Dent removal

Pete Beall said:

Rusty has an aluminum bike with a cosmetic dent in the top tube. I
contacted a local auto body shop and they won't touch it. Any suggestions on
who to approach for removal?

My advice: If the tube is straight, leave it alone. If the tube is
bent, get it (or the frame) replaced. Trying to bend that ding back
out will further distort and stress the metal. I've taken dents out
of tubing by ramming a bearing of the appropriate diameter down
through the tube to essentially broach the entire hole, but this is
not a useful technique in your case.

If all you want to do is disguise the ding, swipe a little automotive
scratch filler into it, tape over the area around it with a double
layer of masking tape, block sand it to a reasonable contour *without*
digging into the surrounding paint, and apply touch-up or cover it
with decorative tape or a decal.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Surrealism is a pectinated ranzel.

Pete Beall said:

Rusty has an aluminum bike with a cosmetic dent in the top tube. I
contacted a local auto body shop and they won't touch it. Any suggestions on
who to approach for removal?

Dents are usually just filled before repainting. A framebuilder that
offers resprays can do this for you. I had some horrible chainsuck
scars filled in on my racing bike.

Pete Beall said:

Rusty has an aluminum bike with a cosmetic dent in the top tube. I
contacted a local auto body shop and they won't touch it. Any
suggestions on who to approach for removal?
--
www.petebeall.net

If there is no creasing, you might be able to use dry ice to shrink the
dent back to profile. This works well on aluminum owing to its large
thermal expansion coefficient. It works best when the bike has been in
the sun for a few minutes to get it slightly warm.

Be careful and hold the lump of dry ice with tongs, very thick gloves or
pliers. You need to "melt" the lump to get good contact and to hold it
against the dent rather firmly.

Depending on how much the metal has yielded, you might be able to
completely remove the dent. If the paint has chipped off, results
will be poor.

--

Pete Beall said:

Rusty has an aluminum bike with a cosmetic dent in the top tube. I
contacted a local auto body shop and they won't touch it. Any suggestions on
who to approach for removal?

It's technically different from rolling a steel dent and in
either material you'll lose paint.

A body shop probably wouldn't have the right denting blocks
for that anyway ( you can't get a pick and dolly behind a
top tube dent!)

It won't ever be stronger than it is right now and you could
possibly lose some of an aluminum tube's integrity - got
photos? How deep is it? A sharp-edged dent? From a handlebar
end or from driving into a carport?

--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

Hi Pete,

I am not sure if I have a solution for you. There is a device which welds a
rivit to metal and then use a puller to bring the metal up. I am not sure if
it will work on aluminum. I will give you a link to check it out here
http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=3223
you will need to get some advice. First the paint will have a spot where you
weld the rivit and then you need to paint it again. You'll have to use a
grinder to get the rivit off if it will even weld to aluminum. You might do
well to check with the manufacturer of such a tool to determine if you can
use it on a bicycle tube.
I am handing it off to you - good luck
O' by the way I crashed my bike and my knee put a ding in my top tube and I
left it alone cause the tube appears straight, bike rides straight.
Greg 🙂

"Pete Beall" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Rusty has an aluminum bike with a cosmetic dent in the top tube.

I

Quoted message said:

contacted a local auto body shop and they won't touch it. Any suggestions

on

Quoted message said:

who to approach for removal?
--
www.petebeall.net

Gregory McGuire said:

Hi Pete,

I am not sure if I have a solution for you. There is a device which welds a
rivit to metal and then use a puller to bring the metal up.

Versions of the "rivets" exist for steel and stainless; it is
generally NOT a good idea to try this with aluminum, as it will often
just create a weak spot where the item spot-welds itself down, which
then *rips out* when the tension is applied.

Welding aluminum is best left to those who have the equipment and
skill to do it well.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Surrealism is a pectinated ranzel.

A Muzi <[email hidden]> wrote in message news:<[email hidden]>...

Quoted message said:

Pete Beall said:

Rusty has an aluminum bike with a cosmetic dent in the top tube. I
contacted a local auto body shop and they won't touch it. Any suggestions on
who to approach for removal?

It's technically different from rolling a steel dent and in
either material you'll lose paint.

A body shop probably wouldn't have the right denting blocks
for that anyway ( you can't get a pick and dolly behind a
top tube dent!)

It won't ever be stronger than it is right now and you could
possibly lose some of an aluminum tube's integrity - got
photos? How deep is it? A sharp-edged dent? From a handlebar
end or from driving into a carport?

In a former life, I played trombone. There is a tool used for fixing
dents in brass instruments that is basically a series of balls,
increasing in size, attached to a string. You pick the ball with the
bore that matches the tube, the one that passes through the dented
area, and all the assending sizes in between. You then ram the whole
works through the tube until it passes the bore sized ball freely. It
usually leaves a mark, but this can be buffed out later. I don't know
if there is a simular technique for bike tubes, since they are much
thicker and less plyable than brass and copper, but I would think it
would be possible. The only problem is that you are flexing a piece of
metal over and over, but any repair will do that anyway.

Eric

Quoted message said:

A Muzi <[email hidden]> wrote in message news:<[email hidden]>...

Quoted message said:

Pete Beall said:

Rusty has an aluminum bike with a cosmetic dent in the top tube. I
contacted a local auto body shop and they won't touch it. Any suggestions on
who to approach for removal?

It's technically different from rolling a steel dent and in
either material you'll lose paint.

A body shop probably wouldn't have the right denting blocks
for that anyway ( you can't get a pick and dolly behind a
top tube dent!)

It won't ever be stronger than it is right now and you could
possibly lose some of an aluminum tube's integrity - got
photos? How deep is it? A sharp-edged dent? From a handlebar
end or from driving into a carport?

Eric said:

In a former life, I played trombone. There is a tool used for fixing
dents in brass instruments that is basically a series of balls,
increasing in size, attached to a string. You pick the ball with the
bore that matches the tube, the one that passes through the dented
area, and all the assending sizes in between. You then ram the whole
works through the tube until it passes the bore sized ball freely. It
usually leaves a mark, but this can be buffed out later. I don't know
if there is a simular technique for bike tubes, since they are much
thicker and less plyable than brass and copper, but I would think it
would be possible. The only problem is that you are flexing a piece of
metal over and over, but any repair will do that anyway.

And you get these into a top tube how?

--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

yawl won a free trip to P.R. 3 nights, two days. free booze and girls.
waytogo!