PMW 44mm head tube: overkill for most applications?

[golden boy]

I bought a 44mm Paragon Machine Works head tube, thinking this was a great way to future-proof a mountain bike frame. Then it arrived: Holy Cow! This thing is massive!!!

Is it just me, or does this HT seem like overkill for a typical steel hardtail application? I'd like to hear from others that have used this HT. What was the application? And how was it to weld (or more important to me) fillet braze? It's so massive, it seems like it would be difficult to balance the heat between this head tube and a .8mm top tube/down tube.

[Walt]

They are just a steel clone of the ti head tube (which is itself overbuilt, IMO). Probably almost twice as much material as you need for even a huge, super aggro rider.

The True Temper 44mm head tube stock is a better bet, IMO. 1.25mm wall straightgauge, heat treat 4130. Bomber enough that I'd use it for a DH bike with no hesitation. And 40% lighter.

-Walt

[todwil]

It has a nice finished look to it....a custom look if you will but lots of extra material.
I chose those to help control heat when I thought I going to burn thru the .035 tubing.
The real draw back is .020 undersized that's hell to ream it needs to be like .005!

[golden boy]

Thanks for letting me know I'm not crazy, Walt. I barely even qualify as a beginner, but that tube just seemed ridiculous. I'll look into the TT stock.

And personally, I wouldn't want to use a shaped head tube when the rest of the main triangle is straight cylinders.

[Walt]

That's the part number. Call Henry James up. They may only sell a big long stick of it, though, I'm not sure. If you need just one head tube worth and they can't help, let me know and I'll hook it up for ya.

-Walt

Thanks for letting me know I'm not crazy, Walt. I barely even qualify as a beginner, but that tube just seemed ridiculous. I'll look into the TT stock.

And personally, I wouldn't want to use a shaped head tube when the rest of the main triangle is straight cylinders.

[golden boy]

Thanks, Walt. On their pricelist they list a short (250) and long (1524) version. A short should nicely make 2 head tubes.

[RCP FAB]

Does anyone have any pictures of a headset installed using the TT tube? Do the cups hang over the tube? Thanks

[18bikes]

surely someone must do some reinforcing rings that fit either the TT tube or the Reynolds one?

[RCP FAB]

I'm sure, but at that point might as well just use the Paragon head tube.

[Walt]

I don't have any pictures handy of a full frame but when we got the original tubing made I took one of a bare tube with a King HS:
Waltworks Bicycles: 44mm headtube stock is here!

So that's what it looks like. IMO it looks just fine but I'm on the far end of the function>form spectrum so for those who want a fully flush upper HS cup, it won't be your cup of tea.

-Walt

Does anyone have any pictures of a headset installed using the TT tube? Do the cups hang over the tube? Thanks

[jgerhardt]

They do overhang a little both with the internal headset:

and the external:


Rings would be awesome, and still lighter than the Paragon.

[G-reg]

What's the wall thickness on the TT tubes?

The Paragon's are pretty beefy, but the machined relief inside and out in the middle of the tube doesn't seem excessively thick. The fat ends are nice for reaming/strength/looks.

I'm in for 18's tapered tubes, no worry about overhang with external cups.

[RCP FAB]

TT's is 1.25mm wall

The center of the paragon head tube is 1.3mm

[Meriwether]

I don't think anyone makes cups for the TT stock. I hacked some tube and made my own but it wasn't pretty. May just be superficial but makes me feel better since I did have the reamer make the wall somewhat thinner. If your heat control isn't perfect the Paragon is nice insurance.

[RCP FAB]

It has a nice finished look to it....a custom look if you will but lots of extra material.
I chose those to help control heat when I thought I going to burn thru the .035 tubing.
The real draw back is .020 undersized that's hell to ream it needs to be like .005!

This has been changed, slightly... They are now .010-.020 undersized. I still open them up slightly on the lathe before building the frame.

[golden boy]

Good question about cups hanging over the tube. Thanks for the photos, guys. That is a consideration. The internal cups look rather severe with those sharp edges. The external cups, less so. Easily mitigated with a reinforcing ring, at least.

[e.gellie]

I just used a Phil Wood half-link EBB housing to create a reinforcement ring for a TrueTemper 44mm HT. The shell I.D. is 46.7mm'ish, to the HT's 46.4mm O.D. Not a perfect fit but fill-able with silver-solder. You need a lathe to part it, face it and add a nice chamfer. It beats making one from the Headtube itself.

Ewen

[coconinocycles]

I worry about the downtube punching through if the 44 HT is too thin RE: beer can thoery.
just put some big-ass vent holes in it.
Some mighty leverage on a 520mm+ ATC..........................
- Steve Garro, Coconino Cycles.

[Walt]

I have 250# aggro dudes on the TT head tube with long 29er forks, for multiple years of riding now. You will not beer-can a 1.25mm wall heat treated tube like that, no way no how. In fact I don't think I've ever seen a head tube collapse - I've seen ovalized ones but it seems like you'd have to have multiple other tube failures to get one to buckle. And I would be amazed if you could push a downtube through the head tube no matter *what* you did to the frame.

Heck, I use 1mm wall (OX platinum, of course, so if you distort it you're going to be real unhappy while reaming) for customers in 1 1/8 all the time. I have probably 100 frames out there with the TT 44mm head tube stock, and I'm sure there are thousands and thousands made by other builders. I have never heard of anyone having any problems.

But if the Paragon makes you happier/sleep better at night that is totally worth it.

-Walt

[e.gellie]

Good to hear that info Steve and Walt.
I mostly use 858 or 757 downtubes, so run the TrueTemper HT without a reinforcement ring for those, and add a reinforcement ring for 969 DT's.

Walt, are you using reinforcement rings on those HT's Walt? Is there a source of 1.25mm wall head tube in 44mm?

I'll take back my recommendation of Phil Wood 1/2 link EBB shells for 44mm HT reinforcement rings since three just arrived .... I'm grumpy about a 100% price rise since a year ago without me having being sent an updated pricelist. The webstore doesn't list nearly all of the parts at the moment either.

[Walt]

I do not reinforce them. 1.25 wall x 46.5mm OD is a TON of material. True Temper/Henry James sells it in short (250mm) or long (1M I think?) depending on what you are doing/how many bikes you want to build.

Part "number" is MHT44.

-Walt

[coconinocycles]

But if the Paragon makes you happier/sleep better at night that is totally worth it.

-Walt

It totally does.
All engineering failures ultimately are due to a lack of redundancy.
Just drill big vent holes.
- Steve Garro, Coconino Cycles.

[golden boy]

Steve, do you find it difficult to equalize the heat between that massive head tube and the relatively thin top/down tubes when brazing?

[coconinocycles]

Steve, do you find it difficult to equalize the heat between that massive head tube and the relatively thin top/down tubes when brazing?

No.
Put a thin coat of flux over the HT & turn your torch to 11 and get that ***** hot - get the flux clear - if you don't do this they DISTORT like crazy as well.
- Garro.