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RB211
02-06-2018, 04:37 PM
This thing was a lemon since day one. Same one that I replaced the worm gear on and lapped it in with valve grinding compound to the terror of this forum. (Apparently I got all the grit out, still works).
Well, the bottom wheel would always throw the blade off if there was too much tension on the band, but if the tension wasnít tight, the blade would kick off too! Canít adjust the tracking of the bottom wheel, so I cheated and machined the wheel to have a negative rake that keeps the band on the wheel. Hereís my mini-lathe machining the wheel, itís one of those 8xXX lathes.
https://uploads.tapatalk-cdn.com/20180206/2f59f79fdb3be98f790d593cc98c0467.jpg
https://uploads.tapatalk-cdn.com/20180206/7fc32b69a882e0bcdb75d6d1a366677d.jpg

It now works!


Sent from my iPhone using Tapatalk Pro

mikem
02-06-2018, 05:51 PM
I assume that you made the wheel slope toward the rim, so that if the blade slips, it slides toward the rim rather than off the open end? My bandsaw throws the blade also, and it isn't the cheapest of models. Maybe I will have to do this to mine.......

BCRider
02-06-2018, 06:08 PM
If that's the "after" picture then you sure didn't take a whole lot of material off. Or did you mostly just flatten it?

I know that on a belt sander I've got I had a bugger of a time keeping the belts stable until I removed the crowning from one of the drums. So perhaps simply removing the crowning is enough for this case too?

RB211
02-06-2018, 06:30 PM
I added 2 degrees towards the rim, so yes, the blade does not slip off anymore. Doesn't take much.

boslab
02-06-2018, 06:58 PM
Well fixed, nice when you get somthing to finally behave, bandsaws are always cranky things
Mark

JoeLee
02-06-2018, 08:11 PM
Machining the wheel sounds like it is or was your only choice in resolving your issue. It makes sense.
From looking at the drive wheel chucked up in your lathe I'm guessing your band saw is one of the million or so copies of someones saw like my Wilton, they are all pretty much the same.
I can't remember if the drive wheel is adjustable on mine or not, I believe it's fixed. The top or tension wheel is adjustable to keep the blade from running off the wheel and I'm guessing that more or less takes care of the drive wheel too. I've never had a blade run off either wheel.

JL..............

RB211
02-06-2018, 10:34 PM
The issue is that the drive wheel flexes towards the top wheel under tension and the blade wants to slide off due to the resulting angle. Yes, I suppose I could make a new drive shaft, fit angular contact bearings, pretension them, and re-bore the casting to accept the new setup.
I could also take a sledgehammer to it, and give it the burial it deserves.
This quick fix was a stop gap measure to take it off death row. I am upgrading the shop, and everything that is deemed to be junky is going bye bye. The air compressor took a nice ride to the dump today.
The little lathe is getting sold, itís going to get replaced by one of the many 12x36 units out there.

Sent from my iPhone using Tapatalk Pro

Machining the wheel sounds like it is or was your only choice in resolving your issue. It makes sense.
From looking at the drive wheel chucked up in your lathe I'm guessing your band saw is one of the million or so copies of someones saw like my Wilton, they are all pretty much the same.
I can't remember if the drive wheel is adjustable on mine or not, I believe it's fixed. The top or tension wheel is adjustable to keep the blade from running off the wheel and I'm guessing that more or less takes care of the drive wheel too. I've never had a blade run off either wheel.

JL..............

wierdscience
02-06-2018, 10:55 PM
If it works it's a good fix,well done.

On my Grizzly 5x6 miter head I had the same problem,but mostly because I was cutting soft material,with a heavy feedrate.The band would start slipping on the drive wheel and track off.I fixed that by reducing the contact area.Took the wheel off and machined several grooves in the surface with a parting tool.

Then the saw developed a squeal in the gearbox.Opened it up and the oil was full of Bronze.The snap rings meant to retain the worm shaft were nowhere to be found,thanks Won Hung lo,which allowed the worm to screw itself out part way and wear the worm wheel to hell.Replaced that and so far,so good.But I have a better remedy in mind.
https://www.ebay.com/itm/Lexar-Industrial-MRV050-Worm-Gear-40-1-56C-Speed-Reducer/361206558529?epid=7007841896&hash=item541996af41:g:uPUAAOSw~QRZ9f6M

darryl
02-07-2018, 01:41 AM
I jammed the blade on our bandsaw at work today cutting some stainless rod. At first it seemed like the blade just stopped while the wheels kept going. But it was off the wheels, so I attempted to place it back on them. Took the tension off with the top adjuster (so I thought) and tried to put the blade back on. With the top wheel all the way down in its adjustment range, I couldn't fit the blade back on. I ended up getting the blade on as much as possible, then pressing the blade tightly against the upper wheel and turning the saw on. The blade tensioned and stayed on the wheels, and I still have all my digits. Perhaps the blade is a bit short- there's no further adjustment that could have been made to allow the blade to be mounted before tensioning. In any event I didn't need to add any tensioning via the adjustment, and the blade stayed on for the rest of the cutting.

These little saws (4x6) definitely have some issues, but they can be addressed and the saw will be decent enough for its capacity. Mine at home has been working for about 20 years now with no major problems. I hope it continues to work ok-

bob ward
02-07-2018, 05:04 AM
This is what I refer to if my 6 x 4 bandsaw is playing up, it came from this yahoo group https://groups.yahoo.com/neo/groups/4x6bandsaw/attachments/1768615428

Basic blade adjustment and tracking - rev-1.pdf

strokersix
02-07-2018, 09:30 AM
I bought a Grizzly version about 30 years ago. Good blades, better stand and a couple minor tweaks is all I've done to it since. We all know these saws are crap but I have to say that work accomplished versus money spent, this saw is at the top in terms of value in my shop! The original motor is long gone...

BCRider
02-07-2018, 01:49 PM
More than many other asian machines these cheaper saws suffer from being badly tossed together. No doubt about that.

Best bet is to assume that nothing at all on them is set up correctly. There's lots of good material out there on setting up a bandsaw. And it starts with ensuring that the wheels are actually in plane with each other and works up from there. Wood or metal it matters not.

My own saw checked out OK for basics but one of the guide blocks was WAY off kilter and I had to widen a groove in the block to allow it to sit over under the other block and hold the right angle so the blade would cut straight and true So trust nothing on them if they give you any grief. RB211's issue is just one thing that can be wrong. And in fact if the wheel was "flexing" then I wonder about how the gearbox is for sitting against the main frame. There my be something in there that is letting it flex instead of seating solidly against the frame. I know that my own drive wheel shows no visible signs of flexing while tensioning the blade.

3 Phase Lightbulb
02-07-2018, 02:14 PM
I remember getting my HF 4x6" horz bandsaw (I believe it was a 4x6"). It was one of the 1st "real" metal cutting band saws I had. I soon realized how incredibly useful it was and when it was time for an "upgrade" I decided to get a much bigger one with coolant, and adjustable hydraulic lowering with automatic shut-off, etc. As one of the first tests I almost took the blade off my old 4x6" and cut the old 4x6" frame in half with the new saw but decided to give it away to someone IIRC.

Anyway, if you're going to upgrade your tools, I highly suggest getting a larger horz saw with coolant + adjustable hydraulic lowering with automatic shut-off, etc.. They are amazing work horses and sure to last a lifetime in a home shop. I put mine on the same "useful" list as the HF shop crane.

BCRider
02-07-2018, 04:33 PM
I keep thinking about "upgrading" my own bandsaw. But I use the vertical mode just as often as I use the horizontal mode. And that makes me keep the cheap little 4x6. I don't have the room for separate saws.

If they had a slightly larger and better quality saw that still had the vertical mode I'd likely "upgrade".

3 Phase Lightbulb
02-07-2018, 06:51 PM
Having both a dedicated vertical and horizontal band saw make cutting different kinds of stock down trivial. The vertical is great for cutting plate with both straight edges and contours or anything you want really. They do take up a little bit of space but I found they actually fit best in areas of my shop where other tools wouldn't fit as nice so they kind of created space for me.

http://www.bbssystem.com/pictures/saws1.jpg

http://www.bbssystem.com/pictures/saws2.jpg

RB211
02-07-2018, 09:08 PM
Having both a dedicated vertical and horizontal band saw make cutting different kinds of stock down trivial. The vertical is great for cutting plate with both straight edges and contours or anything you want really. They do take up a little bit of space but I found they actually fit best in areas of my shop where other tools wouldn't fit as nice so they kind of created space for me.

http://www.bbssystem.com/pictures/saws1.jpg

http://www.bbssystem.com/pictures/saws2.jpg

Nice shop, nice boat, etc... So what exactly did you do that set you for life?

3 Phase Lightbulb
02-07-2018, 09:23 PM
Nice shop, nice boat, etc... So what exactly did you do that set you for life?

Find something you absolutely love to do, Do it really, really well. Do it better than everyone else can. It also helps if what you do is also in high demand, etc. The rest is easy.

RB211
02-07-2018, 09:30 PM
Find something you absolutely love to do, Do it really, really well. Do it better than everyone else can. It also helps if what you do is also in high demand, etc. The rest is easy.

That’s exactly what I am doing, but I will never see more than 400k a year from it. So what’s your claim to fame?

3 Phase Lightbulb
02-07-2018, 09:36 PM
That’s exactly what I am doing, but I will never see more than 400k a year from it. So what’s your claim to fame?

That's not a bad salary. I'm a software & hardware engineer.

RB211
02-07-2018, 09:43 PM
That's not a bad salary. I'm a software & hardware engineer.

This is like pulling teeth... In the live steam hobby, at the club near my house, one of the members is the kid who gets royalties from the magnetic strip on the back of your credit card. One of the clients at the flight school I used to work for was/is a software engineer/programmer, that developed something that gives him royalties to this day. I understand wanting to keep it secret, but let me take a wild guess...
You developed a compiler that other engineers love to use? PIC C compiler?

mikem
02-07-2018, 09:52 PM
I think that the reason that we use screen names is so we don't have to tell everyone exactly what we do!

tomato coupe
02-07-2018, 09:57 PM
Thatís exactly what I am doing, but I will never see more than 400k a year from it. So whatís your claim to fame?

If you're pulling down $400k per year, why are you fussing with a POS saw? Donate that one to a worthy cause and buy something good.

3 Phase Lightbulb
02-07-2018, 09:58 PM
This is like pulling teeth... In the live steam hobby, at the club near my house, one of the members is the kid who gets royalties from the magnetic strip on the back of your credit card. One of the clients at the flight school I used to work for was/is a software engineer/programmer, that developed something that gives him royalties to this day. I understand wanting to keep it secret, but let me take a wild guess...
You developed a compiler that other engineers love to use? PIC C compiler?

That was awhile ago. I've built C compilers that target 32 different uP/CPUs. Today I mostly do R&D that target new enterprise grade technology that is 3-5 years out.

RB211
02-07-2018, 10:04 PM
If you're pulling down $400k per year, why are you fussing with a POS saw? Donate that one to a worthy cause and buy something good.

I said I will, not that I currently am. I am still a first officer. Grossed 130k last year. Will go to low to mid 200ís when I upgrade to Captain. I am open about this because itís a union job and the pay details of my contract are open to the world to see. Itís public knowledge.
If I was single, my shop would look like 3phases!
When it comes down to it, I promise to give the bandsaw away for free instead of going ďOffice SpaceĒ on it. No, sorry, I am going Office Space on it. It owes me that!

RB211
02-07-2018, 10:08 PM
That was awhile ago. I've built C compilers that target 32 different uP/CPUs. Today I mostly do R&D that target new enterprise grade technology that is 3-5 years out.

You’ve really mellowed out ;) Still do sky diving?

3 Phase Lightbulb
02-07-2018, 10:11 PM
You’ve really mellowed out ;) Still do sky diving?

The wife and I used to skydive all the time. We haven't skydived in over 10 years. When my son is of legal age I'll get back into it and bring him to the drop zone and jump with him. The wife wants to jump again too but just too busy with young kids.

lugnut
02-07-2018, 11:36 PM
The HF 4X6 saw is not a bad thing. All you have to do is uncrate it, throw all the bad stuff away, and tweak the good parts and if you not a complete dummy, you can come with a pretty good saw, great for the average Home Shop Machinist. There has been a ton of good articles written and posted that tell what needs to be done. Take a $200 saw, add a $25 blade and a few hours of time and your all set. ;) I have had two of them and use the one I have now almost every day. Wouldn't part with it.

Joel
02-07-2018, 11:49 PM
If you're pulling down $400k per year, why are you fussing with a POS saw?
It is amazing how incredibly inefficient a majority of people are with money.

3 Phase Lightbulb
02-08-2018, 12:21 AM
Some habits are hard to break. I still get a sinking feeling sometimes when I have to buy a 20oz Gatorade or a Power-Aid drink for $4 or more at a venue somewhere. I know damn well it only costs me ~$4 or less for an 8-pack from PeaPod. Something about paying 500-1000% more than you should just gives me the willies.

RB211
02-08-2018, 03:14 AM
It is amazing how incredibly inefficient a majority of people are with money.

400k is the most I could realistically make at my company. I grossed 130k last year, but I only keep 250$ a paycheck for my hobbies. The majority of my excess income goes to savings and retirement.
Amazing how judgmental some people are...

reggie_obe
02-08-2018, 07:18 AM
If you're pulling down $400k per year, why are you fussing with a POS saw? Donate that one to a worthy cause and buy something good.

If you're pulling down 130k and fly for a freight company, why haven't you bought a decent used saw in a machinery rich area and brought it home? Surely they allow you to bring more than an overnight bag on the plane?

Brett Hurt
02-08-2018, 08:05 AM
I have had my hf 4x6 saw over 30 years, it sill runs cuts stright changed the guide bearings too skf been runing them for 5 years that inproved it a lot.

JoeLee
02-08-2018, 08:35 AM
I had to fine tune mine also. The first thing I had to do was square up both vise faces. Then I went on to fine tuning the blade guides. I think I replaced the bearings once many years ago. The originals didn't last long, maybe a couple years but the replacements are still going. Finding a good blade is also important.

JL..............

3 Phase Lightbulb
02-08-2018, 08:52 AM
One feature of the vertical band saw that I haven't used yet is the built in blade cutter, blade welder, and blade grinder. This would be useful if I want to cut out an inside shape with the blade going through a piece of material. I would remove the blade from the saw, cut it with the built in blade cutter, put the blade though my material, weld the blade back together using the built in blade welder while it's still through my material, grind it smooth with the built in grinder, then re-attach the blade back on the machine while it's still going through the material. After I'm done with the inside cuts, I then remove the blade, cut it again, remove material, re-weld/grind it and install back on the machine.

JoeLee
02-08-2018, 10:02 AM
You must have a pretty big band saw if it has a welder bolted to the side. Nothing like that on these 4 x 6 cut off saws.

JL..............

3 Phase Lightbulb
02-08-2018, 10:07 AM
You must have a pretty big band saw if it has a welder bolted to the side. Nothing like that on these 4 x 6 cut off saws.

JL..............

You can see the blade cutter, welder, grinder on the side panel

EDIT: I'll take a nice close up picture tonight and post it.

http://www.bbssystem.com/pictures/saws2.jpg

RB211
02-08-2018, 11:49 AM
If you're pulling down 130k and fly for a freight company, why haven't you bought a decent used saw in a machinery rich area and brought it home? Surely they allow you to bring more than an overnight bag on the plane?

Thereís specific rules against that, besides, we are doing contract flying for DHL and everyone else. I am in Hong Kong and China frequently, the 747 has no issues carrying a large mill or lathe, but it isnít that easy.
I only get to keep 250$ a paycheck for my toys. Being that I just spent 5,000$, will need to make a deal with the wife that any ďday off flyingĒ I do, goes directly to paying off the new purchase.
Like I said, if I was single, no kids, and financially irresponsible, Iíd have one hell of a shop. The wife doesnít work, sheís taking care of my daughter that is special needs.

3 Phase Lightbulb
02-08-2018, 12:19 PM
You missed Top Gun, eh? I always wondered who was flying those planes full of rubber dog sh*t out of Hong Kong. :)


https://www.youtube.com/watch?v=jdXkUyC3VNQ

RB211
02-08-2018, 12:59 PM
You missed Top Gun, eh? I always wondered who was flying those planes full of rubber dog sh*t out of Hong Kong. :)


https://www.youtube.com/watch?v=jdXkUyC3VNQ
Yep, that’s me!

tomato coupe
02-08-2018, 01:18 PM
Yep, thatís me!

Darn. I was sure you were that guy that got stuck on an island with nothing but a volleyball.

RB211
02-08-2018, 01:20 PM
Darn. I was sure you were that guy that got stuck on an island with nothing but a volleyball.

Ditching in the Atlantic Ocean... Good luck!!!!


Sent from my iPhone using Tapatalk Pro

3 Phase Lightbulb
02-08-2018, 03:20 PM
Picture of blade cutter/welder/annealing/grinder:

http://www.bbssystem.com/pictures/bs_welder.jpg

Tundra Twin Track
02-08-2018, 03:59 PM
I have one those 4x6 don't use any more cut a lot of material with it,spent a lot of time sitting on it behind vise in vertical position.

RB211
02-08-2018, 04:12 PM
Picture of blade cutter/welder/annealing/grinder:

http://www.bbssystem.com/pictures/bs_welder.jpg

Your shop is way too clean, what do you like to make?

3 Phase Lightbulb
02-08-2018, 04:27 PM
Your shop is way too clean, what do you like to make?

I haven't made anything yet as I'm still setting it up. I need to finish bringing power to a few more machines and organize a bunch of massive clutter in certain areas and then I'll finally start working on the first project in my new shop. Haven't decided exactly what it will be, but it will be something motorized for my son.

BCRider
02-08-2018, 05:11 PM
I haven't made anything yet as I'm still setting it up. I need to finish bringing power to a few more machines and organize a bunch of massive clutter in certain areas and then I'll finally start working on the first project in my new shop. Haven't decided exactly what it will be, but it will be something motorized for my son.

I was going to say that RB hasn't seem some of the other pictures of that clutter.... but you beat me to it! :D

RB211
02-08-2018, 05:42 PM
I haven't made anything yet as I'm still setting it up. I need to finish bringing power to a few more machines and organize a bunch of massive clutter in certain areas and then I'll finally start working on the first project in my new shop. Haven't decided exactly what it will be, but it will be something motorized for my son.
Hmm, a tube bender and tig welder would be nice for that too!

3 Phase Lightbulb
02-08-2018, 06:10 PM
Hmm, a tube bender and tig welder would be nice for that too!

I have a nice TIG welder but my tube bender is the HF tube bender with the bottle jack and the curved dies. I actually was able to make many bends with it but it;s only good for SCH40 pipe and will kink any type of thin wall tubing.