As a kid, I was always fascinated with the nosecone shape of the Honest John. I think I may have had an Estes kit back in the 1960's.
I decided to see if I could build a scratch-built 6" dia. Honest John. The first hurdle was the unique nosecone. I checked a couple of local woodworkers to see if they could turn the nosecone in basswood or something similar. The quotes for this 38" long nosecone, which changes diameter from 6" at the base to a maximum of about 8", ranged from $300 to almost $500. That was a non-starter.
So- I decided to try to turn- or rather to sand down- the nosecone from 1" thick concentric pieces of foam board. I would add some nose weight of BB's and epoxy somehow.
I had no lathe so I jury-rigged something I could use as a sanding lathe from some boards laying around, and used a hammer drill as the power source. My original thought was to sand/turn the entire 38" length at once, but the flexing of the 3/8" all-thread central rod made that impossible. So I decided to turn it in sections: the bottom 14" is pretty much straight from the 6" body tube to the 8" max. diameter; and the remaining 24" of the 3:1 ogive shape in 12", 6" (which will contain the nose weight) and 6" sections. I ended up using about a 32" section of threaded rod as the central turning point.
I laid out the 24" long 3:1 ogive curve on a 1" x 6" board, cut the curve, and epoxied 60 grit sandpaper to the curve. The trick would be to line up each of the three aforementioned 12", 6" & 6" sections accurately on the threaded rod so that the sanded curve would be accurate. I started with an 8" plywood disk as a template stop so that I would sand no more than the 8" maximum diameter. I then cut plywood disks of the minimum diameter of the previous section, to be used as a template stop for the next section's maximum diameter.
The bottom 14" of the nosecone was simpler- a 6" plywood disc which matched the diameter of 6" Blue Tube, an 8" plywood disk which would be the max. diameter of the nosecone, and the 14" of foam board sandwiched in between. I epoxied 60 grit sandpaper to a straight piece of wood to sand down to the "stops" created by the plywood disks.
So far- so good. The only section left to sand/turn is the top 6" section. I needed a break, as so far this work took maybe 10 hours total- mostly because I didn't do a good job of locking the pieces on the central threaded rod. Every time they spun out of position, I would have to reset in order to keep the ogive curve consistent.rod. After the first sanding of the bottom 14 inch "not-curved" section, the sanding dust was so bad that I had to build a plastic sheeting containment for the sanding area.
DEFINITELY wore a dust mask during the hours of sanding.
I decided to see if I could build a scratch-built 6" dia. Honest John. The first hurdle was the unique nosecone. I checked a couple of local woodworkers to see if they could turn the nosecone in basswood or something similar. The quotes for this 38" long nosecone, which changes diameter from 6" at the base to a maximum of about 8", ranged from $300 to almost $500. That was a non-starter.
So- I decided to try to turn- or rather to sand down- the nosecone from 1" thick concentric pieces of foam board. I would add some nose weight of BB's and epoxy somehow.
I had no lathe so I jury-rigged something I could use as a sanding lathe from some boards laying around, and used a hammer drill as the power source. My original thought was to sand/turn the entire 38" length at once, but the flexing of the 3/8" all-thread central rod made that impossible. So I decided to turn it in sections: the bottom 14" is pretty much straight from the 6" body tube to the 8" max. diameter; and the remaining 24" of the 3:1 ogive shape in 12", 6" (which will contain the nose weight) and 6" sections. I ended up using about a 32" section of threaded rod as the central turning point.
I laid out the 24" long 3:1 ogive curve on a 1" x 6" board, cut the curve, and epoxied 60 grit sandpaper to the curve. The trick would be to line up each of the three aforementioned 12", 6" & 6" sections accurately on the threaded rod so that the sanded curve would be accurate. I started with an 8" plywood disk as a template stop so that I would sand no more than the 8" maximum diameter. I then cut plywood disks of the minimum diameter of the previous section, to be used as a template stop for the next section's maximum diameter.
The bottom 14" of the nosecone was simpler- a 6" plywood disc which matched the diameter of 6" Blue Tube, an 8" plywood disk which would be the max. diameter of the nosecone, and the 14" of foam board sandwiched in between. I epoxied 60 grit sandpaper to a straight piece of wood to sand down to the "stops" created by the plywood disks.
So far- so good. The only section left to sand/turn is the top 6" section. I needed a break, as so far this work took maybe 10 hours total- mostly because I didn't do a good job of locking the pieces on the central threaded rod. Every time they spun out of position, I would have to reset in order to keep the ogive curve consistent.rod. After the first sanding of the bottom 14 inch "not-curved" section, the sanding dust was so bad that I had to build a plastic sheeting containment for the sanding area.
DEFINITELY wore a dust mask during the hours of sanding.