I have posted another photo detailing the adjustment mechanisim for my film jig:
http://groups.yahoo.com/group/Indoor_Construction/photos/album/1032933735/pic/873273229/view?picmode=&mode=tn&order=ordinal&start=1&count=20&dir=asc
The threaded rods are cut off #6/32, 1.5" long, machine screws. A 1/8" hole is drilled in the end of the 1/4" soft wood dowels and the threaded rods are screwed and glued (with CA) into the holes. The rails are made by gluing together two 1.5" wide, 3/16" thick medium (8#-10#) balsa sheets to form a "L" channel piece for stiffness. One can chose the rail length to fit the laongest wing one wishes to cover. Balsa blocks, 3/4" square, are glued on to provide support for the 1/4" dowels. The support block - rail combinations are drilled with a 15/64" (or 1/4" if the dowel is on the large side diameterwise) drill and the hole size is adjusted (with a file or whatever tool is handy) to provide a slight interference fit so that the dowels are kept from easily sliding by the friction fit. Often the dowel can just be pushed through the hole once to make for a good fit.
The wingnuts fit up against the blocks when the film is placed on the rails (I use chapstick to hold the film while others use vasoline or something similar). The opposite rail can be moved on the dowels to adjust for the width of film needed to cover the wing or whatever. Turning the wingnuts clockwise pushes the rail closer toward the other rail and slack is put into the film. The friction fit of the dowels is sufficient to hold the rails apart, resisting any film tension. The friction fit of the dowels and blocks is a key to how this works. If one gets the holes too large, rubber bands can be used on the dowel ends to pull the dowels together to make for more friction. Or, one can just soak the dowel in water for a bit to swell the dowel slightly. On my next jig version, I will put a slot in the end of the blocks so that I can squeeze the hole tighter for an adjustment of the friction fit.
I hope this explaination is clear enough for everyone.
Leo
--- In Indoor_Construction_at_yahoogroups.com, "John Kagan" <john_kagan@...> wrote:
>
> Leo,
>
> I don't get how the wingnuts / threaded rods interact with the dowels passing through the two sides. It looks like both sides have been slipped on the wooden dowels, and I only see the wingnuts on the ends.
>
> --- In Indoor_Construction_at_yahoogroups.com, "leop12345" <leop@> wrote:
> >
> >
> >
> >
> >
> >
> > I just added a photo of my film jig to the tool&jigs photo album:
> >
> > http://groups.yahoo.com/group/Indoor_Construction/photos/album/1032933735/pic/1834487804/view?picmode=&mode=tn&order=ordinal&start=1&count=20&dir=asc
> >
> > I think it has the same function as the Sanborn/Tyson tool but is easier to make. The rail width adjusts, after the film is applied and tightened, by turning the wingnuts. The rails are pushed closer, adding slack to the film. One can also turn the wingnuts by different amounts to fit wings/stabs where the rib curvature changes along the span.
> >
> > Leo
> >
> > --- In Indoor_Construction_at_yahoogroups.com, "Bill Gowen" <wdgowen@> wrote:
> > >
> > > Very nice!
> > >
> > > ----- Original Message -----
> > > From: dennisatyson
> > > To: Indoor_Construction_at_yahoogroups.com
> > > Sent: Saturday, April 23, 2011 8:41 AM
> > > Subject: [Indoor_Construction] Re: covering with mylar
> > >
> > >
> > >
> > > Kody,
> > > It gets even better if you have an adjustable fixture. I copied Sanborn's and consider it one of my most useful tools. You put the film on it with vasaline on the rails, pull the film tight and then lay your part on it. Then you just turn the crank handle to put slack in until the film perfectly conforms to the outline.
> > >
> > > Heres the link to my photos:
> > >
> > > http://groups.yahoo.com/group/Indoor_Construction/photos/album/1882585915/pic/list
> > >
> > > Dennis
> > > --- In Indoor_Construction_at_yahoogroups.com, Kody Priddle <pipercub0749@> wrote:
> > > >
> > > > Bill,
> > > >
> > > > Thank you very much. I think that I'll have to try that. It sounds far
> > > > more "solid" than the method that I am using right now. I didn't know that
> > > > naphtha was lighter fluid! I have a whole can of it. Now I just need to
> > > > get some 3M77.
> > > >
> > > > -Kody
> > > >
> > > > On Fri, Apr 22, 2011 at 12:43 PM, Bill Gowen <wdgowen_at_> wrote:
> > > >
> > > > >
> > > > >
> > > > >
> > > > > Kody
> > > > > Here's the link to the video. The link back to Mark's article doesn't work.
> > > > >
> > > > > http://www.thermalthumbers.com/bill-s-indoor-ramblings/f1l-construction-5-2010/covering-info
> > > > >
> > > > >
> > > > > ----- Original Message -----
> > > > > *From:* Kody <pipercub0749_at_>
> > > > > *To:* Indoor_Construction_at_yahoogroups.com
> > > > > *Sent:* Friday, April 22, 2011 11:43 AM
> > > > > *Subject:* Re: [Indoor_Construction] covering with mylar
> > > > >
> > > > >
> > > > >
> > > > > Hey Bill,
> > > > >
> > > > > Could you point me to this video? I'm always interested in alternative
> > > > > methods!
> > > > >
> > > > > Thank you,
> > > > > Kody
> > > > > Sent from my HTC Droid Eris.
> > > > >
> > > > > Bill Gowen <wdgowen_at_> wrote:
> > > > >>
> > > > >>
> > > > >>
> > > > >> Covering with Mylar is very easy. There are a lot of different ways to do
> > > > >> it. The video you saw is my version of the technique described by F1Diddler
> > > > >> in the files section of this group.
> > > > >>
> > > > >>
> > > > >> ----- Original Message -----
> > > > >> *From:* Edward <ednlois_at_>
> > > > >> *To:* Indoor_Construction_at_yahoogroups.com
> > > > >> *Sent:* Friday, April 22, 2011 10:42 AM
> > > > >> *Subject:* [Indoor_Construction] covering with mylar
> > > > >>
> > > > >>
> > > > >>
> > > > >> This is one of the toughest parts of indoor, covering. I was at a web site
> > > > >> where someone was covering with mylar & was using 3M77 in a "little" plastic
> > > > >> container mixing it with a solvent and putting it on a stab. with a brush,
> > > > >> then it was over! It said this process was on Indoor Construction but I
> > > > >> cannot find it. These guys with the F1Ds that look like they were covered
> > > > >> with moulded Mylar must be able to leap tall buildings in a single bound!
> > > > >> Help.....please.
> > > > >> Ed Berton
> > > > >> Brevard, NC
> > > > >>
> > > > >>
> > > > >
> > > >
> > >
> >
>
Received on Sun Apr 24 2011 - 07:32:48 CEST