My A3 Progress

[ramkitty]

I recently received the A3 switcher book and after several hours of slowly flicking through the pages I am getting ready to start. One observation (noted before) is that there is a lack of a bill of materials. A BOM would be nice but what I am more concerned about is the fasteners.

What tiny brass screws will I be requiring throughout the project and where would be a good place to purchase these. I have no local stores that stock #0, 3, etc in brass. Also looking through the book I see round head machine screws specified but in the pictures I may see a hex head. Were these used to be more correct.

Finally in the beginning of the book loctite 75 retaining compound is mentioned. The only similar part I could find (online) is loctite 675 and it seems to be only available in 250ml (very costly) what is a suitable replacement.

[GregMiller]

Here is a link a thread on Loctite

livesteam.proboards.com/index.cgi?board=kozo&action=display&thread=663

I have not found a single source for ALL of the fasteners. I use www.SmallParts.com for most of the small fasteners, www.McMaster.com also has some and www.americanmodeleng.com has the Hex head fasteners. I also like the taps that www.americanmodeleng.com sells for the 0-80 thru 3-48.

Welcome to the build, Have Fun!
Greg

[ramkitty]

In cleaning my work shop I found a 3x3' piece of copper. I got excited since it looked close to the .040 for the tender. Sadly It is 20 oz .027

[dickr]

Careful what you say, might get your hand slapped. Wanting a (BOM)! The materials will nickel and dime you to death. It'd be time well spent to go through the book just to get a majority list of the materials and order. Then you don't have to stop all the time to get the little pieces needed. My humble opinion is that most any of the liquid fasteners at a hardware store will work pretty well. MSC, Travers, Rutland, etc. (tool supply houses) offer them in small tubes. I have used 4-40 screws in 90/95 % of all 3-48 call outs. They are much more common including the tap and die. You can easily see if it will work or not. The same goes for the other oddball threads called for.
Have fun and do it your way !!!

dickr

[pkastagehand]

I think there are some #1-64 screws called for at times. They seem to be hard to find. I used #1-72. I also have used American Model Engineering Supply (see link above) for most.

Most of what I see in the hardware stores is thread locker and I'm not sure it would be what is wanted for wheels, etc. I suggest getting 675 or 609 as mentioned in the thread linked to above or equivalent. Not to start any arguments but not all liquid fastener materials are created equal...

Also, the key word in using liquid fasteners is CLEAN. Get all the oils, etc off the materials and that includes your skin oils. Don't touch a surface to be "glued" with your bare fingers after cleaning.

My $1.02 (2 cents plus inflation)

If you build it in brass and copper like the book says it will be more expensive than just nickels and dimes. But there is no way I wanted to chunk out the bills all at once, so even if I had a BOM right from the start I would probably have still bought in bits and pieces as needed. Yes, that has slowed me down. There have been a lot of times that I could not finish something because I needed materials. But if you skip around in the book you can often switch to something else you have materials for while waiting for an order.

Except for the bushing bronze and the copper and brass for the water tank on the tender I've built it all so far out of steel and cast iron, much of which was on hand or found/scrounged. Assuming I do a copper boiler that will be the biggest single metal purchase for me. I am thinking of doing it in steel with copper flues. At least one other I know of has been made from steel.

Paul

[ramkitty]

I ordered some stock and while waiting I finished the first parts. I made 10 springs from 3 pieces of 039 music wire. After grinding one was somehow too short but 9 are great. One set of parts down only about 10000 more, I should be done by 2040. ;D

strong little suckers too... probably supports up to 10 lbs.

I should also add that this is really the first time I have made something on a metal lathe although I know a bit about how the lathe and milling machine work. Next up is the bending jig for the arch bars

[kenrinc]

When I started the project I was one of those who felt a BOM would be helpful too but now I'm not so sure. It's easy enough to go though each section and get a "ballpark" as to what is needed. And some of Kozo's choices were odd as far as material sizes. Some I couldn't find and had to mill from larger pieces. Not a big deal but it does show you that even with a BOM people would be pissing a moaning that it's not correct. As Paul pointed out, most would not be able to afford to buy based on a brass/copper BOM, especially right now. I go though each section and one section ahead and buy what I think I need and then move on. I'm building 1.5" scale all steel/iron.

Ken

[grege]

As I was getting started I made up my own materials list.
I went through the whole book part by part noting material and approximate size needed including some machining allowances where needed.
I combined it all into a spreadsheet that I've been using to make purchases.
I found as I ordered things that there were several times it was cheaper to get a longer piece of larger material than two or three sizes.

I think it's helpful to do this work on your own to gain familiarity with all the parts and materials. Your own preferences will govern on whether to buy all sizes noted or to cut down from larger material.

[pkastagehand]

Jun 4, 2010 13:10:39 GMT -5 kenrinc said:

... And some of Kozo's choices were odd as far as material sizes. Some I couldn't find and had to mill from larger pieces. ...

Ken

I think because he was working maybe in metric materials over there some of the things come out to odd sizes. The boiler for example. McMaster-Carr does list copper in a thickness that is pretty much what is called for in the book but I think maybe it is 2mm sheet that they have given a fractional inch size name to, because other places I've tried say there is not a size that is .079" thick.

And I have done as others mentioned. Put info in a spreadsheet one section or so at a time.

You'll probably work out a method that works for you as you go along.

Paul

[ramkitty]

Thanks for the info guys. Today I made the drawbar pin from scrap == free ;D that wont happen very much I think. I made it using the tailstock and there is a little bit of a taper over the length. 4thou or 2 thou on the lathe (both sides of the cut) is this caused by misalignment of the tailstock. If so what is the best way to fix it.

As such the pin is slightly under sized at around 155 thou but I dont think it will matter for what it does. I got the head is right on using the chinese import micrometer I have. It looks pretty too.

I had made it by turning a distance down to size then pushing the face flat and to length. I am sure there is a better way.

I am also not sure how to precisely measure the length of the pin using the depth gauge of the caliper I can measure it but it doesnt seem to be the most precise method. I measure 1.121 so i am short 4 thou.

Finally kozo suggests using a broken hacksaw blade as a thin parting tool, how is this held while cutting? I was thinking about starting the center pins for the tender trucks and I am stuck on how to machine the e-clip grooves.

[grege]

Fixing a misalignment of your tailstock depends a bit on your lathe.
Here is one I found recently on the Chaski board -http://www.chaski.org/homemachinist/index.php:
www.frets.com/HomeShopTech/QuickTricks/TailstockAlignment/tailstockalignment.html
This fix assumes your headstock is parallel to the ways and the tailstock height matches the spindle. I'd recommend a search on Chaski- much more info than I could come up with...

I hold hacksaw blade pieces in a parting tool holder for my QCTP that accommodates varying height blades. I have a couple ground thinner to suit the various e-clip sizes.

Greg

[trainlarry]

Ramkitty,
You said that there is a taper in the drawbar pin you turned and you suspect the tailstock is misaligned. Did you drill a center in the end of the pin, and hold the pin in place with a dead center in the tailstock? Did you use the compound (tool) rest to turn the piece, or did you just move the saddle? The reason for the questions are that a misaligned tool rest can turn taper also, not just a misaligned tailstock. You may have one, or both problems, and the misalignment must be found and corrected, or you will never make good parts.
Before you check the tailstock, check the toolrest for proper alignment. Chuck a 6-8" length of drillrod, as large a diameter that you have. Mount a dial indicator on the toolrest, and crank it all the way towards the chuck. Move the indicator to touch the bar close to the chuck and set to zero. Lock the saddle and cross slide. Now crank the toolrest out and watch the indicator dial. If it moves,
the toolrest is in need of alignment. Loosen the bolts and tap it a bit
to get the needle close to zero. Tighten the bolts, re-zero the indicator, and sweep the bar again. Continue the procedure until the dial indicator shows no movement throughout the range of the toolrest as you sweep the bar from one end to the other.
Here is a good read on how to check and align the tailstock, taking into consideration the assumptions Greg made are valid:
www.cartertools.com/tgtest.html
Check your lathe, and let us know what you find.
(A side note: cheap live centers are not accurate, and will cause you to turn taper, even though the tailstock and toolrest are accurately aligned.)

Larry

[ramkitty]

I center drilled and used a cheap live center.. I have some dead centers but thought the bearing model would be better to use. I used the power feed on the carriage and did not use the compound because I did not true it. I set it by eye locked it down and used the cross feed and carriage. I only used the compound to feed into a facing cut.

[trainlarry]

Ramkitty,

More than likely your live center is the cause of your tapered part. My asian-made live center ran .004" out of true and caused my parts to come out tapered until I found out why. I now use only a dead center and have no more problems. I also checked the alignment of the tailstock and compound to make sure everything is square.
Keep us posted on your progress.

Larry

[ramkitty]

I tried 2 dead centers and can not get any better than 1thou runout on either side. I cant seem to get the headstock to be true. the plate measures 2thou on the face and the deadstock in the taper is maybe 3/4 thou.

On the upside the deadcenter and live center in the tailstock both read the same.