Thread: Wadkin DN Bandsaw Restore - Early 1900s

Originally Posted by Charlie_6ft

...Do machines just take general purpose automotive grease?

Jack uses an SKF grease - I don't recall it's exact name, but I think it's available from SFK bearing agents.

The Maintenance Instructions for my Wadkin PK specify:
Grease: Wadkin Grade L.6
Alternative grease: Shell NERITA GREASE 3; GARGOYLE GREASE BRB 3; REGAL STARFAK No.2 GREASE

These are all obsolete names

I enquired of a local Mobil service station that still supplies products other that petrol and pies

Here's what I got back from them:
Hi, thank you for your query on grease and oil for your Machine.
The Grease No. 2 equivalent is Mobil Grease XHP 222...

As your bandsaw bearings will be turning at a much lower speed than the PK spindle, the Mobil grease should be more than good enough. I bought it in 400gm tubes at about $NZ11 each (I don't know if it also comes in tins).

Edit: I hadn't seen Gaza's post when I wrote my reply. Jack's instagram post will most likely have better information (I don't do Instagram - I'll have to figure out how to have a peek).

Cheers, Vann..

Vann....Jack doesn’t talk about grease but does a damn good explanation of the bearings and what to look out for when reordering...it’s not just the numbers on them. But different grades within those numbers. I was impressed. But then I am pretty clueless when it comes to bearings

Thanks Gaza\Vann,

I have taken a look at Jack's video; Jack Forsberg on Instagram: “There’s always a little bit more to bearings than the numbers printed on the outside. I describe some Call me bearings in English machines…” - very informative. That grease is sub $10 here in Oz I think I'll stick to these bearings for now since they don't look to be worn and seem to be superior to anything else.

For record keeping and to help someone else as insane in taking on a rusty DN restoration, below are the bearings I have in my machine for the lower shaft:

20200504_194041_resized.jpg 20200504_194054_resized.jpg

This bearing is made in Germany by FAG:

Outer race: RM12 | T | U.B
Inner race: RM12 | A | U.B

I've got myself in a pickle. I've got one bearing off. BUT on the other side it's a no go. There are two issues:

1) I can't get the key off the shaft. I've tried a few things; Heat, taping it with a cold chisel from one end and putting vice -grips and whacking it with a drift downwards.
2) I can't actually get it to go back into it's housing. After pushing it through to get the other bearing off I can't get it to go through the same hole it came from. I've made sure the outer race is square and taped the opposite side with a hammer (gently) but it just doesn't seem to want to slide back in.

20200504_150431_resized.jpg

When I look up through the bottom of the saw I can see the bearing itself (on the left) and a ring (on the right) which spins also (not sure if this has some sort of bearing too). The ring provides a gap for grease to sit in for the bearing as far as I can tell and protects it from any dust coming in contact with the grease.

20200504_145605_resized.jpg

There is no way I'll be dislodging the housing that runs through the centre of the frame. I have taken some paint off around where it makes contact to the frame and squirted releasing oil to no avail. I've hit it pretty hard with a hammer (with a block of wood for cushioning) and it's going nowhere. Thats not such a big deal however as I can't see that I need to remove it. I really just need to remove the shaft and bearings. In the picture below I've successfully removed no.1 bearing. no. 2 is what is giving me the trouble per above.

Screen Shot 2020-05-04 at 9.06.59 pm.jpg 20200504_195138_resized.jpg 20200504_195213_resized.jpg

To get keys out that are stubborn I use an old wood chisel and place the tapered side down then hit into the key and lever the key up out of the slot, You can clean it up after its out

Thanks Wallace - a combo of Reducteur H-72 Super Rust Releasing Agent, Heat & vice-grips hit with a brass drift did the tick. Not just got to get the bearing off.

On another topic. I did some comparisons regarding RPM as I look for replacement motors and pulleys. Below is a comparison given what came with each of the bandsaws. The Wadkin runs at the highest speed at the drive wheel.

Screen Shot 2020-05-08 at 7.08.31 am.jpg

The pulley on the motor of the Wadkin isn't original and should be a 3V to match the pulley on the drive wheel so I can run 3 belts (probably over kill but would complete the look). I have two options as below and used Pulley size and RPM to calculate RPM speeds, this doesn't factor in belt lengths etc.

1) As I can only find a 2V (A Type) I could try and source a single V and weld them together to make a 3V. I only have 50mm of shaft length on the 240v single phase motor (refer below pic) but think it'll be OK. Conon have this 2V - Double-groove Pulley 120mm shaft size 28mm castiron A type belt motor compressor | eBay

2) I could reduce nominal diameter of the motor pulley, run the RPM at a lower speed and get a much smaller 3V pulley. RPM at the drive wheel which would drop down to about 334 RPM - this to me is super slow and lower then the current speed of the Crescent (refer to above pic). Conon have a 3V - Triple groove Pulley 70mm shaft size 28mm for electric motor Cast Iron Made | eBay BUT not a single V at this size so may need to source one elsewhere.

Screen Shot 2020-05-08 at 7.20.49 am.jpg

What sort of RPM should this saw run at? There seems to be no benchmark?

General bandsaw blades are designed to cut at a speed of around 900 m/min. They will cut very effectively at speeds below that so for a hobbyist dont obsess too much about it. I have a couple of older saws (early 1900's and 1930's) and the quality of the cast iron is not as good as more recent machines (post 1950's). I will be running these machines at about two thirds of the current commercial bandsaw cutting rates.

I think with band saws the critical thing I’d the blade speed. Ie 3000 feet per minute for timber or around 1000 meters per minute. The bigger the saw the slower the wheels will need to turn.
Gaza

Looking at the attached chart I think that maybe A and B are reversed because in most cases the speed on the drive wheel will be higher than the motor revs.

Thanks guys, I think I've found the solution to my problem:

SPZ Taper Lock V Pulley (1108) 63mm, 3 Groove Cast Iron SPZ63-3

Metric Taper Lock Bush - Cast Iron

Screen Shot 2020-05-08 at 12.02.24 pm.jpg

This system is actually really good as you can match pretty much any modern metric motor shaft to a very comprehensive pulley types\dimensions.

- - - Updated - - -

Thanks guys, I think I've found the solution to my problem:

SPZ Taper Lock V Pulley (1108) 63mm, 3 Groove Cast Iron SPZ63-3

Metric Taper Lock Bush - Cast Iron

Screen Shot 2020-05-08 at 12.02.24 pm.jpg

This system is actually really good as you can match pretty much any modern metric motor shaft to a very comprehensive pulley types\dimensions.

Found this online that may help with pulley selection.
Calculating Bandsaw Blade Speed

S.F.P.M. = Surface Feet Per Minute

Knowing the S.F.P.M. for your bandsaw can be very important to getting the most from a particular blade and when cutting various types of wood. The blade manufacturer often specifies an optimum S.F.P.M. for the blade but attaining that rate depends on your saw and the speeds (pulley diameters) available.

The formula to determine S.F.P.M. is:

Motor RPM multiplied by the Motor pulley diameter divided by the Driven pulley diameter times the Bandsaw wheel diameter times pi (3.1416) divided by 12 = S.F.P.M.
Motor RPM X Motor pulley diameter / Driven pulley diameter X Bandsaw wheel diameter x 3.1416 / 12 = S.F.P.M.

Calculating Bandsaw Blade Speed - NewWoodworker.com LLC
I poked the numbers in that you supplied and I would say that Bohdan is correct that the pulleys are back to front and even if you swap them you are still running at about 8000sfpm which is damn fast if 3000sfpm is the going speed.

So I've just run this through said calc:

S.F.P.M.
= 1435 (RPM) x 88mm (Motor pulley Pitch/Nominal Diameter) ÷ 233mm (drive wheel pulley Pitch/Nominal Diameter) x 720mm (Bandsaw wheel diameter) x 3.1416 / 12
= 1435 x 3.46457" ÷ 9.17323" x 28.3465 x 3.1416 / 12
= 4,020

This website has the calculator which was handy Calculate Band Saw Surface Feet per Minute (SFPM) | VintageMachinery.org

So with this being 1000sfpm over and in factoring a new motor (1400rpm) and new pulley (64mm pitch/nominal diameter) I'll have:

= 1400 x 2.51969" ÷ 9.17323" x 28.3465 x 3.1416 / 12
= 3,090

Many thanks Gaza and Co. I was about to put in an order on Monday for 3 x pulley's for three of the saws so will run through the same exercise for the others too.

I ran the calculations for each saw & their current state. I've worked within the range of available pulley's in orange to reduce S.F.P.M speeds. Whats interesting is none of these saws apart from the McPherson were running at speeds closer to 3000sfpm which doesn't surprise me as these saws would most likely have started their lives with flat belt pulley's (assumption) which were later replaced with what ever was available in a V-grove (assumption).

	RPM (new motor)	Motor Pulley Dia (in)	Motor Pulley Dia (in)	Saw Wheel	SFPM	Comments
Wadkin	1400	3.46457	9.17323	30.7087	4,249	Current state
80mm Pulley	1400	2.51969	9.17323	30.7087	3,090	Change down of 1,159
L.S. Barker	1400	2.44094	7.28346	32.6772	4,012	Current state
80mm Pulley	1400	2.51969	7.28346	32.6772	4,141	Smallest 4V available is SPZ 80mm
Crescent	1400	2.20472	5.35433	36.2205	5,464	Current state
56mm Pulley	1400	1.5748	5.35433	36.2205	3,903	Smallest 2V available is SPZ 56mm
McPherson	1400	3.54331	11.4173	31.8898	3,626	Original Flat belt pulleys

Here are the 2 pages that match the ones Henry put up from the 1929 catalogue.
Some data on pulleys etc
Tony