Now this is what you call learning.. The best few minutes spend on KZfaq ever.. Respect

After having your videos and alignment methods pointed out to me...by one of my students...I switched to your method! I was aware of using the head tube as the datum, by Jamie Swan and others, but no one ever would show how they would cold set it and that always baffled me...you have to cold set and using the bottom bracket whipping post was the only way I knew or was taught. And yes we [at the factories where I worked] always had the problem of not being able to flip the frame and we had very nice flat surface plates. I think it has to do with squeezing the bottom bracket shell and that gives you a different reading every time you smash it in the BB post. So thank you very much!

Paul should have at least 100k subscribers.

I'm not a frame builder, but a hobby machinist. This just show how much can be done with simple home made tools, instead of running off to buy the most expensive and fancy equipment. Very interesting video, and alignment is useful in many ways. Totally agree on the symmetrical test, by flipping the frame over. It should be the same. Thanks.

Old school frame building, I learnt in the 1970's at the Holdsworth cycle, from British old school frame builders same way you do now, thanks for sharing from the UK

I had a machinist teach me that, you never take your hand off the chuck key when it is in the chuck. NEVER. That is best lesson ever when using any machine that uses a Chuck Key. Thanks for the Video. 😎👍

Another good show about frames Paul, nice. When I bought my first MTB I could not ride and take off my hand it as no balance at all but six months later I saw a TV documentary about different professions that was about a couple of brothers who built bikes and they had done for 70 years the oldest was 92 years old when they did the program and it was 26 years ago, they showed how they built their bikes including how to align their frames. It was easy, they used the window frame and then aimed and bend with an iron bar, they then told that if you did not do it, you could not cycle without hands on the handlebars. When I had seen the documentary, I tore down my mtb and bent it as they had done, it turned out that the frame was anything but straight but 30 minutes later it was and I still have the bike and ride it.

Thanks Paul for sharing your methods. You are like a Shaolin Monk sharing the sacred art with the outside world...Watch your back!

Great masterclass Mr. Brodie!

I'd love to see a video about building that mini alignment table!

This is the best and easy to find cheap tools to use in alignment

Over engineered solution vs old school, tried and true machinist practices based on basic geometric principles. Simpler is always better. Thanks for taking the time to show this.

When I was a student in the machine shop the way the chuck key being left in the chuck was handled was a demonstration by the teacher. Everyone stood to one side. He put the key in and punched the start button with a bit of tubing. The chuck key fetched up in the wall that was some decent distance away with almighty bang. Yes the wall had numerous holes in it! Then we were taken to the office and shown his 'archive' of accidents involving Lathes that he had attended as an OHS inspector over the years. What was seen cannot be unseen. Over the next two years nobody in the class left the chuck in that I ever saw.

I love the Eyecrometer. Hopefully one day mine will be as accurate as Paul's.

Yes yes yes! Great topic. Fork alignment would make just as interesting viewing. Thanks again for these amazing videos

Love seeing the Campy dropout tools in use. Reminds me of my bike shop days 🤠🔥🔨

As stated in the comments, the surface table should be very accurate for flatness, I would suspect the subtle amount that the downtube is off-centre to the BB is the reason for the discrepancy and perhaps the clamp that holds the seat tube doesn't do enough to isolate movement in that area. the theory behind the expensive surface table is sound, what it doesn't allow for is making a "best case" alignment for a frame when there are discrepancies present (which would almost always be the case). Paul's familiarity with his own method and the way it isolates the different steps are what give him confidence in the result.

I got here one year later, but it was still a very impressive video! I don't build bike frames (or repair them), but I have 3 bikes and I'm pretty sure they are not aligned - now I have some input on how to check them. Thanks!

Even better on the second viewing. Thanks again Paul.

Hello Paul your a good man, you answered almost all the comments in this channel, God bless you Paul! Take care!

Thank you so much. This will help preserve the tiny precious bit of sanity I still have.

What an awesome space to take a class. Thanks for the alignment tips. Very helpful.

That was g'damn awesome. I am getting a 73 Atala back from the sandblaster this week. I have a Home Cheapo straightedge, a c- clamp and a tape measure. I will do what I can.

Really interesting video. My thought after watching it was how well does the alignment hold with use? There wasn't a tremendous amount of force needed to tweak things. I saw you answer to a similar question below, and it sounds like alignments hold well with regular use. I like the examples using homemade alignment tools. Thanks for that. Very useful, and shows what a little creativity and knowledge can do.

@paul brodie Hi Paul, a long time ago, I remember watching a motorcycle frame repairer aligning frames virtually exactly the way you do, except that he had a very solidly anchored fixture to attach the bottom bracket to. He aligned by hand, but used much longer bars than you do to give him the leverage to create the force needed. I also saw him demonstrate how much stiffer you can make a frame with the addition of some very simple relatively small gussets. The difference in resistance to twisting force is astonishing. I have another engineering friend here in Melbourne who currently makes motorbike frames, and if they're not aligned when they come off the jig, he either does them by hand with long levers, or uses a very simple hydraulic jack set up to align them. It's great watching you demonstrating these techniques, my oldest son is doing a welding apprenticeship, and wants to start a shop building custom bicycle frames. This will be the first clip I forward to him. I think your channel will be enormously helpful, and of course it's always easier for someone other than 'dad' to teach them.

Thanks Mr. Brodie. You are a true Master Builder.

This was simply delightful to watch! thanks for sharing all that knowledge and experience Paul. It's priceless, really :)

The way you explain and transfer knowledge is absolutely great. Thanks

Thanks so much for making your channel Paul. I've built two fillet brazed frames and I'm soaking up your content like a sponge. Seeing you jump on the front triangle while it's bolted to your jig/plate brings back memories!

"Alignment" has some good music.

Wow ,,, I never knew that this is where Mighty Mitch made his debut . Ive never seen a surface table like that , is it a special one for bike frame building .? good grief , now Im half way through , and have serious doubts that the surface table is even flat , it would do for making gates on or rough welding jobs ,,,, but thats it. made it to the end , your simple hand tools work the best and follow total logic , the only other thing I would have done was put the frame back on the surface table as a known , and see how far out the table actually is. great video , totally enjoyed it , I will never true a bike frame , but so much of this translates into so many other engineering problems ,.. many thanks for showing us this.

You sir is a very good mecanical teatcher☺️☺️☺️👌

Awesome videos, I'm learning a lot. I'm looking to get a 1987 gt performer with the rear tripod bent and a small dent in the down tube. So this is a great help. Thank you.

👏👏👏 i agree 100% with your allignment process. The reason when you clamp the bike to the surface table your assuming that the face of the bottom bracket it in line with the bikes centre line, when in fact most bottom brackets are a pile of cough! So when you flip it over the errors are seen.

Brilliant amount of information thanks again you’re saving me a lot of money and allowed me to go in a different direction 😊👍

Excellent video Paul! Thanks for your time, cheers, Doug

love your videos Paul and this has to be my favorite one yet. I hope you're healing up ok!

Thank you Sir...more of your expertise to share

I am glad I found your videos as a craftsman is always a joy to watch, Watching your other videos it is easy to you have refined your metal working skills to a very high standard. I came up in auto racing and we straightened race car frames with the same principles as you use. Tie one corner down , support it at the point to bend and as many people as needed on the opposite corner to apply the bending force. Multiple tie downs also help if the supply of human counter weight is low

I once injured myself trying to align a frame for a NOLA local frame builder, when I worked at the Bikesmith in NOLA way back in the mid '80s.(my brain forgets his name, he did consultation for NASA in welding technology) Our table used the Campy bb facing inserts to center the bb on the shaft. It had a very stout and heavy picklefork looking tool for prying, but his frames were so stout, I pulled muscles in the ribs, cracked a braze joint, and the stays barely moved. It was a prototype time trial frame with 3 rear stays a side. First thing we did for aligning was chase the bb threads and then face the bb as little as possible to get a full flat surface yet keep the faces where they were supposed to be. When I flipped frames to check, if it wasn't right both sides, the measurements were wrong at the start. I forget the brand table it was, but it was just a small cast iron one that used a machinist indicators. I rarely had issues with it being right when aligned crank side down vs checking it crank side up. That said, road frames were notorious for moving any how . . . try keeping an old Columbus tubed, Motobecane flexi-flyer aligned. Get the head and seat tube at ∟ to the bb and get the axles in place, and first ride, it moves.

Interesting, mesmerizing, and relaxing.

Thank you Paul for your awesome sharing of knowledge !

Excellent video! Thank you for showing both options! Really educational!

Thank you a lot Paul! Your videos are a real pleasure in those strange times.I'm learning some nice tricks, thank you again. If you would make a video on checking a motorcycle frame it would be amazing. Ciao from Filandro!

What a lesson!. Great method, simple and with common tools, great. I will take note

Wow thanks a lot Paul for this video!

You're 100% classy Paul. Thanks again... I always look forward to your videos. How many Campagnolo tools do you have? You should do a video on those tools only! I have a full boxed set of Campy tools that I bought back in the late 90s. I still use them when servicing bicycles today.

Thank you ,, you have educated me . I'm really surprised that the "expensive" table is out of wack ,

My cro-mo frame need a going over to spread the rear drops. Your method # 2 looks just like the equipment I'd be rigging up. Thanks for a perfect demo.

A super lesson for aligning a crooked bicycle frame. Thanks!!!

This was great! thank you, would love to see a fork alignment too

Beautiful well documented , well filmed and great value for the mind and skill . Just mind blowing how clearly and easily you explaind techniques and how easy it looks in your hands. Just wow ,exelent tutorials. that's why I really, really appreciate your videos and advices in them . Please have a huge aplouse from me and I hope you will continue to make me be amassed and overvelmed by your videos. Huge fan. Sincerely from across the ocean. Cheers

thank you for sharing this! i dont have the space for an alignmet table as a hobbyist, but your method should work fine in the tight space i have. and its very impressive how far you have to move a frame to get it to bend permanently

Thank you so much for sharing!

I really really really thank you for your knowledge giving! You are an amazing guy!!! Thanks again!!

I like starting with bottom bracket seems logical

Very good tips. Thanks🚲🚲🚲

excellent ! very well explained.

No micrometers, lasers and granite surface tables? And you call it "fussy alignment"? Nah... ;-) Of course, I'm kidding. Great instructional video - and while nothing "new" (all the info has been "out there" for quite some time already), it still shows the whole process clearly "from the start (BB) to the end" - with all details and practical hints, like "CrMo memory" stuff. As I mentioned before (in my another comment under another video of yours) I"m not a frame builder, although occasionally I do some minor frame repairs (replacing damaged drop-outs, and such), but aligning frames is just part and parcel of "general fixing" of bikes anyway. Now, I just remembered my first frame alignment attempt I did back in '92 or so, while I didn't have much (if any) clue about frame geometry and all - a friend of mine had a cheap steel road bike that "rode like drunk" (in his words). I took a look at it and noticed its wheels were "crossed" (i.e. not parallel), so without much ado (or thinking) I stripped the bike, put the head tube into some fixture, and twisted the frame until wheels were "aligned" (parallel, but I never checked if they were in one plane). Happy and proud of my achievement I began to reassembly the bike, and then half-way I noticed... that NOW the head tube and seat tube were seriously crossed. So much so that you could see it easily with a naked eye (and half drunk)... What the... bike? Nolens volens I "realigned" the frame back, so the head and seat tubes were parallel again, but then I was back to square one with the rear wheel... Sodding bast... erm, "bike", of course - so, what do I do now? Cut the seat stay, or what?! "Exactly so", as it turned out - after closer inspection I found out that bike was poorly welded at the factory - right seat stay was attached to seat tube approx. 10-15 mm lower than the left one... So I took an angle grinder, cut the welds, repositioned the stay and welded it (with MIG, as it was the only thing I had and know how to use back then) back where it was supposed to be. Crude fix, but hey, it worked! Well, at least it made the whole "bike resembling thingy" (it was tad worse than early Norwegian DBS* bikes) act more or less like a normal bike. Rideable it became, that is.... but I digress here ;-) __________ *DBS stands, apparently, for "Den Besten Sykkel", Norwegian for "The Best Bike". Oh, what a joke it is... Those bikes are (or "used to be", at least) a perfect Christmas gift for a very... naughty and recalcitrant kids.

Love it!

wow Paul, thank you!!!!!

Love your videos. I've never built a frame, but do sometimes wonder why some bikes I ride won't go straight with hands off the bars. Awesome

Usted es un gran maestro. Ahora toca conseguir esas herramientas o hacerlas. Gracias por compartir sus conocimientos.

Thank you for this. Tons of great information. I wish I had got out there for a tour when you were running the school. One question: why are you measuring the centre on the downtube? does it not make more sense to just do head tube and seat tube? To me a downtube theoretically could be any weird shape, like a chain or seat stay can be, as long as it holds the head tube it the right place. But maybe I am missing something? Thanks

Thanks for your videos

Great work

using a cast bb shell, if the faces are not equal to the centerline of the bores . the frame will be out, when you fill it. i was by tot by D.S.

Following from Germany Your Channel is fantastic. I learned so much. 😀

haha damn you show how to do things in a simple logical and cost effective way.. i love it.

Ok, you usually show us tools that most can access or afford, that table, amazing and out of reach. This needs to be a resource at every community college, available by the hour for jobs like this!

And... in the "bicycle co-op" end of town, I teach people how to test and correct frame alignment using a string, a pencil and a 5ft x 2in x 4in (1.75m x 50mm x 100mm) board. As accurate as a rider needs, using less floor space.

Very helpful video, Paul. I’ve got a 105 year old motorcycle with a bent frame and I’m trying to work out a method for straightening it. Those old motorcycles are a lot like bicycles, so a lot of your tools and methods will be applicable, at least in principle. Thanks. 😎

Fantastic video 😊

Master Class Frame Tweaking!

Realigned a car frame with a telephone pole a torch, I beam, and come along. SPOT ON !

Paul, simple cure for leaving the key in the chuck; add a spring to the end of the key. By doing so you have to push the key in the square hole and if you release it, it pops out. Safety third ;-) Best, Job

Paul Brodie Bike whisperer thanks

The method that you went through double checks everything. I am not a frame builder but I have straightened a good number of frames. The only frame table that I had available to me warped over time so I would have to flip the frame for each measurement. That is what is going on with the frame table that the University purchased. He is having the table cast and then grinding it without any time to let it settle. It was really suprising to me that the seller of the table didn't understand what you were talking about by flipping the frame. The last frame that I aligned I did on my milling machine.

Nice job! 👏👏👏👏👏

Thank you for your experience ;)

amazing job i have one ,crashed frame and now i know how to fix it, tnx from brazil, although dont have those tools

Just got a chance to watch this video and I'd bet you...a coffee!... that if you had that table surface ground now you'd see a huge difference to the better. No doubt that was an unseasoned casting when they ground it and it warped. A granite AA surface plate would be delightful overkill. Drill it for thread-serts and amaze your friends!

Awesome. That’s finesse 😉👌👌

I have really enjoyed watching your videos Paul. I am subscribing, and thank you for sharing. you might even find a cup of coffee coming your way!

Excelente adiestramiento. Es un genio!!

Thanks for your video.. im planning to build my own frame,😊

Always informative with with amazing snippets... I made my 2 of my frame alignment tools eg: "Brodie Sticks".... simple and effective tools.....a good solid bench and vice needed......now to make a fork stay jig.....and..... ....Hummmm how to do the final head tube seat stay alignment without a flat solid table? Thanks again!

Thank you for the teaching and SHARING! I imported topline Brit bikes from Mercian, Hetchin, Bob Jackson and a few Italian framesets, DaRosa etc when I owned a shop. It was normal to find the alignment off on the well packed frames when they would arrive stateside. Cold setting was D'rigeur. I know your viewers are sharp enough to realize you do NOT use cold setting techniques the same way on aluminum frames. Just on good, faithful steel, Chro-Mo etc.

Amazing Sir

you've just saved me thousands of dollars

So appreciate these videos, this one especially really demystified something that’d been weighing one me as i gear up to build my first steel frame. Cheers!

Awesome video !!! This just goes to show you don’t have to spend a lot of money to do a better tune !!

I enjoyed watching the process and wish some of LBS in my area would adopt a similar process in frame alignment. Very educational, thank-you. On another note, in your opinion would you attempt to straighten out a wrinkle in a steel top tube and down tube due to a head on collision or replace both tubes? This is a vintage bike and would prefer to keep as much original as possible.

The reason that the surface table doesn't produce more accurate results than it does is because using the surface table introduces a change in the frame of reference, thereby introducing error. You base everything on the bottom bracket - as you should - to align all the other parts. But if you bolt a surface table to the underside of a bike frame, you are making the new frame of reference the surface of the table. So now, instead of aligning everything to the bottom bracket, you are now aligning everything to the surface of the table. No matter how perfect the fixture is and the surface of the table is, the act of bolting the bottom bracket to the table will introduce errors between the bottom bracket and the table's surface, and even more error will be introduced by the height measuring tool that sits on the table surface. A surface table is great for jigging together parts into a unique frame so you can initially weld/braze them together, but anything that is as sensitive as a bike frame apparently is to small changes should use the bottom bracket as it's final all-encompassing frame of reference to bend parts to their final shapes/angles, exactly as you have done.

I do want that table!

Good afternoon Paul, very good video exolicating different ways of aligning the frame, could you tell me where I can get a belt sander like the one at the end of the video ??. Thank you very much and greetings.

It's great how you're sharing your knowledge and passing on great skills. Could it be that the dropouts were so far off because you lowered the alignment tool to the headset bar and I didn't see you move it back to frame height (unless done off camera) to line up the dropouts. It's really late here in England, I should get some sleep. Thanks again.

I had a variety of bikes 🏍 through the years but never even considered the frame may have got misaligned...oh foolish me! Thanks Paul! Love your vids...buy you a cup in Craig, Alaska sometime soon perhaps if I can't send it.

Is that the end of the Frame Building 101 Course? Great video as always.

OMG that looks like my dream shop... I really need to find a place in South Central PA that can help me learn a few things and maybe I can build a frame and make my own electric bike. Edit: I remember as a kid helping my friends straighten their bmx frames and used a piece of square tube w/ a threaded hole on all sides on the ends and in the middle so I could use a bolt as the fine adjust... I'd just bolt it to whatever I was trying to straighten and use it as leverage, it also worked like an alignment tool because I could use a bolt as my fine adjustment.