Just Sharing This Analogue 70MHz IF Loop receiver

Captain Jack said:
My shaft also looks like it's not moving very far. Don't know if it's seized completely (and why the cog failed) or what... Is that the inside of the Venture?

Did you put the Venture motor on the 36" jack? How's it been?
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Yes, that was inside CJ, I angle grinded a section out to see as the shaft was scrap anyway, plus the shaft had about 5mm of play. I grafted it to a 24inch Superjack shaft. It's a spare now CJ, but it was working well on the bench. Also another picture of the Venture shaft, the tape line denotes the play from the plastic collar. Why it's rusted so badly I don't know as the bellows were in perfect condition.20250103_195221.webp
 
scopus said:
Yes, that was inside CJ, I angle grinded a section out to see as the shaft was scrap anyway, plus the shaft had about 5mm of play. I grafted it to a 24inch Superjack shaft. It's a spare now CJ, but it was working well on the bench. Also another picture of the Venture shaft, the tape line denotes the play from the plastic collar. Why it's rusted so badly I don't know as the bellows were in perfect condition.View attachment 163115
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If the end has a gaiter on it then it can only be condensation has built up inside. Since there is a hollow gap which exands and contracts through use then there is always fresh humidity in there

Btw. Arkivator had a nice modification for their actuators, a metal umbrella that bolted over the top rose joint
 
Channel Hopper said:
If the end has a gaiter on it then it can only be condensation has built up inside. Since there is a hollow gap which exands and contracts through use then there is always fresh humidity in there

Btw. Arkivator had a nice modification for their actuators, a metal umbrella that bolted over the top rose joint
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Possibly, but also a design issue as the motor and housing can be removed leaving the shaft on the dish. Looking at guts of it after cutting a hole in the shaft, you can see some sort circular bung attached to the main worm shaft to which all the rust gunk has accumulated as the drain holes are the other side of it next to the motor. I think some sort of drainage holes are needed the other side instead, plus that would aid lubrication as their is no way you can lubricate the worm drive. I was also told they couldn't be lubricated by Rick Caylor who is a Venture dealer over in the States.
 
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Captain Jack said:
Is there a way to disassemble the worm drive without angle grinding the thing?
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Not that I could see CJ. Perhaps you could drill a couple of hole at either end of the shaft for drainage and lubrication. I know we've had these Jacks a while, but to be honest I was expecting them to last longer, considering what we paid!
 
scopus said:
Not that I could see CJ. Perhaps you could drill a couple of hole at either end of the shaft for drainage and lubrication. I know we've had these Jacks a while, but to be honest I was expecting them to last longer, considering what we paid!
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All greased surfaces hold moisture and it eventually pools to the lowest level which is where the venting hole should be drilled.

The ball screw design is designed to churn up the grease at the same time as providing close tolerances.
Do you have numbers on the bearing cases that can be read ?
 
Channel Hopper said:
All greased surfaces hold moisture and it eventually pools to the lowest level which is where the venting hole should be drilled.

The ball screw design is designed to churn up the grease at the same time as providing close tolerances.
Do you have numbers on the bearing cases that can be read ?
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No, unfortunately not. The shaft went to the tip..
 
I took off the Venture jack off the dish yesterday and replaced it with an old 24" "SuperJack" I had lying around. The dish was flopped and beached, which is why the Venture snapped.

Thankfully it seems that the worm drive itself is OK - a bit squeaky, so needs some lube but otherwise moving freely. I've not taken the gearbox apart yet but I assuming it's the same cog that crumbled. Annoyingly I cannot find the two spares I had. I remember seeing them a few weeks ago and put them somewhere "safe". Only I don't know where that "safe" is... Grrr...
 
Captain Jack said:
I took off the Venture jack off the dish yesterday and replaced it with an old 24" "SuperJack" I had lying around. The dish was flopped and beached, which is why the Venture snapped.

Thankfully it seems that the worm drive itself is OK - a bit squeaky, so needs some lube but otherwise moving freely. I've not taken the gearbox apart yet but I assuming it's the same cog that crumbled. Annoyingly I cannot find the two spares I had. I remember seeing them a few weeks ago and put them somewhere "safe". Only I don't know where that "safe" is... Grrr...
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There is another bigger black cog that also had some teeth fail the last time mine seized, so I had to replace them both. The replacement wasn't cheap if I remember.
 
scopus said:
There is another bigger black cog that also had some teeth fail the last time mine seized, so I had to replace them both. The replacement wasn't cheap if I remember.
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I've not looked yet so don't know what's failed.

Either way, I don't think I'll be putting it back on as I want to try that SMO36 motor if I ever put it back together.
 
Welp, as you suspected, the big black cog has partially stripped some teeth along with a single tooth on the white one. The white one has been replaced and it seeeeeeems to be turning OK but making a horrible grinding sounding noise as it goes past the stripped teeth. Unless I can source the black cog somewhere with the same number of teeth, it's probably going in the bin. I do like a challenge though, hmmm...

The worm drive is still OK so may put a motor from another jack...
 

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Captain Jack said:
Welp, as you suspected, the big black cog has partially stripped some teeth along with a single tooth on the white one. The white one has been replaced and it seeeeeeems to be turning OK but making a horrible grinding sounding noise as it goes past the stripped teeth. Unless I can source the black cog somewhere with the same number of teeth, it's probably going in the bin. I do like a challenge though, hmmm...

The worm drive is still OK so may put a motor from another jack...
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Same as mine CJ. Rick can get you one from Venture, but it won't be cheap!
 
My Superjack 18 in lasted a good 20 years,with some greasing every other year.
I always have a spare 18 in Superjack in stock, just in case. With the weather being hot here in Cyprus, twice a year greasing helps a lot.
 
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