Member postings for I.M. OUTAHERE

I have seen thread plates that you can screw the offending fastener into to find the size but only in metric and sae - there may have been a whitworth one as well i can remember .

I know little machine shop in the USA do have one part #3459 but shipping will cost you .( usual disclaimer applies )

I use a similar method to Les which only works if you have a nut that fits the screw you want to check .

I use a peice of scrap as a holder so it leaves my hands free to operate a height gauge to measure the diffence in height the screw moves after 1 turn of the nut .

Bascally i measure the screw dia then find a drill a little larger than this but as close to the screw dia as i can get .

Then drill a hole in the scrap and set it up in the vice of my mill on some parrallels and get a height measurement with a height gauge , i screw 1 turn and re measure .

The difference is distance travelled per turn .

Divide 1inch by this and see what comes up if it looks odd then convert to metric to see if there is a match.

Sounds long winded but is useful for small screws and only takes a few moments to do but if you have some scrap flat bar large enough to sit the height gauge on then the set up for the milling vice is not needed as it can be clamped in the bench vice .

I have found the thread gauges that you get with a tap and die set are useless for anything with a fine thread and the fine metric units hard to see for small screws .

Ian

I would try the local harware or garden supply for some of those little rocks found in pebblecrete and give them a try on some scrap .

What ever you use needs to be dry otherwise it will form a clump of media in the tumbler / rumbler .

There as far as i can see there is a difference between a tumbler and a rumbler as the first rotates ( can also vibrate at the same time ) and the contents tumble , hit each other and what ever media you are using , a rumbler vibrates but does not rotate but the result is similar .

I use a tumbler to moly coat my bullets and a rumbler to clean cases .

I use corncob media for rifle cases and it is also used as labaritory bedding for lab animals , i then add some cutting compound used to restore car paint and rumble for 1 hour to dispese then allow 1 day to dry .

If it is not allowed to dry it sticks to the inside of the case and is a mongrel to get out !

This would also be good for brass , copper and aluminium .

Ian

Edited By SLOTDRILLER on 25/09/2012 05:21:10

Hi all .

Thanks for the replies .

Michael G .

I will have a look at or for some tufnol sheet and check the specs for suitability but this sounds good .

Martin : as from what i have seen with air tools and rotary vane vacuum pumps that i use at work the main difference is the positioning of the exhaust and inlet ports.

For an air tool it is usually at 12o'clock and 6 o'clock from the inlet to exhaust or there abouts and for a vac pump which will also blow pressure the inlet would be at 10 o'clock and the exhaust at 2 o'clock or there abouts .

I plan to plug the exhaust holes that are drilled in the housing and machine a new set at aprrox 3'oclock and re- machine all internal surfaces .

Michael W.

There is no chrome plating on this unit and it was also used to try and stop the chatter effect that vane pumps develop - this was from over reving the pump which caused the vanes to bounce or from sticky vanes - i wish the hardchrome company i worked at 25yrs ago was still going as i could have got mates rates on a chrome bore !

The pump will mount directly to a new 50cc two stroke engine i picked up on E-bay for $75au inc clutch unit .

The bearings will be sealed units and ther will be no oil feed as i don't want oil in my tyres !

The pump will be reving at around 6000rpm for i hope less than 2 -3 min per tyre then back to idle .

There is no metal to metal contact and the only wearing parts are the vanes in which i can make a few sets for spares .

I wish i could go back ten yrs in time as my workplace threw out boxes of spare vanes for vacuum pumps in a workshop clean up .

I always wonderd what they were made of though .

Ian

Hi all.

Whilst not purely a model engineering question it could have relevance for those who use die grinders or the like .

I am currently building a petrol powered air pump that uses the internals from a 3/4 drive impact wrench as a pump .

Unfortunately the unit i scabbed from the steel bin at work was in pieces and the vanes are missing .

I remember years ago pulling a broken die grinder apart to salvage parts and the vanes looked like some sort of material similar to phenolic circuit boards but maybe with a fibreglass matrix .

This unit will only be used to pump up tyres on a 4wd - so used in short burst and only needs to raise the pressure from 12psi to 32psi max .

Any thoughts on suitable materials would be appreciated and please understand this is only an experiment !

IAN

I wonder how long it will be before they work out how to make things using a powdered metal process?

Maybe a cold spray then bake operation ?

It may sound insane now but if you told the engineers at general motors in the 70s that the conrods of their engines would be made this way in the future you would have been my the guys in the white coats at the front door as you left !

I suppose only time will tell .

Hi Olaf .

You may be able to use a side and face mill like the one below mounted on a stub mill arbor .

You would essentially be using it like a very thick slitting saw so the rigidity of your machine may be an issue and so could the type of material you are cutting ( looks like alluminium ).

This one is 2-1/4" x 1" x 7/16" x 14t but are available in many different dimensions and tooth count.

Hi Joey.

I had a look at one of my i/c engine books (miniature internal combustion engines by Malcolm Stride).

And according to his reference you could use the following :

Cast : LM51

Machined from barstock: HE 15 OR HE 30.

For small compression engines (Diesel ) He recommends cast iron but no spec supplied .

I imagine these designations change from one country to the next etc so you may need to search for an equivalent on the internet .

There have been many articles in Model Engineer regarding engines so try there .

Alternatively try the MODEL ENGINE NEWS website as they have masses of info on many types of engines .

With a 40MM bore i would guess that you are using piston rings ?

Are you sure that it is not them that is seizing in the bore (ring gap too small )

And if you are using rings try a little more piston to cylinder clearance say 3-4 thou .

Are the pistons oval ? Should be smaller accross the wrist pin (gudgeon pin hole ) to allow for deflection or any flexing .

Ian

Is it possible to make the threaded 50mm section then machine a 6 - 8 mm hex (male) on one end ?

You could adapt a cheap socket to fit inside the threaded hole for the grubscrew and engage this hex to tighten the screw - i suppose it would depend on access and what clearances are present etc.

I take it that the original grubscrews are not available from the manufacturer ?

Ian

Oddly enough it appears that you can buy an M10 x.75 tap and die !

What one would use it for is beyond me !

M10x .75 is not listed as an ISO thread pitch that i can find so buying bolts will more than likely be impossible .

You may have to make them and cut the hex socket with a wobble broach .

IAN

Hi Garry.

I had a dig around on the net and you can get M10x 50 Socket head set screws but none state the thread pitch and it seems only in stainless .

Also try- socket head grub screw - as this also returned a few sites one is Brighton - best  international and they have an outlet at cradley heath - west midlands .

[email protected]

The thread pitch for M10 seems to be either 1.25 or 1.5 only .

M12 HAS 1.75 PITCH  .

What are they for ?

Ian.

Edited By SLOTDRILLER on 05/09/2012 06:22:05

I like your work Wolfie !

Now you need to accessorise -

The endmill and four facet drill sharpening jigs by HH are what i made next and they work well.

IAN

Hi Raymond .

I own a similar machine to the lux (dovetail column i hope ?) and also had some issues but had a play around and found that the column had gunk under it and was not truely at 90 deg to the table .

Now you say that it trams within a thou @ 225mm circumfrence and about the same if you wind the head up the column - what are you using to test against ? an angle block ? Make sure it is 100% parrallel to the axis you are using as a datum .

When you raise and lower the head the locks must be loosened so the HEAD would follow the inside of the dovetail and not the flat base it is meant to bear against when locked - could be mis -leading .

So try clamping the locks at each end of the travel so the head is bearing against the flat parts of the column and confirm the readings .

Have you tried to tram the quill with the locks on the column dove tail as loose as when you checked the vertical movement of the head for trueness ?

You could try to tram the quill to column and see if they are parrallel but this is a mission and would need some tools made . also the spindle needs to be locked so it cannot rotate but can move freely up and down .

I'm sure they use a taper gibb set up on the column and , maybe there is an issue there ?

Have you tried placing a block of wood under the quill then using the downfeed apply a small amount of pressure before locking the column locks ? - see if there is any change .

I would also ensure my table locks are tight before doing any vertical measurement - just to be sure - after all that what you are ultimately using as a datum .

IAN

Hi ALL .

Thanks Rod i will search for SH dealers and see what comes back , i think the only other place i managed to find it was through Hemminways but but the price tag left little to be desired !

Ian sc , i think that is where most of the material on the DVD is from as there is the odd mention of popular mechanics .

IAN

Hi all.

Thanks for the replies and links .

I ended up buying the LC MASON book as well as one by Gingery and err a few other as well - never let me loose in a book store !

That reminds me i must hunt around on ebay to se if anyone is selling building Mastiff by Mason also - i know i can buy it through a store but it is expensive !.

Regards ...

Ian

Very funny !

The skit about the engine starter was from a show called the comedy company that ran here in Australia .

How they didn't cop a law suit from WYNNES is beyond me !

They also did a skit featuring a suspension repair spray call the suspensions r**ted and one for the whole car is r**ted .

It was hillarious !

SHIFTER /ADJUSTABLE WRENCH : Used to machine the hexagonal flats from bolts and nuts , also doubles as a hammer .

STILLSONS /PIPE WRENCH Used to apply a knurl to the bolt heads that were macined by the shifter or anything else that is deemed too round to get a spanner on, also doubles as a hammer - should come with instructions as some can't seem to come to GRIPS with the fact they only grip in one direction .

IAN

Hi all , i just finished looking at a CD i picked up on E bay for a couple of bucks which has some weird , wonderfull but mostly bizarre plans from yester year and one was a small lathe made from angle ,a few blocks of steel and other bits 'n'pieces .

The dovetails were not machined but rather some pieces of square steel were filed to the required shape then screwed to the saddle and likewise for the cross slide to form the dovetails .

This has now got my curiosity running wild so i decided to do a search of the ME & MEW site looking for any articles about building a small lathe at home .

Result = 0

I am well aware of the stepper head project currently running in MEW but was looking for a small manual lathe instead 12" (300mm) or so long .

Could make an interesting project down the track- maybe a Nano lathe or something .

I can't remember seeing anything like this in the MEW back issues but it has been a while since i read them !

Ian

That is a very interesting site (long island indicator ) and it's good to see they are critical of the home grown brands as well.

I suppose that most of us would not even think about the quality of the internal mechanism and would shop for known brands thinking they are getting a top of the range unit .

IAN

Hi all thanks for the replies .

I will have a look a these and look at a reputable brand .

I dunno about forking out 100 quid + for a cutter tho - probably be to scared to take it out of the packet

I noticed in the picture John posted that one of these cutters has a serious helix angle !

IAN

Edited By SLOTDRILLER on 01/09/2012 01:42:41

For centering in a lathe i would steer away from a digital unit as a needle is easier to see.

A plunger type will give you more travel and will allow you to set things true or offset in a four jaw chuck .

You will most likely find that for the price of a name brand you could but a plunger and lever type of a cheaper brand .

I have both of these and both chineese made and they work fine but do have a feel of the mechanism particularily on the plunger type( slowly push the plunger in ) as some are a bit rough or the needle will jump ( it should be silky smooth)

There are also different dial sizes from around 1 inch upwards and the biggest i have seem was around 5 inches but i would stick with a dial size around 2 inch unit for a plunger and 1.5 inch for the lever.

Having a look at the arc eurotrade catalogue(usual disclaimer applies) i see they sell dial gauge contact point set that makes a plunger type gauge more versatile and with the bent stem fitting you could use the gauge to indicate the inside of a hole - something a lever type gauge is made for .

As for resolution .001" or .02 mm is all you will ever need as with a little experience you will be able to read down to a couple of tenths anyhow .

IAN

Hi all.

I'm sure this has been asked before but my searching via the generic search on this site has yielded little.

So what is the deal with solid carbide endmills ?

Pro's ,con's and thoughts .

Are they worth a look ?

They seem to be getting cheaper and fleabay has millions of listings .

IAN