What screw size was used for the Mills Escalator

[alan57]

Can any tell me the correct size of the small screw that held the Mills Coin escalator together.
There should be approx 12 small round headed slotted screws. The one I am working on only has 5!!, the rest are missing. Ive tried using a 5/32 BSW screw and its too small, and I've tried a 3/16 BSW screw that seems to be big, I don't want to force the screws and strip the thread.
I assume with the age of the machine being mid 1950's, that BSW screws were used?, there was a thread called BA, but not sure if they were used on this type of escalator.
I know one of the screws would have been countersunk, that one I have.

[JC]

At the risk of stating the obvious, Mills bandits were American - so it's pretty unlikely they would have used British threads. At a guess (and it is only a guess) I'd suggest ANC or ANF.

[alan57]

May have been an obvious answer to you JC, but up until today, I had never heard of ANC or ANF.
Thanks for the information.
Does any one have any spare ANC or ANF screws they may want to sell.

[clubconsoles]

google "fasteners & fixing suppliers" for your area, there will be a supplier in your town that will supply ANC & ANF nuts and bolts.

[treefrog]

I would love to get hold of a template for testing screw sizes and types, the amount of times I have bought expensive bags of the damn things only to find the wrong size

[alan57]

I agree with you Tom, a thread testing gauge would make life a lot more simpler

[sutton]

UNC. is American course thread. UNF. Is American fine thread.

[youngerap]

I would love to get hold of a template for testing screw sizes and types, the amount of times I have bought expensive bags of the damn things only to find the wrong size

They are out there Treefrog. For example:

[coppinpr]

you could buy a bag of each size and discard the wrong ones and it would be cheaper than that gauge

[youngerap]

I wasn't recommending it, Paul. Merely confirming that these things are out there and offering it as an example of one such product. At the other end of the scale, there is also a product costing less than £8. It is highly rated in the reviews, but looks a bit flimsy....

[coppinpr]

I wasn't hitting the idea at all, I was only commenting on that particular gauge. I know there are others out there, love the idea, just wonder how that firm can justify that price for that product.

[JC]

There are cheap pitch gauges available, although you will pay much more for decent engineers' gauges - but these should do the job:

http://www.ebay.co.uk/itm/SCREW-PITCH-T ... Swqu9U~aVS

They cover Whitworth, Metric, Unified and BA, which should cover all needs. In case there is any confusion over American National (ANC/ANF) and Unified (UNC/UNF), they are interchangeable, although there are some tolerance issues. Nonetheless, where American National were used originally, Unified should now be fine (and Unified fasteners are readily available in the UK).