Sizing small screws for ordering.

[waynecrider]

I'm repairing the GG catch latches on a Century Graphic and need to size the the holes so I can order some screws. It looks to be about 1.5mm. I think it's a size "0" SAE if I'm right. On holes this size what's the best way to measure them when your limited on space to measure. I thought a standard caliper say at Sears or Home Depot would be too large.

 

[richard ide]

One way to get close is to make a small tapered dowel out of hardwood and gently screw it into the hole. it will thread itself for a short distance. Remove and measure with calipers.

 

[greybeard]

For screws in that size range, a good vernier caliper is OK, but a micrometer is better. Assuming that you have at least one original screw, I would suggest taking it to some place like an automotive machine shop, gunsmith, or high school shop teacher and get it measured with a micrometer. The tapped holes are probably in aluminum, and may or may not be close enough for you to distinguish, say, an 0-80 (nominally 0.060 OD, but frequently a few thousandths smaller) from a 1-72 (at a theoretical 0.073 OD). Sizes 1 and up come in both coarse and fine pitch (1-64 and 1-72, for example) and these are really hard to tell apart without an optical comparator. Your best bet is to get a few of each candidate size, and figure out the pitch by trying to "mesh" them alongside a known-correct screw. You will be able to tell easily if the pitches match, but you will still have to verify the diameter, since the same pitches occur in both coarse and fine thread series. (Fortunately, you probably don't have to worry about metrics creeping into the problem...)

 

[waynecrider]

Well I went to a hobby shop that had screws in a size that would work. They kept them over the the railroad section. Unfortunately no nuts to go along with them so I'm gonna drill flat stock and tap it. I did get a caliper for $20 thats pretty nice for the money. Measures the 1/16 hole with no problems.

 

[DBP]

I've been lucky in that my little neighborhood hardware store carries a surprising variety of tiny screws, along with other things that are hard to find in bigger stores. So I have walked in there with some pretty odd requests.

 

[John Shriver]

I got wonderful brass wood screws for my Pony Premo #4 at boltdepot.com. Things like #1 x 1/4" oval head brass screws! Quite the selection, plenty of machine screws, too.

 

[Curt]

Are you taking about screws or bolts? Bolts can be very tiny also.

 

[Charles Webb]

Our local ACE Hardware has an excellent stock of tiny screws etc. Canon City is not a very big place so I believe if our ACE has them most likely they all will carry a similar stock.

 

[freygr]

There are allot of online stores that carry the small hardware, a few links: http://www.micromark.com/, http://www.smallparts.com/, http://www.nutty.com/, and two unlikely sources http://www.mcmaster.com/ and https://www.mscdirect.com/ of which McMaster-Carr has a better selection. But support you local hardware store as the big box store will not carry the stuff which doesn't move.