Large Scale Central

Converting Bachman Fn3 cars to Accucraft Couplers

Modeling Rolling stock
#1

I’ve never been happy with the new Bachman Fn3 metal couplers. They look good but don’t operate very well. They take quite a hefty bang to get the pin to drop, and when uncoupling they don’t want to come apart. In short, they just aren’t suitable for use on an operating railroad. I’ve always liked the look of the Accucraft couplers, so when John Bouck siad he had a bunch available for trade, we started talking. The couplers John has are removed from Accucraft rolling stock, so they don’t have any draft gear - just the coupler head with a short shank. After a bit of discussion, John said that he also had some spare Kadee draft gear boxes. Recently he sent me a sample of what he had available for barter…

The box with the shank in this photo is a Kadee 831. John also sent some of the larger Kadee 830 boxes along with a few Bachman Fn3 couplers for me to check out. After looking at the combination of items John had sent, and what I had to convert, I decided that the Bachman Fn3 stock was ripe for the upgrade. Unfortunately, none of the combinations that John sent (except for the Bachman couplers) were a direct retro-fit to the Bachman Fn3 cars. Then I remembered what John himself said when discussing couplers in a post a few weeks ago…

John Bouck said:
Drill new holes and make a shim. Do what it takes to make the model to your specifications.

Well, it took just a bit more than that, but using only the parts John sent, I was able to come up with a solution to mount for the Accucraft couplers to the Bachman cars. When I looked at the stock coupler mount on the Bachman cars, their “gear box” is almost identical to the Kadeee 830. The screw holes line up exactly. So, the task at hand was to get the Accucraft coupler to fit into the Kaydee 830 box. Since the shank on the Accucraft was to short to reach into the post in the 830, I considered using both the 830 and 831 together. First, I enlarged the hole in the Kaydee 831 mount to 1/4" to match the post in the 830 mount… [url=lsc.cvsry.com/AccCoupler01-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] When I test fit the 831 inside the 830, it was too thick. The gear box cover was not going to close. So I milled off some of the shank using my Dremel and a sharp knife… [url=lsc.cvsry.com/AccCoupler02-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] [url=lsc.cvsry.com/AccCoupler03-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] [url=lsc.cvsry.com/AccCoupler04-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] Now the shank will sit down on the post properly at the shank end, but not at the coupler end. So the 830 needed a little trim as well. A little of the end please… [url=lsc.cvsry.com/AccCoupler05-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] [url=lsc.cvsry.com/AccCoupler06-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] Then some off the top… [url=lsc.cvsry.com/AccCoupler07-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] Before and After… [url=lsc.cvsry.com/AccCoupler08-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] Now the 831 will fit inside the 830 box. At this point of the assembly I didn’t realize that I had the coupler upside down. My fix was to just flip the 831 over, but you will see in the later photos that flipping the 831 screws up the alignment. A better fix would be to flip the coupler in the 831. [url=lsc.cvsry.com/AccCoupler09-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] [url=lsc.cvsry.com/AccCoupler10-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] Side-by-side with the Bachman Fn3 coupler & gear box. [url=lsc.cvsry.com/AccCoupler11-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] With the 831 flipped over. Note that the 831 no longer is square with the 830 box. [url=lsc.cvsry.com/AccCoupler12-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] [url=lsc.cvsry.com/AccCoupler13-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] Finally, here is the new combined Accucraft coupler + Kadee 830 + Kadee 831 mounted back on the Bachman Fn3 flat… [url=lsc.cvsry.com/AccCoupler14-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] [url=lsc.cvsry.com/AccCoupler15-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] Back over on the track, under fluorescent lights the colors are a bit screwed up, but you can see that without any shims, the modified Accucraft coplers line up with and couple to the Bachman Fn3 couplers… [url=lsc.cvsry.com/AccCoupler16-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] [url=lsc.cvsry.com/AccCoupler17-1280.JPG]

[/url][color=blue]FF: Click to Enlarge - IE: Right Click Photo and select Open Link in New Window to Enlarge[/color] This looks like a lot of parts and fooling around. Parts wise, since I’m paying with barter, that’s not a problem for me. If buying couplers you might want to buy a different style draft gear box rather than go through all this. On the plus side, this modified coupler mount uses the exact same screws and screw holes as the factory coupler, so it’s very easy to go back to stock. As far as labor goes, it took longer to take the pictures, upload them and type up this post than it did to install the coupler :smiley:

#2

Jon,

Great macro shots. Camera / photo details, please?

Thanks.

Sincerely,

Joe Satnik

#3

Good job!
Phun, eh?
Try using a Bachmann 830 gear box, as well.
KD 830 gear boxes are rare around here.

What’s the tightest radii they will operate on?
I can’t get my Bach to make a 6’ dia on my indoor layout, the wheels rub the coupler.–prolly fixable with a dremel. (Out side I have 18’ + no problemo).
Accu’s with KD’s go around with ease on the 6’ radii.

#4
John Bouck said:
Good job! Phun, eh? Try using a Bachmann 830 gear box, as well. KD 830 gear boxes are rare around here.
Yes, I'm pretty sure the same result could be had by cutting the Bachman gear box. I'll check that out.

The one drawback to this method is that the coupler ends up about an 1/8" or so further away from the end beam. I decided that I was willing to accept that since it was much easier to enlarge the existing hole on the 831 than to relocate it. There is a dimple, forward of the screw hole that might work, but the the gear box would need to be cut deeper. As I have it now, the cut is right along a molded in edge.

#5

Put a small chain back on the coupler and the lift bar on the car and see if it works.

#6

Joe -

Thanks. I was actually thinking they are a bit large for the subject matter, but I was too lazy to crop them down.

The camera is my older digital. A Fuji S700Zoom. It has two built-in macro settings and has always done a nice job with them using auto-focus / exposure. I recently relegated it to eBay photo duty so it lives in the basement on a tripod set to low resolution (1280x960).

I think the key to good macro photography (besides camera/lens) is having a good location and two-point lighting. My picture taking location is just the inside of a large cabinet that I lined with gray paper curving the corners. Lighting comes from two incandescent spot lamp bulbs - one in a goose neck desk lamp, the other in a hinged desk lamp. This allows positioning them to get the best fill light and lack of shadows. The camera has a manual white balance that I set using a white card illuminated by the incandescent lamps.

I also have a Cannon Rebel XTI, but the combination wide/zoom lens I have doesn’t get as close or as sharp in macro conditions. I sure do love the Cannon for outdoor work though :smiley:

#7
John Bouck said:
Put a small chain back on the coupler and the lift bar on the car and see if it works.
OK I'll try that. Hopefully I didn't break the cut lever mounts. When I was messing around taking the BMan coupler of the cut lever pulled off one end.

I’m also going to flip the Accu coupler over so I can get everything square again.

#8

Hey,
I’ve been caught with an upside down KD a time or two as well.
A friend would point out the “air line” was sticking up, instead of down. :slight_smile: :slight_smile:

#9

John - I can’t keep up with your edits :slight_smile:

Re Curves - The Bachman cars make it around my balloon track and through the wide switches I have indoors. I think the balloon has some 8 Ft. Dia. curves in it, but about half is hand bent and I’ve never measured it. My next smaller size indoors is R1 switches in the yard. NONE of my Fn3 stock except the Dizzy is allowed in that area of the yard.

Big curves indoors is problematic :smiley: Outdoors I try and stay with 10 Ft. Dia. Minimum but might have a spot or two that is a little tighter.