Curti Posted December 18, 2011 Share Posted December 18, 2011 Pictured is 3/16 rigid brass tubing. I can buy the tubing at my local hobby shop, no problem , but bending it is. What is the trick? My brake tubing bender dosn't come close to the small radius needed for this application. :confused: Link to comment Share on other sites More sharing options...
Guest Posted December 18, 2011 Share Posted December 18, 2011 How about adding just a little bit of heat before you put it in your tube bender.Don Link to comment Share on other sites More sharing options...
Matt Harwood Posted December 18, 2011 Share Posted December 18, 2011 Have you tried those springs that fit over the tubing so you can bend it by hand and not kink it? I have a set that I bought at Home Depot that I use for bending those small-diameter hard lines for toilet tanks and sinks that are decorative. You should be able to buy a kit that includes 4 or 5 different diameters. I don't know if you can bend it as sharply as shown in the photos, but it will work better than trying to do it by hand and not kink the tubing.Hope this helps. Link to comment Share on other sites More sharing options...
wmsue Posted December 18, 2011 Share Posted December 18, 2011 Hi Curt,Have you tried bending it around a pipe?I use to fill the tubing with white playground sand, cap the ends and heat the section I want to bend. Once a nice wide section is heated, I'd hold one end tightly and wrap the tubing around the pipe. The pipe is usually mounted vertically in a vise or in some cases it was the support pipe holding the ceiling. Depends on the size of the bend. I've never tried it with brass though. How expensive it the tubing?Let us know what works Link to comment Share on other sites More sharing options...
Tom Martinez Posted December 18, 2011 Share Posted December 18, 2011 How about this Mcmaster-Carr product? a little pricey but something similar can be found elsewhere I'm sure. Item # 242185, or just go to their site and search tube benders.I'm guessing the tube is for vacuum wipers mounted in an open car? I'm about to bend the same size tube for 31 Lincoln convertible coupe.-Tom, So cal Link to comment Share on other sites More sharing options...
Curti Posted December 18, 2011 Author Share Posted December 18, 2011 Thanks for the quick replys fellas! Yes, they are vacuum supply lines for an Auburn speedster. I went to Mcmaster, 242185 dosn't come up, the part numbers all have an alpha character. The smallest radius is about 1/2" I think a combination of the suggestions will be in order.sand, heat, a bolt of the radius needed clamped in a vice. and maybe the spring over it.And Ov-Gloves so as not to burn my pinkies. I'll post the results. Link to comment Share on other sites More sharing options...
JV Puleo Posted December 18, 2011 Share Posted December 18, 2011 Another technique was to fill the tubing with wood's metal, a very low heat melting alloy. After its bent, just immerse in boiling water and the filler will come out. Link to comment Share on other sites More sharing options...
Guest De Soto Frank Posted December 18, 2011 Share Posted December 18, 2011 A friend whose trade was repairing brass band instruments once related the trick for bending tight radius bends in brass tubing w/o kinks was to cap one end of the tube, fill it with melted pitch (pine tar or similar stuff), let it cool, then carefully bend the tubing to the desired shape ( cold ), then heat the formed piece until the pitch ran-out.Fine sand would probably do the same thing for your project. Link to comment Share on other sites More sharing options...
Guest sscargo Posted December 18, 2011 Share Posted December 18, 2011 It might help if you anneal the tube prior to bending. Simply heat the tube until it starts turning red and then quench in water.TTFNMat Link to comment Share on other sites More sharing options...
Tom Martinez Posted December 18, 2011 Share Posted December 18, 2011 Oops, meant 2421A5, it says it can bend a 7/16 radius, anyway, it looks like you have a truck load of ideas. I was contemplating using a copper tube but I'll be chrome plating the end that sticks out at the top of the windshield so I thought copper would be too soft.Tom In Cal. Link to comment Share on other sites More sharing options...
TexRiv_63 Posted December 19, 2011 Share Posted December 19, 2011 Curt,If you still have trouble try Cunifer tubing, it bends like copper without the work hardening problem and polishes up to look like nickel, great stuff. Link to comment Share on other sites More sharing options...
Roger Zimmermann Posted December 19, 2011 Share Posted December 19, 2011 Another technique was to fill the tubing with wood's metal, a very low heat melting alloy. After its bent, just immerse in boiling water and the filler will come out.Interesting what is coming on this forum!Could you please tell me more about that wood's metal? It could be the solution to fabricate the exhaust lines of my Continental scale 1:12. Don't tell me that I can buy it at this or that store, I'm located in Switzerland... Link to comment Share on other sites More sharing options...
Curti Posted December 19, 2011 Author Share Posted December 19, 2011 Well, here is what worked for me:Threaded the inside of both ends of the tubing with a #8 tap. screwed in a machine screw for a plug. This is 3/16 OD tube, the ID is ideal for light threads. Filled the tube with beads from the beadblaster, tapped it down so as to compact it. When it is full insert the second machine screw. Anneal the first and tighest bend. Bend ONLY with my fingers. ( I damaged one by trying to bend it over a bolt.) Unscrew the machine screws and pour out the media. Link to comment Share on other sites More sharing options...
Guest De Soto Frank Posted December 19, 2011 Share Posted December 19, 2011 Interesting what is coming on this forum!Could you please tell me more about that wood's metal? It could be the solution to fabricate the exhaust lines of my Continental scale 1:12. Don't tell me that I can buy it at this or that store, I'm located in Switzerland...Roger, Try an internet search on "wismuth"... it involves a technique used to fill engraved lettering with metal after the surface has been painted or otherwise finished...It was how the engraved lettering was "filled" on the top-plates of black-painted Leica cameras in the 1920's and '30s, to name one application.Regards, Frank Link to comment Share on other sites More sharing options...
jdome Posted December 20, 2011 Share Posted December 20, 2011 Similar to woods metal (maybe same thing), McMaster-Carr sells a product called "Cero Bend." It is a lead type alloy that melts at 180 degrees F. Link to comment Share on other sites More sharing options...
Roger Zimmermann Posted December 20, 2011 Share Posted December 20, 2011 Thank you Frank and jdome. Google had a good search result with woods metal; wismuth leaded to bismuth which is the base metal for the woods metal. I even found a store in Switzerland where I can buy it.. Not cheap, 100 grams for about $ 90.00. I will give it a try; I may use that metal for other applications for the scale model.Everyday there is a chance to learn something! Link to comment Share on other sites More sharing options...
Bhigdog Posted December 20, 2011 Share Posted December 20, 2011 I've heard that musical instrument makers bend tubing by filling with water and freezing it. Having had pipes burst from freezing I'm dubious but it might be worth a try. Heating the water first to drive off dissolved gases might help...........Bob Link to comment Share on other sites More sharing options...
Owen_Dyneto Posted December 20, 2011 Share Posted December 20, 2011 As an alternative to using Wood's Metal, you might look for Rose Metal. Same general family, about 50% Bismuth, melts at about the boiling point of water. As others have said, using either is a fine and classic method for difficult and tight bends. Link to comment Share on other sites More sharing options...
Guest car crank Posted December 21, 2011 Share Posted December 21, 2011 Rotometals has the Wood's Metal for $15.99/lb about 2.5 cubic inches.Low Melting Bismuth Based Ingot 158 ALLOY Wood's metalI use Wood's Metal all the time for bending thin wall tubing and could always use a couple more pounds. Neat stuff, but it can be a bit persnickety. You have to soak the tube in oil so it doesn't tin the sides (brass tubing). It is also very brittle along the crystalline boundaries and if you let it cool slowly the crystals get really big (around 1/4 square), so I quench it in cold water as soon as I pour it to keep the crystals small. That keeps it from breaking and coming through the tube. I also find it is much more pliable if you soak it for 10 minutes or so in hot tap water before bending. Aside from the tinning issue, I don't think any of these are concerns if you use it for fixturing. It's really cool stuff. Link to comment Share on other sites More sharing options...
DavidAU Posted December 22, 2011 Share Posted December 22, 2011 Another company that sells this type of material is PRODUCTSSeems to be amazing stuff. never knew it existed. As they say, you should learn something new every day. Link to comment Share on other sites More sharing options...
Restorer32 Posted December 22, 2011 Share Posted December 22, 2011 If you ever see a magician bend a metal spoon with his "mind" it is actually the heat of his fingers rubbing the spoon and melting the Cerometal spoon. Fun stuff to play with. We have used it to secure odd shaped pieces into a box so we could clamp the piece to a milling machine for milling. Expensive but it lasts forever. Link to comment Share on other sites More sharing options...
.thumb.JPG.5df7f52020fde2a60dd43a2286ce227d.JPG)
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now