Attaching a WR42 flange to C120

[Vipersan]

Not really Rima ..the threads extend into the lnb body ..so to change it I would have to drill out and re-tap the lnb block ..
No way I want to risk that ..on a £120 lnb ..

 

[RimaNTSS]

I see, and bolts supplied with LNB were too long?

 

[Vipersan]

I see, and bolts supplied with LNB were too long?

Yes they are too long ..but not only that ...they need countersunk heads ..
As this photo shows ..
The bolt heads are sandwiched between the adapter plate ..and the C120 feed ..so they have to effectively ..vanish.
I can easily shorten a bolt ..but need a correct threaded countersunk bolt first ..x4 of course.

 

[RimaNTSS]

Holes in LNB, how deep are they? If deeper than 10mm, than, I think, it would be possible to make there another thread (very gently). Another option would be to order proper bolts with needed heads, but to order them you need to find out (measure or reed somewhere) what kind of thread is there.
Add: I would visit some professional shop and let them measure thread.

 

[Vipersan]

More money spent ..but A tool I'll use a lot I guess..
Silverline Screw Thread Pitch Gauge Combination BSW Imperial Metric Whitworth
Ebay £3.50

 

[Vipersan]

Well ..it would seem I may be correct about these threads being older than the metric system..
borrowed one from the motor on the back of a corotor ..
and yes ..it is the correct thread ..
not countersunk of course ..but the thread is compatible.

 

[RimaNTSS]

why do not you ask supplier who sod you LNB to send you free of charge proper bolts?
Nice tool, could be helpful at home (garage).
Someday I will also face adjusting-flanges issue. I have original Prodelin feedhorn but no LNB. So I will need something like Invacom flange LNB. Perhaps it is possible to join them together with only 2 bolts, another option to try to drill additional holes in the feedhorn. Third option would be to find (buy or make) adapter. There is also a question of inner diameters, whether they mach.

 

[Vipersan]

why do not you ask supplier who sod you LNB to send you free of charge proper bolts?
Nice tool, could be helpful at home (garage).
Someday I will also face adjusting-flanges issue. I have original Prodelin feedhorn but no LNB. So I will need something like Invacom flange LNB. Perhaps it is possible to join them together with only 2 bolts, another option to try to drill additional holes in the feedhorn. Third option would be to find (buy or make) adapter. There is also a question of inner diameters, whether they mach.

I doubt the supplier can help Rima ..
The lnb is I suspect quite old ..which surprised me ..
and was shipped from Canada ..via Norsat UK ..
I doubt they would just happen to have old compatible bolts lying around ..and doubtful they'd be coutersunk even if they did.
I'll just have to improvise..

 

[Vipersan]

why do not you ask supplier who sod you LNB to send you free of charge proper bolts?
Nice tool, could be helpful at home (garage).
Someday I will also face adjusting-flanges issue. I have original Prodelin feedhorn but no LNB. So I will need something like Invacom flange LNB. Perhaps it is possible to join them together with only 2 bolts, another option to try to drill additional holes in the feedhorn. Third option would be to find (buy or make) adapter. There is also a question of inner diameters, whether they mach.

Not possible to drill extra holes in the C120 flange Rima ..
Hence the need for an adapter ..

See the 2 photos ..and you'll understand why..
The only way would be to drill extra holes in the lnb body ...and the vibration might well damage the lnb ..
It would be a close call anyway ..as to wether there would be enough metal on the lnb face extending to the c120 holes..
Naa...better to try and get the right screws I think

 

[Vipersan]

Problem Solved ..
Thanks to Western Digital..
Found an old drive IDE type ..at least 6 years old..
No longer spins up So I keep it for the control board ..
Wouldn't you know it ..the Torx screws holding the control board to the drive ..are the correct thread ..and Countersunk..
Nice..
It pays not to throw stuff away ..
Ya just _never_ know..
;)

 

[RimaNTSS]

Not possible to drill extra holes in the C120 flange

I did not mean drilling extra holes but making new thread in existing holes. Good you found needed screws.
That adapter plate, did you make it yourself?

 

[Vipersan]

I did not mean drilling extra holes but making new thread in existing holes. Good you found needed screws.
That adapter plate, did you make it yourself?

Yes I did Rima ..
made from 2mm thick Aluminium..

 

[Vipersan]

Well ..it would appear that the adapted feed is as good as the dedicated XMW Ka Feed ...and marginally better than the feed made from the SL3 feeds ..
No real advantage gainwise.. seen today at 19E 16E or 7E ...
But the real advantage is that I can make more of them instead of having to import them from South Korea..at a premium.
No Idea if the all copper feed I intend to build from scratch will give me any extra ..but it just might..and when you are scratching around for extra 0.5dbs..I guess you will try anything.
The only real way to get more is a bigger dish ..but I can't see any harm in maximising what you have.
That's the nature of experiment.
;)

 

[Channel Hopper]

certainly looks a better match Llew ..
I'd like to get me one of those ..
Anyone got a spare one in their bitz box ?

Possibly, I've got some old mil-spec stuff at the back of the garage that was used for K band but I'm not sure of the exact frequency, I'd guess from the diameters it would be for 20-22GHz

 

[Vipersan]

Possibly, I've got some old mil-spec stuff at the back of the garage that was used for K band but I'm not sure of the exact frequency, I'd guess from the diameters it would be for 20-22GHz

Oooohh yes please CH ..
Nice toys for me to play with ..and it's only a few days till my birthday ..
I do love toys on my birthday..
lol