Thread: Assorted Basic Metal Working Problems

One commmon way of getting a true surface when filing on the vice is to mount a roller infront of the vice.

Easy to make, just a couple of arms coming up from the vice sides and a roller, adjustable for height between them. Obviously the roller must be of a softer material than your files.

Originally Posted by thumbsucker

[*]What is a good brand of hand files, even Nicholson is now made in Mexico, how have peoples found these files?

Bahco are pretty good if you can get them but I reckon the best are Vallorbe - made in Suiss. I use Vallorbe files to sharpen my chainsaw chains and they are very good. Try a chain saw shop. Usually they only stock flats but some carry the trapezoidal files used to sharpen square ground chisel cutters - ask for files to sharpend square ground chain.

[*]Because the triangular files are serrated on edges, I find its near impossible to make a clean 15º without rounding the corners of my dovetails. I have read the suggestion on grinding away the corners on the files? How would I grind such hard steel - grinder? or can I get files with only on face that is the cutting face. Just like floats for making wooden hand planes.

I have never seen triangular files without corner teeth but that does not mean they do not exist. You can use a grinder to take the edges off your self no problems.

Were can I get hardened steel angle in 200 mm sections? Without going out and buying angle, milling it and heat treating the angle?

If you find out can you let me know?

[*]How do you get a square edge in metal?

Pratice

[*]Anyone have any tips for techniques using hand files, like getting flat and square surfaces. I discovered that you can use the edge of the files like a hacksaw cutting into the brass

No matter what you do you do - if you try to file an edge freehand you always end up with some rollover. I like bodgy's idea or using the same Idea as the vice jaw I have used the same sandwich method to get a square edge. Start by getting a flat piece of wood and drill/cut a hole/slot in the middle of the wood. Place two pieces of hardened tool steel across the hole and sandwich the metal in between the two hardened steel pieces and let the metal sit a touch into the slot hole, you can then file the metal down to the hardened steel edges. I usually sand down to the hardened steel because filing eventually wrecks the file.

The other approach would be to adapt a chainsaw sharpening rig - see this thread

Peter McBride, who is a jeweller by trade but who makes dovetailed planes for fun, says this about files on his website (I have coloured the relevant passage red):

Files.
Two types of file are used, larger bench files and smaller needle files. Both are cross cut to avoid the risk of the file grabbing the work and spinning it in the fingers. This can cause a very deep painful cut to the tips of the fingers. The files are in a variety of shapes to suite the work, eg. Flat half round, three square (triangular) knife-edge. Often one face of a file is ground smooth to create a “safety edge” to allow filling critical shapes and dimensions without unwanted cutting in another direction.

So I would just set to with your 3 square file on the bench grinder and create a safety edge by ginding off the teeth on one side.

BTW jewellers' suppliers like AJS sell really good Swiss files, but they aren't cheap.

As for technique, I find that making sure that you hold the tip of the file in your left fingers as well as holding the handle in your right hand helps get a straighter cut. Also, leaving a little metal and draw filing that off (not possible with dovetails) helps not only getting a smooth finish but also tends to cut off any rounding over.

Jmk89 thanks for the link.

I will call Warren about the steel angle, for the purpose of getting a strait edge.

I will file down my corners to get rid of the round corners.

I will look into the round files.

Another question - I have some 4 and 6 mm brass that I need to solder back together. It is feasible to solder brass that thick and how many size soldering iron would I need?

Hi TS,
Are you building a Norris style plane per chance?!
I think Nicholson's are still OK, but have bought some lovely Bahco brand files recently. Sweet!
There are files with safe edges, mostly flat ones, with one edge sans teeth, and used to file against an inside corner without compromising one surface. No doubt other files can be doctored to suit, and a normal bench grinder will have no probs taking off the teeth. Note the sparks will look different to mild steel, one way of identifying the different steels.
I have spent many hours flattening and squaring steel, aluminium and brass with files, its just a patience thing. Use bearing blue, or even a thick Artline pen to cover the surface and scrape the high points with a straight edge/square, to determine which area to file next. Eyeball the edges you're trying to square with a quality engineers square by looking into the light, or out a window, which will amplify the gap by letting in light.
Keep your files clean with a file card (they will cut better, and not score the surface), and if pinning (build up of waste in the teeth) is a problem, apply a bit of engineers chalk to the file.

Good luck

Originally Posted by thumbsucker

Another question - I have some 4 and 6 mm brass that I need to solder back together. It is feasible to solder brass that thick and how many size soldering iron would I need?

Yes you can solder it but if you want any strength at all I wouldn't do with a soldering iron or lead based solder. I use silver solder and a MAPP torch or similar to join bits of brass. The join can be very strong but you will need a very neat fit for it to be at its max strength. I often add a 1/8" or 3/16" screw or pin to assist with alignment. The smaller of the japanese saw handle fittings towards the end of this post show some recent brass bits that were joined by silver soldering.

you'll need to silver solder if you're looking for strength, if need be I can do it for you as I have all the gear to do so.

Wilshire if you can get them they were good australian files, for the bottom of the dovetail try a small 1/2 round file , also remember files come in usually 3 grades smooth, 2nd cut and bastard, and there are also mill files which are without cerations on one edge( for filing up to a face without damaging it ) and have parallel faces ( other files taper away from the handle )
As bobl said a normal bench grinder is fine just don't get the file too hot go slow and dip the file into water often

Originally Posted by DJ's Timber

I have all the gear to do so.

Thanks for the offer Dj, it looks like I am in for a metal working lesson, with the taps and dies and the silver soldering. I will try to arrange a time to visit you before the plane making workshop.

Question were can I get non marring vice jaw pads? I have an old Dawn Vice that worn unevenly in the vice jaws pads.

Unfortunately there is probably as much to learn in metalworking as wood, and as you all probably know to cut joinery with hand tools requires some practice and care.

The whole first year of my apprenticeship 1 afternoon a week we cut loose with hacksaw and files to fit stuff. Once you have the skill you will be amazed and what you can do and how quickly and accurately you can do it.

I use wiltshire files. Probably not the best but they work ok. I'll offer two basic tips, may or may not help.

1. Files cut at a certain rate. Leaning on them won't speed the cut appreciably, it will tire you.

2. To file square holding both ends on the file and keeping it pretty square to the face particularly on the last few strokes may help. I'm not sure mind, because I do it by feel and I don't apply deliberate techniques like that, but it should help.

Brass is easy to cut. You should be able to get air tight joints without too much effort, but it does require some practice.

All my files from the smallest to large have a golf ball for handles giving me both comfort and control, the newer types do not have the horrible explosive centres the old ones had but I still drill the Golf Balls with caution.
Peter

I disagree with Jeremy's (jmk89) technique of holding the tip of the file in your left fingers to produce a straighter cut. I've had more consistent results by resting my left fingertip over the region being cut to apply uniform pressure. A flat piece of HDPE cut from a milk or juice bottle avoids filing the fingertip with the file's top surface. This is with a flat file, BTW. In either case, placing the surface at elbow height facilitates flatness.

Andy Mac's use of ink to identify high spots is akin to "blueprinting." Coat a reference surface, such as plate glass, with any colour actually, and rub it on the workpiece to transfer (or "print") to the high spots. File down the coloured regions. Several cycles may be needed.

Joe

TS,
if we get any spare time on Thursday I'll get you to have a go at a few things while we are in the workshop. Perhaps you could have a go at making a Cap Screw on the lathe or have a go at nickel bronze or silver soldering? Time...we need more of it.
Kevin

Originally Posted by thumbsucker

I have some basic metal working questions:

I am filling dovetails in brass, I am however a few problems with fillings out the dovetails.

1. What is a good brand of hand files, even Nicholson is now made in Mexico, how have peoples found these files?
2. Because the triangular files are serrated on edges, I find its near impossible to make a clean 15º without rounding the corners of my dovetails. I have read the suggestion on grinding away the corners on the files? How would I grind such hard steel - grinder? or can I get files with only on face that is the cutting face. Just like floats for making wooden hand planes.
3. Were can I get hardened steel angle in 200 mm sections? Without going out and buying angle, milling it and heat treating the angle? (Found a tip - using very hard steel angle in a vice I can used the angle as a guide to file the brass down to get straight edges on the dovetail bottoms)
4. How do you get a square edge in metal?
5. Anyone have any tips for techniques using hand files, like getting flat and square surfaces. I discovered that you can use the edge of the files like a hacksaw cutting into the brass

TS,

I spent the first 3 months of my apprenticeship filling a steel block cut from a piece of 2" square tool steel bar , fresh out of high school , I thought I was being tortured .The object of the excersise was to learn to file flat and square one face to another until we had create a cube with all dimensions within .005 " tolerance.It didnt matter what size the block finished at ,as long as all sides were square and flat and the thickness was with in tolerance on all sides
Once the block was completed to the apprentice master's approval we were given a piece of 3/4" thick plate 6" square into which we had to cut a square hole that the block would fit through with a .001" clearance.
I had blisters on my blisters and would go home at night in so much pain that I almost cried.My feet ached and so did my back , I wasn't used to standing on my feet eight hours a day in the one spot filing a mongrel piece of steel .
I still have that steel block it's on the bench in my shed ,I have carried it all over the country ,I used to look at it and curse it , but after all these years I look at it and just thank Christ I don't have to file any more of them.The square steel plate got used up along time ago for something else.


Hopefully I can pass on my experience to you in words ,much easier to show but hard to describe.
Nicholson and Wiltshire I think are now the same company ,I have both brands and some also made in India ,Sunflower brand or some thing like that .Some of my files I have had from when I first started my apprenticeship nearly 40 years ago.
I keep them sharp by immersing in cleaning vinegar for a few days and them scrub with hot soapy water and then spray with Inox or CRC then store them .When I want to use them I wash them in white spirit to remove the oil and them spray them when finished.
At today's prices I don't think you can get much better here in Oz.Also the types and cuts of files available has decreased .Some of the files I have are probably not available any longer , but an engineering toolmakers supply place may have some.

Saw sharpening files (slim taper triangular )don't have the sharp serrated edges but like three square files (normal triangular) they are 60deg angles so I'm not surprised you are having trouble getting into the corners and trying to file a 15deg angle .
Slim taper are available up to 7 " last time I looked ,I got all my saw sharpening files from Bunnings
My suggestion is to get a flat file say half inch wide and grind the edge away on both top edges to less that 15 deg.
If you grind files make sure you don't over heat them , toolmakers grind them all the time to suit, it's an acceptable practice .
For rough filing out the dove tails get a half round bastard file and grind the back off near the edges ,this will give clearance on the edges and sides of the dovetails but get you into the corners.
Then move to a smaller warding file to finish ,warding files are about 1/8"thick and flat ,and 6'' long grind the edges smooth so they don't cut into the sides .Even smaller files for final finish you can use needle files and even an ignition point file.
You can get files from engineering supplies with out the cut edges ,they are called cant files they are also used in saw filing.

To use a file correctly and to get flat faces and edges you need to hold the file flat through the whole stroke .To do this you move your whole body not just your arms.
If you push the file forward with just your arms you will rock the file causing it to create a convex surface from front to back on the work.
The stance you take with your feet is important ,place one foot forward of the other with legs slightly apart ,holding the file by the handle with one hand and the other end pinched between the thumb and pointer finger of the other hand ,( example :curl the fingers of your left hand a back into the palm with your thumb straight up like this
now bend your thumb down and clamp on top of your finger ,the file end should be between your thumb and finger.) Once you get the file in there you can open your other fingers out so you don't bark your knuckles on the vice or work.

Ok now with the feet stance correct , the file held correctly and placed on the work you move forward pushing with your body by moving the weight from the back foot to the forward foot holding the file and exerting some downward pressure with both hands .Keep the hand and elbow of the handle holding arm close to the body and in line with the file the other elbow cocked up to enable to exert slight down ward pressure on the other end of the file, you need to balance the pressure between the two hands so you dont tip the file forward or back ward .
You can compare the movement with that of using a hand plane ,if you use just your arms you will tire very quickly .Use your body weight to create the force you need to make the file do its job.

Files cut on the forward stroke only ,so you need to lift the file on the back stroke, just like a hand plane.Drag a file backward and it will dull in no time.
On a flat surface you would also move the file in a cross cutting action one stroke left one stroke right watching the pattern left on the metal to indicate where the file is cutting .You will see the scratches cahnge in direction with each stroke.
Another very important factor is the height of the vice and the work ,if it's too high you will rock the file and also loose the advantage of your body weight .If it's too low you will also rock the file and create a curved surface.
My suggestion is to have the file held some where just above the navel about a fist and a half above .This is more a personal comfort choice , just get some scrap and practice until you get more proficient .You need to be comfortable other wise you cannot concentrate on the work and what you are doing and you will tire and get frustrated which will reflect in the work and also the amount of cursing and bellowing from the shed.

By the way if you use a guide made from hardened angle you will stuff your files very quickly.

Tips :
Check your edges regularly using a small engineers square.
Mark out all your areas with engineers marking blue and a scriber it stains metal better than any thing else and won't rub off .
Check your filing with a square as you go so you can adjust before you get to the line.

Chalk and a proper file card will help reduce pinning , a normal wire brush is not as good as a proper file card for cleaning.Remove any large pinning with a sharp pointed object like scriber or an awl.
Pinning is not such a big problem with brass as with steel.
For filing brass I would use a small 1/2 round bastard file for roughing and then switch to a second cut as you get closer to the mark, finish with a warding file .Consider getting a junior hacksaw to cut out most of the waste (youre probably already using one ) and use the files to finish .

The less filing the better.


I hope this helps

My understanding of metal dovetail plane construction is that the dovetails are made oversize to get them to fit together then the dovetails are peened with a hammer until the metal flows into the voids and corners until the gaps all close up.
If this is the case then they don't need to be super accurate in fit ,just have nice straight edges and angles .I have also read of double angled dovetails where the inside edges also are at an angle to the face of the foot and side plates.

Kev.

It's late I'm off to bed.