Member postings for Jeff Dayman

"Somehow telling me about the great steering & following it up by how many wrecks there are does not equate to a high level of confidence"

I am not aware of any Prius being in a scrapyard because of handling or steering issues. Many such cars are in use, so statistically there will be a percentage that are involved in accidents with many causes which have nothing to do with any fault of the vehicle. Many are damaged in multi car pileup accidents on major highways during morning and evening commutes, as these cars are popular with commuters due to economy. The insurance business here being what it is results in a lot of cars that could be repaired , and would have been, years ago, getting "written off" and sent to scrapyards instead.

Toyota Prius electric steering racks are highly regarded in North America as a good quality replacement steering system for vehicles with steering issues. The Prius system is compact, reliable. strong, and can be electronically adjusted for the amount of assist power, 0 to full assist (fingertip steering). Also lots around in wrecks at scrapyards, due to the vehicle's popularity. Just food for thought.

One further thought, if the rod was bent by rough handling and would normally be OK - if thread is not needed all along the rod, could you buy a die and some medium strength unthreaded steel rod and thread the ends appropriately? this may be less cost and effort than finding hard to obtain "special" threaded rod ready made.

"If I was unclear I apologise. I am replacing it because it is bent. The weight of the motor hangs on the threads, I imagined the threads on a high tensile bar would better resist being distorted."

If the motor weight is bending its' mount rod it would be wise to modify the motor suspension so it is not putting bending load on the threaded rod, only tension. If in tension only, normal low carbon steel threaded rod should be fine. If the rod sees bending load, even in high strength steel it may not be strong enough. Again, review the way the motor is suspended if possible.

Just FYI high strength and medium strength threaded rod is available in USA at McMaster.com but only in metric and UN threads. Shipping to UK or Italy may or may not be possible but certainly would be expensive.

Edited By Jeff Dayman on 30/01/2021 17:42:02

The top / darker shade is a nice colour, the locomotive will look great in it.

Your drawing has "Leading Composites" in the title block. Is this an enquiry to help a commercial firm?

Edited By Jeff Dayman on 29/01/2021 18:32:03

Before doing any machining rework, I'd suggest checking for dirt / grit jammed anywhere. it is very possible to stretch a vise thread, but grit stuck somewhere happens more often. The nut / screw may have a bunch stuck in it at one spot, or the slideways may.

You know what they say Rod - one man's 3/16" is another man's 4.76 mm....

Just kidding, that clearance will undoubtedly be handy in future, I did same sort of trimming on my mill vise some years back.

shaper and TE look great!

if you already have a boring head, that can be used as a robust and adjustable ball turner if a block is made to hold it and allow pivoting. A lever handle can be added to turn it across the work.

Many pressure tanks for domestic water supply for wells, with a jet pump, here in Canada were hot dip galvanized in and out. These were rated to 75 or 100 psi continuous service. It would be a nice option to be able to buy a hot dip galvanized heavy gauge tank or a stainless heavy gauge tank air compressor. I would gladly pay a little more for those options. As well, automatic water drain valves as use on railway locomotive air brake air tanks here would be useful, and not a lot extra. (these are just a pneumatic time delay valve that exhausts a short burst at regular intervals.)

If a hole must be reamed to an odd size there is also the homemade toolmaker's reamer, nothing but a piece of drill rod / silver steel the right dia with an angled cutting face between 10 to 15 deg ground on, then the rod is hardened.

https://www.homemadetools.net/homemade-toolmaker-s-reamer

They leave a beautifully finished truly round hole if made well, are dead simple and dirt cheap.

My suggestion would be not to waste your time with old pot metal (which was just barely up the job at the start due to the small wall thickness at the boss, and may have been cracking internally since). You will just end up with disappointment when it breaks somewhere else, maybe splitting when tapping for helicoil, or strips again if JB weld is used. The geometry looks simple enough that the part could be remade as a steel fab of a central machined block and separate arms welded or silver soldered on the sides. Or if you have machine capacity you could carve it out of one block of 6061 or 7075 aluminum. Either way you will not likely ever have an issue with it again. Do it right and do it once. Just food for thought.

Looking great! well done.

I apologize for the math error on the area calcs, I used the wrong formula.

"Say Billy, now there's a sleeve and cuff that won't fray."

5 mm OD or 3/16" OD pipe will work just as well as other sizes to pass steam of course , just as Jason said. But if the larger pipe is used the surface area is much larger which means faster/more condensation of steam until everything is warm. this means a much longer time of sputtering and spewing water when starting. 100 mm of 3 mm OD pipe has a surface area of 706 mm squared roughly, but 100 mm of 5 mm OD pipe has a surface area of 1963 mm squared roughly.

The sputtering may not matter to you at all, of course. The pipe could also be insulated with heavy cotton string secured with white glue, or silicone tube, to reduce heat loss.

I'd say 3 mm OD pipe is about right for that engine (which looks great BTW).

You might consider mating bronze flanges at each end of the pipe, with 3 or 4 screws securing them. They are easy lathe turning and drilling and can be designed with a groove to hold a small o-ring for sealing. A gasket can also be used between the flanges. If you use a short length of pipe out of the boiler with a flange soldered on it, and same out of the engine, the pipe between just needs the flanges soldered on aligned so the screws line up. Extreme accuracy is not needed usually as the pipe can be tweaked a bit to rotate the flanges a few degrees to align them if need be. Such flanges are used on full size steam plants almost exclusively, in sizes above 2" dia pipe.

For fastening, if you use bolts and nuts or studs and two nuts no tapping is required and lineup/assy is simpler.

Be sure to drill the holes accurately so that any flange fits the pattern on any other and no matching is needed.

Link below is to a video showing some model flanged pipe work and some good ideas on simple ways to make them.

https://youtu.be/gERAtP7kNxA?t=346

Not sure about your exact model but Stuart have had many changes to many of their models over the years. Like every product, changes happen over time. It is certainly more prototype-like to have split bearing blocks and caps - a real beam engine in full size from mid to late 19th century certainly would, likely secured by studs and nuts, not bolts.

looking great Ron!