How to fix a dent in your bike frame - Framebuilding 101 with Paul Brodie

How do you make a top tube round again? Paul Brodie shares some tricks of the trade 🤓🏁
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#dent #metal #custom #fussyframebuilder

[@pashakdescilly7517]

Many years ago, I was given a classic frame (a 1948 or '49 Duckett) with hand cut lugs - and the down-tube had a deep crush in it, to half way through the tube. I took it to an old-time frame builder, and asked him if he could save the frame. When I went back a week later, he had used blocks just like yours to ease the dent out. He was left with a shallow dent the size of a pea, and he filled it with braze. Just as you did. I am well pleased with the repair.

[@paulbrodie]

Thanks for commenting.

[@azizuladnan2389]

That this frame was repaired by Paul Brodie substantially increased its value.

[@paulbrodie]

You're so funny!

[@weedmanwestvancouverbc9266]

@@paulbrodie Double from $50 to $100

[@sebastienbgagnon8801]

@@weedmanwestvancouverbc9266 Add a 0.

[@boma7437]

I really enjoy your videos, Paul. The content is always highly interesting and well cut. Thank you for sharing your Knowledge with us.

[@SomeTechGuy666]

Mind blown ! How did I not find this channel until now ? Subscribed.

[@Fra123]

I’m impressed so much work to fix a dent! Well done

[@paulbrodie]

Thanks Francesco. Yes, building and repairing frames can be a Lot of work....

[@4G42010]

Thanks a lot Paul for generously sharing your knowledge. Only great people do that!

[@paulbrodie]

Thank you very much. I do enjoy sharing knowledge...

[@lysdexsick]

This is called, being a professional and knowledge throughout years of experience!!!

[@mrexon]

You just got a sub because you proved to me I was wrong about dented frames! Thank you

[@shannons1886]

First time one of your videos was suggested to me. Viewed and subbed. When your video views are that much greater than your subscribers, then you know your channel will grow quickly.

[@MrTiles]

You, sir, are a real pro. Thanks for sharing your time-tested knowledge with us neophytes.

[@paulbuckles5353]

A wealth of information - I'd heard about the wood block method from a friend who wrenched for the USSR team in the mid 80's, but never seen it in practice.

[@dubmfg]

I look forward to watching these every week, thank you Paul!!!

[@weldmachine]

Not disappointed. But i was hoping to see the dent come out of the frame. Glad to know this is how i would do the same repair. Thought there might be something new to learn, LOL. Thanks for bring us along. Peter.

[@Tom-sp2xs]

Already thought you are a Super Man, seeing you file convinced me. Great Videos

[@dariorodriguez7157]

Thanks a lot Paul...I learn a lot from you. From Buenos Aires, Argentina. Thanks.

[@paulbrodie]

Dario, thanks for watching from Argentina!

[@davidbraxton5110]

Excellent craftsmanship, Thank you.

[@paulbrodie]

Thank you David.

[@johnpartridge7623]

You have an easy teaching style Paul, thanks for the lesson 👍

[@paulbrodie]

John, thanks for watching and commenting.

[@kenmcdonald7793]

Thought there where kids having fun in the background... they sound alot like Peacocks. Well, there they were in the backyard of your place. Thanks for the video.

[@anderssoderlind90]

Yes! now I can repair my kona frame and use it again, every one thought I should scrap that frame. Once I was working in my uncles metal shop and learn almost everything how to work with metal. And I have learned something new today.

[@saleemcarr9501]

Dont , your kona will still be a deathtrap just with a plug covering the damage. This isnt a structural repair only cosmetic.

[@aryanraina1076]

i spoke to a framebuilder about the same thing and he said it'd be ok but will reduce strength of the steel in the area. He told me it's better to keep a dent on it for strength. Small dents are okay in low stress areas of the frame apparently.

[@ScrapWolf]

Thanks for this video. Learned a lot!

[@wtfftw24]

Always great handcrafting!👍👍

[@james.d.8044]

Such an awesome video, great channel that's a very cool trick to do with the wood blocks 😀 👌

[@MADTherapist]

Thank you for making this video and explaining it clearly, i have recently decided to build a couple of old bmx gems I've been holding onto for some time. One is a Redline RA340 and the other a dented up 99' Dave Mirra Haro. I will definitely use your method to knocking down a couple of those dents, I was starting to wonder if it would ever happen now I can get it prepared and ready to have it chrome dipped. Thanks and regards, Mike D.👍🏼

[@paulbrodie]

Mike, thanks for watching. Now you can fix those dented BMX frames. Hope you have success!

[@29roadie17]

Excellent! Thanks for sharing.

[@blockhead3654]

Great work Mitch.

[@petermarshall7775]

I am an addict to your shows. The idea of frame building is beyond the capabilities of my eyesight. An old man can dream :).

[@paulbrodie]

My oldest student in Framebuilding 101 was 75; his eyesight wasn't so great and his hands shook but he still finished his frame. Never give up!!

[@phaedrussmith1949]

Bifocals.

[@lihtan]

Good job! It's nice to see you do some woodworking too!

[@lukadude7335]

love it! The tip for handling for low temp intake was really helpful!

[@mrmyorky5634]

I'm probably showing my age here, but many years ago a frame builder that I used replaced my entire top tube rather than attempt to repair a dent. He carefully sawed off the tube about 1/8" away from where it joined the seat tube and the same at the headstock end. He then filed away the remaining bits smooth before putting on a jig and brazing in a complete new tube. The frame was of course fillet brazed originally and although the repair and a respray cost me about half the cost of a new one I was very pleased with the finished result. The frame was built in Reynolds 531 butted tubing and I remember him saying that the heat of the brazing would always cause a slight loss of tube strength locally but because this was at a joint with another tube it was no detriment.

[@paulbrodie]

You are not showing your age. Replacing a tube (done properly) is perfectly acceptable. Repairing a dent is less labour and therefore less expensive. Thanks for watching and commenting!

[@rodrigozepeda3525]

super good video, thanks for sharing !

[@paulbrodie]

Rodrigo, thanks for watching!

[@DavidRodriguez-eh8yd]

Cool stuff, amazing workshop having the right tools to create sky’s the limit

[@paulbrodie]

David, thanks for watching 😉

[@janetmanzoblaz577]

Good work mr Paul newman !!!

[@paulbrodie]

Interestingly, Paul Newman and I have birthdays on the same day January 26.

[@johnnydeutschemark3620]

Loved that fix. I have a dented frame, also on the top-tube and my local frame builder said, "Leave it." The tube is very thin and he felt like it might crack if it was forced 'back to round' or maybe he was just busy as hell and didn't want to get involved. So it remains...

[@paulbrodie]

Yes, you do have to be careful with thin tubes. I would roll it round, and fill any low spot with a little bondo, then repaint. This is safer than using heat and braze on thin tubes.

[@Xavier_Ns]

Dude your so smart this is very useful

[@paulbrodie]

I've been around for a while and I have some experience. Thanks for watching!

[@mymailforplaystore5496]

Ingenious, amazing work...

[@paulbrodie]

Thank you kindly.

[@mtnbikeman85]

Hey, just found your channel. I rented a Brodie once on a trip to Sedona Arizona years ago, would have been 1999ish, I still remember it, a blue hardtail with a white logo and marzocchi bomber. It rode mint.

[@paulbrodie]

And now, apparently, they have become collectible :)

[@mtnbikeman85]

I'd probably buy one to keep if I saw it for sale....don't think too many made it to New Zealand where I live now. PS once this pandemic is over you should do a crossover episode with Allen Millyard.

[@paulbrodie]

@@mtnbikeman85 Allen is about 8000 mies away, but I would definitely sit down and have a cup of tea with him :)

[@jayvee2081]

Such an amazing job 👏🏽

[@spongesurf12]

3:45 Peacocks! Interesting video. Always thought the Brodie bikes were sweet.

[@germancarfan]

Great work

[@antn8387]

absolute legend

[@sidmarlin6497]

Beautiful shop!

[@wrknclass1]

Gangster! Thanks for your time!

[@DJFalkoHannover]

Excellent video! Great relaxxed teaching and explanations. I love to learn all about that stuff. All the best, Paul! Cheers from Germany

[@paulbrodie]

Thank you, thank you everyone!

[@petermoller6345]

@@paulbrodie so ein Käse

[@vanislandsteve]

Very nice work 👍🏻🇨🇦

[@ratheskin58]

At last! Some competition for the calls of the peacocks!

[@paulbrodie]

Peacocks are only noisy during mating season.

[@SomeTechGuy666]

I like the bike stand he uses. My consumer grade POS wobbles every time you touch the bike. His is rock solid. A poor carpenter blames his tools. A great carpenter always has great tools. Lesson learned.

[@allcapitols1554]

I meant to ad that that dent looks like a garage-dent, not something that was a ride gone bad. They're harder to fix than when a handlebar swings around.

[@petermarshall7775]

Wow long time no-see, hope you are doing well in this COVID-19 situation. We are very envious of your workshop here in Havana

[@paulbrodie]

Hi Peter! I do remember you! Hope you are doing well :)

[@stanciualexandru3382]

Mr .Paul you is good work super video Thank for the video

[@paulbrodie]

You are welcome. Thanks for watching!

[@tarabario]

love you, man

[@paulbrodie]

You are very kind.. Thank you!

[@michaelmeakin9674]

Cool! I just stumbled across you video. I have know your name for a long time. When I was a kid I worked for Norman Hill Bicycles at the time Derik Bailey was building frames him. I eventually went on to become a machinist. I still have my early nineties Rocky Mountain Blizzard. I wonder if you made that one.

[@paulbrodie]

No, I only worked at Rocky from 84 to 86. Sorry!

[@hasletjoe5984]

Paul, love the videos as I am a hobby machinist and motorcycle fixer upper wanna be! Curious, when you adjusted the boring head the .076, does the boring head work similar to the lathe and half the amount dialed in? On a side note, one of my friends (who suggested your channel) just pulled the trigger on a Triumph cub! Yep, he went off the deep end for sure!!!!

[@paulbrodie]

Thank you Haslet Joe. On my boring head, when I dial in .050", it takes off .050". Not similar to a lathe. Your friend must be little crazy to buy Cub! At least there are Cub videos he can watch if he needs some inspiration :)

[@pedrojosemorenoferrer2836]

I have quite a larger an spreaded dent in an aluminium frame, is this method suitable?

[@danskustomairbrushin]

solid work ,enjoy the channel. id be interested to know if any pdr (paintless dent repair) techs have had any sucsess in doing a pdr on a dent like this. i did paint for a few local fame builders and a few large bike manufactures and have alot of experance working on this stuff but the idea of pdr a bike never crossed my mind untell watching this for some reason. if anyone reading this knows of someone who has let me know.

[@paulbrodie]

I do not have any experience with pdr, sorry.

[@theoriginalmungaman]

Assuming the frame is steel, you could use an auto body stud welder and weld a stud to the low spot then heat around the dent then pull it with the slide hammer.

[@paulbrodie]

Yes the frame is steel, but often the wall thickness is only 0.5mm and sometimes it is heat treated 4130 so that is not a very good solution, sorry.

[@meboyotube]

I'm going to make a frame clamp just to enjoy that lovely sound it makes. Lol. 🙂

[@paulbrodie]

I'm told that my frame blocks are made from Eastern Maple. Any good hardwood will probably be just fine.

[@lukealexander3639]

I just purchased a vanni losa frameset, has a very minor dent on the top tube, might have to try filling it with braze. Too bad i cant save the paintwork, in the end im a good painter so i should be able to recreate the finish. The finish is a white pearl base with candy red transitioning to orange, yellow till it reaches the seat tube.

[@paulbrodie]

Bondo is another way of repairing a dent, and there will be less paint lost with no heat. Sounds like a sophisticated paint job. Good luck!

[@tongalizia3175]

Greetings mr Paul….. I have an aluminum Bottecchia road bike that has a dent on the down tube by the bottom bracket,,,, does this method work on aluminium,,,, once again great video you and mr Mitch….

[@paulbrodie]

Tony, it might work. But, I have almost zero experience with aluminum bicycle frames, so, if you do try, be very careful!!

[@teunluijbregts2533]

OMG - you've got a Whippet safety? Beautiful machine 😍.

[@paulbrodie]

Built the Whippet in 2012

[@yurib5089]

I like mitch, because he said you needed to do the little dent as well. I like how he kept detail & principles to your work.

[@paulbrodie]

Mitch is a good guy.

[@621ELECTRONICS]

I've used regular plumbing solder / flux and a propane torch to fill some dents. Easy to file / sand to shape, and couldn't even tell it was dented. Not that it is better than real brazing, just an easier solution with very basic relatively cheap tools and what I had on hand. I did try a stud welder (welds the little pins on) and a slide hammer as I see mentioned in the comments, however, I couldn't get enough force to even budge the dent before the pins snapped (the dent wasn't even as bad the one one in the video here). Perhaps there are stronger pins available, never looked into it, was my dads stud welder from when he did autobody repair. I still have it and have another dented frame, perhaps I'll look into it again sometime. I'll say it was a cheaper BMX frame, chromoly tubing, so not sure the wall thickness compared to road / mountain bike frames, so I suppose results may vary with the stud welder. At any rate, nice video, makes me feel a little better about filling the dent on my frame, felt a bit guilty "hiding" the damage (I still own the frame, so not like I did it to sell, just to make it look better).

[@paulbrodie]

Yes, the autobody folks often use lead to fill low spots or dents on restorations. It is a perfectly valid way of doing things. There's always more than one way to do things. Thanks for watching!

[@ppereztaylor]

Paul, I quite enjoy your videos. I have a question for you. I am restoring an old Norco Sports; it is a late 70's or early 80s japanese made frame. The seat stays were bent to the point where they were almost touching. I ended up using a rebar bending bar, but stopped because I noticed I put a couple dents in the seat stay tubes. How would you recommend I try to bend the stays so that they go back to being straight. Do you know if frame blocks are commercially available? Pedro (Edmonton Alberta)

[@paulbrodie]

Pedro, I would have to see the frame. I cannot offer an opinion otherwise, sorry.

[@ronmatthews1738]

I have watched videos about an induction dent removal system for car bodywork and I wondered whether this would work on bicycle frame tubes.

[@paulbrodie]

Car bodies and bicycle frames might be a little like apples and oranges...

[@JulianMakes]

Great video Paul thank you. Can I ask roughly what thickness of cardboard you use when you double it up in the mill? It looks like dense thin cardboard rather than the Amazon box stuff? Thanks!

[@paulbrodie]

Thank you. I'm not in my shop to measure, but it's a dense file folder, maybe .030" thick. Best guess.

[@nickfrost7136]

Thanks for making this. It is very timely for me. I made a lugged frame and used thin tubing for the top tube. Tange Prestige 7/4/7 in 31.8 I crashed yesterday and put a nice big dent in the top tube. I got most of the dent out with a tube block and I was planning to use cycle design system 48 silver brazing rod (what I have) to fill the remaining dimple since the tube is heat treated. Do you think that is this acceptable for heat treated tubing?

[@paulbrodie]

Yes, you just have to be careful. The silver will melt at a lower temperature than bronze which will be good for your thin walled tube :)

[@norberthofer5830]

@@paulbrodie What if you use auto body shop lead, bondo or an epoxy filler to level out the dent. Once you have a majority of the dent out, you are cleaning up the cometics I assume.

[@paulbrodie]

@@norberthofer5830 Yes, those are all good suggestions. I would choose bond over lead, it's much lighter!

[@norberthofer5830]

@@paulbrodie Thank you for response.

[@seanwilliams5053]

Hello Mr. Brodie! I have a question - I have a Salsa Moto Rapido with a dent under the down tube. Since it's an aluminum/scandium alloy, is there anything I can do to repair or reinforce it? Any feedback is appreciated. Thank you, and fantastic channel!

[@paulbrodie]

Hi Sean. Thanks for liking our channel! I have never worked with aluminum/scandium, so cannot say. If the dent has no sharp edges that might develop into a stress riser, I would just leave it.

[@aaron___6014]

Nevermind, I see you have a dent video. Does filling the dent add strength or is it for looks? Thanks

[@rbelang8331]

I wonder if you could use «lead» like the old school body guys use, instead of bronze. That process is used to weld 20 gage sheet metal without putting that much heat... Since the bronze here is only used as a filler...

[@moon-unitwoof670]

What's the functional difference between the aluminium and wooden tubing blocks? Could you hold tubes in the mill for cutting using wooden ones? What are the advantages of the metal ones? The machined alu tubing blocks arlways seemto be machine to hightolerance. Does the parallelism of the sides actually matter when building a bike frame?

[@paulbrodie]

They can both work well. Wood is better for a bench vice, and aluminum in the mill vice. They can both be parallel if they are made well and not abused.

[@andrewut7ya511]

I would have filled the tube with water and freeze it while carefully observing, the ice will push the dent out. Its cold work and takes many hours in the cold watching for just the right moment to stop the cold treatment, but the results are spectacular.

[@paulbrodie]

I don't think I have that much time or a freezer that big!

[@MrLethal1986]

Hi Paul any tips for removing a dent from a curved tube on a cruiser type frame. Any ideas how I could go about doing it would be much appreciated. Great content thanks for sharing.

[@paulbrodie]

I would use bondo. Scratch and sand it with 80 grit emery cloth, then fill and sand. Paint. Thanks for watching!

[@MrLethal1986]

@@paulbrodie I've found some other information on dent removal using compressed air and heat. It's normally used on exhausts and tanks but I've seen one guy do it on a bike frame and worked really well. Just in the process of making a attachment to connect the air line to my frame. Thanks for the reply.

[@paulbrodie]

@@MrLethal1986 Yes, that process has been used to take dents out of 2 stroke expansion chambers. I think you have to be very careful with how much air pressure and the amount of heat. Good luck!

[@lucretius123]

Hi, I have a much smaller dent In my steel frame. Maybe the size of a pea. I was wondering if it would be possible to cut a piece of chromoly length wise and braze it on as a sheath. I don’t think my frame needs a repair, just wondering.

[@paulbrodie]

If your frame doesn't really need a repair just fill it in with bondo. No heat, no warpage, just a little sanding and a little touch up paint.

[@raibt6093]

Dear Mr. Brodie, I've got the same frame, a RM équipe from 1993 with a dent at nearly the same position, but it was a little bit smaler. After I've seen your video I tried to roll out the dent with selfmade tube-blocks like you declared and it worked very well. Many thanks for your video. Finally I put grease between tubeblock and framedent so I could press it harder by rolling out the dent. At least there was nearly no high spot and no dent left. For heating up I unfortunately don't have the right workshop so I was contented with the little leaving dent. Many thanks for giving your idea. I don't dare to file the frame because the tange ultimate ultralight tubewall should have a thickness of 0.6 mm. Is it really without problem to file the frame? Yours sincerely Rainer

[@paulbrodie]

You don't have to file the frame. It sounds like you were careful and made it better. Congrats!

[@raibt6093]

@@paulbrodie Many thanks.

[@gweflj]

Paul, What about a bit of beeswax or linseed oil on those clamp faces?

[@richardcarew4708]

love watching you work... thanks for sharing your amazing knowledge... 👏 once upon a time I taught autoshop.. richest town in the Bay Area... my kids drove Mercedes and Jaguars... which is why they hired me ;;☆》.. of many jobs... it remains my all time favorite... my biggest problem was getting them to go home... big fun... an honor question: I usually use brazing rod with the flux on the outside... is the separate flux better?

[@paulbrodie]

Flux is flux. If you don't have an automatic fluxer a coated rod will work.

[@richardcarew4708]

@@paulbrodie back when I learned how to braze... I recall the guy mentioning that issue.. but I was in a hurry and didn't pay attention to the details... I figured I would figure it out... I use the coated kind simply because it is easier in the small applications I have had... times are changing... thanks Mr Brodie... it's been a pleasure, sir

[@paulbrodie]

@@richardcarew4708 I don't think flux coated rods are the very best solution, but much better than no flux at all.

[@jonasmeier417]

Hello Paul: Very interesting! I didn't know how dents are fixed. What would happen without fixing? Bending? Breaking? Does a frame lose static and stability with a dent or is it more an optical thing? Does it work only with bronze on a steel frame or would silver also do the job? Is it possible to repair also dents on aluminum frames? Thank you for replying.

[@paulbrodie]

Hello Jonas, If you didn't fix a small dent, as long as there was no sharp crease (to start a crack..), it would probably last a very long time. You could say most "small dents" could be considered cosmetic. As dents get bigger, a framebuilder has to decide when to fix and when to replace the tube. You can also use silver solder, lead, and bondo to fill the dent. I have never repaired a dent on an aluminum frame so no expert here. Thanks for watching!

[@BruceChastain]

great video man! one general question, does this filling in job help with strength or is it more cosmetic?

[@paulbrodie]

Thanks Bruce. I would say it's mainly cosmetic. If you don't have a set of torches, you could use bondo (auto body filler..) It works well too.

[@BruceChastain]

@@paulbrodie thank you Paul! I have a set of torches, well my dad does anyway. I’m planning on powder coating this frame so I suppose I’ll need to braze it.

[@paulbrodie]

@@BruceChastain You can powder coat over Tig, braze, nickel silver, and silver solder.

[@Vip-db2mq]

nota 10 ta de parabéns..

[@kenneely7899]

Could a stud be brazed on. Knock the dent out with a slide hammer? Great looking repair!

[@paulbrodie]

If it was a cheap frame with thicker hi tensile steel, yes. But thin wall heat treated 4130 steel, no. It would most likely crack.

[@danny-li6io]

I would leave that exposed, no paint, maybe an autograph though 😂

[@BinhNguyen-ex4zn]

can you do the same for aluminum bike frames? what would be different?

[@paulbrodie]

No, aluminum bicycle frames cannot be economically fixed. They just get re-cycled...

[@michaelhallas6450]

Theirs anyway you can pull the dent out with a unispotter (pinwelder) then fill it ?

[@paulbrodie]

You have to understand that not all bicycle frames are created equal. The cheap ones use heavier wall tubing, not much better than mild steel. The expensive frames use thin wall 4130 tubing that might be heat treated too. There is a world of difference between the two. What might work on one might not work on the other. Make sense?

[@garrisoncullen7476]

can you do the same if the frame is not cylindrical like a mountain bike downtube? I dented mine pretty bad first day i got it but its not cylindrical.

[@paulbrodie]

No, you can only roll a round tube.

[@dfreeze666]

Im not educated, is adding the bronze actually structurally helping the frame in the long run? Isnt that now a weak point? Or does the fill make it stronger like bone? I have Monẽ bars so i trust brazing, just new!

[@paulbrodie]

I don't think it's a weak point. Is it stronger? Probably not. It just "is"... I have never seen a frame fail at that point after being filled with bronze. The danger is Overheating the tube, so you do have to be careful.. Thanks for watching...

[@AbrahamBarberi]

Great video with great information. Question. I just purchase an 853 Reynolds MTB frame. The brand is Cotic, and was made in England. The frame has a much smaller dent that the one on the video. This is the question, since Im going to use this frame for MTB, do you think is still safe to use or should I get it fixed? Thank you!

[@paulbrodie]

Thank you Abraham. If it is a small dent, with no sharp edges, it should be fine to use. A sharp edge could cause a stress riser. A small dent is basically cosmetic. Thanks for watching!

[@AbrahamBarberi]

@@paulbrodie thank for the quick and good answer. Great channel!

[@stoneyswolf]

I purchased a vintage bmx frame off eBay years ago really cheap because the head tube is dented. It's a chrome frame so it needs to be perfect . I used a pipe expander to get it mostly out but still needs work. I'm trying to get it perfect if possible without needing to be re chromed because it's in really good condition for a 40 yo frame any suggestions.

[@paulbrodie]

It's not easy to make a head tube round. Keep pulling little by little. I think the key is patience.

[@pepekrozinek]

Paul, what is the deal with the custom dynafile? Does the twist in the belt help?

[@paulbrodie]

Just found your comment! I made the custom dynafile in 1985 and saved myself $400. The belt follows the same twist and bend as the original dynafile.

[@budchestnut9303]

Mr Brodie, Why not use a tack weld automotive dent puller? The type where you tack on a pull tab in the center of the dent and then after pulling you cut off and grind down the tab! Also can be done with adhesive pull tabs. I know steel tubing may be only less than .2mm wall thickness but if a snatch tool or puller were used gently it would raise those dent centers up and then the split blocks and body hammer could be used and so forth. Also to avoid heating the tube and weakening it I have uses 60/40 tin lead filler with a much lower flowing point to level up the low spot but now days the tack on dent pull is the way to go.

[@paulbrodie]

I know your method works on regular steel. Will it also work on heat treated thin wall 4130?

[@KondoriRamin]

You could use air pressure (inside the tube) to pop it up... That's the most efficient way to do it. You could also apply a little bit of heat to soften it up...

[@paulbrodie]

Yes I did watch a KZbin video where someone did that. I know that's what they do with motorcycle expansion chambers to get the dents out. Some bicycle tubes are sealed, others aren't. Downtubes, for example, usually have a big airhole going into the BB. How to seal that? I don't know.

[@KondoriRamin]

@@paulbrodie With a plug... Or you can even seal the end with a plate and then remove it. You do not need much pressure for that, especially if you heat the metal...

[@yzmoto80]

Yeah a little bit of a bend from your frame block and torquing the top tube back and forth.

[@stevenmorris1153]

would that brazing technique and the flame temperature be the same if I did that with a 7005 aluminium frame and 5356 filler instead of bronze filler? and would bronze filler work as good as 5356 filler for brazing 7005 aluminium? Thanks for the video.

[@paulbrodie]

I can really offer no opinion on aluminum frames, because I am no expert there. Any heat applied to an aluminum frame would mean softening of the material and the necessity to re-heat treat. That's one reason why aluminum frames don't get fixed or repaired as often as steel frames..

[@stevenmorris1153]

@@paulbrodie Thanks a lot for answering me

[@digambarpatil5785]

*Easy to setup and maintain.*

[@paulbrodie]

Exactly!

[@londonpickering8675]

That was simply therapeutic.......All is right in the world for 15:27.

[@paulbrodie]

Thank you London Pickering.

[@tomanycooks]

very interesting. does the braising strengthen the frame or is it for looks?

[@paulbrodie]

It might strengthen it a tad, mostly cosmetic.

[@saleemcarr9501]

100% cosmetic, this is not how to structural repair. One big bump or curb and the bike will fold in half

[@jsdhesmith2011]

Just picked up a Gary Fisher Hoo koo e koo that has about a 1/4” deep dent in the top tube like this frame had. I traded an old squier electric guitar for it, I didn’t notice the dent till I got home. The guy who traded with me only had pictures of one side of the bike, so I didn’t get to see it in pictures. Anyways, I’m thinking my dent is not so bad compared to this one but I’d hate to have the frame fail on me while riding. My question is, if I just ride around the city and some light trails (mostly gravel, no jumping) do you think I’d be fine to leave it alone? I would love to fix it but I don’t have a setup like yours. Thanks.

[@paulbrodie]

Josh, the top tube is not highly stressed so it should be fine. If it is going to crack, it will probably happen over time, not suddenly, so just keep an eye on it. Thanks for watching...

[@jsdhesmith2011]

@@paulbrodie Thanks for your input. I subbed

[@RICHARD.WRIGHT1]

Is that JOHN TOMAC in the photo on the wall next to that column drill in the background?

[@paulbrodie]

You bet! Good eye :)

[@birthaappleshirt7404]

So interesting. Does the brass act as a filler or does it add some strength?

[@paulbrodie]

The bronze is a filler and might add to the strength a little bit. Thanks for watching!

[@kokadedru5157]

why dont you use silver solder for this job to profit from the way lower heat? is it a price thing?

[@paulbrodie]

You could use silver solder. It has different flow characteristics than bronze, and might be trickier to build up. I've just always used bronze so that's what I'm used to. And bronze is less expensive..

[@deltafour1212]

When building road bicycles from Chromoly, what is the typical wall thickness do bike manufactures and frame builders use? What thickness would the bare minimum that you should use?

[@paulbrodie]

Common tubes are 9/6/9 and 8/5/8. This would refer to wall thicknesses of 0.9mm / 0.6mm / 0.9mm. 7/4/7 is also available sometimes but that is very sketchy tubing to use because of the thin-ness. Make sense?

[@deltafour1212]

@@paulbrodie THANK YOU! THANK YOU! THANK YOU!

[@paulbrodie]

@@deltafour1212 You're welcome. Go online to some of the companies selling bicycle tubing and you will see what is being offered...and the prices!

[@ardytjahjono9307]

Hi Paul. Great video btw 👍🏻. Can you do same approach to fix aluminum frame ?

[@paulbrodie]

Using frame blocks yes. Be very careful with heat. Too hot and the aluminum will lose its' heat treating..

[@ardytjahjono9307]

Do you accept dent and paint repairs? If yes what would be the best way to contact you for quick inquiry?

[@paulbrodie]

@@ardytjahjono9307 Sorry Ardy, I'm retired with a youtube channel...

[@ardytjahjono9307]

@@paulbrodie ah okok. Good for you. I think I might suggest my dad to also start a youtube channel, as he is a really good cook. Thank you Paul and GBU