Bradson hand pillar drill restoration

[MusicMan]

I have got distracted from this project by illness and other things but will post more when I get back to it.

The 2 speed mechanism works by engaging the upper or lower bevel gear. There is a lever to position it in either place.

It does all need to be aligned and tightened correctly for the device to work properly.

Yes it is cast iron, and I would not risk heating it (distortion possibility, and fire risk), but I learned from this thread that BLO (boiled linseed oil but not really boiled!) gives a very nice, similar finish. Not to be used on cookware, though!

Keith

 

[Wildman]

I like it in its bare cast. What kind of age would that be then? I've always fancied one of those high precision drills which run off a little flat belt.

they were still being sold new in the 1960's as my school was a new built with all new gear and we had one.

 

[MusicMan]

Back on the Bradson this week after much distraction and some illness. Gave it a general cleaning, BLO and Renaissance wax treatment. Looks OK but still not decided whether to repaint. First priority is mechanical functionality. Checking the operation of the drill with runout measurement:

There's a visible runout, which measured at about 0.4 mm. Not too good! Dismantled the spindle (yes, not needed to touch the square-ended nuts), just needed to undo the screw advance mechanism at the top of the machine. After cleaning the slot so that the key would run through all the way, this came off easily, then the spindle can drop through the rest of the assembly. Then mounted the spindle in the old pre-war Boley, with newly-acquired-and-refurbished fixed steady. I had to buy another lathe ("not running or for spares") for this hens-teeth accessory. Well worth it, as I took the steady and a couple of change gears and cannibalised the tailstock, and sold the rest on, so didn't cost me much and greatly improved the lathe. As you see, there are still three knurled knobs to make to replace the previous bodges.

First job is to clean up the rather battered spindle. Honed by hand with medium, fine and very fine stones seen below:

with a quite nice result:

Now for the top end thread. As mentioned above, with just the battered part projecting it looked like a square thread! But on seeing it all, it turned out to be standard 3/8" BSW. A former student recently gave me some nice BA and BSW taps and dies from her late father, and it cleaned up nicely.

Spinning the spindle slowly in the lathe with the thick part running in the steady and pushing at the thin end with the cross slide (using a flat brass pusher) straightened the rod fairly well. A bit of manual pushing with the lathe off fine tuned it well enough. This and tightening the final bearing (plain split cast iron) that the quill runs in brought the runout acceptably low, well below 0.1 mm.

Now for reassembling the thrust bearing and fine adjusting the stack for the autofeed. The shaft aligns and runs well now, but this is what was left inside the thrust bearing:

Not a surprise then that the autpfeed wasn't working too well.

I think it needs a few more than two balls! Fortunately, the grooved races and the outside surfaces are in good shape.

So, 5/32" balls, 3/8 BSW machine nuts and washers now ordered. This should be the total refurb cost, £7.62 including postage.

To be continued when the bits come....

Keith

 

[Kadushu]

Great thread! It's lovely to see old tools and machinery being looked after and put to use.

 

[Benchwayze]

I am so jealous, have wanted one of these for ages! There is one in my local junk shop, but they want £110 for it :shock:

I have often wondered how 2 speed mechanism works, as the only one I have had real life access to (above) was completed seized up so wasn't very enlightening. I look forward to more posts on this one

I assume the cast bits are iron? I have often wondered if cast iron tools could be finished in the same way as cast iron skillets by baking them in vegetable oil. It provides a pretty good all round finish on the pans and I cannot think why its wouldn't work on tools... would the heat damage them (170 degrees C)?

I would do my best to buy it. You won't find another one popping up soon, and if you do, well it will probably be twice the price! Just a thought, 8)

 

[Rhyolith]

I am so jealous, have wanted one of these for ages! There is one in my local junk shop, but they want £110 for it :shock:

I have often wondered how 2 speed mechanism works, as the only one I have had real life access to (above) was completed seized up so wasn't very enlightening. I look forward to more posts on this one

I assume the cast bits are iron? I have often wondered if cast iron tools could be finished in the same way as cast iron skillets by baking them in vegetable oil. It provides a pretty good all round finish on the pans and I cannot think why its wouldn't work on tools... would the heat damage them (170 degrees C)?

I would do my best to buy it. You won't find another one popping up soon, and if you do, well it will probably be twice the price! Just a thought, 8)

I was wrong, its £130 :shock: Sorry i just cannot afford that... As long as it does not become a garden ornament i am happy to just have seen one... drives me nutty how so many people leave these outside for such purpose with absolutely no suitable finish to protect them then throw them away, because surprise surprise, they rust up :?

 

[AndyT]

MusicMan

That's a cracking job there - precision therapy for a good old tool.

Rhyolith

I do wonder... if you went in at the right time, and had a chat to the junk shop owner about the sort of restoration you'd do, and your enthusiasm for these old drills, might you get it for a lot less? If nobody has bought it at the asking price, it's earned the shopkeeper nothing. You can explain that you normally never pay more than £25... :lol:

Wildman,
To prove you right, here's a catalogue listing from 1957 for six models of hand powered bench drill, two of them from Bradson. (Mind you, the same catalogue has six pages devoted to electric drills, from Wolf, Black and Decker and Bridges, so the end must have been in sight by then.)

 

[MusicMan]

Hi - I'm new to this forum, which I found while looking for help with my Bradson no.5.

I was given this beautiful machine by a friend who has great faith in my ability to bring it back to its former glory. Unfortunately, apart from the over-painted finish which needs dealing with, there is a slight bend in the threaded shaft of the chuck. Can anyone point me in the right direction for information on how to go about stripping the beast down, so I stand some chance of getting the threaded part repaired or replaced?
el
Thanks a lot, hope the festivities have been good to you all!

Hi Hedgewolf, welcome!

Removing the spindle is quite easy. Unscrew the nuts at the top of the spindle and it drops through and comes out from the bottom. On its way through, take off the thrust bearing race (warning!! The ball bearings are loose and will run all over the shop if you don't realise this in time!) and the two bevel drive gears and their washers. put them on the bench in order so you know which way they go back. If you clamp the base of the drill to the bench, you can rotate the top part so that it is overhanging the edge, which gives you room to extract the spindle. Be careful not to drop it, though. There is no need to remove the hand drive wheel or the driving bevel gear, or the depth advance wheel at the top of the drill if you don't want to.

There is a lot online about straightening spindles. I advise the pure mechanical methods rather than those involving heating. However, I have the gear and am not far away, in Warwick. The lathe and fixed steady were very useful for this spindle design. If you'd like to bring the drill over one day (I'm retired) we could do it in my shop. It would be interesting to see another one. And to meet another maniac/enthusiast!

Keith

 

[Rhyolith]

Rhyolith

I do wonder... if you went in at the right time, and had a chat to the junk shop owner about the sort of restoration you'd do, and your enthusiasm for these old drills, might you get it for a lot less? If nobody has bought it at the asking price, it's earned the shopkeeper nothing. You can explain that you normally never pay more than £25... :lol:

Its one of those shops where the stock is all from different dealers, so it does to depend somewhat on the individual. Unfortunately I know the place quite well and have had past dealings/attempts at dealings with the dealers in it who only seem to care about money :roll: , they are not generally pleasant to deal with and annoyingly they seem to get away with selling things at ridiculous prices.

The drill has been there for a while. So if its still there in the summer (when I am next back in Norfolk) i might have a go... but i cannot see it going below £90 even if play the restoration card (as they just don't care unless its going to make them more cash). I would only even consider it below £50.

 

[MusicMan]

Yes, I paid £50 for mine, on eBay. Be patient as they do come up regularly. Only rubbish there at the moment as far as I can see.

 

[Rhyolith]

I am trying to understand what you have done to the spindle on the lathe (sorry my reading is not great), straighten it I assume? Wouldn't that make it thinner? (and thus wobble). Also whats that guage in the first picture that is riding up against the chuck assembly?

Good post

 

[MusicMan]

I am trying to understand what you have done to the spindle on the lathe (sorry my reading is not great), straighten it I assume? Wouldn't that make it thinner? (and thus wobble). Also whats that guage in the first picture that is riding up against the chuck assembly?

Good post

Thanks. I didn't remove any metal from the spindle apart from surface bumps (that was the honing with fine stones, which would not have made it significantly thinner). I bent it straight(er). The thick part was not bent, and was held at each end, chuck and fixed steady. This part ran true, then you could see the free end of the thin section wobbling.

I used two methods to straighten it. (1) push a blunt plate (brass) against the wobbling end, using the cross slide. It's easy to see when it runs true, then push a bit more and it sets permanently. Easy to overdo it though. (2) rotate by hand till the high spot is against the bar in the cross slide, then use the cross slide to push and straighten it.

There is also a technique used by musical instrument repairers on thin rods (usually 2 - 3 mm), which I might try if it needs improving. This uses a hole a bit bigger than the spindle, drilled across the end of a piece of wood, traditionally a hammer handle . Spinning the lathe slowly while drawing this piece along the work, applying a twisting pressure, works well. It's discussed at http://forum.saxontheweb.net/showthread ... aightening.

The gauge shown in the figure is a digital displacement gauge (digital form of dial indicator) with 0.01 mm sensitivity. I like this one as it has quite a long range. With the sensitive dial indicators, the range is often small, so I am forever jiggling it about to get the eccentricity within the range of the gauge. The measurement is called Total Indicator Runout or TIR. The spec on a hand drill is usually about 1 thou or 0.025 mm. I'm just about to check this carefully.

Keith

 

[MusicMan]

Not really happy with the spindle straightness so had another go. The main issue using the steady was that the milled alignment slot in the spindle messed up the perfect holding in the steady. So I made a sleeve to bridge that gap, with a light interference fit onto the spindle. This was a big improvement. I also used the four-jaw chuck, well aligned.

Now I could measure the deflection and tell where it was maximum. The spindle was held firmly in the steady so I just pushed it straight, first by hand then with a hole in the end of a hammer. It's a little S shaped, but in fact there is plenty of clearance in the hole in the screw advance thread, so it should not interfere. Average straightness only is needed here! It got to about 0.1 mm. The overall precision is defined by the lower part of the spindle (nearer the chuck) and its bearing; this part simply has to rotate without catching in the screw advance hole.

Now for the chuck. Spindle reversed, aligned again in the four jaw. Quite a wobble seen, at least 0.5 mm!

But spinning it slowly and pushing a flat thing against it from the cross slide straightened it out very easily. Maybe too easily. I am not sure this will be stable and there may be something off in the chuck fixing. Will see that later.

The ball bearings have come, now to fill the race. Found some grease from my old motorbike days (that was 40 years ago!!) and packed the race, leaving a gap of one so they don't fret.

Doing it in a tray to stop them migrating round the shop...

The race now runs smoothly. Now inserting the spindle from the bottom, with the top assembly lifted as high as possible. Washer, lower bevel gear, upper bevel gear, thrust race.
Locate in both the square-end bolts. Secure with a screw at the top (washer and another screw to come).

So here it is assembled again apart from the feed mechanism. Still have my doubts about the chuck mounting, but the bottom part of the spindle is good to 0.1 mm. As this is also the slop in the lower bearing even with the adjustment screw very tight (any tighter and it might crack) thats as good as I'll get at the moment.

We'll see how it works. In the end I might do a thin shim for the bearing.

So next is to assemble the advance mechanism and try to make it work ... oh yes, and see how it drills holes!

 

[MusicMan]

The spindle is now assembled. The amount of thread on the top of the spindle was rather short, and two standard nuts and a washer were too thin, so I turned them down on the smaller Boley (still has only 5 microns runout after about 80 years!).

The thin nuts look quite neat, when assembled as per Bod's instructions earlier in this thread (thanks again) and worked perfectly.

There is (as intended) zero rotation of the advance wheel when the drill is spinning, and the pawl advance mechanism when temporarily fitted works perfectly. It isn't fitted permanently as I seem to have lost the thick outer washer on the pivot for the cam. Oops. Search the floor tomorrow or make another!

And here is the First Hole!

BUT before contact the drill bit wobbled around like mad, though it was secure in the chuck. The chuck or its fixing/location/screw thread is not yet right. Maybe the missing grub screw. More later ....

I'm going into so much detail since i know a few others here want to recondition a similar drill, so I hope it may instruct them and entertain others .

 

[Chris Hammond]

I’ve just picked a Brandon 5 from an old blacksmith shop in Wooten-under-Edge. There were some lovely bellows and other beauties there but the development contractor insisted on throwing all out. Would not consider selling. Just can’t figure it.Anyhow I love my Bradson - so now to restoration.
I’m retired from mental health services and although I’ve always done my own woodwork and building, to my great regret I have no technical or engineering training. So I’m starting from a pretty low base.
Acquiring this Bradson is part of my project to abandon electric (where possible) for hand and eye in my woodworking. Hopefully I’ll acquire some basic engineering skills along the way.
The Bradson is in pretty good nick in its original colours. I’m sure I’ll needs to replace a few small parts as I go - all to be expected. Ball bearings (the housing has come apart as the shaft has dropped), nuts and bolts etc. Can anyone recommend a supplier of old threads?
I’ve read everyone’s post a good few times. Really helpful everyone.
First problem: a very nasty lock nut (plastic type) has been jammed into the top of the advance wheel. I guess I should be able to prize it out as it’s not holding anything. Any advice warmly welcomed.

 

[MusicMan]

Well, we are all ready to help, but the condition is you have to provide pics! Especially of the lock nut and the locations of the missing nuts. Most of the threads are Whitworth. Find and keep all those ball bearings, yes they do drop out on disassembly. If you have lost any, they are easy and cheap to replace, but you should replace the lot not just one or two.

Look forward to hearing and seeing more.
Keith

 

[MusicMan]

PS how is the chuck? The main problem on mine is actually the alignment of the chuck on its shaft. I've managed to straighten the slightly bent shaft, but then decided to overhaul the lathe before tackling the chuck. Which got delayed by illness so it's all in a bit of a limbo!