drilling steel on an angle

[elementFe]

Can anyone out there walk me through the basics of drilling steel on an angle?
Making infill panels for a stairway- it seems no end of obstacles to drilling accurate, consistent holes on about a 34 deg. angle- wish I could just punch em!
My drill press is set for the angle, but getting it to actually drill in the right place without wandering to the side is baffling...
Thanks for any suggestions!
Andy G.

[Bob S]

try using an endmill.

Bob

[elementFe]

try using an endmill.

Bob

Can't be done with a drill press?

[Alec.S]

Though i have not done this wouldn't it be possible to drill a little dip just so that the drill wouldn't wonder so much then put it at the angle required and drill it.??

alec

[elementFe]

Though i have not done this wouldn't it be possible to drill a little dip just so that the drill wouldn't wonder so much then put it at the angle required and drill it.??

alec

Still haven't given up on that idea, but at 34 deg, it's hard to drill a deep enough dip.

[brian.pierson]

You can't punch a starter hole with a center punch? How many panels and holes per panel are you doing? If not many, would a dremel and ball cutter be possible to make the starter?


Just a thought off of my head.

Not a professional so maybe I am missing something obvious.

Brian

[used-iron]

Make and harden a drill guide. clamp in place and drill. a fancy one would have different size hard bushings. as stated before an end mill will give you a flat landing for the drill. in a pinch grind an old drill back close to 90deg,its hard on the drill corners,once you get a flat then switch over to a regular drill.
Lee from nys land of taxes

[welder19]

I will normally start with a hand drill, center punch where you want to drill, then start drilling straight and gradually angle the drill as it drills till you get to the approx angle you want then move to the drill press to finish.
The end mill will work too, even in a drill press.

welder19

[elementFe]

I will normally start with a hand drill, center punch where you want to drill, then start drilling straight and gradually angle the drill as it drills till you get to the approx angle you want then move to the drill press to finish.
The end mill will work too, even in a drill press.

welder19

Thanks for the ideas, since there are only a few pieces (four for one stairway and four for another, six holes on each) I was looking for a quick and dirty workaround- playing with test pieces showed me one thing for sure: can't have enough oil on it!
Also, thanks for the end mill idea- having never used a milling machine or lathe, I'm a bit slow understanding, but that's a great idea.

[Sam Thompson]

What about cutting the ends of the bars to the correct angle and tapping them to take a screw at 90' to the rails?

[Nakedanvil - Grant Sarver]

Large number of holes use a drill jig and a drill bushing, still want to use an end mill. For a few parts then end mill with the part well clamped and a slow feed should work great.

[elementFe]

What about cutting the ends of the bars to the correct angle and tapping them to take a screw at 90' to the rails?

Good solution, except these are 1x1.5 flat bar with 1/2" CR round passing through.

[elementFe]

Large number of holes use a drill jig and a drill bushing, still want to use an end mill. For a few parts then end mill with the part well clamped and a slow feed should work great.

OMW to the store to buy a 1/2" end mill. Any hints on how to center it on the punch mark? The outside edge of the cutting surface will kind of hit "out there somewhere" it seems

[Jocko 58]

G'day i would use a centre drill works for me that's if you are useing a drill press

[John B]

Can anyone out there walk me through the basics of drilling steel on an angle?
Making infill panels for a stairway- it seems no end of obstacles to drilling accurate, consistent holes on about a 34 deg. angle- wish I could just punch em!
My drill press is set for the angle, but getting it to actually drill in the right place without wandering to the side is baffling...
Thanks for any suggestions!
Andy G.

Here in the UK, End mills (Solid cored multi flute tool) are good for spotfacing and machining using the sides of the mill, but not designed to cut through solid metal,
If you are going cut through or on an angle you need a slot drill which is two fluted like a flat bottomed drill in appearance, but with the flat cutting face having an offset centre allowing you to plunge cut a hole through solid material.


You can punch through on an angle hot by making a fixture to hold the bar and punch at the required angle, whilst punching through the bar with a square ended punch, these can incorporate an indexing feature to ensure repeatability of centres.

You don't say why you need to use punched holes, do you intend to rivet the uprights in?

If you are you will have to make shouldered tenons on the bar ends.

Instead of putting a straight tenon with an angled shoulder on, (If you punch the hole on an angle it will have to have an angled shoulder on the uprights to fit properly) forge an angled bend on the ends of the upright bar at the required angle, then forge the tenon round to fit through a round hole punched in the base/top rail, in effect a very short standard straight rivetting job.

This method also works well to fit straight uprights into bow topped gates/panels etc. the distance for the angle bend can be longer from the tenon shoulder on these

[Frosty]

Though i have not done this wouldn't it be possible to drill a little dip just so that the drill wouldn't wonder so much then put it at the angle required and drill it.??

alec

Yes Alec, this WILL work if you grind the bit so it's angle is close to what you want. In Andy's case that'd be 34* per flute.

Andy, I was going to suggest this but there have been plenty of workable suggestions on Theforge list.

Can you heat the stock? If so a large rounded center punch will easily make a nice round punch mark at an angle for you. Or you can grind an obtuse angle on a center punch and still leave a point to make positioning easier. 34* in this case.

The suggestion of grinding a shelf at 34* and punching to start the drill is a good one, especially if you have either a table saw or Skill saw. Simply put a cut off blade in the saw, set it's angle at 34* use an independant gage, NOT the one on the saw! Sorry, right now I can't remember the tool maker's compass type square that'd I use to make a gage block.

Anyway, set the angle of the saw blade, then set it's depth so it's deep enough to seat the drill bit, I'd say 1/2" minimum. Then saw the bar at the point(s) you want the hole(s, then if necessary turn it around 180* and cut the angled bit out of the way so the drill bit seats cleanly. Center punch and drill using an angle vise or angle the drill press table to 34*.

The drill guide block suggestion is a perfectly workable one too and you can use the table saw to cut it to 34* so you won't have to do a lot of grinding, filing, sawing, milling, etc.

I think I'd use one of these myself if I didn't have an end mill and I don't so . . .

Frosty the Lucky.

[John B]

OMW to the store to buy a 1/2" end mill. Any hints on how to center it on the punch mark? The outside edge of the cutting surface will kind of hit "out there somewhere" it seems

If you are going the slot drill/end mill way, you dont have to pick up on the centre mark, as you are going on an angle the corner of the tool will cut first, so, mark the edge of the hole on the centre line and touch that with the cutting corner, the pitch will be the same, just mark the first hole centre in the correct position and then come up the 1/4"plus a bit (Math can be useful to determine the exact size) to allow for the tool cutting on the required centre line (if that makes sense)then the next touching mark will be your required hole centre pitch

Or in simpler terms use the hole edge as a guide mark rather than the centre mark

You don't have to go all the way through with the end mill/slot drill, just make a pocket deep enough to allow all round support for a normal drill to be used to go through the majority of the material this pocket will act as a guide bush for the drill

[Nakedanvil - Grant Sarver]

1 X 1.5? O.K. Good information about slot drills, don't see that term much in this country. Be hard pressed to find a supplier who knew what you meant. Cutting on an angle I'd be careful about a two flute grabbing at the start and at the "break-thru". In any case it should be a "center-cutting" tool.

[John B]

1 X 1.5? O.K. Good information about slot drills, don't see that term much in this country. Be hard pressed to find a supplier who knew what you meant. Cutting on an angle I'd be careful about a two flute grabbing at the start and at the "break-thru". In any case it should be a "center-cutting" tool.

Hi Grant, if you use the slot drill, its flat bottomed so is designed to cut vertically into a surface. (Keyway slots, hence the descriptive name and they hold a tight tolerance)

In practice on an angled face it acts like a fly cutter or boring bar in a lathe, so it starts cutting with a sharp edge immediately on contact, and so does not'grab' they do like a steady mechanical feed though, but can be used with care by hand

[John B]

Hi Grant, if you use the slot drill, its flat bottomed so is designed to cut vertically into a surface. (Keyway slots, hence the descriptive name and they hold a tight tolerance)

In practice on an angled face it acts like a fly cutter or boring bar in a lathe, so it starts cutting with a sharp edge immediately on contact, and so does not'grab' they do like a steady mechanical feed though, but can be used with care by hand

If you google "slot drill" and look on wikipedia there is an illustration where you can see the offset two flute end of the slot drill, compared to the end mill and ball nose cutter

[Judson Yaggy]

Slot drills- THATS what those are! Got some in a lot from an auction a while back and have been wondering ever since. Thanks John B!

[arftist]

Lot of ideas here, but to clarify a little, here is exactly how I do this. With the head set over to the required angle, I spot face the stock with a center cutting four flute endmill, for any metal but aluminum or brass. For the aluminum, a 2 flute works better, and for brass either will work, but a two flute is faster. The spot facing operation only proceeds to the point that there is a sufficiently sized flat (perpendicular to the angle of the spindle) area to start a drill bit. The end mill is then swapped for a drill bit, and drilling proceeds. In the case of an angled hole in pipe, or tube, round or square, a center cutting end mill only is used, no drill bit. This can be done on a drill press or a vertical milling machine, however, the work must be clamped securely or held in a vice bolted to the table.

[BIGGUNDOCTOR]

Get a center drill (combined drill, and countersink in some catalogs),a #5 or #6 has a 1/2" shank. These drills are short, and stiff, keeping them from walking on you. I use these all the time at work for angled holes. The center drill will get you a pilot hole made which you can follow up with a regular twist drill.

Endmills in a drill press. Depends on how little runout you have in your spindle, and if your chuck can hold onto it with out it slipping. Too much runout, and it will be a bear to make a clean hole. As Grant mentioned earlier, the endmill will have to be a center cutting model. A 4 flute is usually smoother when plunging. To center on a center punch mark, just put a pointer, or drill in the chuck first, and use that to establish center.

It doesn't matter what you use, the main thing is a rigid setup. None of this will do any good if the whole shebang is wiggling all over the place. Keep distances to a minimum, and clamp everything tight.

[monstermetal]

So I am no machinist and am a little lost on the "slot drill" I looked at wiki and what they label as a slot drill I would call a center cutting 2 flute end mill... Is it just a terminology thing?

[John B]

So I am no machinist and am a little lost on the "slot drill" I looked at wiki and what they label as a slot drill I would call a center cutting 2 flute end mill... Is it just a terminology thing?

Slot drill was the name for it in the UK when I served my apprenticeship way back in the mid last century (Thanks for reminding me about that detail, may have to change my description to 'Old Fossil' now)

Other locations may well know it by other names,

As for the 4 flute end mills, (some may have more than 4 flutes, the numbers of flutes also alter with sizes but to quote Biggundoctor "A 4 flute is usually smoother when plunging" I personally have never come across one that you can plunge cut into solid material as the end is flat, with a slight recess in the centre that governs how far you can cut vertically into the material,and the centre of the tool is solid, and so will bottom out when the tooth depth of the cutting end is reached, smoothness of cut can also depend on rates/relationships of speeds and feeds, sharpness and cutting angles on tool's edges, materials being cut, and rigidity of workpiece and tool mounting.

On a further point as to names of tooling here in the UK, again Biggundoctor mentioned "Get a center drill (combined drill, and countersink in some catalogs),a #5 or #6 has a 1/2" shank. These drills are short, and stiff, keeping them from walking on you I use these all the time at work for angled holes."

We call these Combination centre drills, but originally they were known as Slowcombe (Slocum) Drills,

To Quote again "The center drill will get you a pilot hole made which you can follow up with a regular twist drill" and they are perfect for that, however take care as the small diameter end portion is prone to breakage.

These combination drills were more commonly used on lathes to assist supporting longer pieces of work being turned.

They will also produce a chamfered (Angled) front to the hole, this angle is the same as the angle on a lathe centre used in the tailstock of the lathe, the pilot on the drill allowing the centre to clear the end of the lathes tailstock centre, this allows the piece to be securely supported at the end some distance from the lathe's chuck whilst turning long parallel lengths, a steady (travelling or fixed) can also be used to aid rigidity throughout the cut being taken.

By definition an end mill is for milling/machining flat areas then you get other types of cutters, slab mills, side and face cutters, slitting cutters, dovetail cutters, T slot cutters etc, the clue is in the name, hence slot drills are for "drilling" into materials to the full depth of the flutes on the tool, and mills are for milling areas.

We are travelling into the realms of engineering now and most people do not have the machinery available to use these types of tooling correctly, it is also fairly expensive to purchase new, and need to be used with care to be safe.

However Blacksmiths were the forefathers to the Engineers, and this type of joint was being made before machinery was available, but this application that the original question was posed about may be a finished welded application as opposed to a forging problem.

I look forward to seeing pictures of the finished project as I am intrigued by the sizes/types of materials stated as to finished proportions, methods of assembly etc. If the 1" x 1.5" is solid, it is going to be quite weighty.

Thanks to Biggundoctor for his prompts, and apologies for the long windedness of the post