edgewize

Here's a question I've been wonder about for a while. I am planning to bend up my own LG from 3/16th piano wire for a 120 size Delta wing. I have a bending brake and a wire bending jig and plan to make the front gear with a couple loop spring similar to regular front gear only larger scale. My question: Is it better to bend the wire cold, heat it red with a torch and bend, or heat it red, bend and then dip in cold water? I know it will bend easier if red hot but I don't know if this will make the bent area weak. Will quenching in cold water re-temper the steel?
Thanks

parrthd

you run into a lot of "if" s and "maybe" s when you deal with tempering steel AND with heating/retempering. not many people in our addiction.....er hobby has the equipment to handle the task you're describing. tempered steel is usually the result of a controlled process combined with the elements of the steel being used. most tempered steel is heated, cooled by air to room temp, reheated (not to the first temp), and then slowly cooled or kept at temp for a specific time, and then air cooled back to room temp. this is where you run into the ifs and maybes because the specific job the steel is being used for is geared to the elements of the steel and the tempering process being used. not knowing your background or your equipment you have on hand or access to i can do this: this is an excerpt from robarts installation manual for their mechanical retracts. i use this because you can bend the wire instead of using bolt on axles.

A. Using a torch, heat the area where the bend will be red hot. Continue heating while bending strut (or wire) 90 degrees (or whatever angle YOU need). (The wire should bend easily at red heat. If not, keep heating until bright red and/or use a small peening hammer to hammer a bend in place.)

B. When satisfied with the bend, remove from vise (or jig, brake, etc.) and quench in water. (I would use a 5 gallon bucket and drop the wire into the bucket to completely submerge the wire.) CAUTION: STRUT WILL BE EXTREMELY HOT, USE CARE IN HANDLING!

C. After quench, reheat bend to FIRST color change (grayish blue color) and let cool. DO NOT QUENCH AGAIN OR GET RED HOT!

hope this helps. I acutally have access to the equipment needed for proper hardening and tempering but for our use in this hobby i still use this method as it's simpler, easier, and doesn't require special equipment or taking to wire to work and missing my lunch break!!! LOL

vicman

My Feedback: (10)

Make sure you temper all the previously heated area if you choose this method,

Having quite a bit of heat treating experience, I never use the torch method for forming landing gerar. Even the spring for nose gear like you are wanting. I always form it cold. I have had piano wire that got too hot get weak quickly.