Scott and Tim: The Bowlus molds were supposedly of concrete for the plywood body (kit version). I am not sure if the same huge concrete molds were used for the fiberglass version. Several years ago in the Bungee Cord, VSA newletter, someone remarked that these molds were abandomed under a freeway overpass not far from the old Bowlus plant. Urban Rumor? regards, Jim
On Thu, 19 Jan 2006 09:04:54 +0000, "Tim Bennett" wrote: > Scott, > I was going through old posts this morning and found yours. There has been > no response so I am offering my knowlege in answer to the "how did they do > it in full scale" question. On a visit to the Spruce Goose Museum in Long > Beach several years ago I saw an extensive photographic display that > explained the plywood technology employed in that aircraft that was > supposedly the state of the art at the time of the Spruce Goose project. I > think the British Lancaster Bomber was built in a similar manner. What they > did was build steel male and female mold sets in the shape of the curved > parts they needed. Wood veneers were steamed and glued then laid up in the > molds cross grain in multiple layers. This was cured under steam heat and > pressure until the glue set. A smooth curved part was removed from the mold > ready to be trimmed and fastened to the framework of the structure. The > trick is that the wood was not plywood until after the curve was > established. They had photos of parts that appeared to be about 1/2 inch or > less thick with people standing on the high point of the curve with little > appearant deflection. These things were very stiff and strong. > > I hope this helps. > > Tim Bennett > > ----- Original Message ----- > From: "Scott Hinckley" <[EMAIL PROTECTED]> > To: <soaring@airage.com> > Sent: Saturday, January 14, 2006 2:28 PM > Subject: [RCSE] Gull wing sheeting with ply > > > >I have several 1/4 scale plans for 1930's sailplanes with gull wings. > > Some have a sharp line > > (no curve) in the spar between the sections, and at least one has a > > nicely laminated curved > > spar transitioning between the sections. I have read that the curved > > transition is most correct. > > The wings are generally sheeted with .4mm (1/64") ply, which doesn't > > allow enough > > thickness for blending after sheeting. > > > > What is the technique for sheeting a curved transition with 1/64 ply? > > It seems that it would > > not conform easily to the compound curve. How did they do it on the > > full size wood > > sailplanes? > > > > > > Scott Hinckley > > > > __________________________________________________ > > Do You Yahoo!? > > Tired of spam? Yahoo! Mail has the best spam protection around > > http://mail.yahoo.com > > RCSE-List facilities provided by Model Airplane News. Send "subscribe" > > and "unsubscribe" requests to [EMAIL PROTECTED] Please note > > that subscribe and unsubscribe messages must be sent in text only format > > with MIME turned off. Email sent from web based email such as Hotmail and > > AOL are generally NOT in text format > > > RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format > > Jim Ealy Education by Demonstration RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
