# Restoring a Vintage Saw



## Mark A

Hi chaps,

How can I extract this gear? There's a smidgen of forwards and backwards play on the shaft, so I reckon it's just a case of pulling it off - must be, because there's no other way to seperate the gear housing from the rest of the saw without removing the helical gear first. 


















Cheers,
Mark


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## Mark A

Forgot to add I don't possess bearing pullers etc.


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## Monkey Mark

Without pullers you may well struggle.
If it was me I'd place the shaft into a vice protecting it with soft jaws/rubber/similar and gently tap the body.

Edit: hard to tell from the pics but it looks like there could be a reraining bolt/grub screw on the outside of the casing holding the helical gear in place. If the bolt is removed perhaps the casing can be separated without removing the gear pictured?


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## Mark A

Monkey Mark":3te9vu81 said:


> hard to tell from the pics but it looks like there could be a reraining bolt/grub screw on the outside of the casing holding the helical gear in place. If the bolt is removed perhaps the casing can be separated without removing the gear pictured?



The bolt you are referring to on the right side is the threaded end of a shaft upon which the worm gear is fixed. It passes through a bearing and is secured with a nut. 

I've already tried pulling the casing away from the saw but it wouldn't budge. 

Mark


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## spinks

Could you drill and tap the gear (say m6 ish) and use 2 bolts and a small steel plate to pull it out?


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## Monkey Mark

What make of saw is it?


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## Graham Orm

Looks like it's a throw away to me, not designed to be replaced. I really can't see anything pulling that off.


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## Graham Orm

Can you get the worm gear out from above it? In the top picture I can just see the end of it.


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## rxh

What are the diameters of the hole in the tool body and the gearwheel (to the tips of the teeth)? Also, how far is it from the face of the gearwheel to the outer face of the hole?


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## Mark A

Many thanks for your help so far!



Monkey Mark":83q2ray1 said:


> What make of saw is it?


It's a Black & Decker "Ripsnorter" circular saw.



spinks":83q2ray1 said:


> Could you drill and tap the gear (say m6 ish) and use 2 bolts and a small steel plate to pull it out?


In theory I could as I have a drill press and a cheap tap and die set; though I really wouldn't like to in case I messed up.



Graham Orm":83q2ray1 said:


> Can you get the worm gear out from above it? In the top picture I can just see the end of it.


No, the only way to access the inner workings of the saw is to remove the helical gear first.

The motor turns the worm gear, which meshes with the bronze helical gear and transmits the power perpendicularly to the blade. Forcefully pulling the casing away from the motor would mean everything working in reverse and it doesn't want to.



rxh":83q2ray1 said:


> What are the diameters of the hole in the tool body and the gearwheel (to the tips of the teeth)? Also, how far is it from the face of the gearwheel to the outer face of the hole?


I'll measure it when I'm home a bit later today. What did you have in mind?



Graham Orm":83q2ray1 said:


> Looks like it's a throw away to me, not designed to be replaced.


No chance! :shock: It's from a time when things were manufactured to last and not thrown away when a fuse blows like we do today. The castings are a tiny bit rough in places, but mechanically it's very well made - even the lower blade guard has a thrust bearing to ensure it retracts smoothly...This saw is precious!


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## Graham Orm

Is it pressed onto the shaft or floating? You say there is slight movement.


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## woodpig

Without actually seeing it in the flesh it's hard to be sure but it's probably not designed to be taken apart so looks like there was little interest in making it easy to get the gear out. The manufacturers may well have had a suitable puller for it though. You may have to make up a puller if you can't buy one slim enough to do the job? Then again, getting the gear back on may not be straight forward either! Good luck with it though and let's here how it works out, it may be of use to others.


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## skippy75

Does look like you would have to make something just for the job. No normal puller would get in there.


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## CHJ

I would say that gear is trapped by the pinion, you need to dismantle the device enough to wind the pinion out of the gear (like a screw thread.)

That would explain the side movement, just the clearance play in the assembly.


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## dickm

A couple of things to note with worm/pinion pairs like that. When pulling the pinion out, it needs to be twisted slightly at the same time, as the teeth are not parallel to the axis. One other possible difficulty is if the pinion is not a cylinder, but "waisted" (bit like a squashed cooling tower) which makes it even more difficult/downright impossible, as the worm sits within the waisted bit and this stops the pinion pulling out. The rotor gearbox on the old Howard Bullfinch rotavator was like this, and from memory, it was necessary to pull out the worm, by effectively unscrewing it from the engine side.
It might be possible to do this if you can get at the armature to rotate it while pulling on the gearbox housing. (Aha - just seen CHJ has already suggested this). Further thought - where does the gearbox split from the motor housing? If it splits at right angles to the motor shaft, it might work to rotate the gearbox to unscrew it off the pinion.

But at that date of manufacture, it was almost certainly designed to be disassembled if wear had occurred. Maybe try asking on one of the US forums, where there seem to be folk who do this sort of thing routinely.


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## Mark A

rxh":njz87is9 said:


> What are the diameters of the hole in the tool body and the gearwheel (to the tips of the teeth)? Also, how far is it from the face of the gearwheel to the outer face of the hole?



Diameter of hole - 44mm

Depth of gear - 19mm

My digital calipers aren't able to reach the gear to give an accurate reading of its diameter, though it looks to be a smidgen less.

Thanks for the advice everyone - I'm in my garage as I type this trying out what's been suggested. 

Mark


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## rxh

This special puller I have is for a gear wheel of about 39 to 40 mm overall diameter and up to 20 mm thick. The diameter of the locking barrel is 47.6 mm so sadly it looks like it would clash with the hole in your case.


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## Graham Orm

I think as mentioned earlier you'll have to drill and tap the gear, if it will drill that is. A piece of thick flat bar with a bolt through it will work then. Just get your bits organised and take your time.


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## Mark A

Hi chaps,

I managed to separate the gear casing from the motor housing with a pair of wedges.





Almost 70 years worth of dust and leaking gearbox oil built up inside of the motor housing. It looks like a sewer!






Chas and Dick - You are both correct; on very careful inspection with a torch the helical gear is indeed waisted, so it must be removed after the worm. I tried unscrewing the gear from the casing by rotating the armature, but so far it hasn't worked. I'll search forums and youtube in the morning.

Thanks,
Mark


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## dickm

Mark A":wza5lr85 said:


> Hi chaps,
> 
> I managed to separate the gear casing from the motor housing with a pair of wedges.
> Almost 70 years worth of dust and leaking gearbox oil built up inside of the motor housing. It looks like a sewer!
> 
> Chas and Dick - You are both correct; on very careful inspection with a torch the helical gear is indeed waisted, so it must be removed after the worm. I tried unscrewing the gear from the casing by rotating the armature, but so far it hasn't worked. I'll search forums and youtube in the morning.


Nice to be proved right! A good job you didn't start drilling holes in the end of the pinion shaft and trying to force it out with a puller  . 
Is there any sort of collar or something on the end of the worm shaft that is stopping it coming out? The other possible (actually, thinking about it, it's a probable) is that the worm gear is actually pinned on to the shaft, and is too big to go through the bearing in the end of the motor housing, Can't *see* a pin in the pics, but worth a look.


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## Mark A

Hi chaps,

Good news! The worm is out of the box!

Here's a picture to prove it.






It transpires the shaft upon which the worm is fitted is splined, and so to disasemble it was just a case of knocking the shaft through. I had actually tried doing that a couple of days ago, but was just not heavy-handed enough as I was worried about cracking the casing or damaging a bearing.

I did, however, discover after taking apart the gearbox that a small chunck of casing around the rear bearing (through which the shaft passes) has come off at some point in the last 70 years and the rubber gasket has started to perish. The gearbox oil has been slowly seeping through, and is the reason why the motor casing is so filthy.

I have a tube of gasket sealer. Is there any reason why I shouldn't use some in conjuction with the perished rubber gasket?

Mark


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## dickm

Hope it wasn't your hammering that dislodged the bit of the casing (been there, done that!). 

Could you re-build that broken bit with epoxy? Presumably it doesn't take any stress? And re-make the gasket if you have the original as pattern and can identify the material.


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## Mark A

dickm":xzrnz5ou said:


> Hope it wasn't your hammering that dislodged the bit of the casing (been there, done that!).


Wasn't me, honest! 

The screws securing the stator are worn, which suggests the saw has been dismantled at least once in the past.



dickm":xzrnz5ou said:


> Could you re-build that broken bit with epoxy? Presumably it doesn't take any stress?


How would I do that? Build up layer after layer and then grind back with a Dremel? 



dickm":xzrnz5ou said:


> And re-make the gasket if you have the original as pattern and can identify the material.


I have some rubber matting which is about the right thickness. The original gasket isn't too bad; can I not just smear it with gasket sealer and be done with it?


I have a question about gearbox oil.
The original instructions for this "Ripsnorter" say to refil the gearbox with the official oil, but there are no more B&D service centres around. My "Tarplaner" came with a little tin of extremely viscous oil, and while searching online for worm drive saw gearbox oils I came across a forum post which suggested SAE 140. I have been using an EP80W-90 but I'd rather get it right. What do you think? 

Thanks,
Mark


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## CHJ

If 80-90 gear oil is good enough for a car differential I'm sure it will do for the light loads in a tool gearbox.

You are not after high performance, just something that will stay on the mating surfaces to prevent metal galling.

Most modern formula gear oils are a better performers than the older single viscosity spec. oils sold by tool firms under their own brands.


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## Mark A

Hi Chas,

Initially that was my thought too - if it's good enough for a diff etc. 

However, with both my "Tarplaner" and "Ripsnorter" after flushing out the gearboxes with kerosene and refilling with fresh EP80W-90 I noticed some seepage pooling below them. This is what made me then think about using a more viscous oil, as the manufacturers intended. 

Truth be told I'm trying to get out of replacing the gaskets...

Mark


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## Shrubby

To repair the gear housing degrease it thoroughly and build walls from plasticene to support the filler. Use a metal loaded epoxy like Devcon , Loctite or JB weld 
Hold the part in a vice or prop it up on a sandbag at the right angle whilst it cures
Matt


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## dickm

Exactly what I was going to say, Shrubby!  

W.r.t. to oil there used to be one called Hypoy which went into the diff housing of my elderly Volvos. Not sure what was the viscosity, but it might have been heavier than 80.

What do you see as the problem with replacing the gaskets, Mark? Material/shape/access? Gaskets are usually pretty straightforward.


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## Mark A

Hi chaps,

Thanks for the plastercine tip, that's handy to know!

Accessing the flange could be a bit tricky, however. 

Here's some pictures of the gearbox housing.






(this is looking at the flange from behind)

Chas - The original gaskets aren't just rubber disks or rings. See pictures below








The smaller of the two is the perished gasket which fits into the recess behind the broken flange. Here's a close up





Mark


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## Mark A

Apologies for the rubbish pictures, it's the best my phone can do!


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## CHJ

I would not refer to those as Gaskets, they are shaft oil seals, some at least spring loaded and should have a knife edge inner face bore against the shaft to reduce friction and provide a positive pressure enhanced seal against oil leaking along the shaft.

You should be able to find replacements, possibly at a bearing suppliers or motor factors, it's years since I've rebuilt engines so am out of touch with sources. I know Simply Bearings have some.


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## n0legs

They're Radial Shaft Seals.
A good engineering supplies should have them, if not as stock but could be ordered.
I doubt whether instant gasket/sealer would work against a rotating part.
Well built machine though, I can't imagine many being built like that these days.
Good luck


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## Mark A

Proves just how little I know!

Just found this company which looks promising, and as luck would have it I'm driving past tomorrow (collecting a dinky Myford planer) 

Cheers,
Mark


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## CHJ

When you refit any new seals of this type (or the old ones for that matter) make sure you replace them in the same orientation as originally fitted.
Their design is such as to increase the sealing force as face pressure is increased from heat/pressure expansion of the oil containing compartment.

Not so critical in a tool gearbox perhaps but it is best to make use of the 'self closing' aspect of the design where possible as wear takes place over time. (don't think that will be a problem in our lifetimes in this instance though  )


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## Mark A

Hi Chas,

I dropped the oil seals at the place mentioned above and now it's just a case of waiting for a call to say if they can supply them or not. In the meantime I'll begin cleaning up a 40-odd pound beast of a circular saw (yes, another one!)


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## dickm

Ah, those seals take me back! Repairing/rebuilding all sorts of machinery, from garden stuff to classic Volvos. But much dirtier than woodwork!


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## Mark A

Hi chaps,

How can I clean the accumulated grime off the motor? The stator windings can hardly be seen beneath the layer of crud.

Bearing in mind this motor is almost 70 years old I don't want to use solvents in case it damages the varnish. 

Thanks,
Mark

(I've changed the title of the thread since the gear issue is solved (hammer) )


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## dickm

First off, gentle physical removal with soft brush/plastic or wood spatulas? Then maybe some carefully applied washing up liquid, worked into the crud with the soft brush and then washed off with hottish water? Though it's quite possible that the insulation is shellac, which might not even take kindly to getting wet, and would certainly soften with most organic solvents (I think)

(you had me puzzled with the change of title for the thread - before doing that sort of thing, think of us slightly senile septuagenarians  )


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## Mark A

Sorry 'bout that, Dick!

What then after brushing, washing and rinsing? Dry in oven and reapply varnish stuff? 

I've seen electric contact cleaners recomended online and found these on the Maplins site. Some state they're safe for use on plastics. What do you think?

Thanks,
Mark


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## CHJ

I would not use any solvent based cleaner, as Dick says could well be shellac on the windings, it's what we commonly used in the days when we rewound soldered comutator Black & Deckers and similar small motors.
They were usually placed in a cool oven for a few hours when re-coated.

Might be a good idea to have a look at the comutator segments while you are at the cleaning stage, burnt/scored or carbon glaze across the segment gaps.
We invariably re-cut the insulation a few thou below the segment level (old hacksaw blade with ground hooked end)
But the above may be a step too far if you have never refurbished an armature before.


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## Mark A

Hi Chas,

As far as I can remember, the commutator is in pretty good shape. Just dirty like the rest of the motor. 

Would I need to reapply shellac after cleaning and drying?

Thanks,
Mark


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## CHJ

Judging by the image you provided I would leave it alone as far as re-coating, it looks pretty sound as is. A good once over with a soft brush as dick mentioned (tooth brush for instance) should shift most of it. 

If you lightly polish off the commutator use fine (400-600 grit) garnet or glass paper, do not use emery. Carbon on the segments is OK, (lubricant) but you may also have burnt on oil film as well by the looks of it.


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## Mark A

Hi chaps, 

I've brushed off the crud coating the stator; though it's still greasy, which means it'll be a magnet for sawdust. I'm considering trying baby wipes - I haven't found anything which resists them and if they're gentle enough for babies then surely it won't affect the windings since they're alcohol-free? 

The oil seal suppliers I mention above are going to contact me tomorrow with a price. 

In the meantime I've started electrolytically de-rusting the Myford planer. One bed is done and is now soaking in a tub of caustic soda solution to remove the paint. 

Thanks, 
Mark


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## dickm

Difference between baby's backsides and shellac is that the former don't dissolve in anything! 
You are PROBABLY OK with wipes, but I'd recommend you try them out on a bit where the varnish is reasonably accessible and check whether, after wiping a few times, the surface feels more (which is bad) or less (which would be OK) soft and greasy. If the shellac is dissolving in whatever solvent is in the wipes (it might be citrus oil - see what they smell like) then you should be able to feel this.


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## Mark A

Hi Dick,

Just been researching baby wipe ingredients and I think you're right, the alcohol-free versions do contain citrus oil. 

If the original shellac is removed can I give the stator a fresh coating of shellac or varnish? A quick search dug up this

Thanks,
Mark

P.S. I find baby wipes absoultely indispensable - they remove oil, grease, dirt and [wet] paint yet cost less than a quid for 60 or 70 wipes. Much cheaper than "trade wipes" and just as good.


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## dickm

Can't see any reason why you shouldn't give another coat of shellac, but my preference would be to accept a bit of dirt and under- rather than over- clean, so you don't risk disturbing anything while the shellac is soft.


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## Mark A

Hi Dick,

Suppose you're right. Just seemed a shame to leave it when the rest of the saw's nice and shiny. I don't like doing half a job. 

I'm waiting for the replacement oil seals and then I can start putting it back together.

Thanks,
Mark


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## dickm

Mark A":2yk4omdn said:


> Hi Dick,
> 
> Suppose you're right. Just seemed a shame to leave it when the rest of the saw's nice and shiny. I don't like doing half a job.


Me neither; on the other hand, over-cleaning might end up with it being one and a half jobs


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## Mark A

The industrial supplies firm I linked to above could source a pair of seals, but their contact wanted £40 each for them because of the odd sizes! :shock: 

They suggested I try another company, Clydach Bearing Supplies who stocked the correct oil seals at a very reasonable price. Success! 

I'll set about putting the saw back together this evening. 

Thanks for all the advice, chaps! 

Mark


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## Mark A

Hi chaps,

The "Ripsnorter" is finished!







Admittedly it doesn't appear very different to when I began, but internally it's now in good working order. I didn't bother painting the base and lower guard because I intend to use the saw and it would just wear off.

Now the Ripsnorter's out of the way I can focus on some of my other tools which are at various states of restoration: a Myford planer, a Wolf RS10 circular saw and an 8" B&D circular saw.


Thanks for all the advice, it's very much appreciated!


Cheers,
Mark


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