Making windscreen wipers

[Matty F]

Another little project to while away a day or so. Here's a rusty 100 year old windscreen wiper. I needed to make two new ones. I found a big bit of brass rod and some sheet steel and a bit of steel rod:

are the new bits. A modern wiper blade was available but not the other bits which I have had to make: used the milling machine to cut the flats and the slot. The whole thing will be painted black except for the wiper blade. Funnily enough the vehicle will probably never be driven in the rain, so the wiper is just for show. It's intended to be manually operated since there is no motor! There's really no suitable power supply.

Cutting off the brass bit on the lathe:

course I used a different tool for turning the brass. I must learn how to do diagonal cuts. That was just done freehand. I imagine there's a fancy way to do diagonal cuts but I hate it when everything goes wrong and the tool winds into the chuck! Not that I've ever done that but I hate the idea!

[John Rumm]

Kind of like doing a diagonal line on an etch'a'sketch.

I am no expert on these things, but would have though for small bits like that, making a tool with the required angle ground onto the cutting end would do quite nicely - just plunge into the work until you have cut to the required depth, then back off move along and repeat.

For longer chamfers you may be able to rotate the cross slide on the tool holder to the required angle.

Saw someone do that in our college machine shop - putting the finishing touches to a bit of work he had been working on for a couple of weeks. Wanted one final skim pass on a spigot that protruded from a centre block. Got it all lined up in a 4 jaw chuck, and then grabbed the screw cutting lever rather than the standard power feed! The tool post etc quickly wound right through his work and hit the chuck, and the whole lathe was jumping about the floor. Fortunately there was someone close enough to jump on the emergency break for him.

[John]

Best to keep the leadscrew in neutral.

[Steve Walker]

All the lathes that I've used have had a carriage, with a cross-slide mounted on it at 90° (both of which can be power fed - one at a time) and a manually operated top-slide on top of that that can be rotated to any angle, allowing angle cuts.

SteveW

[Matty F]

I was only making the one part. Making a special cutter and trying to fix it in the lathe was just too much trouble. Besides somebody is going to slop black paint all over this anyway!

Yes I keep forgetting about that. So much to learn, so little time.

[John Rumm]

Indeed - freehand is fine for such things. Did something similar myself when I wanted a couple of adaptors to allow 1/4" UNC threaded accessories to fit the M4 threads on my cheap cable rod set:

?title=Image:RodTorchAdaptor.jpg

[Matty F]

?title=Image:RodTorchAdaptor.jpgI see the tell-tale signs of freehand, like mine! Next time I'll have a look in the drawer next to the lathe. There are dozens of bits that someone has made for spcial purposes. Most of them are too small and look the same. When I did make a bit for this screw head, it did make a superb job. And all the screws then look the same: having made a bit it's quicker to use it, and no chance of winding the tool the wrong way twice like I did with the wiper brass job. That makes a nasty noise and people look in my direction!