Re: Making the TFF Aerial
Posted: Sun Jul 15, 2012 12:36 am
Part 2.
..Many thanks again for all the nice comments..and I've taken everything on board with regards to the question of pillars or otherwise.
I agree with you Nobby, that they can put a costly kink in the line and have also been thinking about luckyluca's idea of an optional 'wraparound' band. In fact, I think we have this problem solved now, thanks to your suggestions; -more of that later..
Have been making some progress with the backplate this week. It's still nowhere near complete but here is what's been happening. Fishing on the River Yealm has been completely knocked out for a while,-at least, where I go. Not only did we have the highest floods on record last Friday, which did dreadful damage and made National news, there has also been a big problem with sewage flowing into it! I haven't been there to see it but it's not good news and safe to say that it will be a while before anything like normal service can be resumed..
..But getting back to the backplate; I thought we could utilize the piece of tufnol left over from the Coxon project, for making the centre section element. Also, the side plates are now fully dried and ready for further work.
![Image](http://i140.photobucket.com/albums/r3/watermole/Reelbackplatecomponents.jpg)
I sawed off the end part by hand, then started rough-turning the tufnol to thickness, plus 0.050" for finishing. I also put a 3/16" pilot drill through..
![Image](http://i140.photobucket.com/albums/r3/watermole/Turningthetufnol.jpg)
..and recessed the back to accept the reinforcing ring and laminate plate..
![Image](http://i140.photobucket.com/albums/r3/watermole/Puttingintheouterrecess.jpg)
The reinforcing ring was turned from a piece of bronze; an old scrap bush from a machine, acquired very cheaply..
![Image](http://i140.photobucket.com/albums/r3/watermole/Thereinforcingring.jpg)
..and parted off..
![Image](http://i140.photobucket.com/albums/r3/watermole/partedoffjpg.jpg)
The surface finish is deliberately left rough so that the glue will key into it better.
![Image](http://i140.photobucket.com/albums/r3/watermole/andreadyforgluingjpg.jpg)
Here you see the ring now glued into place-
![Image](http://i140.photobucket.com/albums/r3/watermole/Gluedintoplace.jpg)
Again, I have used Araldite for this. After gluing, a quick blow with an old hairdryer to warm it, does wonders for making the glue flow nicely into and around all the material. I will leave that for at least one day before further machining. In the meantime, the inner-and outer laminate plates were trimmed with a hacksaw and the outsides turned true.
![Image](http://i140.photobucket.com/albums/r3/watermole/Innerandouterlaminates.jpg)
![Image](http://i140.photobucket.com/albums/r3/watermole/beingturnedtruejpg.jpg)
The outer was all ready to be glued into place..
![Image](http://i140.photobucket.com/albums/r3/watermole/Theouterlaminateready.jpg)
..but then I had a bit of an idea! Whilst looking through the box of wood off-cuts for something suitable to make the back from, I came across these two little scrap strips of real ebony..
![Image](http://i140.photobucket.com/albums/r3/watermole/Ebonyidea.jpg)
...and thought that, as it is a special project, we just might allow ourselves a little excess, decoratively speaking! I've never tried to do anything like this before so it all might go horribly wrong, in which case, we start again. It's an idea inspired by my old BSA tank badges..
Using a very crude, but surprisingly accurate (for this job) method of division, we produced a concave form on the end of each mahogany segment.
![Image](http://i140.photobucket.com/albums/r3/watermole/Scallopingthe12facets.jpg)
The set-up was very basic. A piece of wood with a hole in it held in the vice. The laminate was held by a screw and washer in the hole and division obtained by indexing to the two panel pins tapped into the wood to act as markers. The 'cutter' was a 1 1/4" diameter grinding stone held in the electric drill!
As the rough sawn pieces of ebony were about 1/4" thick, the first thing was to try and cut the thickness in half by sawing down the middle. It wasn't terribly accurate, but good enough for purpose..
![Image](http://i140.photobucket.com/albums/r3/watermole/Sawingtheebonyintohalves.jpg)
The pieces were then further divided by sawing into small lengths and planing flat on one side and drilling a small hole in the middle..
![Image](http://i140.photobucket.com/albums/r3/watermole/andintosmallpiecesjpg.jpg)
..which were then turned to 1 1/4" diameter by mounting on a simple arbor and clamping with a screw and washer.
![Image](http://i140.photobucket.com/albums/r3/watermole/forturningtotherightsizejpg.jpg)
These were then cut again into little segments of arc, which will be glued into place on the laminate.
![Image](http://i140.photobucket.com/albums/r3/watermole/andsawingintosectionsjpg.jpg)
You can probably guess what happens next but will post some pictures of the result next time..
With regards,
wm+
..Many thanks again for all the nice comments..and I've taken everything on board with regards to the question of pillars or otherwise.
I agree with you Nobby, that they can put a costly kink in the line and have also been thinking about luckyluca's idea of an optional 'wraparound' band. In fact, I think we have this problem solved now, thanks to your suggestions; -more of that later..
Have been making some progress with the backplate this week. It's still nowhere near complete but here is what's been happening. Fishing on the River Yealm has been completely knocked out for a while,-at least, where I go. Not only did we have the highest floods on record last Friday, which did dreadful damage and made National news, there has also been a big problem with sewage flowing into it! I haven't been there to see it but it's not good news and safe to say that it will be a while before anything like normal service can be resumed..
..But getting back to the backplate; I thought we could utilize the piece of tufnol left over from the Coxon project, for making the centre section element. Also, the side plates are now fully dried and ready for further work.
![Image](http://i140.photobucket.com/albums/r3/watermole/Reelbackplatecomponents.jpg)
I sawed off the end part by hand, then started rough-turning the tufnol to thickness, plus 0.050" for finishing. I also put a 3/16" pilot drill through..
![Image](http://i140.photobucket.com/albums/r3/watermole/Turningthetufnol.jpg)
..and recessed the back to accept the reinforcing ring and laminate plate..
![Image](http://i140.photobucket.com/albums/r3/watermole/Puttingintheouterrecess.jpg)
The reinforcing ring was turned from a piece of bronze; an old scrap bush from a machine, acquired very cheaply..
![Image](http://i140.photobucket.com/albums/r3/watermole/Thereinforcingring.jpg)
..and parted off..
![Image](http://i140.photobucket.com/albums/r3/watermole/partedoffjpg.jpg)
The surface finish is deliberately left rough so that the glue will key into it better.
![Image](http://i140.photobucket.com/albums/r3/watermole/andreadyforgluingjpg.jpg)
Here you see the ring now glued into place-
![Image](http://i140.photobucket.com/albums/r3/watermole/Gluedintoplace.jpg)
Again, I have used Araldite for this. After gluing, a quick blow with an old hairdryer to warm it, does wonders for making the glue flow nicely into and around all the material. I will leave that for at least one day before further machining. In the meantime, the inner-and outer laminate plates were trimmed with a hacksaw and the outsides turned true.
![Image](http://i140.photobucket.com/albums/r3/watermole/Innerandouterlaminates.jpg)
![Image](http://i140.photobucket.com/albums/r3/watermole/beingturnedtruejpg.jpg)
The outer was all ready to be glued into place..
![Image](http://i140.photobucket.com/albums/r3/watermole/Theouterlaminateready.jpg)
..but then I had a bit of an idea! Whilst looking through the box of wood off-cuts for something suitable to make the back from, I came across these two little scrap strips of real ebony..
![Image](http://i140.photobucket.com/albums/r3/watermole/Ebonyidea.jpg)
...and thought that, as it is a special project, we just might allow ourselves a little excess, decoratively speaking! I've never tried to do anything like this before so it all might go horribly wrong, in which case, we start again. It's an idea inspired by my old BSA tank badges..
Using a very crude, but surprisingly accurate (for this job) method of division, we produced a concave form on the end of each mahogany segment.
![Image](http://i140.photobucket.com/albums/r3/watermole/Scallopingthe12facets.jpg)
The set-up was very basic. A piece of wood with a hole in it held in the vice. The laminate was held by a screw and washer in the hole and division obtained by indexing to the two panel pins tapped into the wood to act as markers. The 'cutter' was a 1 1/4" diameter grinding stone held in the electric drill!
As the rough sawn pieces of ebony were about 1/4" thick, the first thing was to try and cut the thickness in half by sawing down the middle. It wasn't terribly accurate, but good enough for purpose..
![Image](http://i140.photobucket.com/albums/r3/watermole/Sawingtheebonyintohalves.jpg)
The pieces were then further divided by sawing into small lengths and planing flat on one side and drilling a small hole in the middle..
![Image](http://i140.photobucket.com/albums/r3/watermole/andintosmallpiecesjpg.jpg)
..which were then turned to 1 1/4" diameter by mounting on a simple arbor and clamping with a screw and washer.
![Image](http://i140.photobucket.com/albums/r3/watermole/forturningtotherightsizejpg.jpg)
These were then cut again into little segments of arc, which will be glued into place on the laminate.
![Image](http://i140.photobucket.com/albums/r3/watermole/andsawingintosectionsjpg.jpg)
You can probably guess what happens next but will post some pictures of the result next time..
With regards,
wm+