Double Tangye in slow (very slow) progress.

Today, I made a start on the first of the two standards for my Double Tangye build. I have bored one leaving this one to do.

I made a boring bar to do the job out of a long 3/4" diameter bolt. The HSS bit sits in the end at a 45 degree angle and the bit can be advanced under control using a 4ba socket grub screw.........

..........and now for the boring bit !!

**LINK**

Having partially machined the pair of standards it was time today to do the job I have been putting of for weeks and that was to machine the cylinder mounting flanges but more particularly, the rear of the flanges indicated at "A" this being necessary because the cylinder retaining nuts need to sit square on the back of the flange and also the rough casting would not allow space for the 6BA nuts.

So having previously bored the standards to take the crossheads I used the same mandrel to mount the first standard to the chucked rotary table on the milling machine. I used a small end mill to reduce the casting diameter to allow space for the nuts and used the same end mill to face the rear of the flange.

This still left the area on the underside of the flange un-machined due to the corners of the casting foot "B" fouling the collet holder. I had no choice other than to "peck" it out with the end mill and finish with a small square file.

My die grinder smoothed out the step left by the end mill. I admit it does not look to pretty at the mo but when the painting has been done I am sure it will look OK.

I know that Jo on another forum used the same method to do the rear of her flanges and she was not relishing the prospect. If she's reading this I know the feeling Jo - a pig of a job.

Rik

Good to see you making a bit more progress on this one Rik

J

Hi Rik,

I built the Double Tangye a good number of years ago and I am sure I still have photos of some of the set-ups I used to carry out the various necessary machining operations involved. If you have any queries about that, let me know and I can scan the photos and email them on to you.

Alastair Sinclair

Because of recent workshop relocation and other stuff I have not been able to make any progress on my Double Tangye build. I have, more or less, got myself organised enough to make a start so into the shop this morn and machined the 45⁰ angled crankshaft bearing cap mounts on the two standards with a fly cutter.

Just a matter of removing a little at a time until the scribed line comes central over the length of the pad.

I must admit that working out how to do this took much longer than the machining itself. If you look at the first pic you can maybe see that the finish machined cylinder mount faces are up against an angle plate "register" clocked square to the mill bed. This ensures that the dimensions from said faces to the centre lines on the angled pads are equal.

Next job (easy) is to drill and ream a couple of holes through the base of both standards and into the base casting to take a couple of dowels. I need to remove the standards for further work and this ensures they will go back in the right place.

Rik

Edited By Rik Shaw on 27/02/2015 15:12:25

Please forgive me one and all, BUT what on earth is a Double Tangye?????????

Two singles on the same bed plate

Double high pressure horizontal steam engine base on one built by Tangye of Birmingham

Edited By JasonB on 27/02/2015 16:10:27

Thanks Jason - I can understand his confusion - it sounds like a dance to me! I can't tell a Wallis from a Tangye neither.

Rik

...it was rather boring! \Did it actually take any metal off, looks like no swarf in video (I know its not a real video, they went out in the 70s !!)

Fizz - course its boring. Its a challenge to make an interesting film of someone making a small hole bigger and I obviously failed to rise to the the nature of the subject. Sincere apologies for wasting your time.

Rik

.

No ... that was the Video Cassette Recorder

Video, and video recording, are alive and well.

MichaelG. [in Pedants' Corner]