Wall thickness on tubing. What do you run?

[SlinkySam]

I am sadly a little frustrated with trying to solder my brake tubing (I need to clean it better I presume). In my rounds of looking for possible easier solutions, I came across several places selling 1/4" OD steel tubing for a decent price. My only question was, what wall thickness are you guys running? I found some with an 0.035" wall and an 0.049" wall which to me seemed a little thin, but maybe I am wrong. I don't have my calipers on me to get the visual. It runs only $1 a foot for Carbon Steel Seamless Tubing.

Thanks

-Sam

[rckjeep]

Hey Sam, mine is on my tube buggy is .035. I could stand on the frame without any flex at all. I know you can't solder it though. At least not any way I tried. Where did you find cheap tubing? My source has quadruplied in price. I think I spelled that right. I just looked at my old order. I paid $1.31 a foot and now it's $8.90 a foot.

[SlinkySam]

Well, I was thinking of welding it since I have my mig just sitting doing nothing. A tad overkill though for this kind of project. I also have an aluminum gun attachment so I can do that too. I have never tried it, but one of these days I should learn how.

As for this tubing that I found, I went to good old McMaster.com. Home of all the greatest stuff, but at rediculously high prices at times. That is ok though because you can find just about anything there. Maybe their prices haven't gone up since they have bulk of everything and haven't had time to adjust prices.

Here is a link:
http://www.mcmaster.com/
Go to Metal Tubing in the options, then go to page 107. They also have other great metals as well including teflon coated steel..... dig it.

Oh and the correct spelling is "quadruple".

-Sam

[SlinkySam]

Oh hey RckJeep, weren't you looking for some bearings? If so, they have them in 4x11x4 mm and also 5x11x3 mm in stainless. That is shaftsize x OD x width. And you can have it all at a rediculous price of 6 to 8 bucks in either shielded or open design.

-Sam

[rckjeep]

ya I'm looking for 6x11x4

[JakeDaSnake]

Hey man, I would try to braze it before I tryed welding it... Lowes has a MAPP GAS/OXYGEN torch with the brazing rod for $49.99 it gets almost as hot as OXI/ACETYLENE , I used a brass brazing rod with a flux coating so no liquid flux is needed... its easy...

Later
Jake

[roktoy]

Yep....solder won't work. I braze all mine. I have tried MIG and can do it but the joints come out kinda bulky (to scale) and chassis revisions are a PITA.

I believe the SS tube I've been using is about .030" wall.

Jay

[Smurf]

.120 wall dom thats what you should use.

[SlinkySam]

Many thanks guys for the info on your techniques and materials.

One question I have for those brazing. Are you doing multiple joints at the same time or using a pencil thin torch for the work? Not being to familiar with brazing / soldering, etc., I have been using a mapp gas torch that I had for doing all the copper piping in my house. Copper piping work is cake work compared to a chassis build.

So I ask this technique questions because I went and did one joint and realized that I had another right next to it. As soon as I heated up the metal it popped apart and I had to redo it. These are simple minded questions on technique, but I just have to ask anyway.

-Sam

P.S. - Jay, a little off topic, but I am curious. A few years back you took some pictures of me and my Slinky going through the box in the "Carnage on the Con" competition. I was wondering if you might have those in digital form for a background image on my desktop. After all the rollovers, she just doesn't look as nice as back then. Thanks.

[JakeDaSnake]

When I biult my chassis I made extra care to get the pieces to fit close to perferctly and they shouldn't be under any stress so they shoudln't pop apart, I just started my new chassis tonight and did one joint and then did another right next to it...

Later
Jake

[roktoy]

Originally Posted by SlinkySam

One question I have for those brazing. Are you doing multiple joints at the same time or using a pencil thin torch for the work? Not being to familiar with brazing / soldering, etc., I have been using a mapp gas torch that I had for doing all the copper piping in my house. Copper piping work is cake work compared to a chassis build.

Ha ha....yeah, there's no socketed fittings :-)

Sometimes I'm doing a single joint, other times multiple joints converging at the same node. Gets a little tricky but with a small micro torch I can kinda aim the heat where I want it.

Originally Posted by SlinkySam

So I ask this technique questions because I went and did one joint and realized that I had another right next to it. As soon as I heated up the metal it popped apart and I had to redo it. These are simple minded questions on technique, but I just have to ask anyway.

Yes, that can be a problem, but using a small torch helps. This can also be minimized by noting the order in which joints are brazed. Sometimes I will braze a joint just enough to make it stick but not full heat/flow the whole joint. I may then add another tube that would help support this one or another one I may be concerned about moving. Then you can come back and fully heat the joint as needed.

Originally Posted by SlinkySam

P.S. - Jay, a little off topic, but I am curious. A few years back you took some pictures of me and my Slinky going through the box in the "Carnage on the Con" competition. I was wondering if you might have those in digital form for a background image on my desktop. After all the rollovers, she just doesn't look as nice as back then. Thanks.

I was shooting only color slides back then. If you're interested in scanning to get a digital copy I can dig thru my files and see what I have....lemme know.

Jay

[SlinkySam]

Excellent information. I thought I was going nuts trying to get the chassis to come together. I like the brazing strategy you mentioned RokToy. I just jumped right in and started bending and brazing without too much fore thought. However, I can see my errors now. Time to get back at it.

Thanks guys.

Oh, Jay, that is cool. No reason to make you dig though. I have plenty of pics, but the Carnage on the Con was a great experience. I have the magazine article and Rear View Mirror page up on the wall in the garage. Thanks for taking those shots and getting them into the mag.

-Sam

[SlinkySam]

OK, to update on the tubing issues I was having; I have been messing with the old brakeline now trying to "beat" it into submission to actually weld together. Well, after many tries with super cleaning the metal and multiple method attempts, I gave up. I am not sure what the brake line is made of, but I want to believe it is the material giving me headaches. I can actually see crap when I am heating it up too. There isn't that nice consistent glow across the metal.

So out came the tubing I bought from McMaster. What a huge difference. Somewhat like butter in comparison to the brake line. My first attempt went real well comparatively and was clean to the glow. So now I guess I will restart bending tube again since the first chassis is barely acceptable. Luckily I didn't get too far. I also wasn't happy with the design after seeing how slick RckJeeps came out. Here was my chassis as far as I got before I got frustrated.






Here is my latest brazing test which came out ok I think. Maybe a little more fill in the groove, but then again, I didn't notch it completely.



Also, in my frustration, I didn't clean it off. So there may have been a light oil on it from McMaster for storing purposes.

This pic is straight from the brazing without any cleanup. I am worried about impurities from heating it too long or moving the braze around a bit. Either way, it is fairly strong from my limited attempts to break it apart.

My next task is to find a better micro torch than my copper plumbing Mapp gas torch. So back to bending for me.

So far, the fairly cheap seemless tubing from McMaster gets my thumbsup.

-Sam

[roktoy]

I have found that brakeline finish and hardness seems to vary some.

When I was still using brakeline I found the stuff from my local Pep Boys worked best, but I don't recall their supplier name.

Some brakeline is galvanized so be careful as the burning fumes can be poisonous and make you ill if you breathe it much.

Jay

[NewBombTurk]

Originally Posted by rckjeep

Hey Sam, mine is on my tube buggy is .035. I could stand on the frame without any flex at all. I know you can't solder it though. At least not any way I tried. Where did you find cheap tubing? My source has quadruplied in price. I think I spelled that right. I just looked at my old order. I paid $1.31 a foot and now it's $8.90 a foot.

$8.90 a foot??? Is this steel tubing or PLATINUM tubing? McMaster has .250" steel tubing for $8.57 for a 6ft length. Maybe you should re-examine your supplier/source.

[SlinkySam]

Originally Posted by roktoy

I have found that brakeline finish and hardness seems to vary some.

When I was still using brakeline I found the stuff from my local Pep Boys worked best, but I don't recall their supplier name.

Some brakeline is galvanized so be careful as the burning fumes can be poisonous and make you ill if you breathe it much.

Jay

I would say at this point that brake line is not worth the effort. I filed all the joints for quite some time and I was still unable to make it acceptable for brazing. The effort wasn't worth the savings in cost or local resource. McMaster was cheap enough and delivered to my door at a fair price. I just wish I figured that out sooner. Now's the time to start practicing with the new material.

Thanks for your info Jay. Very helpful to this R/C newbie.

-Sam