Member postings for Chris Gunn

Speedy, look at Rotagrip's website where they detail all the dimensions needed to identify and also describe chuck jaws.

Chris Gunn

David, Having had a look at MichaelG's link, the Orkot is similar to the Ketron Peek HPV.

Chris Gunn

I used a material called Orkot for my die blocks on my 4" Garret, after having used it at work on something subjected to severe loads on a feed chain, where it stood up very well. These die blocks have been in since 1997, and there is no noticeable wear to date. The material has graphite in it I believe which helps with lubrication. I have used the same material for my 6" Garret 4CD die blocks. It is available, and a google search will give some suppliers. There are similar materials out there.

Chris Gunn

Why not make them in two parts, a steel core to take the load, and slip on a brass hexagonal sleeve for appearance, hold the sleeve on with a screw or pin on the underside or Loctite it.

Chris Gunn

Do not be too downhearted yet, someone may buy it as a going concern.

Chris Gunn

Adam I have a lathe with an old but good Burnerd chuck on it, but missing some jaws, jaws for this chuck are obsolete, so the chuck is not much use.

If you can get spares for the newer variation, I would buy that.

Chris Gunn

I would start with all the wheels if you have the castings, all can be machined together, all similar parts, then build the wheels, again common methods to front and rear, then make the front end, then rear axle parts. when you get the boiler make yourself a trolley with castors to support the engine, arrange it so the wheels will be a few inches off the ground, then you can move it around to work on, it will be at a better working height, and when you get to the motion etc, you can turn the engine over, rotate the wheels, check gearing and so on. when the time comes you can run the complete drive train to test. As Paul says shop around for laser cut parts, seems to be overcapacity where I live, and good prices seem possible.

Chris Gunn

4 of us went on Sunday, and had a good day, but we were disappointed we could not get our traditional bacon butty at the café on the way in, instead the only option was a very over priced supposedly German sausage. We did not think they were as good as the real thing. None of us bought a lot in the show, we felt the trade stands are reducing in number every year. We all miss the used tool stalls that used to be at the show, always a good place to get quality kit at good prices. The high cost of stand space was mentioned by some of the traders as a reason for this. However we thought it was nice to see the larger number of children there, attracted by Robot wars and the like. We all liked the Tamiya trucks and diggers display as something different.

CG

I can confirm the method that Nigel mentions above. We used to make thousands of rings from this material to use as cheap springs to hold nail gun jaws closed. We had a modified pair of snips with a vee guide attached to allow us to cut the material square, this is important if joining the material by hand, as a tapered cut can cause the materiel to slide sideways out of line when bringing the ends together. We had a modified pair of pliers with Vee jaws in which the material could be located in line and clamped. We had a soldering iron with a specially made flat tip coated with Teflon. This was held in the vice and warmed up, then the pliers would be brought to the vice to straddle the tip, and when the ends melted, the joint was slid off the tip, and the jaws squeezed together to make the joint. Like all things some practice made perfect. Our star ring maker would not bother with the pliers, as it was quicker to do it by hand, but he made thousands and had plenty of practice. One other thing to bear in mind is that if a mistake is made, one needs to cut out the bad joint and 5mm or so either side of the joint to get rid of the previously softened material before having another go. The Teflon tip was needed when making lots of joints, as the softened material can pick up on a plain steel tip, but should not be an issue when making one or two joints.

Chris Gunn

John, look on the bright side, that swarf will be worth about £140

CG

I think software is a tool, and I feel I do not know enough about it. From my perspective at my age and with a fully equipped workshop, I think I would be unlikely to change my equipment and learn CAM, there is a steep learning curve for me, as I never used this in my working life. I would prefer to be cutting metal than spending the time I know would be needed to move up the curve. That said, I am still interested in what can be done and how it is done in general terms. I do use CAD though, and used Dos based Generic Cad for quite a while, (anyone remember that?), and then Virtual Cad, and dabbled with AutoCAD. Now I am dabbling with TotalCad. A good general piece on the pros and cons of the various CAD offerings would be useful. I use Office and Excel, but what other software is worth considering?. I also read posts where various different operating systems are mentioned in passing like Linux and Ubuntu (?). I would welcome a piece giving the pros and cons and experiences of these systems as well. It is obvious the knowledge is there amongst our ranks, and some basic information and how this is applied would be of interest to me, as being retired now, I am not exposed to all this information as part of my working life. I know the information is out there to be found, but there is too much general stuff, and I would sooner learn from someone in our hobby who has similar interests and experience.

Chris Gunn

A couple of points relating to the above, there is a Rushton and Proctor roller with the motion removed and fitted with a Nuffield engine that belongs to Alan Eaton that is rallied local to me in Northants and round about. It is known as " Nuffrush". I started building locos way back, but switched to road steam about 15 years ago, I now have 2 road locos and have nearly completed another, and the freedom to take and run them anywhere is a real bonus to me.

Chris Gunn

I would keep it, it may come in handy one day.

CG

Muzzer thanks for that, I have advertised for a scrap spindle from a Bantam without success, so I could make something similar from it to transfer chucks from my Bantam to my rotary table and so on. It seems to me you have already done 3/4 of the work required to write it up, so I would encourage you to go a little further so we others can make one. Thanks again, Chris Gunn

Just be careful when drilling holes in gunmetal, the drill can easily snatch in the work, so make sure the work is securely clamped in the vice, and the vice is clamped as well. DO NOT be tempted to hold the workpiece by hand. Also do not be tempted to put a pilot drill through and then open up the hole, as the drill will snatch for sure.

Chris Gunn

Paul, good luck with your equipment, my comment concerns the choice of engine, I would recommend the 4" Garrett which was my introduction to traction engine building, for a number of reasons, first the drawings are among the best you will find, every part seperately detailed, second the supplier will supply raw castings or machined parts, with your choice of how far you want to go down this route, third the finished result is pretty robust, fourth the parts are bigger to handle making life easier if your eyes are getting worse, and last a 4" engine is much easier to run on all fronts than a 2" if you intend to rally it, and will handle a road run if you are that way inclined. Transporting the finished article will require a different approach than a 2", which may or may not be a problem for you, depending on your resources.

Chris Gunn

To get back to the original question, the easiest way to chip a carbide tip, is to switch off the machine spindle with the feed still engaged. This applies to the mill and lathe. Disengage the feed, then switch off the spindle. I was taught this during my apprentiship, and rarely chip one following this principle, unless all hell breaks loose, and one has to hit the emergency stop.

Chris Gunn

If you have a stop to trip out the feed, find something else to do while the swarf is being generated.

Chris

Coalburner, I have a complete unit for my Bridgeport, that looks just like the picture, Where are you in the country? You are welcome to come and measure it if you are close to Northants

Chris Gunn

How will the original patentee find out you have copied his idea?

Chris Gunn