What is the best way to repair a warped dish?

[BM300]

Hello friends,

I have a prime focus 6ft DH spun dish.
It was stored wrongly by standing it on its edge insted of face down.
When sringing the strings do not meet.

Is it better to store it on its face with weigt oits back or drilling two holes on the on the longer sides and using a steel cable to pull it back to shape?

I am sure that you will have some better solutions?

Warmest regards.

​

 

[Captain Jack]

I did this with my 1.5m...

I took the dish inside into the living room, placed it face side up and strung it with 6 pieces of string (more is better). There was a massive gap in the middle between the highest and lowest one. Then I pushed the sides of the dish fairly firmly until all the strings came together. This took quite a while to work out which part of the dish was warped.

After getting it as good as I could, I turned it face down and noticed there were some small gaps still on some sides of the dish (not the whole dish was flush with the floor). So I put some weight (washed laundry!) on the sides of the dish that had a gap and some more weight on top so that the whole dish was flush and left it for an hour - but the longer the better.

Worked for me. I did the same with my 90cm Fibo.

 

[BM300]

Thank you very much for your valuable answer Captain Jack.
I will give it a go and see.

All the best.​

 

[pgh13]

I did this with my 1.5m...

I took the dish inside into the living room, placed it face side up and strung it with 6 pieces of string (more is better).

You have to be very careful with this method.....you need to explain to your missus that she's exactly the right weight to sit on it and that you don't want her to get cold outside, then maybe; just maybe, she might not notice there's a 6ft dish in the living room

 

[Archived-1]

Any pictures of your dishes please BM300

 

[midwestmac]

Hello
I was looking around for an answer to a different problem I had and saw you post,
I have a 6ft DH dish that was warped
Captain Jacks answer is g reat idea wish I would of thought of that would of saved me some time.
I think I just brought mine into the garage and tried to just push the thing in from rim to rim
but never could get it perfect. I probably didn't try hard enough.

Anyways, I saw your post and what I ended up doing was drilling holes in the rim of my dish
and made some small pieces of angle iron, drilled and bolted those to my mount ring.
I had some extra "all thread rod" is what I call it and ran it down to the ring of my mount.
Then I could tighten or loosen these "rods" were I thought it might need it, with several strings running accross the face of the dish to see
which edged was warped
On DH satellites website you've probably seen something like these rods on there big dishes, I don't if they're adjustable though.
Thats kind of were I got the idea.

Here's what it ended up looking like, the "screen" you see on the left was an experiment, I took that off. I hope the pics show up?

 

[BM300]

Any pictures of your dishes please BM300

Sorry for the late replay my friend.
Nothing special m8.
Just 7 1m dishes + 1 6ft SatAn dish connected to 2 8 or 10 output diseqC switches.
The 6ft (1.8m) SatAn dish is pointingat 16 degrees east to get both beams on that satellite.
I used to have a 14 ft H/H paraclipse but it in dismantelled and resting in the store after a very long service!​

 

[Channel Hopper]

I took the dish inside into the living room, placed it face side up and strung it with 6 pieces of string (more is better). There was a massive gap in the middle between the highest and lowest one. Then I pushed the sides of the dish fairly firmly until all the strings came together. This took quite a while to work out which part of the dish was warped.

After getting it as good as I could, I turned it face down and noticed there were some small gaps still on some sides of the dish (not the whole dish was flush with the floor). So I put some weight (washed laundry!) on the sides of the dish that had a gap and some more weight on top so that the whole dish was flush and left it for an hour - but the longer the better.

Shplendid.

If you can find a large pane of glass (a patio window for example) this can be used to determine which part of the rim requires unwarping to true up the reflector. Unfortunately the reinforcing bars will work against you in straightening everything out.