Arboga drill refurb

[ScotDave]

Hi All,

I'm new to the forum and have little knowledge of electrical (or metalworking) matters and even less about spares stockists for old and obscure bits of machinery - so would appreciate any help

I've recently been donated an old and tired Arboga E100 bench drill that I'd like to return to working order for small projects using the original, internal motor if feasible. It has most recently run on the motor you see perched on top in the photo below but this is a later bodge.

This make is Swedish and pretty high quality, the name is still used in Sweden. They made a range of drills, this being the smallest. From reading around the web most of these drills were 415V 3 phase but I think this one is single phase 220V. The data plate is pretty worn but you can see the 220.

Also the casting at the base of the motor has holders for what I assume must be two brushes - none of the online other photos of other similar machines I have seen (of 3 phase machines) have this.

A plate on the side of the machine says it was supplied by a London Engineering firm.

I've begun to strip the machine down and seems in OK condition inside with all gears in fairly good shape. The original motor is still in place, it's pressed into and screwed to the casting. I've removed the armature and tested it with a multimeter and it seems fine. Next stage will be to remove the magnets/field coils from the casting and see if I can test them.

Assuming all the bits I have are working, I'd need to rewire it with a switch and obtain some suitable carbon brushes. I also need a chuck as there isn't one.

Grateful for any advice on suppliers of brushes, bits and pieces or any expert advice on why what I'm planning isn't a good idea or just plain wrong!

Many thanks
Dave

 

[dickm]

Looks like a super machine. Good luck with the refurb. I just MIGHT be able to help with brushes, as bought a whole cabinet of them from closing down of domestic appliance repairer. Wd need to know dimensions and it's a long shot, but happy to try to help.

 

[DennisCA]

Lucky you, arboga is top notch quality from what I am told. Heimlaga should be able to help more with this, as he owns an arboga too.

EDIT: I notice it says LIKSTRÖM on the plate, that's swedish and means direct current. Did it perhaps come with a DC motor?

 

[ScotDave]

Hi Guys,

Thanks for the replies and the potential offer of some bushes - much appreciated Dick.

Yeah, thanks Dennis I was looking for Likstrom drills for ages - until I realised it was not the make! This is where my electrical knowledge or the lack of it lets me down. It's possible it's a 'Universal' motor that is DC but can accept AC or it's a 'normal' DC motor that won't accept AC. How would I know the difference without fixing it and plugging in? There's a snip from a Google search below. If the rest of the motor checks out OK then it would suggest it's DC I guess otherwise why would they bodge a new motor on top?

"universal motor" and is a bit different. These were specifically designed for small portable power tools and household appliances where variable speed / high torque was needed but AC was the primary supply source. Technically the motor inside is a DC motor because a DC motor gives you that ability to vary the seed easily (without inverter technology that didn't exist 50 years ago). But there is a rectifier built in to the motor, so you can apply AC to it. So you bring in AC, it goes through the switch as AC, then through the rectifier, then (typically for a drill) through another switch that changes drection, then to the DC motor through brushes."

PS If it's DC only motor why would it be sold in the UK? One theory someone mentioned is that its converted for say a ship where DC current might be generated but I don't know.

Cheers
Dave

 

[MusicMan]

I have a larger Arboga miller/drill and they are excellent machines. Mine is three phase so I can't help on the motor. If it is similar to the bigger ones, note that the gears are tufnol and should not be lubricated. Very handy having the "switchable' gears for the speeds.

Keith

 

[woodpig]

I read years ago that quite a few Arboga mills have gone to the scrappy due to having internal motors fail together with other non standard parts going missing/breaking/wearing badly. Have you got a chuck to fit it?

 

[ScotDave]

I read years ago that quite a few Arboga mills have gone to the scrappy due to having internal motors fail together with other non standard parts going missing/breaking/wearing badly. Have you got a chuck to fit it?

For sure, I guess there's a lot of old machines with no spares of all makes gone to the scrappy but a name that's not so common here is probably going to be more of a challenge than a UK make. No, there's no chuck, believe its a No.4 MT, so should not be a problem.

 

[DennisCA]

I have to say I have no idea why there would be a DC motor, there are many different types of DC motors but I am no expert on that. I have not been able to find any info on an arboga with a DC motor either.

I suppose the internal motor might have broken, or they did not have access to 3-phase power because it's england so they retrofitted a DC motor instead?

I don't know if what says on the plate refers to the original motor that the Arboga came with from factory, or if it refers to the new motor on top? The motor on top could just be a simple AC induction motor for all I know, not enough pictures to judge from.

Here's a swedish forum were someone restored a similar arboga drill, using google translate maybe it will make some sense to you:
https://www.maskinisten.net/viewtopic.php?f=124&t=16339

 

[DennisCA]

I found another thread with the same plate as yours, but more readable, it does seem the DC motor is the factory motor, what's on top might then be something else (bottom of page for image).

https://www.maskinisten.net/viewtopic.p ... &start=105

 

[ScotDave]

Hi,

Thanks, yes I joined that forum last night - there are quite a few Arboga machines. i started a thread there and will PM the guy with a similar machine.

Yes the motor on top is an AC motor and has been added later - it just lifts off. The drill works with this but I would rather use the original motor if it can be made to work. The original DC motor is pressed in to the cast housing as in the thread you linked to. It's quite unusual. Why anyone would buy the 220vDC version I don't know - most were 415v 3 phase. Still, it's interesting to find this stuff out!

Thanks for your help
Dave

 

[woodpig]

Small amount of information here:

http://www.lathes.co.uk/arboga/page2.html

 

[dickm]

Myfordman is your expert here - wait around and something might rub his lamp so that he will appear!
Don't know much about motors, but might having a DC motor allow some speed control?

 

[adidat]

Thats some piece of kit!!

Adidat

 

[CHJ]

If the 220 volt DC motor is still in viable working condition it's not too difficult to supply it from the mains via full wave bridge rectifier setup mounted on suitable heat sink in a local insulated case. (it would appear to be a fixed speed shunt wound unit)

Mains rated Solid state rectifiers capable of passing I.7 amp are readily available, although it would be wise to double or treble the current rating to cater for start surges or motor stalls.

 

[ScotDave]

Thanks for the posts - yes it's quite impressive isn't it?

I think it's quite feasible it was made for the UK market when DC mains power was still around. Web search suggests DC mains was still around in the 1950's when this thing was probably made.

 

[ScotDave]

If the 220 volt DC motor is still in viable working condition it's not too difficult to supply it from the mains via full wave bridge rectifier setup mounted on suitable heat sink in a local insulated case. (it would appear to be a fixed speed shunt wound unit)

Mains rated Solid state rectifiers capable of passing I.7 amp are readily available, although it would be wise to double or treble the current rating to cater for start surges or motor stalls.

Thanks that's the information I need. Can I purchase something off the shelf or does it need to be made?

 

[heimlaga]

DennisCA sent me an e-mail....so here I am.

Your drill is an E100 which is a good bit older than my Arboga G2508 and mine is the only one I have ever rebuilt so I cannot help you very much.
I think yours should have a Morse 2 taper and it may also have had a set of losse gears kept inside a round tin cover on top of the pillar. You cold choose which two speeds you wanted to have in your machine by picking the gears you wanted and mounting them inside the gearbox. Most E100 had this feature though not all. There was a special designation letter on those that didn't.
One side of the gearbow cover is easily removable by undoing the 4 big bolts and maybe a fifth small screw hidden in front (memory is blurry).

Arboga and Solberga and Strands competed between them over who made the best small drillpress in the world. All three claimed to be best and every owner claims that his drillpress is the best. Reality is that they all three were very good with no significant differences between them.
Ever though yours is an old, primitive and rather cheap version of Arboga it will still be better than anything you can find from anywhere else than those three Swedish makers.

Machinery Scandinavia AB is the name of the company that formed when Arboga and Solberga and Strands merged. They are still in business and produce modern decendants of your drillpress. The factory and the company headquarters are in Rosenfors in Småland in Sweden.
They still supply spare parts for many old drillpresses. I had no problems getting a new quill for mine some 5 years ago. Yours is a bit older so they may or may not have parts for it but it is surely worth a try if you need any.
http://www.mscab.se/en/startpage/

The built in motor is original. I would remove the botchjob on top. Unfurtunately many Arboga drills have been modified that way when the owner hasn't bothered to find out how to do a proper repair.
The worst thing that may happen to the built in motor would be an overload resulting in fried insulation inside the windings. You cannot always see that when measuring the resistance with a multimeter. If you hook up the motor to a Megger and crank it up you will find if there are any currents leaking anywhere. If that is the case I would seriousy consider having the motor rewound by a professional. When considering the prize of a new equal drill a rewind though expensive is mere pocket change.

I have never seen an Arboga with a DC motor and cannot comment on that. The plate clearly says "220volt direct current" in Swedish.

At least we know that the best benchtop drillpress on this forum resides on a Scotish bench. It isnae British aye?

Good luck!

 

[CHJ]

Thanks that's the information I need. Can I purchase something off the shelf or does it need to be made?

Should be able to get something suitable off the shelf:-
1. Rectifier
2. Heat sink
3. Plastic box to shield it

Start with something like this or This which I found with a quick search there are no doubt many other options.

No doubt Myfordman has recommendations that may help, my 'surplus' stocks are mostly orientated to low voltage high current stuff.

 

[Racers]

Don't forget that 240V mains it the RMS, voltage you need to multiply it by 1.414 to get the DC voltage so its 339V DC you would have to use a transformer to drop the voltage to 155V RMS to get 220V DC.

Pete

 

[ScotDave]

Thanks Chaps, I think I need to aknowledge my skill and time shortage here! If I could buy a plug and play box that would enable the DC motor to be used I'd fix it but as it needs to be built from components and that's a whole new skill set I do not possess and one probably not best acquired tinkering with mains voltage!

I also want to get the thing working so I can use it soon! So perhaps short term this prince of Swedish drills will need to continue to live with the indignity of being mounted by the AC British Crompton motor. I suspect the DC motor is fine but was bypassed once DC power became obsolete in the UK.

Alternatively if someone knows of a skilled individual or retailer that supplies the rectifier/transformer I need or would do the work for a reasonable fee please let me know. I'd also need to figure out a wiring diagram for the internal wiring of the motor as the have been removed at least in part so any volunteers for this on the same basis welcome. Failing this it's a retirement project so has at least another 15 years to wait!

I will also contact the factory to pick their brains about spares. An original 415v 3 phase motor is a slim possibility I suppose.

On the morse taper, I need to check if it's 2 or 4 as I am not sure which is correct and both have been suggested.

Thank you all very much for your input so far, it's all much appreciated.
Dave