Milling Machines

[Kane]

Hello guys
Been a while since i last posted on these boards.

Im currently attempting to build a 5" gauge simplex
Frames, stretchers and some bits of the water pump in place, these have been sat in the workshop for the past 2 years or so with not alot going on.
So i have now decided to start machining the first hornblock casting, using my ML7 and milling attachment.

Its coming along albeit slowly. Hit a few snags along the way, but i expected it as ive not really done much milling before. (not really done much lathe work come to think of it )

Anyway back to the topic.
I've been looking at milling machines on ebay the past couple of days, most of them seem to be horizontal millers.
My question (or two) is that can these horizontal milling machines do everything a vertical one can?
If so which would you guys suggest to buy, vert or horiz?

Thanks Alot
Kane

[the_viffer]

In my experience verticals are more versatile than horizontals.

For slabbing the horizontal wins every time. It is mighty hard to hold an end mill in a horizontal tho'

Query how much slabbing will you do?

Why not buy a shaper?

[Tel]

the_viffer said:

In my experience verticals are more versatile than
Why not buy a shaper?

Now yer talkin' Fingers - wouldn't be without mine

[jackrae]

Slightly off the topic but I machined all my simplex horns on the Myford 7B

In fact since I bought my excellent horizontal Harrison Mill and made a vertical head for it I haven't done one bit of the Simplex on it

And I will own up to having sold for a song my 10" shaper - sorry chaps

Jack

[the_viffer]

I filed the horns up on my 5" 0-6-0 + 0-6-0.

I reckoned it was a good way to get the authentic clonking sound.

I have to tell you quartering was even more cowboy. It has got outside frames so I put the cranks and coupling rod on one side and snugged it all down with socket cap head cap head grubs and loctite. The other side I put the cranks on loosely, mounted the coupling rod and rolled up and down until it was all free and then nipped up the socket head caps.

It worked a treat. Also they now generate electricity from the tomb of KN Harris who started revolving at high speed.

Use it only at your own risk but a professional model maker suggested the idea to me.

Yeeeeee Haaaaaahhh

[Kane]

ok well i can probably cope with milling on the lathe for now

but here comes another almighty stupid question

i have the hornblock castings but how do you get all sides square (perpendicular)
i know its gotto be simple i just cant figure it out.

I machine two opposite sides of the casting so these are now parrallel, and then turn the casting 90deg and machine these two opposite ends, but then these two are not perpendicular to the other two parallel sides.

i thought about leaving the casting in place and turning the vertical slide, but there is no way of knowing when the slide has been turned exactly 90deg.

what is the "proper" way to do this?

Kane

[the_viffer]

Sounds a perfectly sensible question to me but are we talking horns on the frames here or are we talking axle boxes that slide in the horns (or rattle in my case)?

I'm just having a bit of difficulty visualising what you are saying.

And you've a vertical slide but no mill or shaper?

[Kane]

the_viffer said:

Sounds a perfectly sensible question to me but are we talking horns on the frames here or are we talking axle boxes that slide in the horns (or rattle in my case)?

I'm just having a bit of difficulty visualising what you are saying.

And you've a vertical slide but no mill or shaper?

im talking about the cast hornblocks that fasten to the frames.

And yes i have a vertical slide on the lathe but no mill or shaper.

Thanks for being so patient ;D

[Tel]

You might be better doing them in the 4 jaw chuck.

On my Simplex I just used pieces of 3/4" x 3/8" (I think) bright mild steel & slabbed the axleboxes outta an old cast iron sash weight.

[steammadman]

Good on yah Tell, ; once again a man after my own heart,why spend
your hard earned cash keeping someone in the money, make EVERY THING and keep yourself in the money ,and her indoors happy.
Cheers
steammadman

[the_viffer]

Err me? Patient? No I think there is some mistake. I think you are confusing me with someone.


Happy enough to talk all night about sensible machining questions like this tho'

If you've castings that do both sides then machine the back that rivets to the frame as snug as you can. Tidy up the axlebox bearing surface but don't finish to size. Make the upstand no more than the frame thickness. Rivet to the frames. Repeat for all horns
Rivet the frames back to back.
Mount the frames on the vertical slide about perpendicular to the spindle.
Stick the face plate on. If you are being really anal take a skim over the face plate. Clamp a bit of stiff square or hex to the face plate. Measure eg with calipers the distance between the square and the frames. Turn the face plate 180. Compare the distance between square and frames again. Adjust the vertical slide. Repeat until equal. The frames are then 90 to spindle and use your preferred method to machine the bearing face. Try to get axlebox size the same for each pair.

Fail
Drink yeasty beverage
Feel better
Repeat last two steps

Get warm glow.

Drink yeasty beverage.

Repeat last two steps.

[Kane]

thanks alot

that sounds like a plan to me ;D

will give it a try when i have some time

once again thanks to everyone

Kane

[Kane]

while we're at it ... instead of making a new thread

taps and dies ...

i have a drill chart that shows the size of holes needed for tapping and clearance.

but how do you know what diameter the piece of metal should be if you want to make a thread to screw into the hole you have just tapped?

eg for a 5BA tap you would use a 2.65mm hole? and then for a 5BA die what should the diameter be of the piece of metal to go into this?

is it the size of the clearance hole? (3.30mm in this case?)

Kane

[jackrae]

The BA thread system has a fairly basic formulae which all starts with size OBA

OBA by definition has an o/d of 6mm with a pitch of 1mm

From there on, each increase of BA number reduces both o/d and thread pitch by exactly 10%

Therefore 1BA has an o/d of 5.4mm with a thread pitch of 0.9mm

2BA has an o/d of 4.86mm with a thread pitch of 0.81mm

Another simple (unofficial ?) rule is that OBA tapping is the same as 2BA o/d and 2BA tapping is same as 4BA o/d etc etc

Same rule applies to 1BA , 3BA etc

trust this helps

Jack

[the_viffer]

I've much to say about tapping size holes. I don't believe the tables much. They might be fine for industrial use but hand tapping in drawn PB I think not. There is no room for it here and anyway I've not completely written it up yet.

In essence I think you can often safely use a little bigger hole than is usually quoted without damaging the security of the fitting, or risking your nerves, breaking a tap or the chance of spoiling your job by having a bit of hss broken off in it.

Jack has give you some rules for BA. I haven't checked them but there is a mathematical formula.

The general rule for male threads is the size quoted is the size stock you need. So for a 6mm male thread you need a 6mm rod. It took me a while to figure that out when I started off.

[Tel]

steammadman said:

Good on yah Tell, ; once again a man after my own heart,why spend
your hard earned cash keeping someone in the money, make EVERY THING and keep yourself in the money ,and her indoors happy.
Cheers
steammadman

That's always been my philosophy (geez - I didn't know I could spell philosophy) Madman. Dunno about keeping myself in the money tho' - generally driven by chronic poverty

[jackrae]

Update on the BA thread data

I got the pitch equation and the tapping rule correct but fell foul on the o/d data. Actual diameter figure seems to be a reduction of "around" 12% per step change

The following web-site contains all the data you should need

www.bhi.co.uk/hints/bathrd.htm

regards

Jack

[Tel]

Or our very own Alan Stepney has some good info on his comprehensive pages

www.alanstepney.info/page77.html

[steammadman]

Hi all ,
;D Tell keeps giving us that old speil about his poverty,
i always thought all ausies were sitting in the rose garden ,its just us hard done to english who know the
meaning of poverty , at least thats what i was lead to
believe when i was serving her majesty down under ,
in 1955.
Anyway Tell,my old mate,like you i dont beleive in spending my hard earned cash,unless i'm forced,(what
yorkshire man does ?, !!!).
Hear is a list of "stuff" i used on my "Bantam Cock", loco
Cylinders; ex tractor ballast weights, sometimes they
are of good cast iron, (my farmer cousin still does'nt
where the two he lost went, cheers Phil !!. )
Steam chests from the same scource
Steam chest covers ; from a broken manhole lid.
Cylinder end covers; from large sash weights, (salvaged (?) from a stateley home i was working on).
Pistons ; from the same sash weights.
Piston rings; from a lump of phospher bronze that fell off
the back of a lorry. (well thats my story anyhow.)
So as you see guys theres NO need to spend £50 - £100 on expensive castings, (These have seen one
boiler off,and still going strong).

[Tel]

Beautiful M-man, and you get all the more joy outta it for knowing how it was done. That's how i like to do things even when I got money - right now most of my money is goin' straight down the throats of the cattle. Still, hopefully I'll get it back one day.