Member postings for not done it yet

Plumber liquid drain unblocker is mostly strong sulphuric acid. Nasty stuff, not to be spilled, or got on flesh

As is often the case, some (possibly most) people don't know the difference between strong and concentrated with reference to these chemicals (acids or bases). Strong means well dissociated into ions when in solution (usually aqueous). Weak means the opposite (pH is a measure of acidity or alkalinity), while concentrated (or dilute) refers to the percentage of the compound (usually mixed with water, if less than 100%) in the substance/mixture.

Sulphuric acid as used for drain cleaning is concentrated. Pure acids are not necessarily ' strong' acids until water is present. Concentrated sulphuric acid has a very strong affinity for water, so removes water from anything it contacts - your skin suffers from both aggressive water removal and then strong acid reaction. Concentrated sulphuric acid will reduce sawdust to a morass of black carbon, whereas nitric acid will set sawdust on fire (as it is an oxidising agent as well as an acid.

Know your chemistry.

Oh, and btw, copper sulphate can kill you but it also can affect the nervous system in far smaller quantities.  A bit like lead poisoning, except that high blood concentrations of lead are more easily dealt with, by medics, than copper poisoning.

Edited By not done it yet on 16/07/2017 12:22:43

Like another current thread, copper sulphate is reeelly dangerous. It is a poison. Probably not allowed to grow copper sulphate crystals in school science classes these days, even though we used to do it without any problem 50 years ago.

Amazing that hydroflouric is on open sale. Just too dangerous. Nitric, sulphuric and other strong acids(or strong alkalis, for that matter) are bad enough in the hands of idiots or criminals, but HF is in a different league. At least the sales will be recorded (hopefully).

There are too many legitimate uses of chemicals to actually ban most, but hese criminals can source at least battery acid quite easily - and far cheaper than HF. Traceable records of sales will be the best they can do, I think.

Not all guns are banned. One can own, and use them, without being a danger to the public, but most criminals use guns supplied by a black market - often stolen or illegally imported. That does not impact our hobby, - but I dare to say it would be far from impossible for someone to make one on our machines. After all, they can bemade on 3D printers these days.

Where do you stop? Better to target the criminals with huge consequences, but that would still not eradicate the problem completely.

If theft is the motive, why use anything so dangerous? The recent case of the young lady and her cousin being doused with sulphuric acid would appear to have different motive. The person responsible should be locked away for a very loong time.

Yes, I will retract some of my previous post. I'm only a learner with the mill. Certainly not an engineer like some on the forum.

Not knocking you at all. Discussion helps us all. And if it gets a response from JB, that is good.

(para)Certainly better than milling on a lathe. What I was thinking is that you got it for a song, so a vertical head would be a great addition. Certainly worth saving up for. All the good bits are expensive, these days. Cheap chinese is cheap for a reason.

(para) I would be hunting around for a vertical head - they can be expensive, but don't eat anything and, as far as I can see, will hold their value - as they ain't making them any longer.

(para) I reckon a good Centec is likely better value than a modeller's

chinese vertical mill, and with the extra opportunity to mill horizontally. My Raglan is used for smaller items and when the other mill is set up for something else (but the power feed on the Centec makes a big difference, too). Looking at reports, many Centecs are only used vertically - a wasted opportunity, as the horizontal arbor is so much more rigid, being supported at both ends.

You can bet that Rod gets flatter finishes than one would easily with a flycutter, which needs perfect tram, or several passes with a small milling cutter.

You are going to need some long end mills if you want to use them in the horizontal 2MT taper? I can't see much advantage of using it as a vertical mill on its side. Undoubtedly there are some jobs, but few that would not be easier on a vertical miller.

There is only about 4" of cross travel available? You won't find many u-toob videos using a horizontal milling machine in this fashion.

If it were that good, they would not have bothered to supply the vertical head!

I believe they would take up less room than a collet holder or am I wrong in this .

You are right. Sure they do, but they have downsides, too.

Only taking a specific size milling cutter shank is the obvious one (no different than Clarkson holders, mind).

ER collets are far more universal (now) than either of the above, so making a riser block for your mill would likely be a better way to go. Then you will have more head space for your Clarkson cutter holder ... and also o

ffers more, with either ER or 2MT collets.

RS. Or whatever name they use these days?

Interesting that the lubrication holes for the bushes had not been drilled though!

Maybe the bearings are oilite type?

Where can you go out and buy conc hydroflouric acid? It is not an "open sale" item.

Any strong acid or alkali is dangerous - especially in the wrong hands.

It is not only engineers that might use the stuff.

Bio diesel, beekeeping, soap making are the first three that might affect me.

If you mean ER 32, I think you have basically wasted your money on one set or the other! Each collet will contract a usable 1mm or 0.040".

The imperial collets will compress by 1mm and the metric ones by 0.040" if required!

Sean,

I was going to reply much earlier on this thread, but things got in the way and parts became irrelevant.

The 1" arbor that came with my machine has no keyway and I am not going to put one in that - or the 22mm arbor I made recently. Yours is only a one horse machine, if that. So I am in agreement with Rod. para  

With cutters like slitting saws it can be better if the cutter can slip, should it jam, rather than the alternatives. Adding a full length keyway could cause the arbor to go out of true, so I would only consider a short keyway, if thought necessary. para  

There is no real need for a shorter arbor, for a machine such as this, I would say. If you wanted to make something, you would perhaps be better making an alternative support bracket/bearing that could run on an inboard bearing? Or an arbor of different diameter? para  

Making its own riser block to improve head space for a vertical head (when you find one) would be a useful addition.

Get a slab cutter, wide enough for your QCTP holders and any others that would help with that project. para  Job lots of second hand cutters occasionally appear on epay, some of which might still be in fair condition and the right size for your arbor.

Edited By not done it yet on 13/07/2017 23:28:47

Nige,

That is likely far better than most 3 jaw self centering chucks will achieve.

If you plan your work such that the item does not require rechucking, the initial chucking may not need to be centred perfectly - as long as the stock is sufficiently oversized - just the first cuts may be intermittent.

Turning between centres is the way to go if parts need to be removed from the lathe and replaced several times without fear of concentricity problems.

Trial and error is always the way it is done. Think here, if you trial it (measure) and reduce the error (run out) by one half each time, you should only need a maximum of eight repeats to reduce the error to close (enough) to zero (a bit like folding a sheet of paper in half and half again, etc). It is only that some can get there more quickly than others!

Check out the recent competition between Keith Fenner v Abom79 at the Bar Z bash 2017.**LINK**

Even they can be set a rediculous task to test their doubtless high skills.

Oops! Sorry, I wasn't thinking properly last night. Both my MT4 taper fittings are reducing sleeves, so no thread needed and no thread present.

Edited to add that it might be imperial if the tooling is old (5/8 Whitworth thread?).

Edited By not done it yet on 13/07/2017 16:05:18

I take it that this mill is not one of the newer flock of machines which offer different spindle formats?

I'm sure someone will confirm the pitch. But you could buy a bolt? Or take your MT4 along to somewhere that sells studding or bolts and check it out? Agri dealers, ironmonger/hardware stores, building suppliers all come to mind as possibles. I'll see if I can hunt out a bolt tomorrow, and try it, if nobody else responds.

What pages are you reffering to ?

lathesdotco

There are pictuees of the appropriate collets on both pages 1and 2.

It appears that the cutter picture you have supplied fits directly to the mill, with a drawbar? As the lathes dot co report states it looks like the Mkll mill used split collets with drawbar, but the same taper as on your cutter?

So is your machine a Mkl or Mkll?

Is that 20-30 thou with the quill in that fully(?) extended position? If so, what is it with the quill retracted? Solution might just be raising the table?

Change reference for test. They are not cheap.

Here is yet another vid. Yes, they needed to refill with leccy more often than they would with a dino burner over the 1500 miles, but not so much of a hassle. Plenty of fast chargers shown. Leave anyone interested to find the 'part2' video (or their numerous other videos). Even electric motorcycle tests.

**LINK**