OzVMX Forum
Clubroom => Tech Talk => Topic started by: cambo on August 04, 2015, 11:49:05 pm
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Hi guys does anyone have any ideas on removing dents from an aluminium fuel tank.I have seen the cut and shut method done but was hoping for easier way ,I have a 75 mx 250 b.
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send it to Geoff Morris?
cheers
Rossco (aka GMC Business Development Manager :o )
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No easy way that doesn't involve proper panelbeating, aluminium takes more skill to get right than steel as well as it stretches easier
I had my Falta tank done over here by Steve Roberts who built the Spartons & plastic fantastic F1 Suzukis. He opened up the tank at the seams as there was no way to get anything through the filler into the area that needed doing. He welded it back together as good or better than original with oxy as he's old school then leak tested it & polished it. If you've ever felt how light the Falta tank is you'll understand how big a undertaking this was due to how thin the metal is
Before
(http://i788.photobucket.com/albums/yy166/tony27_photo/CZ%20981%20random%20stuff/Falta%20tank/temporary_zps9092ef5f.jpg) (http://s788.photobucket.com/user/tony27_photo/media/CZ%20981%20random%20stuff/Falta%20tank/temporary_zps9092ef5f.jpg.html)
After
(http://i788.photobucket.com/albums/yy166/tony27_photo/CZ%20981%20random%20stuff/Falta%20tank/temporary_zps9c7f6d78.jpg) (http://s788.photobucket.com/user/tony27_photo/media/CZ%20981%20random%20stuff/Falta%20tank/temporary_zps9c7f6d78.jpg.html)
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If there shallow dents , I used to strap it to stop it spreading. Fill with water and put it in the freezer for a day.
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Thanks for all your info ill try yours first slakewell,if no joy I will check Geoff morris .cheers
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Thanks Rossco, your cheques in the mail 8)
I heard that a wise old Irishman once said that the cleverest invention of the modern world was the thermos; it could keep warm soup hot or cold drinks cold.
But the most amazing thing about the thermos was that it always knew which foods to keep hot or cold. :o
I think ice is amazing stuff, it’s great in my Bourbon and Coke but as for using it to remove dents makes me wonder how the ice knows where the dent is.
(http://i15.photobucket.com/albums/a393/gmcloa/Repairs/pipe%20rip%201_zpsee1jxs6v.jpg) (http://s15.photobucket.com/user/gmcloa/media/Repairs/pipe%20rip%201_zpsee1jxs6v.jpg.html)
(http://i15.photobucket.com/albums/a393/gmcloa/Repairs/pipe%20rip%202_zpstvchihy0.jpg) (http://s15.photobucket.com/user/gmcloa/media/Repairs/pipe%20rip%202_zpstvchihy0.jpg.html)
Don't let ice addiction ruin your life tank/exhaust.
Use it at your peril
It does make more work for me but it's not the sort of work I like chasing!
Pressurizing tanks can ruin a tank too,
The Elsinore tank on the left has been pressurized, the pressure will spread the wings of the tank while closing up the tunnel making it hard to get over the frame again, it can take a lot of work to get them looking right again
(https://www.freesites.com.au/login/members/imagemanager/images
/89fcd07f20b6785b92134bd6c1d0fa42/tank%20repairs/Tank-repair-2.jpg)
http://www.geoffmorrisconcepts.com/19/fuel-tank-repairs
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I tried pressurising a steel ts250x tank and it nearly laid out flat , I just saved it in a hydraulic press and got a half litre more in it but would not recomend doing it as the dents were still there after I fixed the problems I created.
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If you don't want to spend the money repairing it properly ie. via Geoff, your only option is bogging it and painting it. Is it a resto or race bike?
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This why you must strap your tank to use the ice method. To stop it spreading in the frame well.
I also did not use the cap. It did remove small shallow knee dents NP.
Why wouldn't compressed air and a regulator set to around 20 PSI and a heat gun work? Never tried it but the theory sounds fine to me?
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20 PSI is a hellava lot to be putting into a fuel tank!
I test my tanks for leaks with around 4-5 PSI and this small pressure starts to distort tanks (but not permanently)
It may be possible to remove some shallow dents with pressure if your lucky but dents come in all shapes and sizes and also require different force to remove.
Any dent with a crease will not come out easily as the crease increases the strength of the dent.
Also the radius of the dent effects how easily the dent will come out, small diameter deep dents will have a smaller radius which will require more force than a larger dent that has a larger radius.
They build dam (big dams/reservoirs) walls with the radius in towards the water as it has more strength this way.
I always advise against pressure as the dent will need more force to move it compared to the rest of the tank which will move easily.
A CZ / Maico tank that has flattish sides will easily become rounded (good job on that CZ tank above too BTW) but Elsinore tanks also have flattish sides that will also become more rounded by the time the dent gives in.
I have heard many stories of guys that reckon they can strap a tank down from moving but the success stories will be rare.
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Thinking aloud; a suction cup device outside and some low pressure inside for shallow dents might not be hopeless..
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2 comments - I have seen low pressure (around 5 PSI) accidents at work with carbon - you would not of wanted to have your hand in the way - be careful with pressure if you go down that route!
Secondly - agree with Geoff - had the paintless dent removal people take a dent out of the side of the car - very good job but still not what I thought it would be - guy explained that in being dented the steel stretches so is nigh on impossible to get back to the same shape.
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Aluminum is nice until you bend it. Then it becomes the world's biggest PITA.
As Geoff said, creases are strong points and they don't like moving. Usually you find the spot next to it will start distorting as soon as you try and push it.
When you get a dent it usually stretches the metal so it never goes back to the same shape. Some you can get lucky and suck them out but most are best left for the pros.
Steel is much easier to work with. Maybe leave it as a race tank and find another to have for the garage queen look.
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Well its a race bike so it might stay like it is or be bogged, as it does have a crease on a top corner.
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i dented my bsa alloy tank with a perfect edge off my garage wall, my mate is a panel beater with soft spot for vmx. After huge amounts of free beer, he agreed to fix it. after huge amount of time and effort it was fixed. he told me that if it was a paying job it would have cost $1000
first point, NO EASY FIX
second point, NO EASY FIX
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Bog is the easy fix, comes down to what you want and what dollars you can justify.
The sharp edge dents do come out, it's just time = dollars
(http://i15.photobucket.com/albums/a393/gmcloa/Repairs/Tank%20repair%20064_zpssgz6jqca.jpg) (http://s15.photobucket.com/user/gmcloa/media/Repairs/Tank%20repair%20064_zpssgz6jqca.jpg.html)
(http://i15.photobucket.com/albums/a393/gmcloa/Repairs/Elsinore%20tank%20repair%20002B_zpsihx9cqye.jpg) (http://s15.photobucket.com/user/gmcloa/media/Repairs/Elsinore%20tank%20repair%20002B_zpsihx9cqye.jpg.html)
(http://i15.photobucket.com/albums/a393/gmcloa/Repairs/Tank%20repair%20080_zpsz6a43krq.jpg) (http://s15.photobucket.com/user/gmcloa/media/Repairs/Tank%20repair%20080_zpsz6a43krq.jpg.html)
Bloody tank makes me look fat, no really it's the tank :o
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(http://i15.photobucket.com/albums/a393/gmcloa/Repairs/Tank%20repair%20067_zpsk52dravj.jpg) (http://s15.photobucket.com/user/gmcloa/media/Repairs/Tank%20repair%20067_zpsk52dravj.jpg.html)
(http://i15.photobucket.com/albums/a393/gmcloa/Repairs/Tank%20repair%20097_zpsqkrkwnhw.jpg) (http://s15.photobucket.com/user/gmcloa/media/Repairs/Tank%20repair%20097_zpsqkrkwnhw.jpg.html)
Murals are an optional extra ::)
Bloody polished tanks are hard to photograph
(http://i15.photobucket.com/albums/a393/gmcloa/Repairs/TT%20tank%20002_zpsxjaulqqo.jpg) (http://s15.photobucket.com/user/gmcloa/media/Repairs/TT%20tank%20002_zpsxjaulqqo.jpg.html)
(http://i15.photobucket.com/albums/a393/gmcloa/Repairs/TT%20tank%20013_zps8revw1ap.jpg) (http://s15.photobucket.com/user/gmcloa/media/Repairs/TT%20tank%20013_zps8revw1ap.jpg.html)
(http://i15.photobucket.com/albums/a393/gmcloa/Repairs/TT%20tank%20015_zps4gasahkk.jpg) (http://s15.photobucket.com/user/gmcloa/media/Repairs/TT%20tank%20015_zps4gasahkk.jpg.html)
A keen eye may be able to see where I cut the tanks open...
(http://i15.photobucket.com/albums/a393/gmcloa/Repairs/Elsinore%20tank%20repair%20002_zpstscse19c.jpg) (http://s15.photobucket.com/user/gmcloa/media/Repairs/Elsinore%20tank%20repair%20002_zpstscse19c.jpg.html)
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+1 for GMC's comments.
I had a YZ125C tank that was pretty rough. I learned the hard way about them spreading under pressure and then learned the hard way about the pressure collapsing the frame tunnel...
Eventually, I had a piece of 4x2" timber wrapped in rags in the tunnel, and held the lower seam in the big vice. Then I cranked the pressure up...
In hindsight, if it had let go at 100psi, it probably would have killed me, but it didn't, so that ended well.
What did happen was that the bigger, shallower dents were made smaller, and the smaller, sharper dents completely ignored me.
So then I bogged it.
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Bogged and painted tank. Needs a repaint now as modern riding pants plus knee braces have made a mess of it, but i don't have to worry about dropping it and stuffing hundreds of $ of repair work
(http://i300.photobucket.com/albums/nn38/mainline_bucket/tank.jpg)
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i dented my bsa alloy tank with a perfect edge off my garage wall, my mate is a panel beater with soft spot for vmx. After huge amounts of free beer, he agreed to fix it. after huge amount of time and effort it was fixed. he told me that if it was a paying job it would have cost $1000
first point, NO EASY FIX
second point, NO EASY FIX
;D ;D ;D ;D ;D
Ok Ok, back to business, hang on ;D ;D ;D ;D ::)
Ok Ok, I have a some Alloy tanks with lots of bog in them that I want gone(the bog, I want the bog gone, not the tanks ::) ).
Has anyone ever found a painless way of removing the bog without removing or damaging any more of the alloyminium?
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Bogged and painted tank. Needs a repaint now as modern riding pants plus knee braces have made a mess of it, but i don't have to worry about dropping it and stuffing hundreds of $ of repair work
(http://i300.photobucket.com/albums/nn38/mainline_bucket/tank.jpg)
Geez, that turned out allright 8) good on ya!
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I have a some Alloy tanks with lots of bog in them that I want gone(the bog, I want the bog gone, not the tanks ::) ).
Has anyone ever found a painless way of removing the bog without removing or damaging any more of the alloyminium?
Surely some one knows a quick easy way of dissolving or removing bog from an alloy tank without doing anymore damage to the skin?
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Have just read the label on my Septone paint stripper (that softens bog). It says it is made from dichloromethane, phenol and ammonia. No wonder it makes your eyes water
When I was a kid I used methylene chloride to do the same thing
edit no 2
I just read the warning section on the label and on there it says it contains methylene chloride
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Have just read the label on my Septone paint stripper (that softens bog). It says it is made from dichloromethane, phenol and ammonia. No wonder it makes your eyes water
When I was a kid I used methylene chloride to do the same thing
;D ;D
Thanks mate, I appreciate it. It prompts the obvious now, there is a really good auto paint shop here, I will go and see if they sell it, thanks.
This is the tank as purchased
(http://i677.photobucket.com/albums/vv132/mc125mick/20150811_180111_zpsbrhbpsu3.jpg~original)
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I think I bought the paint stripper from Super Cheap or Autobarn
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I think I bought the paint stripper from Super Cheap or Autobarn
Yeap, thanks David I will take the phone with me because I have already forgotten the name of it ;D
I should be able to sharpen up an old plastic tooth brush to then dig it out without gouging the Aluminium.
Then finish with a soda blast I imagine, cheers.
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Careful work with a bench grinder mounted wire wheel will quickly remove bog- at least to the point where the stripper can easily take off the last traces.
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I just use mechanical means to remove the bog, quick and simple.
Wire brush on angle grinder to remove bulk then wire brush on drill or die grinder which will be a bit more gentle when getting closer to the alloy.
Then scotchbrite wheel on bench grinder to finish off and also remove paint if it's not too thick
Use a mask to avoid breathing the dust though
Scotchbrite wheel did most of the work to remove clear coat & stickers on on this job.
Scotchbrite wheels can be a bit expensive though and sharp edges will chew them up quickly
(http://i15.photobucket.com/albums/a393/gmcloa/Repairs/TT%20tank%20002_zpsxjaulqqo.jpg) (http://s15.photobucket.com/user/gmcloa/media/Repairs/TT%20tank%20002_zpsxjaulqqo.jpg.html)
(http://i15.photobucket.com/albums/a393/gmcloa/Repairs/TT%20tank%20013_zps8revw1ap.jpg) (http://s15.photobucket.com/user/gmcloa/media/Repairs/TT%20tank%20013_zps8revw1ap.jpg.html)
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Thanks Momus and Geoff. I appreciate your efforts.
Cheers :)
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Any one have ever used hot air gun/propane torch to strip paint? Painters do that often as far as i know. Heat will not hurt aluminium or steel.
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Heat is not a very successful technique on modern auto finishes as opposed to house paint; you end up with a sticky mess ime.