Beginner scratchbuilding/plastic fab question
 

All,

I'm about to start on fab of an internal antenna for my PZ III. I'll be using styrene sheetstock and tubing. My question is what would be the preferred sheetstock thickness and method for cutting the sheet? As for the cutting would it be score with an exacto blade, etc then break? All input appreciated.

Thanks all for curing my ignorance.

Frank

RE: Beginner scratchbuilding/plastic fab question
 

If you do a search for antenna mod you will see how I made my internal antenna coils to replace the non scale external antennas on the HL tanks. The thread shows how and where I mounted my internal antenna mod.
here's the link http://www.rcuniverse.com/forum/m_71...tm.htm#7195692
As for cutting sheet styrene you can score and then snap or use a razor saw(zona saw). Since no actual stress will be applied to the mount .030-.040" styrene can be used or just hot glue the antenna coil to the side wall of the tank

RE: Beginner scratchbuilding/plastic fab question
 

Thanks Mr Pzrwest for the info on styrene fab and also the link to your antenna post.

Frank

RE: Beginner scratchbuilding/plastic fab question
 

I just finished moving my antenna into the hull of my HL Pz3 by wrapping 22-guage wire (approx9.5 inches)around a pencil, which I then cut to length. I then soldered it to the Rx board's existing antenna lead, covered with shrink wrap, and mounted the new load coil vertically in the hull next to the smoke unit using silicon adhesive. It's just over 1 inch long and fits with plenty of space to spare. I'll post a pic if you'd like.

RE: Beginner scratchbuilding/plastic fab question
 

A small table top band saw or scroll saw is great for cutting shapes in heavier gauge styrene. nd one tool that i will be getting sooner or later is a table top belt/disc sander for shaping and profiling parts. You can change the angle of the surface to creat bevels and curves.

RE: Beginner scratchbuilding/plastic fab question
 

Hondobob,

I would be very interested in a picture. Maybe your approach is worth considering. Have you confirmed the range yet?

Frank

RE: Beginner scratchbuilding/plastic fab question
 

My solution isn't nearly as elegant as others but it seemed to work okay for my little Panzer 3.

The only material I needed was some 22-guage wire, a standard number 2 pencil, a tape measure (though a wood rule would also work), and wire cutters/strippers.
http://i180.photobucket.com/albums/x...3_Antenna4.jpg

Heng Long tanks operate just above 27MHz, which has a wavelength of approx432 inches (approx 11m), and their stock antenna length is about 9 inches (22.86cm), which makes them about 1/48 wavelength (equal to7.5 degrees of a sinusoid). This isminimalto support very short range AM reception, which is all these tanks need. My Pz3 operated very well to distances of 90+ feet with the stock antenna. To test the sufficiency of replacing the antenna with an electrically equal length load coil I simply wrapped the proper lenght of wire around the pencil (you must use a non-ferrous core for antennas) and attached it to the stock antenna mount.
http://i180.photobucket.com/albums/x...3_Antenna5.jpg

No surprise, the new load coil performed the same as the stock antenna. I then trimmed the excess pencil core, soldered the coil to the Rx board antenna wire,and vertically mounted the coil to the hull next to the smoke unit using some standard rtv silicon adhesive. Performance remained unchanged.
http://i180.photobucket.com/albums/x..._Antenna11.jpg

I'm the only one who will ever see it so I'm not overly concerned how it looks, just how well it works. If I later decide the improve it's looks, I'll likely just cover it in a nice layer of stylish shrink wrap.