Clarke CBS45MD 6x4 Metal Cutting Bandsaw Modifications

[Wallace]

Thank you, without taking them out they look like 26mm o/d x 8mm W x 10mm bore.

I know the slack is adjusted out with the grub screw, but it is there and I know about it, sorting it out will probably not make any differance to its use but it will remove one more doubt from my mind.

10mm bore will be a 6000 series, about a £1 each for a budget bearing but double check before ordering, one of those little differences between the machine manufacturers.

How much slack is there between the plates and guide block? As you add blade tension the guide block will tip slightly taking up the slack on the plates, the grub screw only adjusts the wheel tracking to bring it parallel with the driving wheel.

 

[zx9]

I've got a spare set which I pulled off a sealy bow they might be a better fit Then what you have if you want me to have a look.
I've got a number of spare parts for the 6x4 as I got two complete bows to build mine from.

That would be much appreciated if you could have a look sometime, I will measure the thickness of mine later afternoon.

 

[Richard.]

Mine is much older than Wallaces' no CE markings or cut out / interlock for blade or pully cover.

Yeah mine is very old without those items too. It was a box of scrap when I got it. I added everything I needed when putting it together. Lots of spares sitting here if people need parts.

 

[Richard.]

That would be much appreciated if you could have a look sometime, I will measure the thickness of mine later afternoon.

No prob. Dig them out Tomoz. And have a little compare.

 

[Wallace]

It is not the gap between them that is causing the play it is the thickness of the plates in relation to the thickness of the V, almost as though the V was milled too wide or the clamp strips are too thin.

As your saw is an SIP, does the guide block have square slots or a V?

Just to confuse matters I checked the guide block on my other saw........ No tracking adjustment! The bearings on this one look to be 10mm bore too.

 

[zx9]

As your saw is an SIP, does the guide block have square slots or a V?
Just to confuse matters I checked the guide block on my other saw........ No tracking adjustment! The bearings on this one look to be 10mm bore too.


View attachment 72140

They are square, a V would not have the problem as the V would take up the slack. (My fault for referring to it as a V)

 

[Wallace]

They are square, a V would not have the problem as the V would take up the slack. (My fault for referring to it as a V)

You never know with these clone machines, they might look similar but often have many small differences. I have an old upright bandsaw that came to me in bits with a broken table trunnion and managed to buy an identical replacement from Axminster for a completely different looking modern saw.

 

[zx9]

I lied it is a Sealey not a SIP, the plates are 4.35mm thick whilst the groves are a shade under 5mm (I have nothing to measure small internals other than a set of compasses and a vernier caliper). Perhaps I am being too fussy, Richard please don't go out of your way to measure any spares you may or may not have.
I did check the ID of the bearings they are 10mm.

 

[Richard.]

Hi zx9 sorry didn't get chance to dig out sooner. There is no where near 0.6 mm clearance with these. They are a snug fit. If you want them cover the post and you can have them. These have come off a very old saw and one thing I have noticed everything seems to be thicker, heavier, better built than the newer ones. Your welcome to have the fitting bolts too but they are imperial thread

 

[zx9]

View attachment 72255 Hi zx9 sorry didn't get chance to dig out sooner. There is no where near 0.6 mm clearance with these. They are a snug fit. If you want them cover the post and you can have them. These have come off a very old saw and one thing I have noticed everything seems to be thicker, heavier, better built than the newer ones. Your welcome to have the fitting bolts too but they are imperial thread

Yes please Richard, may as well have the bolts too I had assumed a lot of the fixings are imperial because of the US market many/ most of them are sold to.
I will PM you re. postage.
Thank you.

 

[zx9]

View attachment 72255 Hi zx9 sorry didn't get chance to dig out sooner. There is no where near 0.6 mm clearance with these. They are a snug fit. If you want them cover the post and you can have them. These have come off a very old saw and one thing I have noticed everything seems to be thicker, heavier, better built than the newer ones. Your welcome to have the fitting bolts too but they are imperial thread

To update I have now fitted the above adjuster to my Sealey, it has taken out a lot of free movement from the shaft, both fore/aft and left/right. There is still movement in the bronze bush but other than fitting a taper roller bearing I don't think there is much you can do about that. Did changing over the parts make any difference to the saws operation, in use I don't thinks so but setting up is slightly easier because the shaft and hence driven wheel are less free to pivot when you tension the blade.

 

[Wallace]

Knocked up an adjustable jig for holding bandsaw blades square to Tig weld them. Have been using the two brass plates and toolmakers clamps until now to prove the method works but setting the blade up is too fiddly, this will make it easier and won't put me off doing more than one blade at a time. Will be adding another clamping arrangement for annealing the joint and grinding back the weld.

 

[Richard.]

Nice!!!! I snapped mine the other day (got jammed in a thin wall box).
I often thought about tigging it. That little device looks the proper job.

 

[Shox Dr]

What is are you joining?
I've never had a long enough life out of the repaired blade to warrant doing it, for my MM jobbie

I have however had plenty of success with welding bigger industrial size blades

 

[Wallace]

Nice!!!! I snapped mine the other day (got jammed in a thin wall box).
I often thought about tigging it. That little device looks the proper job.

Thanks, I've been welding them on the brass plate to get a uniform thin weld on the back face that doesn't need much grinding, once annealed and ground back they seem to be working well, better than the silver solder and brazing I tried.

What is are you joining?
I've never had a long enough life out of the repaired blade to warrant doing it, for my MM jobbie

I have however had plenty of success with welding bigger industrial size blades

I have repaired Clarke blades to get the last out of them and made new ones from 100ft rolls of Starret 1/2" blade for this and a modified wood upright bandsaw. Will post photos of it in use when I get time to make a couple of blades.

 

[Wallace]

Spent some time working on the blade jig and trialling a few joints on an old blade, ended up using all 93 inches! The result is still a work in progress for the jig adding clamps to hold the blade for annealing and grinding the joint back but the joints are coming out nice and strong. I currently have a blade running on my upright Nutool 14" saw and will knock up three tomorrow for the 6x4 saw in different tpi's to give them a proper bashing.

Fabricated a larger plate to use on my linisher in the upright position and with a sheet of 1.5mm sheet steel clamped in position the blade ends can be squared up.

Once squared off and to length for the tooth pattern the ends are given a clean up and deburr with a stainless brush for Tig welding.

The jig top plate is adjusted to allow the set of the teeth to overhang the lower plate edge and the blade is clamped in position.

A large tack added to the blade centre around 25A with the Tig using 0.8mm Mig wire as filler to pull the joint tight. The heat dissipates into the brass and alloy plate within seconds, by the time I had placed the torch on the stand and checked the temperature with a laser thermometer it was cold. The outer edges were then welded making sure enough excess was left to leave smooth notch free edges.

Very carefully without flexing as the joint at this stage is extremely brittle, the blade is unclamped from the jig, slid along for annealing and clamped to avoid distorting while heated to a dull cherry red with a butane pencil torch.

Used this tube over the joint to shield the light while annealing to see the dull cherry red better.

Turned the blade over to take this photo showing how little grinding is required due to the brass plate being under the weld.

Gentle grinding back of the joint, managed to lose less than 0.002" over the joint, must try harder! Back face draw filed to give a smooth run over the blade guide roller bearings.

Test joint twisted through 90°.

Test joint bent well in excess of bandsaw tyre radius.

 

[Richard.]

Cracking stuff.

 

[Wallace]

Cracking stuff.

Thanks, let's hope they don't crack! The joints are well brittle before annealing and really go with a pop if flexed, short blades will need to be kept straight on the jig. Wondering if I can anneal electrically using the Tig or a car battery.

 

[Richard.]

Like a short arc method? Could you do that and keep control of the heat though. I would imagine you want to keep it very local to the welded joint. I think you've got the annealing perfect as your doing it. The band saw blades don't go any where near a radius that tight so it's more than fit for purpose. The jig is a nice touch.

 

[Wallace]

No, I tried the lowest current on my Tig and it heats up oo quickly. I was thinking more along the lines of how a proper blade welder does the annealing, clamped either side of the weld then current passed through the bare minimum blade section. Not sure the Tig would like being shorted but the pedal would make temperature control easy!