Bandsaw Upgrade Advice Needed!

[SteveJ]

Hi everyone,

I finally got hold of a bandsaw, a Kity 612... not the biggest but it'll suit my needs for the time being and has a good hefty motor on it.

I've been looking at possible upgrade options to get the most from it, Axeminster do the upgraded guides, not sure about fitting though I've heard it can be problematic - has anyone had a bash with them?

Now while I most decidedly not their greatest fan, and certainly not in a minority in that view, Rutlands do some bearings which take the place of Cool Blocks or rubbing blocks which caught my eye - any opinions? I've emailed them to ask for dimensions which they oh so helpfully neglected to stick on the website :roll: .

http://www.rutlands.co.uk/machinery-&-a ... ler-guides

Cheers, Steve.

 

[RogerS]

Ah..Dakota...must be good then.

 

[studders]

I fitted the Axminster guide kit to my bandsaw, it was far from straightforward. I had to....

Cut off the round post fitting
Make up an adapter plate
Shim up the table to get the bottom guide to fit
Shim out the table to clear the adjuster screw
and a few other bits of fiddling to get things lined up.

I suppose it was worth it in the end as adjustment is now quick and easy. Probably wouldn't bother on another bandsaw though if the existing guides were half way decent.

 

[SteveJ]

Yeah I know roger... seems a worthwhile product though, which I can't find anywhere else.

That sounds like a right royal pain in the ar*e studders, not sure I could handle such extensive modding without fear of ruining my saw :shock:

The upper guide as it is seems fairly sturdy, runs on a hex bar 15mm in diameter and has a large back bearing. The lateral support comes from rubbing blocks which are a long way past it, hence my enquiry - same story for the lower rubbing blocks too.

I'll await Rutland's reply (will not be holding my breath though) about the dimensions and go from there methinks.

 

[devonwoody]

I've got a Record bandsaw rsb12,, and originally I used to be very meticulous about setting the guides with feeler gauge etc. to get the correct clearance.

These days, I just gently push the bearings against the blade I am using and never seem to have any sawing problems.

I think it is down to having the top wheel tension really tight and the blade is quite content to stay on track. (mainly depths upto around 100mm are being resawn, might be different for greater depths perhaps)

Its the blades that count.

So perhaps you don't need to bother with bearings. ( I have heard that some machines do not have below bearings. )

 

[RogerS]

...
I think it is down to having the top wheel tension really tight

That's a miracle of engineering to have separate tension on the top wheel from that on the bottom wheel!!!!

Its the blades that count.

True - they are one key factor

So perhaps you don't need to bother with bearings. ( I have heard that some machines do not have below bearings. )

That's nonsense. The bearings are there to stop the blade (and your cut) from wandering all over the place. No bearings on the bottom? Then I'll show you someone struggling to cut straight unless all they are cutting are 1/2" balsa wood.

Steve Maskery and I spent a day experimenting, tweaking, 'what-if'ing' on a large Basato 5 bandsaw. I agree that bottom bearings are not as important as the top ones but still needed.

 

[devonwoody]

Roger, I think some Startrite machines have no blade guides below the table.

If the blade is sharp and heavy (.032 thick) I can resaw 100mm these days without my guides. (apart from the back bearing perhaps)

 

[tekno.mage]

Hi SteveJ,

I inherited a Kity 613 bandsaw and my partner replaced the worn out guide blocks on it with some made from small pieces of walnut I had left over from a turning project. The walnut blocks have been on there nearly a year and are working just fine. We recently had to replace the back bearing as it seized (it wasn't in very good nick when we got the saw) - but were able to source another bearing from our local Bearing Man shop at only £2.75p.

tekno.mage

 

[RobertMP]

I fitted the Axminster guide kit to my bandsaw, it was far from straightforward. I had to....

Guess it depends on the make of saw you have. I bought the Axminster guides too recently. Easy straight replacement that took 15 minutes.

The one thing puzzles me about bandsaw guides is why the bearing that does all the work at the back of the blade runs sideways mounted with the back edge of the blade scuffing away at the side of the bearing. The ones that have an easy time running on the blade sides act as normal rollers - why not the back one that has to push against cutting pressure ?

 

[SteveJ]

Quick update... rutlands got back to me in 13 hours :shock: the bearings will fit....

In the meantime I nipped down to my local woodworking shop (Kraft Kabin in Stoke - highly recommended!) and had a natter during my lunch break (bagged an M42 1/2" 4tpi skip tooth blade too 8) ) . The chap there also recommended I stick with wooden rubbing blocks, beech if possible. The saws currently equipped with what I think are cool blocks, they are royally buggered though so will try the wooden option up top.

Down below I can confirm that some saws don't have bearings... mine is equipped with rubbing blocks alone. Will whack in some wooden jobbies since I'm doing the upper guide and go from there. From the sounds of things I should probably figure out some bearing arrangement below the table though... tricky since theres no room under there, will have a ponder and bear the rutlands jobbies in mind.

RobetMP - that thought occured to me too while window shopping the last couple of days... it is an odd arrangement, must be a reason for it.

Cheers everyone,
Steve.

 

[Jake]

The one thing puzzles me about bandsaw guides is why the bearing that does all the work at the back of the blade runs sideways mounted with the back edge of the blade scuffing away at the side of the bearing. The ones that have an easy time running on the blade sides act as normal rollers - why not the back one that has to push against cutting pressure ?

It takes the most pressure, so that stops it being a single tiny point of contact.

It neatly illustrates the main flaw with bearing guides.

 

[devonwoody]

If the back bearing faced the other direction it would eventually have a groove (indentation) worn by blade pressure.

That would then cause Guide problems?

 

[Woody Alan]

The chap there also recommended I stick with wooden rubbing blocks, beech if possible

There is no reason not to use beech but Lignum vitae or similar naturally oily wood would be better. If you are to use beech I would try soaking them in a light machine oil or WD40 perhaps.
This has been discussed before on the forum do a search for cool block and click the search for all terms button.
The real thing is very prevalent in the US
http://www.leevalley.com/wood/page.aspx ... 36&p=30072
being just one example.

Alan

 

[CHJ]

If the back bearing faced the other direction it would eventually have a groove (indentation) worn by blade pressure.
That would then cause Guide problems?

John if you see more than a polished line on an outer bearing race after a couple of years use then it most likely would have failed through the bearings wearing the track away. The hardness of a bearing race is 80 - 90% on the way to a file that you would use to sharpen the blade.

Many machines, especially metal cutting bandsaws, actually have a special order bearing supplied with a central outer race groove specifically to aid guidance so that the blade stays at a set position in relation to the clamping or measuring reference points.

 

[woodbloke]

I think are cool blocks, they are royally buggered though so will try the wooden option up top.

Down below I can confirm that some saws don't have bearings... mine is equipped with rubbing blocks alone. Will whack in some wooden jobbies since I'm doing the upper guide and go from there

Cheers everyone,
Steve.

I've got an Inca Euro 240 with so called 'cool blocks' above and below the blade. I replaced the original metal ones with two sets made from some lignum, which is self-lubricating. They're pushed up tight against the blade until they make contact and then left, the passage of the blade past the block faces soon wears just enough clearance. Cool blocks work well IMO if wooden ones are fitted rather than the original metal ones - Rob

 

[devonwoody]

CHJ.
The back bearing on my upper set has a 1 to 2mm surface wear off and because the back bearing spins it wears equally?

 

[CHJ]

CHJ.
The back bearing on my upper set has a 1 to 2mm surface wear off and because the back bearing spins it wears equally?

John I doubt that the back disc on your machine is hardened to the same level as a standard bearing outer race, if it is worn to that extent it indicates to me that the principle of a blade passing over the face of a rotating disc is resulting in a certain amount of 'skidding' as the disc passes first one way and then the other behind the blade and this is causing the thrust disc wear. I have yet to see any significant indication of the same on a standard bearing arranged to run co-planar with the blade despite the minimal contact area.