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cutting a head tube by hand?

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Discussion starter · #1 ·
I need to cut a head tube to length but I don't have a lathe.

I need the head tube to have good faces so it will position properly when I place it in my bike stand.

Can I simply rough cut and then clamp the tube in the shop stand and use the the park HTR-1B headset facing tool to face the tube? I think I can get reasonably close with rough cutting and some work with a file.

I know this would be a non-traditional use of the park HTR-1B tool and may mean more cutting wear on the teeth but it would save the cost of buying a lathe in the short term.
 
#4 ·
I cut it as square as I can get it with a hacksaw, and they I go around it with a machinists square (similar to the picture HomeGrownSS linked), and hand file it until it is a close to perfectly square as I can get it. You can get really close by hand, and only have a little taken off after construction when you ream/face it.
 
Discussion starter · #5 ·
Thanks Francis, that was the exact process I was planning. It is good to know that I don't need to buy a lathe for this operation. I plan to buy the ream/face tool and am deciding between the park, strawberry, and other options on the market. I want to have the capability to ream/face without going to the local bike shop each time.
 
#6 ·
It's hard to justify the tooling if you aren't building too many bikes. Eventually it's on my list, as I am a tool junky (as you sound to be), but I can get it faced/reamed for $40 or less at the local shop. Hard to justify $400 in tooling if I build a bike or so a year. There is definitely something to be said for the convenience of owning your own tooling, but don't let "equipment lust" deter you from the goal.
 
#7 ·
If you chucked up a 'squared by hand' ht straight in a 4 jaw and indicated the edge for squareness, you would see that it wouldn't be close to square.. at least not as I define square which is either by proper ht facing with dedicated facer, or much better yet, a lathe. Just sayin.

I've done quite a bit of 'investigation' into this kind of thing. Amazing how unsquare some facers and/or facing techniques can render a headtube. The attitude is (understandably), hey I faced it with fancy tools, gotta be good. With centering cones and facers, I've gotten the best results flipping/facing small amounts repeatedly. Cuts too large, no fluid, not cleaning out chips, old cutters, not removing ht burs, etc etc will all throw accuracy out the window.. kind of alarming once you start digging into it.

Of course at some point, the show must go on, and that beautiful lathe faced ht gets all knackered from welding, and the facing tool becomes the only way to go (facing in the lathe after a frame is done is more for speed.. may be a bit more accurate that a beat old facer, but there's no 4 jaw /single point accuracy involved anymore).

If I was lopping off ht stock in a Park guide, I would invest in one of the little and cheap surface plates, and a good fixed straight edge. Maybe a bit of Dykem to use to spot surface irregularities. A scribe could then be used to scrribe two parallel lines on the ht as guides when starting the process.

-Schmitty-
 
#8 ·
Schmitty said:
With centering cones and facers, I've gotten the best results flipping/facing small amounts repeatedly. Cuts too large, no fluid, not cleaning out chips, old cutters, not removing ht burs, etc etc will all throw accuracy out the window.. kind of alarming once you start digging into it
Click to expand...
Makes a ton of sense. I do this when woodworking all the time but can't think why I never thought to do this on a HT. Great advice.

Now this doesn't make sense to me:

Schmitty said:
facing in the lathe after a frame is done is more for speed..
Click to expand...
Post a picture of that!
 
#10 ·
Schmitty said:
Here you go. That Soulcraft vid has some shots of it too.

-Schmitty-

ps Carl Strong from his web site.
Click to expand...
Gotcha, so the cutter is in the chuck, not the frame? I was envisioning a gap bed lathe with a production frames spinning around at 300 RPM and obviously, that made no sense to me.
 
#14 ·
Good points

But let's not scare anyone. The whole point of facing the head tube is to A) make it fit squarely/straight in the fixture when building the frame, and B) make the headset fit and function correctly. Hand tools (used as described in earlier posts) are adequate for both tasks.

I would also be terrified to put a finished frame in a lathe like that. Sheesh. Hand cutters are not that much work- and if something binds, it's easy to stop. Then again, I imagine Carl knows what he's doing!

-Walt

Schmitty said:
If you chucked up a 'squared by hand' ht straight in a 4 jaw and indicated the edge for squareness, you would see that it wouldn't be close to square.. at least not as I define square which is either by proper ht facing with dedicated facer, or much better yet, a lathe. Just sayin.

I've done quite a bit of 'investigation' into this kind of thing. Amazing how unsquare some facers and/or facing techniques can render a headtube. The attitude is (understandably), hey I faced it with fancy tools, gotta be good. With centering cones and facers, I've gotten the best results flipping/facing small amounts repeatedly. Cuts too large, no fluid, not cleaning out chips, old cutters, not removing ht burs, etc etc will all throw accuracy out the window.. kind of alarming once you start digging into it.

Of course at some point, the show must go on, and that beautiful lathe faced ht gets all knackered from welding, and the facing tool becomes the only way to go (facing in the lathe after a frame is done is more for speed.. may be a bit more accurate that a beat old facer, but there's no 4 jaw /single point accuracy involved anymore).

If I was lopping off ht stock in a Park guide, I would invest in one of the little and cheap surface plates, and a good fixed straight edge. Maybe a bit of Dykem to use to spot surface irregularities. A scribe could then be used to scrribe two parallel lines on the ht as guides when starting the process.

-Schmitty-
Click to expand...
 
#15 ·
It's not scary once you've done it. On Carl's setup, the belt slips on the pulley before it pulls the frame down. Even then, it's hard to get the cutter to bind (read: maybe if you feed a ti frame way too fast, never happened with steel). Once you try it, you wouldn't do it with hand tools again.
 
#16 ·
Alliance Bicycles said:
It's not scary once you've done it. On Carl's setup, the belt slips on the pulley before it pulls the frame down. Even then, it's hard to get the cutter to bind (read: maybe if you feed a ti frame way too fast, never happened with steel). Once you try it, you wouldn't do it with hand tools again.
Click to expand...
Yeah, I used to run some really big taps in the lathe with the tap in the part, the live center in the tailstock in the end of the tap, and a 15" adjustable wrench in one hand and my other hand on the clutch to start it before moving it to the tailstock to keep the tap centered. It wasn't that big of a deal, but I was a lot younger then.
 
#18 ·
How do you guide your HT on the lathe? For the BB, like in Soul Craft video, there is threaded inserts that can be placed to ensure alignment and perpendicularity. How do you ensure that both surfaces are parallel when you flip the frame to face the other side ?
 
#20 ·
jfdupuis said:
How do you guide your HT on the lathe? For the BB, like in Soul Craft video, there is threaded inserts that can be placed to ensure alignment and perpendicularity. How do you ensure that both surfaces are parallel when you flip the frame to face the other side ?
Click to expand...
I've used a bull nose live center a couple of times. It was a bit sketchy, but I made it work ok. I'm considering an expanding internal mandrel mounted to the tailstock.
 
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