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treatment for inner frame tube (rust converter & caveat wax)

PostPosted: Thu Apr 07, 2016 8:52 am
by Rhinomerc
Hi All

I am thinking of spraying (through an extension tube) some rust converter then caveat wax. dinitrol products came to my attention (RC900 for Rust then the ML wax - there are so many flavor of caveat wax at dinitrol but this seemed the good one).

I haven't found much on this subject on this forum or others (apart from Vespa ones but that is another story - they really rust!).

So is it something you do when restoring a frame? What product do you use?

regards

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Thu Apr 07, 2016 10:09 am
by HxPaul
I dont bother,I figure..............its lasted 50+ years without it,why bother now.

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Thu Apr 07, 2016 10:30 am
by Rhinomerc
Well, there has been known cases

lately a series 1 was reported in Scootering or on FB (can't remember)


and this weel known now
Image

Maybe they last 50 years but had a 55 years life.

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Thu Apr 07, 2016 10:37 am
by citydaz
Personally i wouldnt bother either.
If you get it grit blasted and then acid dipped prior to painting the external surface that should be sufficient.
there will be an amount of surface rust on every frame no matter how carefully you try and get rid of it.
If this surface rust is left alone it will act as a natural barrier to the creation of further rust.

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Thu Apr 07, 2016 6:59 pm
by HxPaul
Rhinomerc wrote:Well, there has been known cases

lately a series 1 was reported in Scootering or on FB (can't remember)


and this weel known now
Image

Maybe they last 50 years but had a 55 years life.

Thats a cut & shut from Vietnam.

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Thu Apr 07, 2016 8:14 pm
by missing lynx
the main thing is to make sure the weep hole isn't blocked you may by putting any treatment in the tube block it thus not allowing water to escape and causing rust to form more easily

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Fri Apr 08, 2016 9:14 am
by Rhinomerc
Yep, not obstructing breathing holes is mandatory. These products are ware repellent and leave a thin layer ; not all of them but if chosen well and not applied like crazy.

And the rust in the middle of the tube is not just a Vietnamese syndrome.

Look this UK one :

Image

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Fri Apr 08, 2016 10:14 am
by HxPaul
Rhinomerc wrote:Yep, not obstructing breathing holes is mandatory. These products are ware repellent and leave a thin layer ; not all of them but if chosen well and not applied like crazy.

And the rust in the middle of the tube is not just a Vietnamese syndrome.

Look this UK one :

Image

No wax oil,or what ever you use in the frame will prevent that,unless its done from new.Just imagine if that poor soul had treated this scooters frame when he re-built it,thinking everything was ok until he rode it and this happened.

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Fri Apr 08, 2016 12:14 pm
by Digger
Is there any evidence that any of these failures were solely due to rust?

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Fri Apr 08, 2016 1:08 pm
by Rhinomerc
Not sure for these two. If I remember well the first one was after a "rally-like" small jump and the second after a speed bump. So the first one was clearly not normal usage while the second one was. However, the first one may have rust from the outside before a dodgy asian restoration. For the other one, apparently it was a regularly used one so I guess the owner would have taken care of the outside.

Nevertheless I saw one in france that was clearly due to heavy rust coming from inside. The tube split while driving and impossible to have fixed like this http://www.scooterotica.co/forum/viewtopic.php?t=19055&p=135681.

In general I think our machine have great iron and they are fine (for many more years at least). Some may have suffered issues in the past (left rusting outside in the wet, deeped in a lake...) and break now. some prevention may not hurt.

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Mon Apr 11, 2016 9:59 pm
by byron
I have seen two Italian GP frames in the last year or so that have looked fine from the outside, but have been thin enough at that lowest point of the tube to easily push a screwdriver right through. clearly rotted from the inside.
one was discovered when the bike was stripped down for respray, the damage was hidden by the stand.
the other frame had been sat in a loft for 25 years.
so definitely worth considering.
and, as said, check drain holes are clear.

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Mon Apr 11, 2016 11:17 pm
by dscscotty
I've snapped one, my pal has and I've seen quite a few recently that have shown fatigue / rot from inside the frame under footboard bridge. The holes in place for water drainage often get block by paint or road grime and go un-noticed. I now check all frame and lube the inside with ACF 50 or on occasion poured oil into frame.
This is a problem that is become more frequent imho.

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Tue Apr 12, 2016 1:45 pm
by Rhinomerc
Hi

After some research, i found what I was looking for : a solvent based one (used by Land Rover rebuilders) and a cavity wax special for old vehicules.

Not that I have been told to never put water based rust converter before wax s it will inject water in the pipe that won't dry before applying the wax. The wax will then enprison the water making more damages...

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Tue Apr 12, 2016 3:06 pm
by dave81
Are the drain holes at the lowest point of the frame ie under the bridge piece or are they all along the underneath of the frame? I have never had a frame stripped down so that I can see underneath it. Do all frames have them or do later ones, as in SIL, which I have, not have them?

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Tue Apr 12, 2016 3:33 pm
by Rhinomerc
On my TV (sandblasted) there are two: one under the rear strut (where the stand) and one below the tool box. Also there is a larger breather udner the petrol tank.

For S2, I haven't checked mine yet.

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Tue Apr 12, 2016 4:34 pm
by dave81
Thanks Rhinomerc. I will check at the weekend when I am allowed my Sunday afternoon scooter session and rideout!

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Tue Apr 12, 2016 4:36 pm
by Rhinomerc
Cool, I see you have family constraints as me :lol:

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Wed Apr 13, 2016 10:47 pm
by xenia1
When i did my TV1 it was first grit blasted then poured hot dilute phosphoric acid into the tube and left it for several hours, once dry used Dinitrol cavity wax.

Re: treatment for inner frame tube (rust converter & caveat

PostPosted: Thu Apr 14, 2016 9:21 am
by Rhinomerc
same product as me.