Alternative to M5x30 for Primo build

I’m in the US. Hardware stores for nuts/bolts/screws here are so much cheaper than buying online. There are 65 M5x30 screws (and locknuts) required for my Primo build (reusing most items from Burly). My issue is that the closest size to the M5 is a #10-32, but the nut that fits in the nut slot (8mm across flats) is the #6-32 nut or mayyybe the #8-32 nut. To get the #10 nut in those spaces, I’d probably resort to using an old soldering iron to push them into the nut slots. That seems like a lot of work, but will also give the best results (already printed the parts otherwise I’d probably just edit the nut slot size in solidworks). Should I go #6-32 which definitely works, but is probably too small, a #8-32 which barely works and is maybe a bit too small or #10-32 which works for the screw but requires a heated nut insertion (so to speak)? These are metal screws holding together plastic parts so I really don’t know.

Any help/advice would be appreciated!

You need the 5 mm for the roller guide bearings(iddler) for the belt I just ordered them to head off problem

If you’re upgrading a burly, why not pick up an upgrade bundle from the shop? Has all the hardware.

Second best solution is to order stuff from bolt depot. I find that sometimes their bags of 100 are cheaper than ordering 50. Downside is you end up with some extras.

I’d put using nonspec hardware at a distant third place, especially if you have to mash things in with a soldering iron or come up with some clever way to hold nuts in place. The price difference can’t possibly be worth the extra time, hassle, and extra variable when you ultimately have to troubleshoot this machine. But YMMV.

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C. F. Bennett. The name you’re looking for is C. F. Bennett.

Thanks for the comment. Bolt Depot actually looks promising (I’d assumed shipping would kill any online orders, and didn’t really check outside Amazon) and having extras at that bulk price is actually a plus to me rather than a downside. I actually had all of the hardware from other various projects other than the M5 screws (because I could usually get away with using #10 screws instead). Thanks for the advice. Will def take it into consideration!

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At least 8 of those have to be 5mm. For a #6 or #8 you might get away with printing a sleeve for the idler bearings, but I don’t know I’d want to depend on that. Maybe if you have your 3D printer dialled in really well.

For size, I wouldn’t be too concerned. Considering how many warnings there are not to overtorque anything on assembly, I’m sure that a #6 screw is more than strong enough.

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Thanks for the Bolt Depot tip. Build the burly using locally sourced (Ace, True Value) stores. But always had to chase around to find everything. Just ordered everything for a LR2 for 1/2 of what I was expecting to pay!

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+1 for bolt depot. I got these a couple weeks ago after finding Amazon was sorely lacking. Now I’ll never run out.

Now I just need to figure out what to do with all my #6-32.

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Seriously, I absolutely love that place. I found myself short on a handful of bolts because I f’d up my order. Tried to get them from Amazon, and after a week they said ‘not available, well let you know when they ship’. Waited another week. Tried home depot online order, got to the store, not what I ordered. Waited a couple more days. Gave up and ordered them from BD (I was trying to avoid the shipping at that point). They still showed up before Amazon shipped (which they wouldn’t let me cancel, so I had to return them).

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My order came Friday. Wow, impressed as well. As Jamie’s picture shows, everything is bagged and labeled. No more chasing around to 5 different hardware stores and paying 30 cents for a 2" bolt :slight_smile:

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Had the same problem/question - so really appreciate this topic and the recommendation for Bolt Depot. Now it’s time to return #10-24 screws/locknuts to Lowes and Menards…

I hope the new locknuts fit into the cavities - otherwise I may also consider pressing them in with a soldering iron-

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