Centurion Bridgelayer

Forum for discussion relating to the Centurion
Phil Woollard
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Re: Centurion Bridgelayer

Post by Phil Woollard » Fri Nov 16, 2018 3:18 pm

It's sooo big! I love it, keep the pics coming David. If you briefly edit the photos they should end up the right way up! :)
Mechanical engineer, Pyrotechnic technician, and small time farmer.
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Robert E Morey
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Re: Centurion Bridgelayer

Post by Robert E Morey » Fri Nov 16, 2018 5:09 pm

Dang that is huge! Love the picture - really puts it into perspective how tall that is! Fantastic work!
Bob

David Skeldon
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Re: Centurion Bridgelayer

Post by David Skeldon » Mon Nov 26, 2018 11:58 am

Hi.
Testing bridge and recovery.
https://youtu.be/tUAFT6fasMU

David

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Stephen White
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Re: Centurion Bridgelayer

Post by Stephen White » Mon Nov 26, 2018 1:04 pm

David, always impresses every time I see it. Great video too. Awesome skills.

It always seemed to take an age to launch a bridge and then the Sappers faffed around proving the route it and marking the entry and exit lanes., If you were first across, you knew you were in for a long, cold wait but you were also in for a kicking if, when they declared it open, you were kipping. The joys of assault river crossing. There was always a need to remind your driver not to be too enthusiastic with the throttle as you came off the bridge. On the one occasion I saw that happen, the quick burst of acceleration revved up the tracks and smartly kicked the bridge back into the river. Feel silly? On another occasion, they'd laid it in a hurry and failed to level the exit bank, which was a breach in a bund. We went over and at the point we should have been leaving the bridge, I got a falling sensation. About six feet. Bang. Remarkable how robust the Chieftain suspension was. Not so for the crew however.

Thanks for reminding me.

Stephen

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Adrian Harris
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Re: Centurion Bridgelayer

Post by Adrian Harris » Mon Nov 26, 2018 1:24 pm

Looks super smooth.

More lead acid batteries needed in the hull at 3:30 though !!

Adrian.
R.I.P Margaret I.L.Y

David Skeldon
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Re: Centurion Bridgelayer

Post by David Skeldon » Mon Nov 26, 2018 1:32 pm

Hi.
Yes i need to stop the back end lifting so much. I am using smaller batterys this time so not so much internal weight. When i do the external fuel tank i will probably put some weights in it.

David

Phil Woollard
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Re: Centurion Bridgelayer

Post by Phil Woollard » Mon Nov 26, 2018 3:20 pm

Just seen the video David and it looks great,your patience is exceptional and it really shows! Regards Phil.
Mechanical engineer, Pyrotechnic technician, and small time farmer.
Youtube channel, Magpiespyro. For 1/6th scale video action!
Email; magpiespyro@hotmail.com

David Skeldon
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Re: Centurion Bridgelayer

Post by David Skeldon » Thu Jan 24, 2019 1:33 pm

Hi
Now all back together.

David
Attachments
IMG_20190124_121011~3.jpg
IMG_20190124_120905~3.jpg

Frank Breitenbach
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Re: Centurion Bridgelayer

Post by Frank Breitenbach » Fri Jan 25, 2019 8:26 am

Hello David
A real perfect model!
Kind regards
Frank

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Adrian Harris
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Re: Centurion Bridgelayer

Post by Adrian Harris » Sat Oct 12, 2019 3:28 pm

So, at the South West Model Show at Bovington, I had some performance issues :shock: :oops: :shock: and wasn't able to get the bridge up to more than half mast (45 degrees). Cue the usual jokes about 'semis' and comments as to where to insert the viagra :lol: :lol:

After running through all the electronics, hydraulics and anything else we could think of, Chris Fry spotted that one of the ram shafts was bent:

20191006_110055-reduced.jpg

Even though the ram would extend and retract without the bridge attached, it was audibly struggling as the bend passed through the end seal, and the added weight of the bridge meant the system stalled at the point that the ram tightened up.

I attempted to straighten the ram in situ using some angle iron, 3d printed spacers and a large G clamp, but only succeeded in bending the tommy bar on the clamp. Today I gave up trying to fix it in situ and removed the ram from the cylinder, thinking I could use my 1 ton bench vice to ease it straight.

No dice; once I started adding significant force, something in the work holding gave way and the whole thing sprang apart.

So, given that Plan B was to buy a complete replacement cylinder, I decided to trust in the power of the Norse gods...

20191012_150709a.jpg

So, working up from gentle taps to something somewhat more violent, I succeeded in straightening the ram, without marking the shaft.

Having reinstalled everything, the ram seems to move freely, without the juddering which was happening before.

Unfortunately, the weather is too dismal for me to build the bridge and test it.

As with some jobs on these tanks, it fought back:

20191012_150741a.jpg

But seeing as there is hydraulic fluid all over the floor, I think this match ended as a one all draw.

The irony is not lost on me that, now the ram has been out of the cylinder, I need to bleed the whole system :roll:

Adrian.
R.I.P Margaret I.L.Y

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Stephen White
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Re: Centurion Bridgelayer

Post by Stephen White » Sat Oct 12, 2019 3:34 pm

Who says we don't suffer for our hobby? Looking forward to seeing another erection raising of the bridge at Abingdon. Glad you were able to get the ram to see sense. It proves the old engineering adage that when in doubt, select a bigger tool. Works in all sorts of contexts........

Steve Stuart
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Re: Centurion Bridgelayer

Post by Steve Stuart » Sat Oct 12, 2019 10:42 pm

Archimedes is the man. Levers, fulcrums and most importantly brain power! So all credit to Adrian!
Steve

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