Cutting metal

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Taywood

I'm about to do surgery on my Kona Lavadome. The seat tube has a single bolt thru two brazedon lugs
and I need to replace this with a new Seat Clamp. I've bought a new rear brake cable guide, new seat
clamp and a shim before I cut metal.

My question to you is How do I cut two brazed lugs off a cromoly seat tube? I've no experience of
this. Should I borrow a dremel tool, a B+D hammer drill or an angle grinder and having severed the
lugs what tool should I use to grind off protruding metal. I'd appreciate any advice.

The new seat clamp is a two bolt deep job to disguise my handiwork. Mike

Tony Raven

In news:beptev$7sgkk$1@ID-131715.news.uni-berlin.de, Taywood <taywood@deadspam.com> typed:
> I'm about to do surgery on my Kona Lavadome. The seat tube has a single bolt thru two brazedon
> lugs and I need to replace this with a new Seat Clamp. I've bought a new rear brake cable guide,
> new seat clamp and a shim before I cut metal.
>
> My question to you is How do I cut two brazed lugs off a cromoly seat tube? I've no experience of
> this. Should I borrow a dremel tool, a B+D hammer drill or an angle grinder and having severed the
> lugs what tool should I use to grind off protruding metal. I'd appreciate any advice.
>
> The new seat clamp is a two bolt deep job to disguise my handiwork.

Why do you want to change from the lugs? Are you really really sure you want to do this?

Tony

--
http://www.raven-family.com (http://www.raven-family.com/)

"All truth goes through three steps: First, it is ridiculed. Second, it is violently opposed.
Finally, it is accepted as self-evident." Arthur Schopenhauer

Jim Price

Tony Raven wrote:
>>My question to you is How do I cut two brazed lugs off a cromoly seat tube? I've no experience of
>>this. Should I borrow a dremel tool, a B+D hammer drill or an angle grinder and having severed the
>>lugs what tool should I use to grind off protruding metal. I'd appreciate any advice.
>>
>>The new seat clamp is a two bolt deep job to disguise my handiwork.
>
> Why do you want to change from the lugs? Are you really really sure you want to do this?

Listen to Tony, think carefully before you abandon any ideas which don't involve major surgery. If
the lugs still work, use them with a new bolt. If they don't (oh no!), then Screwfix do a cheap
angle grinder, but it may be considered sacrilege to take it to a viable and working steel frame.
And if you do, bear in mind that you need to seal the inevitable damage against rust before covering
it with a double bolt seat clamp...

--
Jim Price

http://www.jimprice.dsl.pipex.com (http://www.jimprice.dsl.pipex.com/)

Conscientious objection is hard work in an economic war.

Aye!.

Taywood

"Taywood" <taywood@deadspam.com> wrote in message
news:beptev$7sgkk$1@ID-131715.news.uni-berlin.de...
> I'm about to do surgery on my Kona Lavadome. The seat tube has a single bolt thru two brazedon
> lugs and I need to replace this with a new Seat Clamp. I've bought a new rear brake cable guide,
> new seat clamp and a shim before I cut metal.

There is a rear brake cable guide which takes the cable behind the seat tube and centres it over the
canti cable hanger. Its plastic, its old and weathered and it split. Its held together with
Araldite. I bought the new metal Kona cable guide called a Dog Collar, then found that as its a
solid ring it wont slide down the seat tube because of the lugs. They have to go.

I like canti breaks, I keep them well maintained and cleaned and I have the time to tweak them plus
a boxful of canti brake parts, cables and salmon brake pads which are new or partly used. As this is
probably the last bike I shall own I DO NOT WANT V BRAKES.

Every single shop, stockist or dealer I spoke to or emailed about replacing the cable guide said to
fit V brakes, even Sheldon Brown himself said this. Its new technology to me, its major expense, the
servicing benefits professionals not me, in the same way I dont have Aheadset. Keith Bontrager said
in one of his rants that a well maintained canti is as good as a V brake in all conditions except
for continual hard braking as in the racing scene. So thats the background to the surgery. Mike

Ivor Cave

Taywood wrote:
> professionals not me, in the same way I dont have Aheadset. Keith Bontrager said in one of his
> rants that a well maintained canti is as good as a V brake in all conditions except for continual
> hard braking as in the racing scene. So thats the background to the surgery. Mike
>
>
>
>

If you upgrade you bike to V-Brakes you would know this is not true. After riding a friends bike
that he had put Vees on I upgraded mine the difference is substantial. And in your case could be
cheaper than a new bike if your not experienced with metal cutting tools. One slip and you have a
very weak frame.

Ivor Cave

Tony Raven

In news:ber318$87lqd$1@ID-131715.news.uni-berlin.de, Taywood <taywood@deadspam.com> typed:
>
> There is a rear brake cable guide which takes the cable behind the seat tube and centres it over
> the canti cable hanger. Its plastic, its old and weathered and it split. Its held together with
> Araldite. I bought the new metal Kona cable guide called a Dog Collar, then found that as its a
> solid ring it wont slide down the seat tube because of the lugs. They have to go.
>

You can get hangers that hang off the seat bolt and fit in between the lugs. Understand your wishes
to stick with cantis but what you are proposing to do could leave you with no choice as new frames
are now inevitably v-brakes and that's the way you are probably heading. If you know enough to do
the frame mods competently you wouldn't have needed to ask the question of how to do
it.

Other options:

Get a frame builder to do the mods properly Get a frame builder to braze on a hanger Get a seat
tube clamp adapter for a bolt on front derailler and modify it to act as a cable guide (probably
the easiest and cheapest option) Get a clamp on cable stop from Ison (they open out to go round the
seat post)

Tony

--
http://www.raven-family.com (http://www.raven-family.com/)

"All truth goes through three steps: First, it is ridiculed. Second, it is violently opposed.
Finally, it is accepted as self-evident." Arthur Schopenhauer

W K

"Taywood" <taywood@deadspam.com> wrote in message
news:ber318$87lqd$1@ID-131715.news.uni-berlin.de...

> I like canti breaks, I keep them well maintained and cleaned and I have the time to tweak them
> plus a boxful of canti brake parts,

well, if you like fiddling. ...
> I DO NOT WANT V BRAKES.
...
> Its new technology to me, its major expense,

I haven't got the prices off hand, but what ... 40 quid?

> the servicing benefits
> professionals not me
... Eh? the non-servicing of V-brakes makes them very good for people who are not professionals and
who aren't very good at fiddling or maintenance.

> Keith Bontrager said in one of his rants that a well maintained canti is as good as a V brake

Even if that is true, its only "as good as", and then only if looked after rather well.

I'm not raging against canti's, but V's are good, simple, technology that work - so why butcher
the frame?

Cicero

Mutz

On Sat, 12 Jul 2003 22:09:44 +0100, "Taywood" <taywood@deadspam.com> wrote:

>I'm about to do surgery on my Kona Lavadome.

Forget using an angle grinder unless you have a REALLY REALLY steady hand. One slip and you are
going to make a real mess. If you are still sure you want to remove the lugs then use a hacksaw to
get most of the material off and then use a file and emery cloth to finish off, it'll take longer
but you are not going to graunch a hunk out of your frame in a millisecond like you will with a
grinder. Slow and steady is the way to go.

Eatmorepies

> I like canti breaks, I keep them well maintained and cleaned and I have the time to tweak them
> plus a boxful of canti brake parts, cables and salmon brake pads which are new or partly used. As
> this is probably the last bike I shall own I DO NOT WANT V BRAKES.
>

1. Paying a frame builder to do it will cost loads more than V brakes.
2. If you do do it - use hand tools only. If you're not skilled with a hacksaw, find someone who is.
3. Try V brakes first.

If you live in Mid Wales come to my house. I have some spare V brakes (having gone hydraulic). You
are welcome to try them - I think you will be pleasantly suprised at their power and simplicity.

John

Taywood

Thanks for the responses, some are very helpful and give me lots to think about.

I do not want V brakes, having said that in capital letters to avoid any discussion on the subject,
why have people gone on about it. Perhaps I dont understand people or perhaps I've not expressed
myself clearly.

I've passed on my road bike, I've passed on the Orange dream (with V's, fully sussed) and all the
bits and bobs for those bikes I've collected over the years which might come in sometime!

Much to my wifes delight I only have the one old basic bike now. Sure its got threaded forks but
I've got two suss forks and one Project Two all in good nick. Same with tyres, I'm left with Avocet
wide slicks, Velociraptors and Panaracer Fire Pro's. Next seasons 'must have' forks or tyres with
all their doodahs will most likely be incompatible with this seasons stuff and its my decision to
drop out of this new technology and stick to basics as long as I can. I can still look thru the shop
window at all the shiny new bike parts, as I did years ago when my offroad bike had rod brakes and
balloon tyres and I fancied drop bars and narrow wheels.

Having said I'm old and this will be the last bike I shall own it should be obvious I'm on a pension
and the WK estimate of £40 for basic bike parts is something hard to justify. Even worse when I'd be
wanting 2004XTR with Ti levers or such! So thanks again Mike

Taywood

> On Sat, 12 Jul 2003 22:09:44 +0100, "Taywood" <taywood@deadspam.com> wrote:
>
> >I'm about to do surgery on my Kona Lavadome.

Job now completed, Bill Nickson Cycles at Leyland agreed to do the cutting off the lugs. Thanks for
all your responses, everything went well, ermm almost!

Back home I treated the bare metal then put Hammerite on it. Whilst it dried in the sun I uncoupled
the rear brake, removed the old cable guide and found they had accidentally severed some cable
strands, fortunately I had a new cable in 'the box'.

Fitting the new cable guide needed two alu shims, I accidentally dropped one down the seat tube and
it jammed at the bottom. Off came the cranks and the bottom bracket, I cleared the shim by pushing a
coat hanger up thru the vent hole into the seat tube. Then I noticed the outer ring is worn and the
centre ring is missing one tooth. More expense to come.

Fitting the new seat tube clamp was more difficult than I expected. I never thought the seat tube
upstand would be slightly flared from the top tube junction to the top where the seat post goes in.
I expected it to be a constant diameter and had bought a clamp accordingly. With a bit of shaving
metal and brute force it now fits.

Having got the cranks on I tested the brakes - OK On impulse I tested the gears - it wouldnt jump
to big ring. Off with the cranks again and with just a half turn on the drive side cup, tried
again - OK

Bike reassembled and then tested with a road ride in the sun. As always, nothing is ever
straightforward is it? Thanks again Mike

Dave

"Taywood" <taywood@deadspam.com> wrote in message
news:bf425v$ast4a$2@ID-131715.news.uni-berlin.de...
>
> > On Sat, 12 Jul 2003 22:09:44 +0100, "Taywood" <taywood@deadspam.com> wrote:
> >
> > >I'm about to do surgery on my Kona Lavadome.
>
> Job now completed, Bill Nickson Cycles at Leyland agreed to do the cutting off the lugs. Thanks
> for all your responses, everything went well, ermm almost!
>
> Back home I treated the bare metal then put Hammerite on it. Whilst it dried in the sun I
> uncoupled the rear brake, removed the old cable guide and found they had accidentally severed some
> cable strands, fortunately I had a new cable in 'the box'.
>
> Fitting the new cable guide needed two alu shims, I accidentally dropped one down the seat tube
> and it jammed at the bottom. Off came the cranks and the bottom bracket, I cleared the shim by
> pushing a coat hanger up thru the vent hole into the seat tube. Then I noticed the outer ring is
> worn and the centre ring is missing one tooth. More expense to come.
>
> Fitting the new seat tube clamp was more difficult than I expected. I never thought the seat tube
> upstand would be slightly flared from the top tube junction to the top where the seat post goes
> in. I expected it to be a constant diameter and had bought a clamp accordingly. With a bit of
> shaving metal and brute force it now fits.
>
> Having got the cranks on I tested the brakes - OK On impulse I tested the gears - it wouldnt jump
> to big ring. Off with the cranks again and with just a half turn on the drive side cup, tried
> again - OK
>
>
> Bike reassembled and then tested with a road ride in the sun. As always, nothing is ever
> straightforward is it? Thanks again Mike
>
Yeah, but if it was, how boring would life be ?? <sigh!> Well done sir!! Dave.