All this talk about jigs reminds me of my grandmother's saying everytime we rolled into the driveway after a trip. "Home again, home again, jiggity jig"
A Zombie Reborn - the build thread
- Thread starter SkyknightJohn
- Start date
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Mostly done with this happy dance, er, jig.
The top tube distance and BB to dropouts are not right in this pic, but you can get the idea. Stll the axle dropout spots to shave off the threads to proper fit, those handles to shorten, though everything else being M8 button heads or socket heads, not sure it’s necessary. Will only adjust it once per frame.
Laser checking the alignment. It is a futuristic post-apocalyptic zombie bike after all
The top tube distance and BB to dropouts are not right in this pic, but you can get the idea. Stll the axle dropout spots to shave off the threads to proper fit, those handles to shorten, though everything else being M8 button heads or socket heads, not sure it’s necessary. Will only adjust it once per frame.
Laser checking the alignment. It is a futuristic post-apocalyptic zombie bike after all
All right all right, getting closer to throwing some sparks! 
Setting distances and sanity checking:
(tubes are just roughly in place)
I realize the instructable suggested 51” horizontal beams, and either through metric conversion or wanting to save on shipping, mine are 48”. Still works for the 48” wheelbase with the steep HT angle and the fork offset. Pretty much the limit though.
Noticed looking at the pics that I have the headtube set up to have the front axle in line with the BB, not the rear axle. Easy fix.
Thinking it’ll work out.
Setting distances and sanity checking:
(tubes are just roughly in place)
I realize the instructable suggested 51” horizontal beams, and either through metric conversion or wanting to save on shipping, mine are 48”. Still works for the 48” wheelbase with the steep HT angle and the fork offset. Pretty much the limit though.
Noticed looking at the pics that I have the headtube set up to have the front axle in line with the BB, not the rear axle. Easy fix.
Thinking it’ll work out.
IT’S VERTICAL!
Added the crossbar for mounting the jig to a bike stand. As the instructable says, the CG is too far in front of the bar, no matter how up/down you adjust it, for the frame jig to not want to tip, top forward.
For this pic tightening the clamp was ok, but a support of some sort needs sorted out.
Yes, the angles are off. I had to take a horizontal beam off to insert the nuts for the crossbar. Obviously something did not get back to the proper place. All will be re- re- re- measured prior to any cutting or welding. Still a few bits of prep to go.
Added the crossbar for mounting the jig to a bike stand. As the instructable says, the CG is too far in front of the bar, no matter how up/down you adjust it, for the frame jig to not want to tip, top forward.
For this pic tightening the clamp was ok, but a support of some sort needs sorted out.
Yes, the angles are off. I had to take a horizontal beam off to insert the nuts for the crossbar. Obviously something did not get back to the proper place. All will be re- re- re- measured prior to any cutting or welding. Still a few bits of prep to go.
Awesome! I wonder (no worries though!) how stiff the complete setup is. Extruded aluminum can be quite stiff, especially with the open ends shut.
Can't wait for the next chapter in the build process!
Can't wait for the next chapter in the build process!
It’s pretty stiff. Some of the more professional builders use similar setups, usually more like the Arctos design. Even some pro-grade for sale jigs use extrusions as their frame.
Pithy Bikes on youtube has a wonderful series of his process making an Arctos clone, as well as bike builds, low budget wooden jig build, and others. Quite good viewing.
With the nature of the T-nuts there is some possible slop in alignments I’ll watch out for. Not sure how stable the bike stand mounting will be until I figure out the tendancy for rotation. May come up with another plan for a stand.
I have some concerns that the axle and BB rods may droop. Seem fine for now with 20mm thread depth plus a nut at the base to lock it in. Will have to see, and I have contingency plans.
Within the jig I think the tubes will be held fine. Better than any previous set up I’ve had. Not going for race-bike precision… This is Rat Rod Bikes.
Pithy Bikes on youtube has a wonderful series of his process making an Arctos clone, as well as bike builds, low budget wooden jig build, and others. Quite good viewing.
With the nature of the T-nuts there is some possible slop in alignments I’ll watch out for. Not sure how stable the bike stand mounting will be until I figure out the tendancy for rotation. May come up with another plan for a stand.
I have some concerns that the axle and BB rods may droop. Seem fine for now with 20mm thread depth plus a nut at the base to lock it in. Will have to see, and I have contingency plans.
Within the jig I think the tubes will be held fine. Better than any previous set up I’ve had. Not going for race-bike precision… This is Rat Rod Bikes.
The old one we had for our flat track frames had cheap digital angle finders ($15 ea Amazon) mounted onto the brackets. Set it all up, zero those gauges, then it's just checking them for zero pre and post weld. I could definitely see some movement in the T nuts as you described
We used to see some +/- 0.5 in the head tube but those are much thicker tubes with more heat
Seat tube cut.
Note my high-tech frame jig stabilization device between the bike stand upright and the bottom jig rail.
Note my high-tech frame jig stabilization device between the bike stand upright and the bottom jig rail.
Laser checking the alignment. It is a futuristic post-apocalyptic zombie bike after all
LASER BEAMS!!!
I’m Daying,
one Cope at a time.
one Cope at a time.
Been a while since I peeked in on your progress, John. Really like the shape of your frame! And typically, the seat tube angle is slacker than the head tube angle, I don't know if I caught what yours were or not?
From the last photos, it looks like you are 'coping pretty well' with these latest developments.
From the last photos, it looks like you are 'coping pretty well' with these latest developments.
Going to be 28* on both. Last frame I had this fork on was 27* and that worked out well. Was considering 30* but the way the stops worked out limited it. Just took the lazy route and said good enough.
I’ve compared all the geometries to my other bikes (reach, seat ht, etc) and think it will fit me well. Really won’t know until it rolls.
Spent a few days at the beach to make this vacation seem like a real vacation. Back to work this afternoon, or tomorrow, or the weekend.
I’ve compared all the geometries to my other bikes (reach, seat ht, etc) and think it will fit me well. Really won’t know until it rolls.
Spent a few days at the beach to make this vacation seem like a real vacation. Back to work this afternoon, or tomorrow, or the weekend.
Downtube mitered. Probably will do some fine-filing for fit yet, but it’s within reason.
You ever do something stupid, and have to go back and re-do most all the work you’ve done? I have.
Bad math, or reading my scratched up plastic protractor, or getting old eyesight…
Well, I bought me one of them fancy new-fangled digital angel finders (they’re in heaven, btw,) and also an angle finder, only to find the angles I thought were 28 were actuall 17.
Long way from the stabe cruiser I’m looking for.
Took the whole jig apart, drilled more holes, made the top beam adjustable vertically, reset all the parameters, now with a proper head tube angle.
Had hoped to do a step or two forward, rather than two back, but alas…
No pics.
Attended a wedding this evening though. Good times celebrating love and friendship.
Bad math, or reading my scratched up plastic protractor, or getting old eyesight…
Well, I bought me one of them fancy new-fangled digital angel finders (they’re in heaven, btw,) and also an angle finder, only to find the angles I thought were 28 were actuall 17.
Long way from the stabe cruiser I’m looking for.
Took the whole jig apart, drilled more holes, made the top beam adjustable vertically, reset all the parameters, now with a proper head tube angle.
Had hoped to do a step or two forward, rather than two back, but alas…
No pics.
Attended a wedding this evening though. Good times celebrating love and friendship.
OK. Last day of vacation, so I had to make up for my setback. Front frame tubes are all re-cut, re-mitered, and ready to be cleaned and tacked.
Back to work tomorrow (Happy Independence Day!
) then some days off before the next trip & more progress.
Back to work tomorrow (Happy Independence Day!
) then some days off before the next trip & more progress.
At least you caught it before it became a more 'permanent' error. I like the new look of the angles, looks more relaxed like a cruiser should.
Looking forward to more progress on this !
Looking forward to more progress on this !
MEEEE TOOO! Sometimes I gotta wonder about the way my brain works. Probably doesn't help dealing with the heat. The garage is better with the insulation and wall board, but still not always sweat-free. Home for the weekend, so hopefully some progress, but have some life events pushing toward the front of the priority list, so we'll see.
All tacked up!
Still near 100 with all the humidity, so that’s enough for today. Tomorrow is supposed to be cooler, so after the yard work and other requisite things, I hope to have time to close up the welds.
Then just build the rear triangle.
Then I’ll be at the “I have a frame” starting point!
OOPS.
Most of the front frame is welded. Started with some practice pieces, then to the front ‘triangle’ to get in the welding groove with the thicker steel…
Not a stack of dimes to be found, but solid and secure welds nonetheless. And, for whatever it says about my skills- I’m pretty good at filling pin holes.
Did ok with some of the seat tube, but this section is obviously a bust. Looked good while welding, but hood up and … NOPE. Don’t know what I thought I was seeing.
I have a spare seat tube, but will have to see how crazy the other tubes move when cut free. Would not like to start over, but has been good welding practice, and given reason to get the Argon refilled and the tools out.
Also, I have a frame jig that will serve well into the future.
Will update when I figure out the next step.
Most of the front frame is welded. Started with some practice pieces, then to the front ‘triangle’ to get in the welding groove with the thicker steel…
Not a stack of dimes to be found, but solid and secure welds nonetheless. And, for whatever it says about my skills- I’m pretty good at filling pin holes.
Did ok with some of the seat tube, but this section is obviously a bust. Looked good while welding, but hood up and … NOPE. Don’t know what I thought I was seeing.
I have a spare seat tube, but will have to see how crazy the other tubes move when cut free. Would not like to start over, but has been good welding practice, and given reason to get the Argon refilled and the tools out.
Also, I have a frame jig that will serve well into the future.
Will update when I figure out the next step.
