Reaming/cleaning seat tube

Alanbt · 02-05-2023 2:47pm #1

Started trying to build up the Colnago steel frame bought recently. Installed the headset and was looking to put seatpost on but it was not not going in more than an inch (careful now…).

27.2 standard seatpost

Emailed the shop and they suggest reaming the tube. Obviously I would have expected this to be done before it left the factory, and I am not doing anything to structurally change the tubing, so am looking to see what homemade tool I can use to see if removing any excess paint or oxidisation from the internal tube will allow me to actually insert the seatpost.

Anyone have any experience or suggestions?

thanks

magicbastarder · 02-05-2023 3:00pm

it's a new frame?

i restored a frame a few years ago. wrapped some sandpaper around an old broom handle (held on with double sided tape) and used that to clean the inside of the seat tube.

07Lapierre · 02-05-2023 3:11pm

Sandpaper and "elbow grease" or alternatively use a power drill and one of these: https://www.amazon.co.uk/Lamellar-Attachment-Cordless-Screwdriver-Straight/dp/B09YR2Q9P3/ref=asc_df_B09YR2Q9P3/?tag=googshopuk-21&linkCode=df0&hvadid=606721237900&hvpos=&hvnetw=g&hvrand=17496769351943060775&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1007850&hvtargid=pla-1678913482959&psc=1

Alanbt · 02-05-2023 3:26pm

It’s a new frame. So it’s something I wouldn’t have expected to need to do at all, but I don’t want to get into returns and disputes if at all possible.

Might try the broom approach first, after I get some fine sandpaper

cletus · 02-05-2023 6:19pm

https://www.boards.ie/discussion/comment/120547081#Comment_120547081

You can get adjustable reamers that will fit in a drill. That would be the ideal route.

Having said that, it's a brand new frame, so I would be returning the frame and asking for it to be done by them/manufacturer under warranty

Alanbt · 02-05-2023 10:41pm

https://www.boards.ie/discussion/comment/120547681#Comment_120547681

I’ll give it a quick DIY effort (nothing hardcore) and if it doesn’t make an obvious difference it will be going back

8valve · 04-05-2023 10:23am

Curveball reply, here....

Is it definitely 27.2mm?

does a 27.0 or 26.8 fit without wobbling around inside the seattube?

magicbastarder · 04-05-2023 10:35am

bike24.com currently list 5 different colnago steel frames - all 27.2mm seat tubes.

Alanbt · 04-05-2023 7:48pm

It’s definitely 27.2. Unless every listing of the frame on the internet is wrong.

picked up a wire brush just now and will give that a go tomorrow and try again.

The shop is still waiting to hear back from Colnago about it.

Guy here have the same issue at same time https://www.lfgss.com/conversations/370177/?offset=300

CramCycle · 05-05-2023 1:26pm

After the light sanding, put in a cloth to see are you getting any rust debris coming out. I'd be more worried if a brand new frame is showing rust spots.

Alanbt · 08-05-2023 2:14pm

The bit of sanding did the trick and able to get the post in fine now. I seem to have lost the BB cups somewhere in the house/shed, and if I don't find them soon this build may have to be put in hiatus due to a non-bike arrival due in 2 weeks.

Hopefully able to get this done in time to actually ride it this summer!

The Ging and I · 08-05-2023 2:21pm

Theres a specific tool for this, its probably paint. I would not recommend a power tool as these tubes are thin enough to begin with.

Alanbt · 08-05-2023 2:33pm

https://www.boards.ie/discussion/comment/120570531#Comment_120570531

A large drill bit with fine sandpaper taped around it. very technical here!

magicbastarder · 08-05-2023 2:42pm

https://www.boards.ie/discussion/comment/120546968#Comment_120546968

just thinking; either myself or cletus, with access to a woodturning and a metal turning lathe respectively, could probably make a range of these tools to suit various diameters of tubing.

artisanal reamers.

Alanbt · 08-05-2023 3:03pm

https://www.boards.ie/discussion/comment/120570659#Comment_120570659

Organic?

cletus · 08-05-2023 3:39pm

https://www.boards.ie/discussion/comment/120570781#Comment_120570781

Yes. Also vegan friendly, and gluten free

cletus · 08-05-2023 4:48pm

For future reference, this is the sort of thing you want. They come in different sizes, the link below is just an example

https://amzn.eu/d/8Tywo9e

sbs2010 · 22-09-2023 11:18am

https://www.boards.ie/discussion/comment/120570502#Comment_120570502

Hi, did you ever get this built up - how did it turn out?

And can I ask- is that a brand new frame or old stock? I have one from 2010 that doesn't have the dimple in the chainstay that gives clearance for the inner chainring. And your cable guides are different too.

The dimple is definitely a good idea, clearance is very tight on mine.