Member postings for Gone Away

There are hand operated shaper castings available from Martin Model in the US (I'm in Canada so it's not quite the shipping problem it would be in the UK). I've considered something like this a few times but wonder how much physical effort is required. Does anyone have any direct experience in that regard?

Oh, absolutely .... and the more examples the better for people coming after.

On my mill, the only thing that limits the cross (Y-axis) travel is the table crashing into the column. Putting the scale on the back of the table would have reduced the cross-travel which was not an option for me. I'd never found the table stops on the front to be particularly useful so their loss was not an issue and mounting the X-axis scale was pretty simple and direct using the slot and existing holes. Bit of a no-brainer in this case.

(Although I later bought a power feed - you can see it in the pics - which uses the front slots for it's limit-stops. I'm running without the stops at the moment but the article in the latest MEW, while not directly applicable, has started me thinking .....)

The most difficult mounting for me was the Z-axis scale which necessitated a two part cantilevered bracket which, as you say is best avoided if practical for reasons of stiffness. It can be done successfully though, if you need to, by machining custom "structural" brackets designed for stiffness rather than simply using what comes to hand. The Z-axis mount took me probably 8 hours to machine (a fast machinist I ain't) but I think is worth it for the flexibility (in locating the scale not in the bracket ) it gives you.

Edited By Sid Herbage on 03/11/2012 14:33:08

er .... red face .... I got my X and Y confused in my message with the pics up there.

Mine has the angled sides to the base but could they just as easily have been vertical for all the difference it would have made (the moving head bracket could have been ever-so-slightly simpler).

I'm likely missing something on X3 from Jason's picture.

If I understand you guys correctly, the dimension you are talking about is from the top of the scale to the bottom of the read-head. In that case, on my Ditron scales, this is 50mm. (I didn't realise when I bought them that they had a 39 mm version for not much more money. That might have been easier to mount - but I managed).

This is how I mounted the X-axis to my WM14-WM16 (about half way between) lookalike. There's plenty of room in this case but I don't know how this machine compares with the X3:

Since the scale is mounted "upside-down" I installed an extra wiping seal at the top (regular house-door seal). See other pictures. No machine disassembly was involved (although I didn't have the power feed at that time).

The Y-Axis I simply mounted using the front table slot (that normally carries the travel-stops .... I discarded those). For the Z-axis I had to make up a special bracket (relatively complex to maintain stiffness)

Sorry, Clive. When you referred to "size", I assumed you were talking about the length and it seemed strange to select a length based on the room available for mounting.

All clear now.

> I have to dismount both X and Y slides to mount the X slide anyway.

Ouch!

I don't understand that statement Clive. It seems to suggest selecting the scales by the available space to mount them.

What you need to do is check/measure the end-to-end travel of the axis concerned and select a scale with a measurement length slightly larger. Any smaller and you are either restricting the travel of the axis or (more likely) you will wreck the scale by overtravelling it.

Once you've selected the scale you then have the (sometimes thorny) problem of fitting it into the space available.

I'm referring here mostly to a mill but the principle should apply to a lathe as well (although some - eg cross-slide - travel may be a bit "open ended" and you might then want to fit a positive stop. .....just thinking out loud haven't go around to doing the lathe yet).

In a way, you've hit the nail on the head. Once they have gone this route, people no longer consider it a luxury.

[ BTW - you seem to have, deliberately or accidentally, added a background colour to your text - in this case grey so it isn't showing against the normal background (but does in the emailed version), If you are experimenting in that direction, please, please reconsider. There's already one person around here doing it (with a sickly yellow that I presume he considers kewl) and I hope it doesn't catch on. Most people set up their browsers with text and background colours that they are comfortable with and don't need others forcing their own preferences.

Sorry - that turned out to be a bit of a rant. ]

Unless you are squirting so much cutting fluid that it and swarf are flying all over the shop, in your eyes, up you nose etc., I think you are worrying unduly with this. If you mount it in the "customary" position up at eye level I don't think you'll have any problem. At least I never have.

You might want to consider mounting it to one of the small, light-duty LCD tilt/swivel mounts that are available inexpensively these days. You can then position it for comfortable viewing wherever you are standing.

As for the scales, simple covers that shield the scale from the direction of flying swarf/fluid are normally sufficient. (This is easier to implement on a mill that the lathe I think). In fact, on my original mill setup, I simply taped a flap of plastic sheet to hang down over it and ran with that for a couple of years. It fell off once or twice and was taped back on but it did the job perfectly well.

I started with capacitive scales and they worked OK for me but sometimes with some dither in the last digit. They are also known to be somewhat noise prone and vary in which side of the supply is grounded - important if you are powering from an external source.

I later bought three 5 um Ditron optical glass scales direct from China (300mm, 200mm and 60mm) for $53 each and they have been wonderful and have first level sealing against swarf/fluid ingress. (There was a $75 shipping charge although they got to me in Canada in 2 days). Some people in the Shumatech Yahoo group are doing bulk purchases to split the shipping and also to get a slight discount on the scales. Ditron also sell readouts for a decent price.

Edited By Sid Herbage on 02/11/2012 15:12:20

Me to and it becomes automatic.

Problem is, if you follow this rule with a magazine, drawings in 'landscape' format will end up with the bottom or top to the fold depending on whether they are on the left or right page.

As a practical point, I would personally prefer that such drawings be printed with their tops to the fold (bottoms to the outside) in either case because, when reading at a desk or table, I prefer not to have a page width between me and the drawing.

No doubt he did know but unless it was precisely three years to the day (unlikely), it's quite legitimate to say "approximately three years" (or "some three years"  ). Better than something like "2 years, 11 months 1-1/2 days" which is stuffy and over-precise.

Likewise, your child. (Of course if your child is 8 years old today, happy birthday to him/her )

Edited By Sid Herbage on 18/10/2012 00:54:52

OED (and time-honoured use) doesn't actually agree with you. " ....some three years ago" is perfectly correct usage,"some" simply meaning "approximately" in that instance.

Granted, to say something like: "some three 1/2-inch bolts" is a bit silly since 1/2-inch bolts usually exist in whole numbers and with a small quantity such as 3 there shouldn't be any need to be inexact. But time intervals are certainly divisible and may need to be approximated even at quite a small number.

(Then again, OED is even starting to allow "myriad" as a noun to creep in so ....).

I doubt that MHS will have it but there's this: ME Vol

(eBay item no. 330799473409 if the link doesn't work).

Edited By Sid Herbage on 10/10/2012 23:17:54

Thanks Ian and Derek. I have one of those profile tools sitting around doing nothing much - I'll give this a try.

Derek, is the profile tool insert HSS or carbide? If it's carbide, do you have any problems with the interrupted cut?

Yes of course - but I was clearly responding to Dave M 's post.

That's possible with many 2D CAD systems which in many ways are really just manual extensions of the old drawing boards onto the screen. In that case if the user isn't "fluent" in projection systems misteaks can happen. (Although young or not, anyone producing drawings professionally should at least be able to get the projection right .... and where's the checker anyway? {rhetorical]).

Modern 3D CAD systems operate differently however and once the configuration is set to the projection system of interest (1st or 3rd), drawing view production and placement is handled by the program and will be correct.

With respect, Dave, the kind of gyrations you describe, (while fairly typical of toolrooms and machine shops) are more of a sign of people who are not completely comfortable with drawing projection systems than anything else. Experienced Engineers and Draftsmen do none of that. They simply look at the drawing and "see it".

An analogy is parallel parking a car between two oher vehicles at the kerbside. Novice drivers have have all sorts of rules .... line up this corner of the car with whatever .... now turn the wheel until something else lines up .... now turn the wheel back etc. The experienced driver just drives the car into the space, backwards.

Edited By Sid Herbage on 17/09/2012 02:03:16

Most (probably all) drawing standards require hidden lines (or further views) to be used if the design intent is unclear without. In this case, with no hidden lines, the legitimate assumption is that it's a solid, truncated cone (frustrum).

What do you make of this? on a drawing received (from the UK) a while ago.

I enjoyed the article on crewdrivers for instruments in MEW-194.

I have several instruments: multimeter, oscilloscope etc can they be used with these? To be honest, I didn't know they had crews but it sounds like a good idea to drive them - might make the b***ers work a bit better.