#8-32 bolt fit in a 4.5mm hole?

Status
Not open for further replies.
Moderator
Joined 2002
Paid Member
Well, will it? The business of selecting the right bolts has me going nuts. I ordered a set of 8-32 bolts and now am getting worried they won't fit the 4.5mm holes (actually, 4.3mm) on my Seas drivers.

Which means I'm about 40 bucks down on hardware on a $300 project (already bought a lot of incorrect sizes locally).

So, will they fit? at 0.164" it works out to 4.1mm, but that's not much of a margin, really.
 
Bolts and hurricane nuts on the baffle 🙂 If my woodworker can make the landing zone correctly after doing the chamfer at the back, that is. Else set screws, but surely trying to avoid it like the plague as I know how painful those can be.

Thanks for the reply, Andrew. Measured the bolts that are being used now (they fit the driver holes perfectly) those were around 3.5mm (size 6 I guess), so was not able to work this out in my head and frustratingly, there isn't a single chart I could find that converted this to the millimeter scale that all driver specs seem to use.
 
Your holes of 4.3mm (~0.169") are a tad smaller than the recommended 8-32 clearance hole size of 0.173" but you can probably get away with it. Is there any reason that you couldn't simply enlarge them? M4 bolts would have worked as well.

I think a table of tap and clearance drill sizes is indispensable for mechanical work.

Here's a decent one: http://www.physics.harvard.edu/services/machineshop/shoplinks/THREADCHART.pdf

Also, you're not likely to find a chart that gives specs for Imperial thread sizes in Metric units.
 
Last edited:
any really useful chart will always specify the diameter in both imperial and metric dimensions.

I have a glossy printed one hanging above my lathe.

It has letter/number code, inch size, fractional inch size, metric size.
Absolutely indispensable when one is looking for tapping sizes and clearance sizes and near equivalents.
 
I'm not keen on putting a hole in the rubber surround. My hands are terrible for delicate mechanical work and I have no test box to properly secure the driver.

I checked the bolts through the holes and they seem fine to me, though, so I guess I'm just about safe.

Tosh, thanks for the reply - I must've not been able to track it during the changeover to the new boards, but yes, that page seems somewhat useful. 🙂
 
Status
Not open for further replies.