Rack Building Basics — Tools

This will be the first in a multipart set of blog entries with some basic information on rack building. I’m going to start by discussing tools. If you have any requested subjects please let me know in the comments and I’ll concentrate on them in future entries. The next entry will be about mitering tubing. I don’t plan on doing any entries around the use of a brazing torch, I think that you should learn that hands on from another person who is skilled in brazing.

My existing toolkit already had some of what I needed, such as a good vise and a hacksaw. However I also needed to buy a number of more specialized tools such as files, clamps, and machinists squares.

My most used tool is the vise. It supports tubing when I’m cutting it, mitering it, and brazing it. I have a pretty basic Japanese made vise that has 4″ wide jaws. I haven’t found the need for anything bigger yet when building racks, but this one is probably too small for mitering larger tubing used in frames. I often clamp rack sized tubing directly into the jaws of the vise, but it is better to make tubing blocks. You can see a homemade behind the vise. I have my vise mounted in front of the workbench so that I can access it from three sides. Framebuilders often have a vise mounted on a pedestal for 360 degree access.

My torch kit started out as a Victor Superrange II, but I quickly replaced a number of the parts. It would have been cheaper to buy a kit from scratch. I use Oxy/Propane (Oxy/Acetylene is more common). My welding shop swapped the stock acetylene regulator for a propane one. Propane doesn’t burn as hot as acetylene, but it is hot enough for brazing. It’s nice being able to use the same fuel tank as my propane BBQ. My oxygen cylinder has a 55 cubic foot capacity and that seems to last me about 6 months (maybe10 racks?).

I’ve upgraded the hoses to the Smith Kevlar hoses (around $50) and replaced the torch with a smaller and lighter Victor J-28. I primarily use a W-1J tip when making racks.

A great early project is a torch stand. This one is made from pieces of a BMX frame that I found in the trash. The stand lets me keep the torch turned on when I need to put it down for a minute and also holds short pieces of brazing rod andmy striker.

A lot of small tools are involved in making racks. I laid out some of them on my workbench. From left to right we have:

  • Drill and bits
  • Tubing bender
  • Clamps (Kant Klamps are the specific brand)
  • Pliers
  • Shop cloth or production cloth. This is sandpaper on a roll and 1″ or 1.5″ wide. I buy 80 grit shop cloth and a roll seems to last a long time. Enco has it pretty cheaply.
  • Sharpies are really useful for marking on steel.
  • Machinists squares in a couple of sizes are useful for keeping things square. Enco has a small kit for $20 with 4 sizes.
  • Vise grips are useful for clamping fixtures.
  • Round files are useful for mitering. More on this in a future entry.
  • A welding magnet can also be useful for clamping.
  • A center punch makes drilling holes in tubing much easier. You need to drill small vent holes in most of the tubes that you braze.
  • Sitting under the center punch is a deburring tool. It cleans up the inside of tubing nicely after you cut it.
  • Brazing flux and a flux brush.

You need to wear some sort of eye protection when brazing. These safety glasses are special in that they have didymium lenses with a flip-up #3 brazing lens. They are large enough to fit over my regular glasses (yup, I look like a dork with three pairs of lenses on my eyes). You can get them from Sundance Art Glass. Without didymium the flame and flux produce a bright orange sodium flare that is very difficult to see through. It makes it hard to see the underlying metal,which is necessary to know when the flux is getting hot enough (it turns glassy) or the steel is getting too hot (it turns orange). Here is an example without the glasses:

Can you see anything under that huge orange flame? I can’t. This is what happens when you put the glasses on:

Whoa. That tube is too hot.

The glasses are expensive and a luxury,but they are a really useful luxury. I think that they help my brazing quite a bit.

20 Comments

  1. Moz says:

    Cool. Looks good, if a little on the small side. I assume there’’s more space behind the photos.

    By sheer coincidence I got my welder today, and had to test it out by welding up my new workbench :) You”re making me wonder whether I should mount one of my vises forward of the bench. I have a 6″ Record engineers vise (35kg, going on $US200) that I”m going to mount flush with the front, but the wee 4″ swivel vise could easily go proud of that face.

    The tubing bender and Kant clamps look interesting, for when I have spare money again. What do you use for clamping tubes at funny angles for brazing?

  2. AlexWetmore says:

    My workbench is too small (3”/1m wide). Long term we”re planning on building another workshop and that”ll have a reasonably sized workbench. This one is actually a potting bench that I built for Christine, then took back for my own needs. It is not only too small, it also isn”t all that sturdy.

    I”ll have a future entry on how I clamp tubing to hold it in position while brazing. I”m still learning tricks here.

  3. bill connell says:

    Thanks for starting this series, it’’s very helpful to see photos of your setup too.

  4. Aaron says:

    Thanks for putting up the info. I am excited to watch the blog grow. I have a probably difficult question to answer, but about how much would you say a basic brazing set up would cost? Just curious on a ball park figure assuming one has a basic workshop with a vise already and just needs to acquire the tools specific to brazing and rack building. I am sure there are lots of variables, but even rounding to a $50 or $100 mark if possible. I am just trying to get an idea of how expensive a hobby it would be to start up. Thanks in advance for any response.

  5. AlexWetmore says:

    Costs really depend on many things (used vs new, online vs retail, brand name vs no name, level of equipment).

    Brazing equipment: I”d expect to pay about $300-350 for regulators, torch, and hose. With a kit you can save about $100 on that, but you probably won”t find a kit with the lightweight hoses that are nicest for brazing. My welding store sells 20 cubic foot O2 tanks for $60 and 55 cubic foot ones for $120 (the refill price is about the same). Glasses were around $70. I used an existing propane tank.

    Tubing benders are $50 to $200 depending on the size of the tubing and quality. The best bang for the buck is probably Ridgid’’s 5/16″ bender which runs about $60. Files are under $10 each and you can start with just a few.

    This should get you started. I might revisit tools with an entry on sources and prices.

  6. Mike Jenkins says:

    Great start, Alex! I see you have your high pressure oxygen tank secured to the column: very smart.

    Have you done anything about ventilation? Do you think it is necessary?

    One of the areas I would like to see you talk about in the future is fixturing.

    Thanks!

  7. AlexWetmore says:

    I have the tiny little workbench because this is the closest work area to my back door. I keep the door open when brazing.

    Long term we”ll be building a detached workshop and that will have ventilation as one of the considerations when building it. I want to be able to brew beer out there too, and that has even more significant ventilation requirements.

    Fixturing will be an ongoing theme. Tonight I”m hoping to spend some time on the fork crown mount of a rack and I”ll show how the options for fixturing with that.

  8. Adam Alpern says:

    Thank you for this series – it’’s fantastic! If I ever have a proper space to do it safely, I”m getting a torch and starting in on racks and frame mods myself.

  9. Dan Boxer says:

    Great series Alex. I enjoy reading how other people do this stuff.

    Do you ever find that the heel of your torch hand inadvertently changes the flame setting while brazing?

    At UBI, they suggested we turn the torch tip 180 degrees away from the knobs. This way, the knobs are always facing the same direction as your palm – as in away from yourself if you were to wave “hi” to someone.

    I use my torch this way and never have a problem with the flame setting changing mid-braze.

    I brazed a small, rather tippy, torch stand that I can leave on my frame fixture cart thingy or move to my workbench next to my vise. No pics of this yet, but soon come on that. I keep my stricker in my shop coat pocket – always handy and the shop coat puts me in a certain mood. Not very much unlike Mr. Rogers and his cardigan sweater and tennis shoes. WEIRD.

    I second the recommendation to purchase individual brazing components – over a full kit. I spent a fair amount on my Victor kit and only use the regulators, torch handle and two tips. I just bought a smaller diameter hose (non-kevlar) and prefer it over the heavy duty, large diameter rubber hose that came with the kit.

    I also just refilled my acetylene tank (50cf, I think) after nearly two years of use. I”ve built most of one frame, one fork, one trailer hitch, much of an on-going/dead? trailer project and a lot of messing around. I”d prefer to get more frames and forks out of this tank and in less than two years time!

    Didymium glasses and #3 or #5 shades are a great combination. Face shields are also nice if brazing larger/hotter items.

    Looking forward to more on this, Alex.

  10. AlexWetmore says:

    I hit the knobs all the time when I used my old torch (the one that came in my kit, I think it was a 150FC?). The little J-28 torch that I”m using now has the knobs near the brazing tip instead of at the base of the torch, so I don”t bump them. I can actually adjust them easily with one hand which is nice. Not necessary, just nice.

    I need a shop coat. I have an apron, but almost never wear it (and have the stains on my day to day clothes to prove it). I try to keep my striker on the torch stand, but it often ends up sitting on my workbench under a pile of tools.

    I”m glad that you are enjoying the series.

  11. Scott Atwood says:

    What a great series. I”m looking forward to the other entries. I”m especially curious about painting them. And also the mounting section to the braze-on. Can”t figure that one out, using hollow tubing and all.

  12. Dimitris Adams says:

    First of all I would like to give you congats for your hi-end blog! I am big fan!
    I am planning to build my first custom touring lugged frame using tubes from Columbus. I would like to ask you something about the brazing method. I asked my welding shop and they told me that the cheapest and easiest method of brazing is using MAPP/Oxy setup instead of Oxy/Acetylene setup. One disadvantage of MAPP i discovered (from web):
    ” The MAPP/oxygen flame is not entirely appropriate for welding steel, due to the high concentration of hydrogen in the flame – higher than acetylene, but lower than any of the other petroleum fuel gases. The hydrogen infuses into the molten steel and renders the welds brittle. For small-scale welding with MAPP this is not too serious a problem as the hydrogen escapes readily , and MAPP/oxygen can in practice be used for welding small steel parts.”
    I saw that you are using MAPP. What is your opinion about that. Should I go for MAPP or should I buy an Oxy/Acetylene setup. Thanks in advance. Many thanks also for the information you are sharing with us with your blog.

  13. Dimitris Adams says:

    of course you don”t use mapp/oxy…you use oxy/propane…anyway if you know anything about mapp/oxy just let me know.
    Thanks

  14. Alex Wetmore says:

    I use Chemtane/Oxy, which is pretty similar to MAPP/Oxy.

    What you”ve read is true for gas welding, but brazing is not gas welding. Chemtane/Oxy works great for me for brazing. I haven”t tried gas welding with it, but there are no gas welding operations necessary on a bike frame, and few framebuilders do any gas welding.

  15. Adam B says:

    Cheers Alex.

    You”ve mentioned sources for the 4130 you”re using, but I didn”t find a discussion of your brazing rod and flux choices. Also, where you get them from.

    Thanks for the great info!

  16. Alex Wetmore says:

    I mostly use Gasflux rod and flux, but are available from henryjames.com.

  17. Ray Hastings says:

    I”m really enjoying your blog, has really helped me out a lot. Do you have any issues with 90 degree bends on 516 .028 wall 4130 tubing flattening out? I am using a Rigid 600 series, model 38038 bender. Looks pretty much luck the Swagelok benders. The Swagelok documentation rates their benders for a wall thickness of .035-.065 for 516 tube, maybe the wall thickness is too thin and the tube is crushing a little? I may try filling the tube with sand or freezing water in it before I bend it next time.

  18. Alex Wetmore says:

    I haven”t had trouble with that flattening out. I”m using the cheaper Ridgid bender for 5/16″ tubing, that one should be higher quality.

    I have built many of my racks with 5/16″ x 0.035″ perimeter and legs, and 0.028″ for internal cross bars and backstop. Doing a hybrid like that might allow you to get better bends without making the rack much heavier.

  19. Ray Hastings says:

    I just noticed the zip ties holding the clip on shade on your didymium brazing glasses. I have the same issue, the top of the glasses is too thick, the clip on, won”t grip it properly, wants to ride up. Did you remove the existing clip on mechanism or just force it with the zip ties? I need to do something similar with my set up.

  20. Alex Wetmore says:

    I just added the zip ties to try and hold it in place. They”ve never been ideal, the setup is just a bit fussy. There has been recent discussion on the Framebuilders list about glasses and another supplier came up that I might check out in the future. You can find that list on Google Groups, it is just called “framebuilders”.