Gear cover screw size for HO brass locomotive

[RR_Mel]

rrebell

You are assuming it is metric, unless you have this from the factory, this is a bad asumption. Found more than a few that were retaped by former owners.

 

Agree, my thing is restoration of eBay clunker locomotives and many have been re-tapped or worse yet the wrong screw forced into a hole.

 

Re-drilling and tapping the hole normally works much better if the threads are damaged.  Having a good assortment of both SAE and Metric screws, washers and nuts is very helpful.  I have a couple of assortments from Micro Fasteners in both brass and steel.

 

Sometimes you even have to make special screws.

 

 

 

The Rivarossi screw is 2.5mm.  I was making a brass frame for a Rivarossi dual motor conversion and went with all 2mm screws.

 

 

I have a better supply of 2mm screws, as well as taps.  My steady hands sometimes don't like tapping with itty bitty taps.

 

Mel

 

Modeling the early to mid 1950s SP in HO scale since 1951

 

 

My Model Railroad   

http://melvineperry.blogspot.com/

 

Bakersfield, California

 

I'm beginning to realize that aging is not for wimps.

 

[rrebell]

You are assuming it is metric, unless you have this from the factory, this is a bad asumption. Found more than a few that were retaped by former owners.

[richg1998]

To my knowledge, all brass are imported and Metric. Get some Metric taps or tap for next USA tap. I have had to do that.

I did that quite a few years ago for USA locos.

Rich

[SeeYou190]

Tom,

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I know this is not the answer you are looking for.

.

However, when I lose a screw from one of my brass steamer (this happens way more than I am happy with), I have two courses of remedy:

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1) I go to my Northwest Shortline metric screw assortment part number 6100-5 and hope a match is in there.

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2) I drill and tap for the next largest "standard" size. In this case it would be 0-80.

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Good luck.

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-Kevin

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[tstage]

Does anyone know right off hand what screw size is normally used for the underside gear cover of an HO brass steam locomotive?  I need to replace both of them and one of the two disappeared into oblivion.  The brass company is NJ Custom Brass.

I'll be heading over to Hobbytown either later today or tomorrow with the one screw I still have and can probably figure it out from the screws they have in stock.  Using calipers, the major diameter of the screw is 0.0515".  That's smaller than 0-80 but larger than 0-90 and it doesn't seem to match any of the metric sizes either.

Any help is appreciated.

Thanks,

Tom