Yet Another Stuart Major Beam Engine

[simplyloco]

Thanks Willy, soon be finished, then it will blow your socks off! 

[simplyloco]

I've Just Discovered Rippers!

I thought that I knew enough about precision engineering to keep me going until the end... but today i found a little 10mm end mill in a drawer, bought as part of a job lot, and it had these odd serrations on the flutes. I had never seen one before in all my 59 years in the trade.  I slapped it it in the ER20 chuck and started to trim the end of the parallel motion links. Much to my surprise the thing cut steel noiselessly at 400 odd rpm, with no vibration at all, and left a pretty damn good finish, far better than the 4 flute one that I used to rough out the inners. I will use it again!
Never let it be said that an old dog can't learn new tricks...!



As an adjunct, I managed to get a nice taper pin fix on the crosshead: I wasn't interested in gib keys!

[crueby]

Huh. I've seen that style end mill but never tried one, assumed like you did that it would leave a rough finish. The serrations must be offset to match the gaps, neat.


Another old dog willing to learn a new trick!  Voof!

[Kim]

I have seen those called rough cut mills.  I've got a few and they do go through stock faster than your standard end mill.  But I've found that they don't leave as smooth of a finish as a nice sharp 4 flute climb cut does.

And unless I'm removing a lot of material, it just doesn't seem worth it to change end mills for it.  But they do remove material fast!

Kim

[john mills]

called differant names  RMR   rippa    but much the same used them starting in 1980s used 5/8"dia for pro filling or cutting out tools in first a beaver cnc mill then latter in much heaver  mazak miachining enters 1" and 1 1/4" dia full width and into 32mm thick tool steels they were extant for cutting out shapes cam plates all sorts of shapes for the roughing cuts and were finish did not matter where sizes were important
a finishing end mill used .it was much easier than spending hours leaning at the band saw i did often have to change to the 1" as when the 1 1/4"dia got a bit worn the feed axis would over load but using cutter compensation easy to change tool dia within limits the way the program
was written i had no cad cam in those days all just g and m etc codes profile worked out with a calculator .
JOHN  i don't think these cutters were in tended for finishing they leave a rough finish.

[simplyloco]

SNIP
JOHN  i don't think these cutters were intended for finishing they leave a rough finish.

Hi John
You know it, and I know it, but that doesn't alter the fact that this modest little cutter left an excellent finish!
I will pursue matters further...
John

[simplyloco]

I warmed up the workshop today and made a start on the drop links. A lot of beam engines don't get finished because these links and associated bits can be a bit tricky! I started with some 3/4" x 1/4" flat MS, and went from there.



Make yourself some filing buttons: 11/16"OD with a 7/16" boss. File and polish.



Tryout. Hurrah! It looks the part!



Now we are getting somewhere!

[Admiral_dk]

Hurrah! It looks the part!

Oh yes it do 

[simplyloco]

Nearly there! 

[simplyloco]

Drop Link Slots

It was a dull wet day so after shopping to fill up the deep freeze in anticipation of yet another lockdown I had a go at the slots for the gibs and cotters. I was going to cheat and make deep slots with an added filler piece, but as I had a new 5/64" slot drill I reverted to the traditional method! I have a very posh DRO but two bed stops are a far better proposition when making fine cuts with delicate slot drills. This is because I don't have to look at a remote display whilst moving the work back and forth: I can concentrate on feeling the work.
This is what you land up with if you are careful. I made a slight mistake on one slot which will be filled with soft solder later...



Every slot has to be in exactly the same position on all four links, so I made an end stop for my new vice. I removed the fixed jaw and tapped it M6. The rest should be obvious from the pictures!



The link is sitting on a parallel and is pressed up to the stop while tightening the vice. Soft hammers are not necessary!



I drilled all of them 1.8mm at each end of the slot to give the slot drill a start. Chain drilling was not necessary. You can see the bed stops in action. I then swopped the slot drill for the drill and took 0.7mm cuts until I reached the bottom, turned the link over and did the other side. Gib keys next!

[simplyloco]

This is as far as I got today before the dreaded hand cramps set in. They are getting more frequent these days, so I must drink more beer! I've polished one 75% to see how they look, and I'm quite pleased so far! Good job I found a needle hand file that was just the right size...



They all line up OK, so it's looking good!

[Admiral_dk]

Another tick on the list of parts to make and they look good 

So I agree that you have earned a 

Per

[simplyloco]

Another tick on the list of parts to make and they look good 

So I agree that you have earned a 

Per

I'm enjoying it right now!

[simplyloco]

Guess who has lost three of the rectangular bearing shells...?

Following the excitement of the F1 race I got a couple of hours in on the drop link bearings. I had made the basic shells, but they needed to be machined to slide inside the drop links. I've assembled two just to prove the method: take no notice of the gaps, there's a packing pillar to go in and the yet to be made gib keys put it all together - hopefully...


I can't find three of the bearing shells.  Never mind, I've got this far and it is looking the part and I am still motivated!

[scc]

Looking good             Terry