RADBMX.CO.UK
Technical & Reference Section => Tech and Restoration => Topic started by: oldschoolace on January 18, 2015, 05:19 PM
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The excitement of finding my vitus soon turned into despair when it became apparent the GT seatpost in it was well and truly stuck >:(
After going through the usual gambit of oil soaking, twisting with an old stem etc i put it aside resign to the fact that one day i was going to have to take more drastic measures which would probably ruin the original chrome and possibly the whole frame as it is very light and probably not that resilient to being knocked about.
I could see the whole frame wanting to twist when i had the seatpost in a vice :shocked:
Over christmas i had time to thing about it a bit more and made plans for a bit of home brew engineeering :)
The first and most important bit was to carefully drill a neat hole in a block of aluminium with a 1 inch diameter on one side and a 7/8th diameter on the other with a defined step where the two met.
(http://i1182.photobucket.com/albums/x455/oldschoolace/Mobile%20Uploads/DSC_0983_zpsbc52904a.jpg) (http://s1182.photobucket.com/user/oldschoolace/media/Mobile%20Uploads/DSC_0983_zpsbc52904a.jpg.html)
The other side was drilled to house 4 threaded rods
(http://i1182.photobucket.com/albums/x455/oldschoolace/Mobile%20Uploads/DSC_0984_zps2d9e9adc.jpg) (http://s1182.photobucket.com/user/oldschoolace/media/Mobile%20Uploads/DSC_0984_zps2d9e9adc.jpg.html)
Next i drilled another block right through with a 7/8th bit and drilled and threaded 4 holes for the threaded rod
(http://i1182.photobucket.com/albums/x455/oldschoolace/Mobile%20Uploads/DSC_0986_zps48dbae26.jpg) (http://s1182.photobucket.com/user/oldschoolace/media/Mobile%20Uploads/DSC_0986_zps48dbae26.jpg.html)
This was then drilled thought the side to accept a 6mm steel rod and mounted over the very top of the stuck post. The side holes were used as guides to drill through the post.
When assembled the whole set looked like this
(http://i1182.photobucket.com/albums/x455/oldschoolace/Mobile%20Uploads/DSC_0964_zps5e8d3c11.jpg) (http://s1182.photobucket.com/user/oldschoolace/media/Mobile%20Uploads/DSC_0964_zps5e8d3c11.jpg.html)
(http://i1182.photobucket.com/albums/x455/oldschoolace/Mobile%20Uploads/DSC_0961_zps6d3a26ab.jpg) (http://s1182.photobucket.com/user/oldschoolace/media/Mobile%20Uploads/DSC_0961_zps6d3a26ab.jpg.html)
(http://i1182.photobucket.com/albums/x455/oldschoolace/Mobile%20Uploads/DSC_0960_zps57cda49c.jpg) (http://s1182.photobucket.com/user/oldschoolace/media/Mobile%20Uploads/DSC_0960_zps57cda49c.jpg.html)
Turning the nuts half a turn at a time and working my way round the jig took up the slack and with a few alarmingly loud cracks and pings the masking tape told me the good news and the post had started to move. Ten minutes later the post was out :daumenhoch:
(http://i1182.photobucket.com/albums/x455/oldschoolace/Mobile%20Uploads/DSC_0968_zpsfc9e7729.jpg) (http://s1182.photobucket.com/user/oldschoolace/media/Mobile%20Uploads/DSC_0968_zpsfc9e7729.jpg.html)
(http://i1182.photobucket.com/albums/x455/oldschoolace/Mobile%20Uploads/DSC_0966_zpscdae3019.jpg) (http://s1182.photobucket.com/user/oldschoolace/media/Mobile%20Uploads/DSC_0966_zpscdae3019.jpg.html)
The block were cut as thick as they were for strength and to support the very top of the seat tube which is obviously weaker with the keyhole slot. The top of the seat tube was left unmarked (appart from the previous owners attempts to remove the tube)
(http://i1182.photobucket.com/albums/x455/oldschoolace/Mobile%20Uploads/DSC_0978_zpsc82a08e3.jpg) (http://s1182.photobucket.com/user/oldschoolace/media/Mobile%20Uploads/DSC_0978_zpsc82a08e3.jpg.html)
A close up of the bottom block seated on the seat tube.
(http://i1182.photobucket.com/albums/x455/oldschoolace/Mobile%20Uploads/DSC_0970_zpscc402528.jpg) (http://s1182.photobucket.com/user/oldschoolace/media/Mobile%20Uploads/DSC_0970_zpscc402528.jpg.html)
The hole through the seat tube hardly deformed under the pressure :daumenhoch:
(http://i1182.photobucket.com/albums/x455/oldschoolace/Mobile%20Uploads/DSC_0987_zps2039c0ec.jpg) (http://s1182.photobucket.com/user/oldschoolace/media/Mobile%20Uploads/DSC_0987_zps2039c0ec.jpg.html)
Well happy :daumenhoch:
Could possibly post this on if anyone wants a try a bit like the rim jig, would have to come up with some more detailed instructions first though :)
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:4_17_5: superb work there! That's amazing mate
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I like that :4_17_5: saved blisters from the old hacksaw blade trick and the risk of cutting into the frame.
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Brilliant :coolsmiley: :daumenhoch: :daumenhoch:
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Brilliant :daumenhoch:
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top bodgin!! simple and effective. well done!
MM
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That is fookin ace Clint :4_17_5:
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Not a cannon then :-\
Marvellous bit of bodgery Clint, fookin amazes me where all these ideas come from.........
Perhaps I should stop killing my brain cells with cider n fags :chin:
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Not a cannon then :-\
Marvellous bit of bodgery Clint, fookin amazes me where all these ideas come from.........
Perhaps I should stop killing my brain cells with cider n fags :chin:
Swap them for Tuna and maxi muscle before it's too late :daumenhoch:
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Lovely bit of tinkering ;D i find that anything seized often responds to being "shocked" out so to speak, rather than building up a steady pressure. Take up the slack, put it under tension, warm the frame post with a heat gun, then give it a belt.......
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Not a cannon then :-\
Marvellous bit of bodgery Clint, fookin amazes me where all these ideas come from.........
Perhaps I should stop killing my brain cells with cider n fags :chin:
Swap it for Tuna and maxi muscle :daumenhoch:
Think I'd rather carry on killing em snoop :teef:
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Lovely bit of tinkering ;D i find that anything seized often responds to being "shocked" out so to speak, rather than building up a steady pressure. Take up the slack, put it under tension, warm the frame post with a heat gun, then give it a belt.......
I tend to buy a frame without the seat post still in it :LolLolLolLol:
Makes me want to buy one with a stuck seat post now.
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Brilliant idea :daumenhoch:
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Great bit of engineering. :4_17_5:
I bet you get a few radsters wanting to borrow that.
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(http://tapatalk.imageshack.com/v2/15/01/18/554863e8ceb8ceafc5ac4b3ecccb6efd.jpg)
TOP JOB LAD!
Sent from my iPhone using Tapatalk
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Top bodging Clinton :4_17_5:
I bet it couldn't shift 'Excalibur' from my silverfox though
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:4_17_5:
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Top bodging Clinton :4_17_5:
I bet it couldn't shift 'Excalibur' from my silverfox though
stick a pic up Griff, let's have a look :daumenhoch:
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That's excellent Clint. Well done :4_17_5:
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Awesome :4_17_5:
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Awesome as always
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Awesome!! Could double a penis enlarger also. :-\
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Awesome work yet again. :4_17_5: :4_17_5: :4_17_5: :daumenhoch:
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Very good work!! I like.
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excellent job
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Wow :daumenhoch:
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Remembered a crappy old frame I had thrown behind the shed with a stuck post. Thought I would have a go for a bit of r&d....... 2 for 2 on the removal jig :)
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Genius! Top bombing!
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That's a pretty impressive contraption you've made there :coolsmiley:
I'm surprised it hasn't put a flat on the top tube with the pushing down forces (while pulling up)
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Really great! Well Done :4_17_5:
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Nice one Clint :4_17_5:
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That's a pretty impressive contraption you've made there :coolsmiley:
I'm surprised it hasn't put a flat on the top tube with the pushing down forces (while pulling up)
It looks deceptive in the photos but the bottom block clears the top tube be about 15-20mm
All the force is exerted down the seat mast, perfectly vertically so there is no danger of it distorting the mast :daumenhoch:
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Top bodging Clinton :4_17_5:
I bet it couldn't shift 'Excalibur' from my silverfox though
stick a pic up Griff, let's have a look :daumenhoch:
No pics, but plenty tried (& failed) to get it out
Is a renthal though so has bonded itself to the steel ::)
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Challenge accepted ;)
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Awesome work again Clint. Your next task... building one for a layback. :LolLolLolLol:
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Top bodging Clinton :4_17_5:
I bet it couldn't shift 'Excalibur' from my silverfox though
stick a pic up Griff, let's have a look :daumenhoch:
No pics, but plenty tried (& failed) to get it out
Is a renthal though so has bonded itself to the steel ::)
Griff, have you tried bunging the bottom of the tube and pouring caustic soda solution down the post? I'm sure aluminium oxide is attacked by alkali solutions? Might be enough to free things up.......
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Ive been commissioned by my martian friends to build a bridge from Withington to Mars, & I've put you forward as chief engineer. :daumenhoch:
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now that's pure genius! :shocked: i wonder you... :D
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Top skills Clint, top skills :daumenhoch:
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Ingenious :4_17_5:
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great work clint :daumenhoch:
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Pure Genius.
:bow:
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Spent my lunch shaving a few mm off the jig here and there so the whole shooting match plus instructions comes in under the Royal mail 2kg weight bracket.
If anyone needs help it should cost around £3 to post out :daumenhoch:
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Top bodging Clinton :4_17_5:
I bet it couldn't shift 'Excalibur' from my silverfox though
stick a pic up Griff, let's have a look :daumenhoch:
No pics, but plenty tried (& failed) to get it out
Is a renthal though so has bonded itself to the steel ::)
Griff, have you tried bunging the bottom of the tube and pouring caustic soda solution down the post? I'm sure aluminium oxide is attacked by alkali solutions? Might be enough to free things up.......
No, because the bike's set up very nicely and that would mean pulling it all apart (& I'm a lazy fooker)
And sold the gt layback that was going to go in there
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Come on Griff let have that fooker out once and for all :D
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Come on Griff let have that fooker out once and for all :D
Maybe mk16 if I can be arsed
Tbh it's grown on me, little things like the fact it had to be oven prided in situ and even dordy couldn't pull it out have given it some sentimental value
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Can soon knock up a presentation cabinet for it. Or it can share Rich's snake post cabinet :LolLolLolLol:
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Can soon knock up a presentation cabinet for it. Or it can share Rich's snake post cabinet :LolLolLolLol:
I've still got to do something for the elina one that went in the fire at mk11 ;)
Was going to use it to display socky!
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While I think on I think it's only fair that this jig is available to site supporters only. :)