it seem to be quite adequate w/ pull; but to be sure I taped a piece of paper over the unused area and ran tape around the seam of the pegboard.

Then turned on the vac. and used a sheet of printer paper to how it would pull it down.

The real test will be when I get the plastic gets here I hope as soon as the heating element.

I then started to prep. the steal sheet for the heat box by buffing it to a high luster w/ my car buffer and car wax ; this will reflect the heat even better when I build the box.

Check it,

splinterz25

Alright guys and gals this is what I've done this morning,
first I've decided to not use hinges for the frame and I'll be making another handle
for the other side and skinning them w/ 3/4 ceder to keep the fingers from burning.

The reason for taking the hinges off is this when forming tall pieces 4" or 5" the hot plastic needs to come straight down on to the plug to get a good pull.

If I were to have a bunch of small pieces I would then screw them back in.

The heater element I bought is really nice w/ the dial heat control;I'm not going to try and explain everything just have a look and if you have questions just ask.

Check it out,

Bruce

splinterz25

Well while waiting on the plastic and since were having a party/cook out this weekend; I took some time and cleaned the shop this weekend.

Then this morning I moved all the bits & pieces of the BV-138 build up stairs to the build room and the PBY build down stairs to get it ready for silk, dope & primer.

I over did it though this weekend and pulled something in my back so the rest of the day I'll work in my chair working on cutting out the fiberglass canopy's windows.

Check it out I haven't had this much room in the shop since I first made it into a shop LOL.

splinterz25

I've been busy preparing for our cookout/ party these last few days and I be back on the build and working on plugs come Monday. []


Bruce

splinterz25

Guys I'm working on the Vac-U-Box but the plugs ready for the next test
maybe tomorrow; I'm confident it's going to work.

Bruce

splinterz25

HERE'S WHERE ..THE VAC-U-BOX IS.

After a few tries w/ different sizes and heat it worked.

But I think on the PBY plug I'll use a very light coat of NOVIS plastic polish to help the release.

I now can pull FOUR different sizes the smallest be a sheet 11.5 x 12 that one was to small for this plug being so tall and I'm using 0.030 plastic.

I used all of the suggestions I received from everyone the best one being to turn the plug against the rec. shape SO THE CORNERS DO NOT LINE UP.

Thanks Willsonman,

If or when you ever go to try to pull something have a LOT of extra plastic so you can play around w/ the temp and height of the sheet from the heat source to get it to sag w/ out touching the burner.

That's it for this test subject the next will be the PBY's plug I may be able to get to it on Sunday and that would be better to let the plug's epoxy paint harden even more.

SO ANYWAY CHECK IT OUT,

Bruce

Boomerang1

I'm thinking about remaking my vac form box after using another modellers set up.

I was considering a rectangular box to suit the canopy I have to mould but it was interesting
to hear about having a lot of extra plastic around the plug. It seems a waste but is it needed
to ensure the top of the canopy has enough thickness?

One thing I will copy from this other unit is the heater arrangement. This will be on top of the
vacuum box facing downwards supported by 4 rods. The frame for holding the plastic will slide
up & down on the rods which are attached to the vacuum box. When the plastic is hot enough
(on the unit I used you could judge the amount of sag) the frame holding the plastic slides down
the rods which keep the frame in alignment with the vacuum box. A couple of magnets holds the
frame up while the plastic heats up, when hot enough just slide the frame straight down.

Do you have the shop vac running as you flop the plastic over the plug or do you use a foot switch
or something to start the vacuum once the plastic contacts the plug?

I'm using a garden blower/vac for suction.

John.

splinterz25

HAPPY 4th of JULY everyone!
A big thanks to those who have served this country!!

splinterz25

John... GREAT QUESTIONS..... I had seen that type of design w/ the four rails and may add that still to mine at a later date.

But for now this should work just fine, I tried smaller pieces of plastic and there wasn't enough plastic to stretch over the plug; I may not have gotten it hot enough though.

Anyway w/ the larger piece the canopy stays very thick after pulling it into shape.

I just use my hand to throw the vac switch just before I pick up the frame and then press straight down on to the Vac Box.

Thanks for following along and keep the questions and ideas coming they really help me think and keeps me on my toes.

Bruce