Member postings for Paul Lousick

3/4 of my work is done on a mill and trying to do this on a lathe with a mill attachment would take twice as long or would not be possible. My advice is to get the mill.

Best of luck with your model.

Paul.

Extract from Australian model code for boilers. (max. pressure for models is 100 psi)

Tin melts at 232 °C (450 °F) ,    Lead melts at 327.5 °C (621.5 °F)

Paul.

Edited By Paul Lousick on 15/04/2015 13:19:45

I had to cut a 100mm dia hole in 10mm plate and used a 25mm Rota broach to step drill a series of holes to the rough shape for the hole. Then bored the hole to the finished size.

Paul.

Hi Nick,

I am building a welded steel boiler and am not familiar with silver soldering copper. Ask the question on http://www.tractiontalkforum.com in the model section. There are a couple of people from Oz who are building copper boilers. They should know what to use.

Paul.

Edited By Paul Lousick on 03/04/2015 07:32:30

Hi David,

Make sure that the tilting vice which you buy has a good locking arrangement for the tilt. I have a similar one which can move under heavy loads.

Paul.

I already have a smaller version of the machine in the video. I call it "shovel" and used it to transplant this "weed".

Hi Chris,

The bolts/rivet have a nut which is tightened.

I have changed the design for attaching the hornplates on my Ruston to comply with the details shown on the Aus. code. Our codeshows the hornplates attached to the bottom of the boiler (under the fire grate) and to a mounting plate in the upper side of the boiler. My inspector queried the original design and I decided not to cause any problems and change the design.

Paul.

Thanks for the comments.

Michael G, No the square holes do not have to be completely square. I am bolting the hornplates of my traction engine to the boiler and want the head of the bolt to look like a round head rivet. To stop them turning, I am making the end of the bolt near the round head a square shape, similar to the square on a coach bolt (if that makes sense).

Michael C. The rotary broaching in the mill idea looks promising. Will give it a go.

Thanks everyone, Paul

My copy of the March MEW arrived today. I live in Sydney and normally receive it about the middle of the month. The newsagents get it about a week earlier. Problem is that they do not always have it in stock or have sold out.

I still get a regular delivery of the magazine, Just 2 weeks after it is released. No problem,

Paul.

I would like a push broach but still expensive which is why I asked if anyone had made one.

Laser cutting is not an option as I already have the profiled plate. Just needs the holes.

Regards, Paul.

I need to cut a number of 10mm square holes in 6mm MS plate (about 20) and the cost of a rotary broach is too expensive.

Has anyone made their own square push broach ?

Was also thinking of drilling a 10mm hole first then using a rotary broach tip held in a guide to punch the square holes with a press.

Paul.

My copy normally arrives about a week or so after the issue date but it appears in the newsagents much earlier.

Paul.

Hi Tom

S/S is harder to cut than mild steel. Cutters tend to rub the surface and not cut if not sharp enough.. Check that it is 3mm dia and not larger. Try adding a taper to the end of the rod, not just a small chamfer.

Paul.

Mine is a work horse not a show pony but try to keep it reasonably clean and well oiled.

Hi Nick,

I had a similar problem with the traction engine which I am building. The drawings are imperial but I decided to work in metric because I already had a lot of metric tooling and I normally work in metres in my job. (easier than using fractions). You should also consider what size of material is available for making your model. Many have been changed to metric. The biggest problem I had was finding pipe to make my boiler barrel. The drawings specified 10" (254mm) outside diameter but the closest pipe that I could buy was 273mm OD. Consequently the size of many components had to be modified.

I converted the drawings to metric and re-drew everything to verify that modified parts would fit together. Other model engineers stay with imperial dimensions. Your choice.

Paul.

Hi Jason (and all others), there have been a lot of good suggestions offered but I think that we have all gotten a little side tracked with clever designs instead of looking at the real problem.

The original question was how to make a "D" shaped hole. and later Thomas said :-

" Yes, this is to go on an existing electric motor with this shape already on the end of it's shaft - it is also too short to cut a keyway or any other hole in it as the motor would foul onto the chuck.

I could do a simple grub screw job but the mechanism it is powering will be under a lot of resistive torque (is that a term??). In other words the motor shaft needs to have a really good grip on the arbor that requires this odd hole, otherwise it may fail and I am unsure if a grub screw is up to the job. "

This sounds like a standard motor and pulley arrangement (Thomas please confirm) which normally uses a grub screw to lock the pulley to the shaft.

My lathe has a similar arrangement with a 1kw motor with a 16mm shaft and a flat on the shaft. An aluminium vee belt pulley is only secured by an M8 grub screw. The torque from small (1440 rpm) motors is not that great and a grub screw is all that is needed. The secondary shaft and pulleys run at a much slower speed and much higher torque, therefore it is fitted with a key plus a screw to clamp it in position.

Paul.

Hi Michael,

Making a square slot in the side of a hole is very easy with a keyway broach, simply by pressing it thru the hole. The difference with this application is that the shaft does not have a slot. And yes, the square corners are stress raisers but rectangular or square keys are used on millions of pulleys and is the normal way to attach it to a shaft.

You have stated that the pulley is subjected to high torque which suggests that it should have a proper keyway and key and should be firmly secured to the shaft by using clamping screws or press fitting the pulley to the shaft. The shaft should be removed from the motor if you intend to use a press fit otherwise you may damage the bearings.

Paul.

A similar idea to the half round hole and insert would be to broach (or cut a slot) a rectangular hole and use a rectangular key.

Paul.

Available on fleebay from $65 - $360. Depends on make and precision but includes a dial indicator.

I had previously bought a cheap set of telescopic gauges and that's what I got. Cheep!  Was not happy with them. Quality gauges are a different matter.

Edited By Paul Lousick on 01/03/2015 11:10:08

These are a bit more expensive but eliminates the need for the correct "feel" required to correctly measure a bore diameter. Easier for us less experienced operators.

Paul.

Edited By Paul Lousick on 01/03/2015 07:20:03