Thread: Arboga rebuild dilemma

Hello all,

I purchased a little Arboga radial drill a few weeks back. It runs fine other than it's noisy. Opening the gearbox casing revealed why - 3 of the Tufnol gears have been replaced with steel gears.

I'm in the process of cleaning it up and repainting it so it's in pieces.

My question is, is it worth having 3 new tufnol gears made up? I haven't priced it up, but I'm guessing it'll cost a lot more than the drill itself cost me.

Thoughts?

Cheers
Jon

Jon, depends how much a quiet running drill is worth to you. The fact that you bought a high quality drill, and that you ask this question, makes me think that you would value well made and smooth running tools.

Any chance you can make the gears yourself? If you already have a lathe and/or a mill, all you need extra is probably a few involute gear cutters and a way to divide. Phenolic resin reinforced with cotton/linen cloth laminations (Whale, Carp, Tufnol, Bear, Crow, Resofil and many more trade names) is quick and easy and pleasant to machine, but fairly expensive to buy as plate or bar material. Still, it is likely that the savings over having someone make the gears for you, would pay for the phenolic, the gear cutter and a new rotary table together. Chris

When you get the new Tufnol gears, I'll take the steel ones off your hands.

Jordan

Hi Jon,

I'm interested how you know they were originally tufnol. I'm sure you are correct but just interested how you would know. Also, are you sure it's these gears making the noise and not the bearings? Just asking.

My geared head mill used to make a heap of noise. I found it quite distracting while working. When fitting the new motor for the VFD conversion, I took and chance and replaced all the Chinese bearings with better quality bearings. I also replaced the lower drag zz metal shield bearings with 2RS (rubber shield) bearings which increased the friction and drag but reduced clunky clunk backlash and slop when running. In doing so I reduced the noise by considerable amount.

Other option is to experiement with different viscosity oils. Just thoughts....

I suppose you would ave you considered making the gears yourself if you could...

Cheers

Simon

Originally Posted by cba_melbourne

Jon, depends how much a quiet running drill is worth to you. The fact that you bought a high quality drill, and that you ask this question, makes me think that you would value well made and smooth running tools.

Any chance you can make the gears yourself? If you already have a lathe and/or a mill, all you need extra is probably a few involute gear cutters and a way to divide. Phenolic resin reinforced with cotton/linen cloth laminations (Whale, Carp, Tufnol, Bear, Crow, Resofil and many more trade names) is quick and easy and pleasant to machine, but fairly expensive to buy as plate or bar material. Still, it is likely that the savings over having someone make the gears for you, would pay for the phenolic, the gear cutter and a new rotary table together. Chris

Thanks for the reply Chris.

I've already got a rotary table (no dividing plates tho but they're cheap enough) but cutting gears has always come across as pretty daunting tbh.

I'll give it some more thought and do some more research on cutting gears.

Cheers
Jon

Originally Posted by simonl

Hi Jon,

I'm interested how you know they were originally tufnol. I'm sure you are correct but just interested how you would know. Also, are you sure it's these gears making the noise and not the bearings? Just asking.

My geared head mill used to make a heap of noise. I found it quite distracting while working. When fitting the new motor for the VFD conversion, I took and chance and replaced all the Chinese bearings with better quality bearings. I also replaced the lower drag zz metal shield bearings with 2RS (rubber shield) bearings which increased the friction and drag but reduced clunky clunk backlash and slop when running. In doing so I reduced the noise by considerable amount.

Other option is to experiement with different viscosity oils. Just thoughts....

I suppose you would ave you considered making the gears yourself if you could...

Cheers

Simon

G'day Simon,

According to the manual they are tufnol - 1 gear is steel, the opposing gear is tufnol. This drill runs a total loss lubricant system, and all the oil points feed the bearings, not the gears.

I've never cut or attempted to cut gears, but nothing tried nothing failed right?

Cheers
Jon

Originally Posted by cba_melbourne

Phenolic resin reinforced with cotton/linen cloth laminations (Whale, Carp, Tufnol, Bear, Crow, Resofil and many more trade names) is quick and easy and pleasant to machine, but fairly expensive to buy as plate or bar material.

If using Phenolic for gears they should be made from plate material as the laminations run the wrong way for gears (for best strength they need to run out radially and bar material is wound circumferentially).

However, inspired by Simon's success with a Nylon worm gear, it may be possible (if even just as a stop gap) to make some gears out of engineering plastic - while maybe not as strong as phenolic, it's cheaper and for a machine with a low duty cycle would perhaps last just as long.

Another option if you haven't got the equipment to cut them yourself is to trade a favour or two with another member. If you were in Adelaide I could probably help out as I'm probably going to be gear cutting in the next few weeks anyway

Michael

Hi Jon,
How wide are the gear faces, and what pitch are they? The worm gear for Simons saw may have worked ok, but it is a slow moving gear. My experience withe the acetyl change gears i made for the Mars tells me the gears wouldn't last too well VS the steel ones. Unless maybe UHDP or another material might be better than the acetyl.
What size RT do you have? once i have finished drilling the plates for my DH the plates i have for my 6" RT will probably never be used again, at the least you could borrow them.

Cheers,
Ew

Jon,
given that you have to make three different gears and you already have a RT, why don't you build yourself an electronic drive for the RT? No more dividing plates, cranking, counting etc and you can make any division at all....
I built mine about 3 yeards ago and SimonL just finished his.
Have a look at: World of Ward :: RotaryController to get you started. A very straightforward project.

Originally Posted by jhovel

Jon,
given that you have to make three different gears and you already have a RT, why don't you build yourself an electronic drive for the RT? No more dividing plates, cranking, counting etc and you can make any division at all....
I built mine about 3 yeards ago and SimonL just finished his.
Have a look at: World of Ward :: RotaryController to get you started. A very straightforward project.

Can vouch for that. A great little project.
Simon

Thanks for kind offer Michael - I'm in Sydney so it makes things a bit difficult

Ew - Again, thanks for the offer - my RT is 10". Gears are 15.1mm thick, as for the pitch I haven't worked that out yet. Work has been flat out. I can get Tufnol locally through a few places, I haven't priced it up yet but I'd only need 120x300 sheet to cut 3 gears from (gears are 100/94/82mm).

That electronic indexer for an RT looks fantastic.

I'll get some prices on some sheet, and try and work out the gear pitch and go from there. I'd probably need to buy some broaches and an arbor press to make the key ways too.

Cheers
Jon

Broaches for keyways are not cheap either.
Without wishing to rob you of a learning experience, if you prepared the blanks I could probably cut the teeth and the keyway for you. Provided you weren't in a screaming hurry all it would cost you is postage.

Michael

Originally Posted by Michael G

Broaches for keyways are not cheap either.
Without wishing to rob you of a learning experience, if you prepared the blanks I could probably cut the teeth and the keyway for you. Provided you weren't in a screaming hurry all it would cost you is postage.

Michael

Michael,

You're too kind.

I'm well aware of the costs of broaches, and I'm sure my wife would understand the full disclosure of divorce papers too, given she thinks i have an obsession with purchase of large and rather heavy machines

I'd be more than happy to send you some money for your time. I'll PM you if i can source some material that doesn't require giving up a kidney

Thanks again

cheers
Jon

There must be a reason the Tufnol gears were replaced with steel. It might be as simple as some klutz jammed the machine and it stripped a couple of gears or it might be the tufnol gears just were not up to the job.
How much are you going to be using this machine? Unless its going to be used all day, if it was was me I'd try and rig up some sort of oiling system to the gears, or if that wasn't possible, just put it back together with some moly grease on the gears.

bollie7

Originally Posted by Jon_77

I'd be more than happy to send you some money for your time.

Jon, as most of the long timers here on this part of the forum could tell you, we don't make these offers with money in mind - the time spent doing the job is offset against the possibility that one day the person helping out may need some help in return. Not necessarily from the same person, but in the spirit of what goes around comes around, when I help you out I am repaying some of the debt that I've incurred when others have helped me out. (I think I've been helped out by members from just about every state or territory in the country). Similarly if you felt that this places you under some obligation, you can discharge that by helping out others as you are able. (See Pay it forward - Wikipedia, the free encyclopedia)
One day it will all even out and in the mean time the world is a friendlier place.

Michael