Yeah not fatal 
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@Mikenopolis , please inform me if @moon is intending to be sarcastic, I’m too sofa king retarded to tell
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I wasn’t. I’m agreeing with you
Ok, I am no expert at this. I was just thinking of a wagly related case where lotus bonded alu chassis together, they had pips ensuring 0.2mm gaps for uniformly glue on the bonded surfaces. Also the surface roughness could have something to do with it, if the kingpin is super smooth and out if spec for the adhesive.
http://www.sandsmuseum.com/cars/elise/information/technical/autodesign.html
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You’re right 
I already ordered a bigass blowtorch.
I can get the kingpins made to a slightly larger size, then shrink fit them in. Now that would be solid…almost too solid. Good luck ever getting that out unless you got one of these suckers. 
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This has been discussed before.
A friction/chemical bond is just not 100% failproof
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Shrink fits and adhesives fail. The math can say that it will work, but as soon as you put it in the real world with exposure to outside factors everything changes. With some clever design, the extra machining may not cost any extra. But if it does, it’s worth the extra $6.
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how much extra would it be to machine the extra “slot” for a regular hex bolt?
Might be worth to make this change in the next batch?
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I know how to change the machining so it adds little to no cost. I never thought this would be an issue.
The bolt itself is whats harder because it must be made custom. A regular hex bolt with standard dimensions will have too short of a shoulder to be strong.
Also, shrink fits are known to have great reliability if done right. CNC machines utilise shrink fits to put tools in the collets. Theyre exposed to great forces.
You can use math so long as you design with a big safety factor in mind to account for the unexpected real world expectations
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Should I tug on mine or just have faith?
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Did you do the calculations using the design manual? There is a lot of factors to consider, it’s not just getting the shear resistance and multiplying by the area
I have this spreadsheet made for the torque load, but pretty easy to modify for axial load
Design Guide:
http://dm.henkel-dam.com/is/content/henkel/RetainingDesignGuidepdf
Spreadsheet:
Cálculo Retentor.xlsx (11.3 KB)
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Yes I did. My math says 40nm if torque before she gives way. Ill get my neighbors torque wrench and wrench on em.
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Instead of doing a set screw, you could use a small press fit pin going through the king pin, this way the bulk of shear will be handled by the steel, not the retaining compound
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Already going to a machine shop tomorrow to sort this out. I have a ton of 3mm dowel pins I can stick in.
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For those of you with BN hangers. Loctite and antiseize do the opposite of each other. Take your time and install cleanly and you won’t have to worry about issues. Small film of anti seize on the inside of the hanger and then bolts.
Clean the inner threads with alcohol and Q tips. Clean the bolt threads with alcohol.
Apply loc tite
Torque. I was hand tightening these to snug before and was coming up way looser than this and had no issues. I torqued to 50 inch pounds or about 4.2 ft lbs, about 5Nm.
Most of what I’ve found suggests around ± 10% 7Nm or 60 in-lb for m6 in aluminum for recommended, not max. But I’m choosing to stay lower. Those values depend on number of factors
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Why put the anti seize if you’re going to wipe away with the alcohol? Genuinely curious about this
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He cleaned the inner threads with alcohol, not the hole itself. His way is the ideal, but of course I cannot rely on people being this careful, hense the fixed axles
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Holy Christ…torque wrench settings, Q-tip colonoscopy, dowels for KP? Too funny, they’re skateboard trucks! How bout sticking w something that works and been proven to hold up, instead of “Look at how much math I know?” With all due respect, I don’t want to be Good Will Hunting just to ride my skateboard to the liquor store. The engineering concepts are great and all, and real impressive and superior, and all that. How about some basic real world stuff too? There’s a reason trucks are designed the way they have been, for a while. I hope no one gets fucked up in the experiment…
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Nothing is stopping you from buying a set of Caliber 2’s riding them for 200 miles and then replacing them because the axles bent. It’s traditional, and you can make it work for our application.
If you want peak performance, you have to go the extra mile. If you don’t, I hear that the current crop of Chinese pre-builts are decent. They will definitely get you to the liquor store and back.
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Haha…Peak performance…like what happened w my base plate, after a month? Too late, I already tried the peak performance/extra mile crap, and didn’t make it very far. Over complicating a design, doesn’t always equate to peak performance. Sometimes simple is better, and definitely better than glue, and screw in axles.
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