Stay Mitering Fixtures: Anvil Vs. Sputnik Vs. Homemade

[Joe Graham]

Hi All,

I'm struggling with a purchase decision (what good cyclist doesn't) and am looking for some more experienced voices to help out. I am a new builder (12 frames) and am trying to improve my process and build speed. I built a very basic tube mitering system (works like a horizontal mill but uses a drill for power) that does well with the main tubes but struggles with the chainstays and seatstays. This is a problem because I spend a lot of time filing to get these miters decent when really, given my welding experience, I should have them perfect to help my welds. Here are the solutions I'm considering:

Option #1 Anvil Chainstay Fixture
I have an Anvil Journeyman frame jig and am super pleased with it. Not only does it work super well (based on my limited experience) but it also has the bling factor. Right or wrong (probably wrong) that bling factor is impressive and helps me gain customers confidence. The Anvil Chainstay fixture looks like it will work really well for my needs, and I believe I can "cheat" with it and use it for both chainstays and seatstays.

Option #2 Sputnik Chainstay Fixture
The $300 difference between the Anvil Fixture and the Sputnik one isn't a huge issue to me. I'm curious if one has an advantage? The big advantage I see is the Anvil fixtures use of v blocks, they seem more able to handle different tube shapes. Has anyone used both to say if one of better than the other?

Option #3 Homemade
I've been trying to find a good milling machine but I have been avoiding purchasing heavy equipment because of the challenges they present when moving. I don't own my shop space and am not sure how long I will stay. However, assuming I purchased a mill or used a local machine shop, how likely is it that I could produce something better (or similar too but cheaper) than the two options above? I know many builders have made their own fixtures, is this just to save money or have they created something better?

A big thanks in advance to anyone who can help me out with this. Also, I just moved to NH in the last couple weeks and if any nearby builders read this I would love to come meet them!

Joe Graham
Graham Cycles
Marlow, NH
Grahamcycles.com
http://www.flickr.com/photos/grahamcycles/

[jon norstog]

Joe, list:

I've been using the Anvil chainstay fixture a couple years with good results.  I use it with a vertical mill, not the best set-up IMHO which you find out when mitering seatstays. 

I also use the chainstay fixture as a jig when welding or brazing up chainstay and seatstay assemblies.  So mine is a bit scorched.

The Anvil seastay fixture works but could really benefit from some design changes, at least as used with a vertical mill.

The main reason for using the fixture is accuracy, not speed.

good luck

jn

"Thursday"

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[Wissahickon Cyclery]

Joe,

I have owned all the mentioned products (although both of the older version) and will offer my positives of the products.  The Sputnik seat stay fixture is without a doubt the best product available to miter seat stays.  Few could improve upon the design.  It miters very accurate CENTERED seat stays every single time.  This centered cut requires stays that are symmetrically bent and that the fixture is properly indicated on the mill and on the center line of the spindle.  The design works incredibly well, is super rigid, never dings the stays and is very fast to set up.  As with all fixtures it is best if you can dedicate a machine to it or you will have to indicate it every time you use it. 

I honestly feel the features that differ between seat stays and chain stays will make it not worth the effort to use the same fixture for both.  The chainstay fixture is IMO the most important part of making a bicycle.  It controls all aspects of alignment (that matter most) and if you have your chainstays the same length and the drop outs (and stays) in phase you are heading in the right direction.  I currently use a fixture I made and yes I made it because I felt mine is a better design for how I build bikes than the offering out there.  Making fixtures is not for saving money but to get something you know will work well for your process.  At a certain point you will know if you have the skills to make fixtures.  It takes time, patience and money (to buy material more than once since you will change your mind and design).

Fixtures are IMO for repeat-ability and accuracy. Most things can be done without one but require lots of thought and patience.  Once you understand why the fixture works and how it works a light bulb will go off.  Now it would become more apparent how to achieve the end result without it (the fixture) but by that time you already have the fixture. Plus you still would not get it done as fast.  

I will end with this.  Machine tools are not the end all be all to making bikes.  They do require some skill and respect.  They are a huge part of my process but I spent a ton of time learning how to use them and get the most out of them.  If you have an interest in the mill or lathe you should get one.  Moving them is not that big of a deal.  Pipes, a Johnson bar and some other basic equipment go a long way.  Having a pick-up (or a friend with one) also is a huge bonus.  Renting a trailer is even better since the item is even lower to ground to start.  Go visit Joe at Plaza Machinery in Vermont.  It will be worth it even if you leave with nothing.  He is a great guy.

Cheers,

Drew

--
Drew Guldalian
Wissahickon Cyclery
7837 Germantown Ave Phila,PA 19118
www.wiss-cycles.com
www.engincycles.com

[Meriwether]

One thing to consider on price - the Sputnik sounds cheaper until you get the tube blocks you need. I think he charges $100 for each additional sized tube block. So your setup could be only $600 if you only use one diameter tube or it could quickly reach the Anvil's pricepoint if you use different diameter stays.  I have an Anvil CS fixture and I'm not sure how I'd safely set it up for seatstay mitering.  I'll have to look at it that way next time I'm in the shop though, it would save a bunch of money.

I made a 80/20 stay mitering 'fixture' that's totally junky but it is possible and it does work better than it looks.  But if you are looking for a good but cheaper option look at Alex Meade's fixture.  He is great and is willing to custom make the fixture and tube blocks to your needs. 
http://www.alexmeade.com/Tools.htm

Whit

[Hubert d'Autremont]

Hi Joe, 

I thought I would add my two cents in on this. 

I will agree with Drew on machine tools need a lot of patience and respect. They can be a huge help but take a lot of time in terms of how to properly use them as well as to tool up. Machining is a whole trade in and of itself and you can ask my painter if you want to know how much time I end up working with machines v. building bikes. That said, I love machine tools and my process at this point (it didn't use to) heavily relies on them, again what Drew said on accuracy and repeat-ability.

I have used the anvil stuff and some of the sputnik stuff, some of it I like and some of it I didn't. There are always going to be limits to each style of fixture. 

As far as chainstays go, here are a couple. Some guys keep this really simple and do one stay at a time. I think Peter Weigle and Brent Steelman both do this, but I am not positive, look on their flickrs. 

This can be done accurately but isn't as fast. It also reguires that the cutter is centered on the stay. The reason for this is that one stay will be upside down, that is if you don't change the angle of the fixture( which I wouldn't). Some builders like to cut the stays off center, generally to gain a little more clearance between the seat tube and the top of the stays. You could do this with a single stay fixture but you would have to touch off each stay and move the table, not as accurate and beats the speed of the process. 

The Anvil Chainstays fixture, or at least the one I used, had a t slot, this required that their was something to spread the stays apart. On the older one at least it spread the blocks, which I did not like. also the tolerance on the block varied so even it you had something to spread it, it could only get you so far.

The sputnik self centers with pivoting blocks which is really nice, because then it will always be centered, the drawback is that you can't necessarily hold the tightest tolerance on length. That said I'm talking about thousandths here not mm's so plenty good to trust your eye, it is calibrated better than most machines. I'm sure you could figure out how to do it perfect but I haven't bothered.

As far as the Seat stay fixture, the Anvil has similar problems to the chainstays, it works but takes some patience. The sputnik is nice, but what I don't like about either is that there isn't a great way to get your cut length, generally this means that you have to cut the stays twice or file it to fit. 

I built both my seatstay and chainstay fixtures and am please with them, though there are things i would definitely change. My chainstay fixture is almost and exact copy of an earlier one of Drew's and I like it. 

For my seatstay fixture I wanted something that would rotate on center so I could control both the cut length and angle. The rotating part on center is really tough because you either need to have a giant rotary table(which you then run into clearance issues) or make a set of plates that have an arc in them up to 90 degrees. I did this and had a few problems. Ultimately, though because I knew all the tolerances, I ditched this and put the whole thing on and angle plate. I can calculate my center so I can touch off and move the table to position it. Ultimately this fixture is a beefed up version of the anvil with better tolerances, it would be a million dollars to produce it...

Sorry if this is confusing, what it should convey is that tool making can be a serious rabbit hole and you might not even get the results you want in the end. 

I will second going to see Joe at Plaza, I go hang out with him at least once a month and he has become a good friend and a great resource. The best thing to do is to go up and poke around, his list gives only a sense of what is there. 

If you feel like making the trip all the way up to Burlington, I'd be happy to show you some of the stuff I've made. Also you are pretty close to FTW. You should go him, the guy is OG and has built more bikes that this list combined...

Just kidding guys. 

Hubert d'Autremont

BTV