Hints and Wrinkles
Below are some hopefully helpful tips etc. for making various jobs a bit quicker and easier. I don't claim any originality for the ideas as I've probably picked them up from Model engineer etc.
Rather than keep a large stock of different sizes, just buy the longest lengths of each thread size/head type and cut to length as required. The difference in price between 1/4" long and 1" long is not great and you're probably going to have to cut bolts to non standard lengths anyway. The cut off bits are always useful for making studs. I always buy bolts with the one size smaller head if possible so that they don't look so far out of scale.
To make the job easier, especially if you've a lot to cut to the same length, make a simple jig. Get a piece of scrap flat bar the same thickness as the length of thread that you want and drill a clearance hole in it to suit the diameter of the bolt. To use just clamp the bar in the vice, push the long bolt through the hole, hold it in place with a file handle or similar, and cut the protruding length of thread off with a small saw leaving the end slightly proud of the bar. Then just file the end flush with the bar. Remove the bolt and chamfer the end of the thread to remove burrs with a needle file. To make it easier to hold the bolt when doing this, put the bolt in a box spanner held between finger and thumb with the threaded part resting against the finger. It's an easy job then to file the end and turn the bolt round at the same time. Result - bolts all exactly the same length which looks a lot neater on the finished job.
To make the jigs last longer they could be case hardened or made from a piece of silver steel bar or gauge plate and hardened right out.
When threading holes in frames etc. make a simple guide to make sure the tap is vertical to the metal. Get a piece of steel flat say 3/8" thick and drill a clearance hole for the tap vertically through it. In use, hold the bar against the metal to be threaded and insert the tap through the hole in the bar and tap the thread. It also pays to use proper tapping compound rather than ordinary oil which is not as effective. Using the guide and the proper lubricant should result in fewer broken taps!
For marking out small components use a broad tip permanent marker pen as an alternative to marking out fluid. Quick and easy to use.
Machining duplicated components
When you have two or more identical components to make such as bogie frames etc, it's useful to clamp or solder them all together and machine them as one piece. That way they will come out identical and only one set of machining operations are needed instead of two or more. This is the standard way to produce loco mainframes. I used this method to produce the four bogie frames for Helen Longish and the four bogie equaliser beams.
With items such as frames it's easy to just drill a few strategically placed holes and use copper rivets to hold everything together but it's not so simple if the finished components don't have any suitable holes in them, like the bogie equaliser beams. In this case I solder them together using Carrs 188 solder paste which gives a strong enough bond in most cases. Just clean the faces to be joined, coat one of the faces with the solder paste, clamp the pieces together and heat until the solder melts. I usually do this over the domestic gas ring as not much heat is required. After machining etc, just reheat to seperate the parts and clean off the solder.
Milling long cuts using the topslide etc.
I sometimes find it difficult to keep a steady continuous feed when milling a long cut using the vertical slide or topslide. The normal Myford leadscrew handles are very short and it's hard to turn them at a nice steady rate especially if, like me, you keep the gib strips on the slides a bit on the tight side to reduce chatter. I remember reading an article by Keith Wilson (I think) in ME where he described fitting extended handles to the leadscrews to overcome this problem. I was doing some milling the other day and adapted this idea by simply using a spanner on the flats of the micrometer dial and using the spanner to turn the leadscrew. This made a makeshift long handle which made it very easy to get a steady feed. I will get around to making something more permanent in the future though!
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