Accucraft freight car Guys, I own every size of nut driver known to man, WIHA tools, both metric and inch. This is smaller than 3/32 and bigger than 2 MM, but smaller than the next 2.5 MM. AFAIK, there just aren’t any available sizes in between in nut drivers. j
John:
I’ll go out and measure one of mine, but it is probably 2.2mm. The 2.2mm is a standard, but not very common. It is not included in most sets.
Here is a link to a single bit:
http://www.micro-tools.com/store/item_detail.aspx?itemCode=49-8074
Hope this helps.
Happy RRing,
Jerry
I just noticed that the 2.2mm driver above is a special order at Micro Tools. They say up to two weeks to get it.
Here is another one that they show in stock:
http://www.micro-tools.com/store/item_detail.aspx?itemCode=51-2481
I believe 2.2mm is commonly used on eye glasses, so an eyewear provider might have the hex driver.
On Edit:
Yep, eyeglasses: These guys show a more expensive one, assumedly in stock:
http://qtena.com/22mm-star-driver-eyeglass-wrench-rimless-eyeglasses-fits-22mm-nuts-p-4900.html
Happy RRing,
Jerry
Jerry,
Thank you.
I thought I owned all the sizes. Guess not. 
Neat website.
I’ll order it!
John:
I just measured a couple of my (early-first run) Accucraft boxcars, and the same bolts measure ~2.01 to 2.02mm (definitely not 2.2mm) across the flat. Kind of hard to get an accurate measure, as they are painted. I loaned my metric set to a neighbor a couple of days ago, so can’t try them.
In comparing mine with your pix, I would say yours appear to be bigger. I also don’t have a 2.2mm driver, so can’t be certain.
Be sure to read my edits in the above replies.
BTW, there is always one more tool that we don’t have, but definitely need. At least that is what my wife says.
Happy RRing,
Jerry
I betcha a pound to a pinch of parrot poop that they are BA [British Association] - a range of modelling size threads and hexagonal bolt head standards that goes from 0 BA [biggest] to 16BA [smallest practical size for human fingers]. Here in UK they are extensively used in model engineering as you can buy ‘next size down’ hexagon-headed bolts for scale-size fixings on your models.
Remember that the part of China where these models are made WAS held by the British for 100 years.
I could, however, be wrong.
tac
www.ovgrs.org
John Bouck said:a. I bet ya don't. Got BA? Got BSC?
a. I own every size of nut driver known to man, WIHA tools, both metric and inch. b. AFAIK, there just aren't any available sizes in between in nut drivers.
b. Yes, there are - see my post.
That’s how I took my AccuCraft Hudson to pieces last week.
But that, as they say, is another story…
tac
www.ovgrs.org
Yuh caught me red handed, TAC!
I only own 3/32 in 64ths up to 1/4 and hence to 1/2 in 16ths.
I think my metrics go 1.5 thru 6, less the freakin 2.2!!!
If I can get the bolts out, I will retap to size 0-80 and use the 3/32 hex machine bolts I have in stock.
TAC,
YOu own some accu, don’t you?
Find out the British size and send me one.
Dear Mr. Ho.
1.6 mm is way too small!
Please try again.
http://www.accucraft.com/index.php?productID=98
Or do you think this is some odd-ball named size, like TACs?
<<Dear Sir,
Thank you for your inquiry. Please note hex head screw size is 1.6mm on all freight cars for outside brake assembly. We have in stock hex head screw driver in this size, part number AP29102, with retail at $9.00 each should you require it. Please let me know if I can be of any further assistance.
Best regards,
Ada Ho
Product Manager
American Model Supply (AMS)
Division of Accucraft Trains>>
John:
Interesting that Accucraft can’t come any closer than that! As one of my Asian friends is fond of saying, “We do not have clue.”
Mine are pretty definitely 2mm, but as I wrote above, the ones in your picture appear to be slightly bigger. That, along with your report that the 2.0mm driver is too small and the 2.5mm is too big, makes me reasonably certain they are 2.2mm.
TAC’s suggestion about the BA Standard / Asian metric standards cross over is historically correct, but this is newly engineered stuff. I think it would be accidental that a BA driver would work on modern Asian stuff.
Happy RRing,
Jerry
I’ll see what I can do. Whinemeal, I’ve ordered you a little set of the proper spanners in good quality - they should be here in a day or so.
Price is a very reasonable $945.75, plus $80-75 shipping and handling.
Only kidding.
E-mail or PM me your real addy - I promise I won’t tell the feds 
tac
www.ovgrs.org
TAC & Jerry?
Do you think Chinese 1.6M (per Mr. Ho) is the same as 2.2MM?
TAC,
Hang on to it while I deal with Mr. Ho.
I haven’t bothered to check any of my other Accu cars yet.
Maybe they are randomly sized from 1.6 to 2.2…
Wouldn’t suprize me at all.
John:
On re-reading Mr. Ho’s missive, I now believe he is indicating that the size of the screw body is 1.6mm diameter. The wrench sizes are specified by the across the flat dimension of the hex head. A 1.6mm diameter screw could have an across the flat dimension of 2.2mm for the hex head.
I’ll be going out to my shop later today and will try to find the head dimension for a 1.6mm diameter screw, but I do think his driver will fit. Try asking if Mr. Ho knows the across the flat (AF) dimension for the driver to be certain.
Happy RRing,
Jerry
I have posted this tip before , in another life .
Get some brass hex tube , several sizes . If it is slightly too small to use as a tube spanner , a gentle tap whilst holding it over the nut deforms the brass to make it fit . Do not try this on 2" nuts .
This is not a joke , and it gives an infinite variety of sized spanners----------cheeeeeeeeeeeeeep .
Mike M , Ingenieur Extraordinaire . Or perhaps just extraordinaire .
edit----- some well known US company makes this stuff , you probably don’t even give a passing glance at the tall red box in your local model emporium . It’s by KS , and holds a variety of useful brass and aluminium . The great thing is , the round and square and hex toob are an exact fit inside each other . You have to get different sizes for that to work .
Great for simulated hydraulics .
19:27 local
John Bouck said:
TAC & Jerry? Do you think Chinese 1.6M (per Mr. Ho) is the same as 2.2MM?TAC,
Hang on to it while I deal with Mr. Ho.
My pal Dzhon here says he’ll have them instead. They’re only $7.50 for set of five, after all.
tac
www.ovgrs.org
I forgot to mention ----if the brass starts to deform as you try undoing the bolt , slide a next size up hex tube over the first , or even a second one too , and so on .
Note that this can produce a 1" o/d spanner . Not good .
Mike M
Update:
It turns out they are 2.2 after all.
Dear John,
Thank you for the prompt reply as I apologize for the incorrect information. Please retract previous statement, as hex head is 2.2mm with screw thread diameter at 1.6mm. I’ve reconfirmed that our hex head screw driver AP29102 mount to hex head screws on outside brake assembly. There are two hex head screws that we generally use on all Accucraft, AMS, and AML products: AP29101 (2mm thread diameter with 3mm head) and AP29102 (1.6mm thread diameter with 2.2mm head). Please let me know if I can be of any further assistance.
Best regards,
Ada Ho
Product Manager
American Model Supply (AMS)
Division of Accucraft Trains
I guess that answers the question on what the small heads are on my Accu Shay. The sent the 3MM nut driver with the engine, but not the 2.2.
Thanks for doing the research.
John Bouck said:
Update: It turns out they are 2.2 after all.Dear John,
Thank you for the prompt reply as I apologize for the incorrect information. Please retract previous statement, as hex head is 2.2mm with screw thread diameter at 1.6mm. I’ve reconfirmed that our hex head screw driver AP29102 mount to hex head screws on outside brake assembly. There are two hex head screws that we generally use on all Accucraft, AMS, and AML products: AP29101 (2mm thread diameter with 3mm head) and AP29102 (1.6mm thread diameter with 2.2mm head). Please let me know if I can be of any further assistance.Best regards,
Ada Ho
Product Manager
American Model Supply (AMS)
Division of Accucraft Trains
Are you replacing the original freight car wheels with the new filleted wheels? Did you get them from Electric Model Works with the electrical contacts? Are they the same diameter as the originals? An inquiring mind (what mind I have left) wants to know!
I just wish they were less than $36 / car!
Happy RRing,
Jerry