Saturday, 6 August 2022

Cold Blueing

I had not heard of this until recently. It's a method to surface treat steel. It add a little bit of rust protection and colours the surface a dark blue.

I watched a few YouTube videos and picked one of the products that looked easy enough to use.

The process with most are similar:

  • Wear safety goggle and latex or nitrile gloves
  • Completely degrease
  • Lightly sand
  • Either paint on neat or soak in a diluted solution
  • Wash off and repeat a few times until the colour is as dark as required
  • Soak in oil for a few hours to give the finish a sheen

I cleaned the bits in brake cleaner and soaked in motor oil.

It won't stop rust if left outside, but it's a help in a workshop environment.

Mostly the result looks nice.


Friday, 5 August 2022

A quick change tool post for a WM 180 lathe

I'd decided after watching only a few videos I wanted a quick change tool post for the lathe. The main reason is that fiddling with spacers to align tools is a nuisance.

The Warco WM 180 has two things that make it a little awkward finding a tool post to fit. Firstly, it has an 18mm diameter boss round the bottom of the stud that the tool post attaches to. Secondly that stud is a fixed length. There is no way round the first issue. The solution is to bore out a recess for that boss to fit into. The second limits the choice of tool post.

I found several tool posts that had a bore suitable for the M10x1.5mm stud.

Warco do one, which you can pay them to bore out the recess so it fits the WM 180. It was not a design I had seen elsewhere and it was out of stock, so that ruled that out.

250-000 tool post

The style I see the most often, in YouTube videos, is with the expanding wedge dovetail. I like the look of it and the small size 250-000 is readily available on eBay, and at other suppliers, at a reasonable price. The trouble is it requires a mounting stud taller than the one on the WM 180. It's likely the stud can be replaced, but I didn't want to try to do that, if I didn't have to.

There's one I found, called a C3, but I just didn't like the look of the design of that.

T37 tool post

The one I opted for is a T37 which I purchased from eBay. I've seen similar designs with slightly different names and different sizes. The T37 being the right dimensions to fit the WM 180 lathe.

Now for the tricky bit. I had to bore the hole to fit the boss. I wasn't sure if the WM 180 would be up to that job.

It took a few aborted attempts but with a bit of abuse of the tooling I got the job done.

I centred the tool post in the 4 jaw chuck.

Part of the problem was that my boring bars were too big to fit in the 11mm hole and my Cobalt drills would not even make an impact on the hardened tool post. I'm sure it's not good but I found by starting the tip of the boring bar from the outside and forcing the tool against the surface and working towards the middle, I was able to take off a little bit at a time.

By forcing the tool against the work piece, I ended up with a slight slope towards the middle, which I had to sort out when I'd got to near the depth. It will not win any awards for quality but it fits and it works.

The new tool holder is a little lower than the original so I needed a spacer so the clamp would lock. I could have piled up washer... but I have a lathe, so I could make exactly what I needed.

With the spacer done, I decided I needed a taller handle so that the lever did not foul on the locking bolts. Another job for the lathe.

I learnt several new techniques including threading a hole and cutting a taper.

Between jobs I 3D printed a longer lever and a mini tool holder for all the allen keys.

A tricky bit was drilling the lever mounting hole on the 30deg angled taper.

I removed half a millimetre off the spacer, so that the lever stopped in the position I preferred.  The job took most of a day to complete and the result is working nicely.


Sunday, 24 July 2022

My First Metal Lathe

This weekend I got some time to use the lathe that I got for my birthday.

It's been about 40 years since I last used a metal turning lathe, so I've had a bit to learn. I found an excellent series of videos on YouTube that got me underway very quickly.

These tutorials by Blondihacks are concise, easy to understand and exactly what I needed to know.

Unboxing. There are lots of similar lathes all made in China.
Having read lots of reviews, I concluded that the lathes are pretty good but the state of what arrives can be a bit hit and miss. To avoid having a kit of parts, instead of a lathe, I decided to buy from a UK company that brands their own Chinese manufactured lathes, and most importantly checks them before  they ship and provides support.

I bought a Warco WM 180 lathe. It arrived in very good order, pretty much ready to use.

I built the bench that it sits on, over 10 years ago. The bench was intended for a lathe, but it's taken me this long to decide to buy one.

It comes with a basic tool post. To align the tools, it is necessary to pack them to the right height.

To pack under the lathe tools, I used short lengths of the metal strapping from the crate that the lathe arrived in. I found that tip while looking for what lathe to buy. 4 layers of metal strap, raised the tools to exactly the right height.
I bent the strap, so that it also brought the tool out to better line up with the set screws, that hold the tools in place.

To practice, I made a pair of presses to put the cups in to bike head tubes.

I've learnt a lot as I've gone along and I am pleased with the results of my first project using the metal turning lathe.