Glueing tubulars [the tubular thread]

Everything about building wheels, glueing tubs, etc.
Geoff
Posts: 5137
Joined: Sat Dec 13, 2003 2:25 am
Location: Canada

by Geoff

@3Pio, well, it certainly sounds like you are doing a good job of preparing the rim. Other than the number of layers of glue on the rim and the tire (and where I put the final layer prior to mounting), the only thing I do differently is to wipe the rim with a clean damp rag before starting the glue job. There is no way that is the difference.

It sounds to me like your glue job should be fine. I wonder now if your 'thumb test' is too aggressive, or something. Do this: throw 7 bar in it and let it sit for a couple of days, then check it again. It should be impossible to move that tire by hand.

User avatar
dj97223
Posts: 665
Joined: Sun Nov 06, 2005 7:27 pm

by dj97223

Yeah, I only use the "thumb test" on a mostly deflated tire to look for gaps between base tape and the edge of rim -- I'm not trying to remove the tire. The Park Tool website has an illustration.
“If you save your breath I feel a man like you can manage it. And if you don't manage it, you'll die. Only slowly, very slowly, old friend.”

by Weenie


commendatore
Posts: 181
Joined: Mon Dec 30, 2013 1:51 am

by commendatore

eurperg wrote:Old school yes, but is there anything more beautiful and nicer to ride than a shiny bright Record hubs and Nemesis rims combined with some nice French artisan tubulars? ;)

I won't actually race 'cross, just ride on gravel and muddy farm roads...

Thanks sungod for the tip!


I wouldn't bother with Belgian tape unless you're racing cross. We use the tape to get a better bond because of the higher lateral load on a tire at a (very) low pressure under tight turns. For gravel or farm roads just skip it.

3Pio
Posts: 868
Joined: Wed Mar 09, 2016 7:13 pm

by 3Pio

Geoff wrote:@3Pio, well, it certainly sounds like you are doing a good job of preparing the rim. Other than the number of layers of glue on the rim and the tire (and where I put the final layer prior to mounting), the only thing I do differently is to wipe the rim with a clean damp rag before starting the glue job. There is no way that is the difference.

It sounds to me like your glue job should be fine. I wonder now if your 'thumb test' is too aggressive, or something. Do this: throw 7 bar in it and let it sit for a couple of days, then check it again. It should be impossible to move that tire by hand.


@ Geoff Sungod dj97223

I started to think the same.. That maybe my push test it's too agressive.. Anyway, when i'll trow the 7 bar, and let it sit for few days.. That mean after few days the pressure will be much less, like 2-3 bar.. U suggest to try checking again with low pressure (the pressure ill have after throwing 7 bar and waiting few days), or to throw again 7 bar after few days, and to try that way if something is moving or not. I can do as first just a small push test as soon as i glue the tire plus 24 hours for drying just to find some gaps..

But let's get back few steps in the back.. As u remember i had some base tape ripped off the tire when i removed this tire (i had same problems with two tires actually, (but i think i learned how to remove without ripping the base tape, so hope this wont happened again)).

I got suggestion to glue some base tape from old tire, and using shoe contact cement. I done that using Dunlop Shoe contact cement (could not find Mapei Carpeth cement).

When i removed the tire now, i realized that two patches of base tape i glued with shoe contact cement on the tire (as i said i have another tire like this, also two patches except there the patches are bigger, but for now lets forget that one), almost dont have a glue.. Whole shoe contact cement was left on tire, and those patches was sticked to the rim (so seem that mastik was stronger glue compare to shoe contact cement i used).

Is this safe?

There is the pictures how it look like, and also i made pictures where those base tape patches was glued, and how they look like.. Should i just put them back using the same contact cement or definetely that contact cement is not safe?

About glue on the rim, there was glue leftover, but also few spots without glue. But the glue looked like it's some textile, and not smooth. So i cleaned again (forgot to make a picture before that).

Here is how glue look on the tire after i removed it again..


Image
Image
Image

Image

But for next steps,l i'll definetely put picture on every step to aprove me if its' really ok or not.


First please let's clear those base tape patches. and shoe contact cement...Am i putting them back using the same shoe contact cement, or definetely need to try some other contact cement?

Image
Image

Image
ImageImage

Image


And thanks a lot

sungod
Posts: 1567
Joined: Fri Dec 24, 2010 9:37 pm
Location: it's raining, it must be uk

by sungod

small bits like that i would just glue back with contact cement

as others said above, maybe you are pushing too hard when you 'test'

if the glue is good on the rim, then it is ok, just reglue, mount tyre as you did before, give it a day, ride

i usually take it a little easy the first ride then gently check the glue, after that i am braking hard, cornering hard, so far i'm ok :)

3Pio
Posts: 868
Joined: Wed Mar 09, 2016 7:13 pm

by 3Pio

sungod wrote:small bits like that i would just glue back with contact cement

as others said above, maybe you are pushing too hard when you 'test'

if the glue is good on the rim, then it is ok, just reglue, mount tyre as you did before, give it a day, ride

i usually take it a little easy the first ride then gently check the glue, after that i am braking hard, cornering hard, so far i'm ok :)



I glued those little peaces with shoe contact cement. And as u can see no glue left on them :) So should i use the same shoe cement, or to glue just with Vittoria Mastik ?

And u saw how the tire look like. Should i add thin glue layer all over, or just glue on rim this time and thats it?

sungod
Posts: 1567
Joined: Fri Dec 24, 2010 9:37 pm
Location: it's raining, it must be uk

by sungod

try working the cement into the tape before pressing back onto tyre

i'd pick off any loose lumps. reglue any bare area on tape, then put a coat on the rim and remount

3Pio
Posts: 868
Joined: Wed Mar 09, 2016 7:13 pm

by 3Pio

sungod wrote:try working the cement into the tape before pressing back onto tyre

i'd pick off any loose lumps. reglue any bare area on tape, then put a coat on the rim and remount
.


Thanks for quick reply. Just to be clear..

What u mean by "working the cement into the tape" ? To rub on tape patches and let it dry before getting back? And u mean about shoe contact cement i used, or Vittoria mastik cement?

Geoff
Posts: 5137
Joined: Sat Dec 13, 2003 2:25 am
Location: Canada

by Geoff

With respect to that tire specifically, there does not appear to me that there is any reason to repair any of the basetape. From your initial description, i was under the apparently mistaken impression that a large portion of the basetape had pulled-up. For those minor issues, I wouldn't bother doing anything. I would just apply two layers of glue (keep it thin and even across the basetape) and you should be good-to-go.

That basetape does not look too bad. Ok, there are some blotches, but it does not look like the glue job that it came from is too bad. It does show evidence of a large proportion of the glue remaining on the rim, which is a very good sign.

From everything you are saying and showing, I think your glue job is good.

3Pio
Posts: 868
Joined: Wed Mar 09, 2016 7:13 pm

by 3Pio

Ok, outside it's rainy, and i got a flu (i had idea that riding with 37.2 body temperature will somehow beat the flu :)

And after 90 km with 31 km/h average and 700 meters climb, i feel so good, no evidence of beeing sick after that.

So next day i done recovery ride like 60 km with 24 km/h average and only 300 meters climb, and after that 38 deg for whole day :) Another evidence that recovery ride are not good :)

So as u can see today perfect day for glue job and cleaning my bike.

As i mentioned before, i'll post pics of every step i do now, please be free to comment if im not doing something properly.

I'll try to get as much glue peaces from the tire as possible, and reglue it there. Having dilemma should i put glue just to spots where is missing, or to reglue whole base tape again.

As first i'll post pic of the rim before i start the glue job. I cleaned again with effeto mariposa. This thime i was waiting less time (like 6 hours), and found much easier to clean. Hope this is clean enough for proper glue job after:


Image

Image

Image

Image

Image

sungod
Posts: 1567
Joined: Fri Dec 24, 2010 9:37 pm
Location: it's raining, it must be uk

by sungod

'clean' isn't visible, a rim that looks clean could be oily, a rim that looks dirty could give a strong bond

the thing to be sure of is no grease, oil, or other contamination that might be causing poor adhesion

use clean paper towel and clean solvent to make sure

get the first thin coat on, let it cure, carry on from there

on the tyre, personally i just touch up any bare patches on the basetape

3Pio
Posts: 868
Joined: Wed Mar 09, 2016 7:13 pm

by 3Pio

sungod wrote:'clean' isn't visible, a rim that looks clean could be oily, a rim that looks dirty could give a strong bond

the thing to be sure of is no grease, oil, or other contamination that might be causing poor adhesion

use clean paper towel and clean solvent to make sure

get the first thin coat on, let it cure, carry on from there

on the tyre, personally i just touch up any bare patches on the basetape


Thanks Sungod.

On the rim there is some dryed mix of glue and maripposa cleaner.tried to clean as much with clean cloth and acetone, but there is still left (a little bit).

Not sure how this works for glue job. When is dryed is it neutral and no any other negatie sides for later glue job? Or definetely need to clean everyhing by small detail of maripossa/glue job (not sure if it's maripposa left at all or just glue)

sungod
Posts: 1567
Joined: Fri Dec 24, 2010 9:37 pm
Location: it's raining, it must be uk

by sungod

probably bits of old glue, if they're stuck that firmly they must be good :)

Geoff
Posts: 5137
Joined: Sat Dec 13, 2003 2:25 am
Location: Canada

by Geoff

Wow. You guys sure clean your rims well. I have personally never seen a previously-mounted rim that looks that good. I have definitely never cleaned a rim even a 10th as well as that.

Before you start gluing, maybe wipe the rim with a clean, damp cloth, too. On the basetape, as you know, I prefer to have the last layer on the tire. I would recommend putting a thin, even layer on the basetape just before mounting the tire.

3Pio
Posts: 868
Joined: Wed Mar 09, 2016 7:13 pm

by 3Pio

Geoff wrote:Wow. You guys sure clean your rims well. I have personally never seen a previously-mounted rim that looks that good. I have definitely never cleaned a rim even a 10th as well as that.

Before you start gluing, maybe wipe the rim with a clean, damp cloth, too. On the basetape, as you know, I prefer to have the last layer on the tire. I would recommend putting a thin, even layer on the basetape just before mounting the tire.


About cleaning the rim, it's not that hard with Corogna Remover. Just need to wait proper time, then get some tire levers and get the glue off.

Then wipe with clothes and acetone, and thats it. I needed like between 30-60 min (with drinking my beer while doing that :) )

I just finished the first layer on the rim. Before proceeding cleaned again with acetone and clean cloth. After that i waited a little bit to be dry.

About tire, i found out that there is like small dust from the glue, so i pill off everything i could, and after that washed the whole tire with water.

Now i put them both to be dry.

I wonder why do u prefer putting last layer on the tire and not on the rim? That mean u put two layers on the rim, and on the tire One + Final layer? (so two on the tire)

by Weenie


Post Reply
  • Similar Topics
    Replies
    Views
    Last post