Band Saw question ?

[Blister]

Hi

My dad gave me his Draper band saw , he said when he tried to use it , it was rubbish :shock: :shock:

I had a look in the instruction book and there is nothing on setting up the 2 bearings and 4 guide blocks :roll:

I had a play with it and there is one thing I am not sure of

Above and below the table there is 1 bearing and 2 guide blocks

question is , does the back / rear edge of the blade run against the side or edge of the bearing ?

See the 2 photos

and

I think this is how they go ?

:?

 

[stevel]

It is correct in the photos, the blade runs on the face of the bearing. I hope it works better for you than it did for your dad.

Steve

 

[RogerS]

Same as on the big Basato and I can't see why they made the rear thrust bearing work this way. Maybe it's because they want the bearing to wear out prematurely so that they can sell you the whole set of top guides (because you can't buy the easily removable rear bearing by itself) for over £150 :evil: DAMHIKT

The sparks that come off it as the blade rubs down it is very offputting (and the bearing does ride freely and it is the recommended piece of papers' width behind the back of the blade)

A really, really duff design.

 

[greybeard]

The bearing acts as a backstop for the blade, otherwise it would try and disappear backwards and possibly fall off the wheels as you offer up anything that's a bit chunky.

IIRC the approved set-up is to have the blade running without touching (a gap thickness of **three sparrows kneecaps) between blade back and bearing front.
Then when you start to cut the blade moves fractionally backwards and the machine running noise changes tone as the blade touches and spins the bearing.

(** or approx 1 large chicken kneecap. If all else fails that's about 0.5mm - e.g. thick piece of paper)

Ah, I see Roger has beaten me to it, and he is as puzzled as i am about the design/use of the back bearing. Perhaps Scrit can throw some light?

 

[Shultzy]

Blister, I have the B&D band saw which has the same arrangement and as others have said its supposed to be how you have it in the pictures. I let the diagonal guide block fall under gravity and then lock it off, then move the horizontal guide block to just touch the blade. The band saw is a bit naff but I've had mine for over 30 years so its served me well.

 

[devonwoody]

Bandsaw costs are based on cutting capacity, but a satisfactory cut comes down to the quality of blade at the end of the day.
I havent needed to dump any bandsaws blades for nearly a year and they are still cutting true.

The bandsaw came from a member of this forum and the saw must be approaching 10 years old.

 

[MIGNAL]

I don't understand what the problem is with the arrangement of the back bearing guide. Works fine on my cheapo Perform, certainly no sparks! and the rear bearing has lasted some 4 years. I think something is amiss with that Busato and 150 notes is huge for a few bearings. Try a bearing specialist.

 

[RogerS]

I don't understand what the problem is with the arrangement of the back bearing guide. Works fine on my cheapo Perform, certainly no sparks! and the rear bearing has lasted some 4 years. I think something is amiss with that Busato and 150 notes is huge for a few bearings. Try a bearing specialist.

Well, Steve M's Basato is the same as mine and he gets sparks as well! Maybe it's something to do with the size of blade that we are able to use on the Basato (or rather the thickness of the blade) that makes the difference. A 1" blade is probably, I'd guess, twice the thickness of a smaller blade.

With this bearing design, seems to me that one is getting a dragging action rather than a rolling action and so the thicker the blade, the more drag, therefore the sparks fly.

I agree that you can get bearings at a better price elsewhere...just that the top thrust bearing isn't a ball race as I know it...just a bit of turned metal that spins in a phosphor bronze (or similar) sleeve. So...guess I need to go down my local fabricator and get another four or five made up....or design something better :wink:

 

[MIGNAL]

Sparks and sawdust, not the greatest combination is it?

 

[CHJ]

I have never understood why the design for the rear blade support would choose the face of a disc, whether it be rotating in a bush or the bearing option, it is inevitable that the system is constantly running in opposing directions and scrubbing the back of the blade, and on most machines you do not have the option of adjusting so the the blade is nearer the periphery to reduce this effect.

Having once been informed by a company rep. that their machine was superior because it used bearings as opposed to a steel disc, I did ask where they got the specialist bearing from designed for unbalanced side thrust :lol: might know it was a waste of breath.

 

[dickm]

I seem to remember this topic came up some while back, and Scrit was able to give a convincing explanation of why the back bearing is usually set in what looks like a silly way. (I'm pretty sure there is one saw I have seen where the bearing is the "right" way, but only one).
And, of course, if you have an old Startrite like mine, there is no bearing behind the blade, just a hardened steel rod. It sparks occasionally, but usually only when it's pushed too hard.

 

[Alf]

Dick, I think this is probably the thread you had in mind? Not surprising you remembered it really.

Cheers, Alf

 

[woodbloke]

Blister - I have the same arrangement on my Inca and it works well. The bearings can sieze tho' so a little squirt of WD40 (a good universal 'cure all') once in a while works wonders - Rob

 

[Blister]

Thanks everyone

I will buy a decent blade and see what happens