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Discussion Starter · #1 ·
What's everyone's experience with straightness of head tube stock? I can live and deal with main tubes being slightly "banana'd" but I've got a 240mm long 1m thick ht that is so wonky I can't get it indicated in the lathe. Spinning it on the ends in two v blocks and indicating the center, it's >.045" out. Barely rolls across the alignment table. It's pretty thin wall too, so not much chance of the id being straight and just the od wonky.

The ht's I've gotten before are usually pretty damn straight. Bad ht or part of the game that I've been blissfully ignorant about?


-Schmitty-
 

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Discussion Starter · #3 ·
That's what I say.

Just waiting for Walt to chime in and say they are all like that, and It is yet another skill to learn how to use them to make a straight frame!

-Schmitty-
 

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Randomhead
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it probably would work, you're going to face and ream it anyway. I don't think any of the HT stock I have is anywhere near that bad though.
 

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Never seen that...

To be honest, I have never bothered to check a head tube like that. I just chuck 'em up in the lathe, face 'em, and call them good. But I think I would notice .045" out of round while doing the facing, so I'm guessing you've got a bad one. They spin smooth and even (to the eye) in the lathe - I generally use the TT HOXPLATHT2 for 1 1/8".

If you're willing to invest the time to contact them, the distributor/manufacturer will most likely just send you a new one.

-Walt
 

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Discussion Starter · #6 ·
That's my plan...

I use the 4 jaw to face and noticed how wonky it was trying to get it centered, then I threw it on the table to see wtf was going on.

I should just check every tube as soon as I get them. I had one day to get cranking on this frame, and now I'm dead in the water. Oh well.

-Schmitty-
 

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This is why I always use HT made on a CNC machine , you just know their straight and dead to the #'s using a piece O pipe always seemed like the wrong application for this material.
 

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Schmitty said:
That's my plan...

I should just check every tube as soon as I get them. I had one day to get cranking on this frame, and now I'm dead in the water. Oh well.

-Schmitty-
Yes, you should. scrub all the scale, and clean the tubing too - you will be suprised what you will find, and A bad seam on a tube wilI bum you out if you find it after fab is done. bet i know what kind of HT it is. I use True Temper 37mm bought in 5' lengths. always straight, presses cups in nice, cups stay there. good stuff! - Garro.
 

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Eric the Red
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coconinocycles said:
Yes, you should. scrub all the scale, and clean the tubing too - you will be suprised what you will find, and A bad seam on a tube wilI bum you out if you find it after fab is done. bet i know what kind of HT it is. I use True Temper 37mm bought in 5' lengths. always straight, presses cups in nice, cups stay there. good stuff! - Garro.
Is that the MHT from Henry James?
 

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Discussion Starter · #10 ·
coconinocycles said:
Yes, you should. scrub all the scale, and clean the tubing too - you will be suprised what you will find, and A bad seam on a tube wilI bum you out if you find it after fab is done. bet i know what kind of HT it is. I use True Temper 37mm bought in 5' lengths. always straight, presses cups in nice, cups stay there. good stuff! - Garro.
I gots a long list of 'shoulds'!

Another is a build/process checklist including checking the tubes asap.

I'll let fly with the details after I deal with the supplier. Fwiw, I've used the ht before no issues before or after building.

-Schmitty-
 
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