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Without the gaps in the reflector, you lose gain.

I'd appreciate any comments on this construction method as I have several old tv antennas with 1" square booms and lots of usable elements and aluminum mounting clips.This would make a light weight and easy to construct antenna if it functioned correctly.
Mlord and others have built using an aluminum frame, but the gaps were insulated using plastic.
I would find some grey pvc gutter ferrules, theyre perfect for 3/8" tubing, and use those in your build.

Jed does have a gapless design here :
http://www.jedsoft.org/fun/antennas/dtv/gapless.html

If I wanted to boost one particular channel's reception in the uhf portion would cutting 4 narods to 1/4 wave & putting them on the driven element help?
Definately not, and would mess things up badly. NARODs are for VHF.
 

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The elements are made with 1/4" diameter tubing,not rod as specificied in jed's design.
Because of the surface effect, theres no difference in performance between tubing and solid rod, especially for reflectors or directors.

So, you want to see the difference in performance in JEDs gapless model if all the reflectors were connected directly to a 1" boom, with say a 4" overhang on each end ? Ill have to model that a little later.
 

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So, you want to see the difference in performance in JEDs gapless model if all the reflectors were connected directly to a 1" boom, with say a 4" overhang on each end ? Ill have to model that a little later.
That will work fine. There is very little difference in the gain and SWR graphs on the 7mm version that JED has posted here : http://www.jedsoft.org/fun/antennas/dtv/gapless.html

so I wont repost the graphs.

NEC file:

Code:
CM hov15-hovzz3-RgaplessN12z2_D7mm_diffev_7mm7mm
CM 1 inch boom, connected to reflectors,  4 inch overhang added by 300 ohm
CM AGT = 1.0(0db) at 600mhz, auto-segmentation = 21, warnings about 1" boom too thick
CE
GW	1	9	0	-1.7299567	0	0	1.72995669	0	0.12
GW	2	21	0	-1.7299567	0	0	-7.6549213	5.92496063	0.13779528
GW	3	21	0	-1.7299567	0	0	-7.6549213	-5.9249606	0.13779528
GW	4	21	0	1.72995669	0	0	7.65492126	5.92496063	0.13779528
GW	5	21	0	1.72995669	0	0	7.65492126	-5.9249606	0.13779528
GW	6	21	0	-7.6549213	5.92496063	0	-1.9935984	11.5862992	0.13779528
GW	7	21	0	-7.6549213	-5.9249606	0	-1.9935984	-11.586299	0.13779528
GW	8	21	0	7.65492126	5.92496063	0	1.99359843	11.5862992	0.13779528
GW	9	21	0	7.65492126	-5.9249606	0	1.99359843	-11.586299	0.13779528
GW	10	19	0	-1.9935984	11.5862992	0	-7.3902362	16.9829528	0.13779528
GW	11	19	0	-1.9935984	-11.586299	0	-7.3902362	-16.982953	0.13779528
GW	12	19	0	1.99359843	11.5862992	0	7.39023622	16.9829528	0.13779528
GW	13	19	0	1.99359843	-11.586299	0	7.39023622	-16.982953	0.13779528
GW	14	11	0	-7.3902362	16.9829528	0	-11.721457	16.9829528	0.13779528
GW	15	11	0	-7.3902362	-16.982953	0	-11.721457	-16.982953	0.13779528
GW	16	11	0	7.39023622	16.9829528	0	11.7214567	16.9829528	0.13779528
GW	17	11	0	7.39023622	-16.982953	0	11.7214567	-16.982953	0.13779528
GW	18	61	-3.202287	-23.9076	-23.17283	-3.202287	0	-23.17283	0.1377953
GW	19	61	-3.202287	0	-23.17283	-3.202287	23.907598	-23.17283	0.1377953
GW	20	37	-3.202287	-14.02713	-17.77736	-3.202287	0	-17.77736	0.1377953
GW	21	37	-3.2022874	0	-17.777362	-3.2022874	14.027126	-17.777362	0.13779528
GW	22	49	-3.202287	-19.38854	-12.92795	-3.202287	0	-12.92795	0.1377953
GW	23	49	-3.202287	0	-12.92795	-3.202287	19.388543	-12.92795	0.1377953
GW	24	49	-3.202287	-19.14921	-8.602992	-3.202287	0	-8.602992	0.1377953
GW	25	49	-3.202287	0	-8.602992	-3.202287	19.149213	-8.602992	0.1377953
GW	26	15	-3.202287	-5.767008	-4.781024	-3.202287	0	-4.781024	0.1377953
GW	27	15	-3.202287	0	-4.781024	-3.202287	5.7670079	-4.781024	0.1377953
GW	28	35	-3.202287	-13.26264	-1.440398	-3.202287	0	-1.440398	0.1377953
GW	29	35	-3.202287	0	-1.440398	-3.202287	13.262638	-1.440398	0.1377953
GW	30	35	-3.202287	-13.26264	1.4403976	-3.202287	0	1.4403976	0.1377953
GW	31	35	-3.202287	0	1.4403976	-3.202287	13.262638	1.4403976	0.1377953
GW	32	15	-3.202287	-5.767008	4.7810236	-3.202287	0	4.7810236	0.1377953
GW	33	15	-3.202287	0	4.7810236	-3.202287	5.7670079	4.7810236	0.1377953
GW	34	49	-3.202287	-19.14921	8.6029921	-3.202287	0	8.6029921	0.1377953
GW	35	49	-3.202287	0	8.6029921	-3.202287	19.149213	8.6029921	0.1377953
GW	36	49	-3.202287	-19.38854	12.927953	-3.202287	0	12.927953	0.1377953
GW	37	49	-3.202287	0	12.927953	-3.202287	19.388543	12.927953	0.1377953
GW	38	37	-3.202287	-14.02713	17.777362	-3.202287	0	17.777362	0.1377953
GW	39	37	-3.2022874	0	17.7773622	-3.2022874	14.027126	17.7773622	0.13779528
GW	40	61	-3.202287	-23.9076	23.172835	-3.202287	0	23.172835	0.1377953
GW	41	61	-3.202287	0	23.172835	-3.202287	23.907598	23.172835	0.1377953
GW	42	9	-3.2022874	0	23.1728346	-3.2022874	0	27	0.5
GW	43	13	-3.2022874	0	23.1728346	-3.2022874	0	17.7773622	0.5
GW	44	11	-3.2022874	0	17.7773622	-3.2022874	0	12.9279528	0.5
GW	45	11	-3.2022874	0	12.9279528	-3.2022874	0	8.60299213	0.5
GW	46	9	-3.2022874	0	8.60299213	-3.2022874	0	4.78102362	0.5
GW	47	9	-3.2022874	0	4.78102362	-3.2022874	0	1.44039764	0.5
GW	48	7	-3.2022874	0	1.44039764	-3.2022874	0	-1.4403976	0.5
GW	49	9	-3.2022874	0	-1.4403976	-3.2022874	0	-4.7810236	0.5
GW	50	9	-3.2022874	0	-4.7810236	-3.2022874	0	-8.6029921	0.5
GW	51	11	-3.2022874	0	-8.6029921	-3.2022874	0	-12.927953	0.5
GW	52	11	-3.2022874	0	-12.927953	-3.2022874	0	-17.777362	0.5
GW	53	13	-3.2022874	0	-17.777362	-3.2022874	0	-23.172835	0.5
GW	54	9	-3.2022874	0	-23.172835	-3.2022874	0	-27	0.5
GS	0	0	0.0254		' All in in.
GE	0
EK
LD	5	0	0	0	2.49e7	0
EX	0	1	5	0	1	0
GN	-1
FR	0	1	0	0	600	0
RP 0 1 36 1001 90 0 5.0 10 10000 0
 

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I'm really surprised however that the parameters didn't change.
The change was very very small, and actually on the good side. Impossible to notice the change in real life viewing.

Note:
Also leave the end points of the reflectors open. Connecting the end points, with 7mm wire, causes a sharp dip in gain from 500 - 520 mhz. So a mesh in that shape would also be problematic.
 
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