regarding the "slow down your machine the inexpensive way that no one is talking about" video

[wydfuqnopn]

Not trying to beat a dead horse here but many of you folks have seen and commented on this video from you tube  https://www.youtube.com/watch?v=9y2Aapk7X8E&t=3s . The author makes claims and shows proof of concept for changing the pulley on the servo motor to a 50mm smaller one and instead of a standard speed reducer, he proposes changing the hand pull on the actual head to a larger one. He is using a consew 205RB-5 machine and after he changes out the pulleys, it does show a significant change in slowing down the system in a similar way that the generally accept method achieves. I recently purchased this machine and saw the video and it has been on my mind ever since. I have changed out the hand pull for a 6" one and will be changing the servo one later tonight before adding the correct belt.

He makes the claim that no one is talking about this. He sort of infers that that is because all of the people he has spoken to that are in the business do not want to lose business if everyone starts doing this. Some of you have mentioned that the cost of the larger pulley for the head has gained because of the video and I myself have verified that the costs are certainly higher than is quoted in the video. I have also spoken to two people in the business representing consew and also an industrial sewing machine company doing business for 50+ years and both of them said " the machine was not designed to use a larger and heavier hand pull. Why don't you just do it the way that is widely used, proven, and readily available? "  but they were either unwilling or unable to provide what I would deem a logical and acceptable explanation as to just HOW it would damage the machine. I personally am not a technician. I have spent maybe 5 solid hours watching "consew 206rb-5 maintenance video #1, and #2 while I had my thinking cap on and tools in hand under the proverbial "hood" of my machine. This qualifies me to be classified as a "caveman holding a rock but still having to wait for lightning before I get to use fire" compared to some of you cherished lifers.  I can make no claims based on knowledge, experience, and understanding. that is why I am offering this subject up to public forum hoping some real technicians will respond and we all will learn and grow.

inside the machine there are several places that are two moving parts each with a mark someone has made that should line up when the needle is in a certain a deliberate position. is it possible that a larger wheel mean less or more revolutions so these marks will no longer line up. ergo a timing or maintenance issue reason for not using a larger pulley? obviously showing my lack of experience not knowing if that would cause more or less RPM, but im trying to understand why???

Thank you all for your time and help. I need it.

 

 

[Northmount]

There are several posts about changing the stock pulley/hand wheel on sewing machines here.  Not all of them are replacing the pulley with a pulley from a sewing machine supplier.  Some even bolt a pulley onto the side of the stock pulley.  you cn search for them here.

As for your 2nd last paragraph, how would changing a pulley on the outside of the machine change the timing of something on the inside of the machine.  As long as you don't loosen any set screws, etc. inside, or over stress anything, timing won't change due to changing an external pulley.

Tom

 

[leecopp]

I am a sewing machine newbee  compared to many here,  but in effect it is really not much different than installing a speed reducer.  There may be some safety concerns about the unguarded belt drive that a professional might want to distance himself from.  But if you can keep your fingers, hair and other bits from getting caught in the drive belt you may do just fine. 

I have installed the big ol' handwheel from a Singer 42-5 on my Seiko STH 8BLD3 and have the rig powered by a Singer 29 foot treadle. The favorable drive ratios and rotating mass allows this to work great for the heavy canvas work I do.

Have some fun

 

Lee in Florida

[Matt S]

I haven't seen that video before. I'll leave the conspiracy musings where they are (can't pick up a turd by the clean end).

It's not exactly a new idea. It's been shown several times on this forum. Some older machines used to come with a 2-speed balance wheel, like the Singer 45k.

Sure swapping a large motor pulley onto a machine'll work but there's a good few reasons it isn't ideal. In no particular order:

(1) Balance/hand wheels are designed for the hand to manipulate quickly, easily and safely, 40 hours a week. They have rounded, smooth edges raised enough that fingers, sleeves and bracelets are kept well away from the belt groove. No motor pulley I've met has any of these features. In fact it wouldn't be possible to use a pulley as a hand wheel with belt guards in place, which are mandatory in the workplace in many jurisdictions. See also the spoke design of most larger motor pulleys, which are designed to minimise mass and material, but would act as very effective finger tanglers.

(2) Balance/hand wheels act to balance the rotational speed of the machine through each stitch cycle. They do this by acting as a flywheel -- having weight around the rim, which stores rotational energy when there is an easy part of the cycle (e.g. thread take-up) and expends it into the machine during a hard part of the cycle (e.g. needle penetration). This balances out the load on the motor. The more weight the wheel has the more energy is stored. Motor pulleys are built to be as lightweight as possible, which will result in a less smooth load on the motor through each stitch cycle. How this affects a modern, cheap servo motor I'm not sure. Maybe it'll cope but I doubt it'll do it any good.

(3) Much more difficult to attach a needle synchroniser/position sensor. Very handy gadget that more people ought to use, especially if their machine is a tool of their trade.

(4) It's an unsupported (by the manufacturer's warranty) solution/modification. If you get into a crash with out-of-spec wheels on your car your insurance company's probably not going to write you a check and there may be criminal charges involved. A Ford dealership wouldn't put different wheels on your new car than it's specced for, and neither would a Consew dealer put a wheel on your machine that it's not specced for. Sewing machines are a far lower risk proposition than cars but the same principle applies, especially when you're selling and servicing them for a living.

(5) It's also not exactly slow slow -- he's only getting about a 3:1 reduction from the motor to the machine. With a 40mm pulley on the motor, a 3:1 reducer (even a £30 home-made one) and the 80mm factory hand-wheel on his machine he could achieve a 6:1 reduction if he really wanted. That's slow. He'd need a 240mm (nearly 10") diameter wheel on his machine to get this same reduction ratio with a 40mm pulley on his motor, or a 300mm (12") wheel with a 50mm (2") pulley. I've seen pictures of a Singer 111 with a 12" pulley added onto its wheel but it looked professionally modified ($£$£$£). Better just to stick all those reducer pulley gubbins under the table where thread, scissors, pens, fingers and your coffee cup aren't going to be under threat.

Now I'm no tech and I'm no dealer. Just a user that does most of his own stunts. My experience is mostly sewing leather, which is a lot tougher than a similar thickness of canvas, and I suspect that the chap who filmed that video hasn't got much experience of doing so. If it works for him, that's great. Not my cuppa tea though. Not something I'd recommend very quickly to others. And very probably not a conspiracy by sewing machine salesmen.

[wydfuqnopn]

1 hour ago, Northmount said:

There are several posts about changing the stock pulley/hand wheel on sewing machines here.  Not all of them are replacing the pulley with a pulley from a sewing machine supplier.  Some even bolt a pulley onto the side of the stock pulley.  you cn search for them here.

As for your 2nd last paragraph, how would changing a pulley on the outside of the machine change the timing of something on the inside of the machine.  As long as you don't loosen any set screws, etc. inside, or over stress anything, timing won't change due to changing an external pulley.

Tom

 

thank you for contributing. my thinking about the timing I really don't know. doesn't a small pulley go faster so the component it is connected to would go faster and if something internally is going faster or slower (a bigger pulley) then wouldn't it be tougher for the part that has the matching mark to line up with it to actually hit its mark? obviously I am such a greenhorn that I do not yet even understand the way a sewing machine works. so then I will ask you.....is there any way that putting a larger hand pull on a machine and a smaller one on the servo motor could damage the machine??? that you could think of? if so, then please explain how in you mind. thank you

 

[wydfuqnopn]

1 hour ago, leecopp said:

I am a sewing machine newbee  compared to many here,  but in effect it is really not much different than installing a speed reducer.  There may be some safety concerns about the unguarded belt drive that a professional might want to distance himself from.  But if you can keep your fingers, hair and other bits from getting caught in the drive belt you may do just fine. 

I have installed the big ol' handwheel from a Singer 42-5 on my Seiko STH 8BLD3 and have the rig powered by a Singer 29 foot treadle. The favorable drive ratios and rotating mass allows this to work great for the heavy canvas work I do.

Have some fun

 

Lee in Florida

thank you Lee. isn't that Seiko an almost exact match for the consew I have? I downloaded the manual for that one and it is much better than what consew offers.

so you have a big wheel on the same kind of machine as mine. and more effective. that's great. how long have you been operating this wy?

[wydfuqnopn]

42 minutes ago, Matt S said:

I haven't seen that video before. I'll leave the conspiracy musings where they are (can't pick up a turd by the clean end).

It's not exactly a new idea. It's been shown several times on this forum. Some older machines used to come with a 2-speed balance wheel, like the Singer 45k.

Sure swapping a large motor pulley onto a machine'll work but there's a good few reasons it isn't ideal. In no particular order:

(1) Balance/hand wheels are designed for the hand to manipulate quickly, easily and safely, 40 hours a week. They have rounded, smooth edges raised enough that fingers, sleeves and bracelets are kept well away from the belt groove. No motor pulley I've met has any of these features. In fact it wouldn't be possible to use a pulley as a hand wheel with belt guards in place, which are mandatory in the workplace in many jurisdictions. See also the spoke design of most larger motor pulleys, which are designed to minimise mass and material, but would act as very effective finger tanglers.

(2) Balance/hand wheels act to balance the rotational speed of the machine through each stitch cycle. They do this by acting as a flywheel -- having weight around the rim, which stores rotational energy when there is an easy part of the cycle (e.g. thread take-up) and expends it into the machine during a hard part of the cycle (e.g. needle penetration). This balances out the load on the motor. The more weight the wheel has the more energy is stored. Motor pulleys are built to be as lightweight as possible, which will result in a less smooth load on the motor through each stitch cycle. How this affects a modern, cheap servo motor I'm not sure. Maybe it'll cope but I doubt it'll do it any good.

(3) Much more difficult to attach a needle synchroniser/position sensor. Very handy gadget that more people ought to use, especially if their machine is a tool of their trade.

(4) It's an unsupported (by the manufacturer's warranty) solution/modification. If you get into a crash with out-of-spec wheels on your car your insurance company's probably not going to write you a check and there may be criminal charges involved. A Ford dealership wouldn't put different wheels on your new car than it's specced for, and neither would a Consew dealer put a wheel on your machine that it's not specced for. Sewing machines are a far lower risk proposition than cars but the same principle applies, especially when you're selling and servicing them for a living.

(5) It's also not exactly slow slow -- he's only getting about a 3:1 reduction from the motor to the machine. With a 40mm pulley on the motor, a 3:1 reducer (even a £30 home-made one) and the 80mm factory hand-wheel on his machine he could achieve a 6:1 reduction if he really wanted. That's slow. He'd need a 240mm (nearly 10") diameter wheel on his machine to get this same reduction ratio with a 40mm pulley on his motor, or a 300mm (12") wheel with a 50mm (2") pulley. I've seen pictures of a Singer 111 with a 12" pulley added onto its wheel but it looked professionally modified ($£$£$£). Better just to stick all those reducer pulley gubbins under the table where thread, scissors, pens, fingers and your coffee cup aren't going to be under threat.

Now I'm no tech and I'm no dealer. Just a user that does most of his own stunts. My experience is mostly sewing leather, which is a lot tougher than a similar thickness of canvas, and I suspect that the chap who filmed that video hasn't got much experience of doing so. If it works for him, that's great. Not my cuppa tea though. Not something I'd recommend very quickly to others. And very probably not a conspiracy by sewing machine salesmen.

every word you wrote made perfect sense to me. makes total sense. originally I bought a full cast iron 6" pulley but it didn't have the screws coming through it to tighten it to the shaft so I returned it and got a new one with spokes but still cast iron and heavier than the original. once I get the machine up and running again (after thread stuck in my hook and my aggressive extraction threw my machine out of whack) I will explore my set up and see where I am. in truth one of the reasons I wanted a larger wheel is because my hands are ver large and I enoy and larger wheel to tug on. thank you again for sharing

[dikman]

There's nothing particularly revolutionary in that video, he makes it sound like some sort of industry conspiracy. Basically, sellers sell reducers, usually one of two types, which do the job so I doubt if they want to bother trying to explain to customers about fitting a large replacement pulley. This way they can leave the machine intact, so it is one less area that a customer can have problems with.

Matt makes a couple of good points, but only two are really of any concern, imo. If the machine is under warranty you should probably take that into account, but there's no way that I can see that swapping to a larger pulley is going to damage the machine or the motor as long as the machine is used within its limitations. The most important one, though, is the question of safety, if you fit a large pulley and intend to do handwheeling make sure your foot is off the pedal before touching the wheel!!!!

At the slow speeds most of us are looking for any "flywheel effect" is going to be irrelevant, besides which the weight of your pulley isn't likely to be that much more than the one you took off. I have fitted a quite heavy pulley on one of my machines and it works fine, I also have had no problems getting a 4:1 reduction using this method, and while it is fine with one servo with a different brand it wasn't good enough, so I fitted a reducer too and am getting 11:1 reduction.

As for the timing, as Tom said as long as nothing is changed inside the machine doing this cannot affect the timing!

Industrial machines are built to take lot of abuse and to keep working day in, day out under conditions that we are unlikely to subject them to. Slowing them down, whether with a reducer or a large pulley, is going to significantly reduce the wear on a machine.

In short, you are worrying unnecessarily.

[Constabulary]

Putting in my worthless 2 cents...

There also is an esthetical aspect for using a speed reducer. I personally do not like the large or oversized pulleys (w/o the hand wheel rim) on a sewing machine - I find it kind of ugly - but thats just me. For me, when ever possible, a machine should look like as if it came from the factory. It´s like driving an AMC Pacer - it drives an takes you from A to B but its ugly and you have to look at it day in and day out. If you consider a sewing machine just as a tool for doing a certain job then there nothing wrong with a large pulley on a sewing machine but for me it would not be the way to go / to slow down the machine - just for optical reasons. If it´s all under the table its more "eye friendly " for me

Don´t get me wrong - no offense to people who have large pulleys on they machines

For instance - this thing would drive me nuts

 

Edited November 11, 2018 by Constabulary

[leecopp]

6 hours ago, wydfuqnopn said:

thank you Lee. isn't that Seiko an almost exact match for the consew I have?  

so you have a big wheel on the same kind of machine as mine. and more effective. that's great.

Yep pretty much the same as the consew unit.

Yes the larger handwheel made the difference. It would not treadle with the stock handwheel. You could distinctly feel the cyclic loading and it would bog down the treadle.  With the huge rotational mass of the 42-5 handwheel  and the larger diameter of the associated pulley, the whole rig works..  I have been using this configuration for a couple years.  I sew as a hobby and I am not in a "production" environment.

I do not sew leather with this rig but do some heavy canvas work.

[DonInReno]

That guy is just trying to get more views claiming he’s discovered something unique....nothing he claims is revolutionary, difficult or a conspiracy.  Of course sewing machine dealers won’t encourage modifying a machine - somebody’s grand kid puts his fingers in the new pulley and guess who gets sued.  There is no upside for a dealer to sell anything except what normally comes with a machine.

I’m in favor of improving the performance of a machine if it’s done in a way that demonstrates good judgement and craftsmanship.  If someone cobbles together an abortion I have no desire to be the good judgement police - to each his own.

edit:  A larger handwheel won’t affect timing, but it does make it more likely that a needle crash or jam will screw up the timing since there’s more torque being applied.

Edited November 12, 2018 by DonInReno

[dikman]

9 hours ago, DonInReno said:

edit:  A larger handwheel won’t affect timing, but it does make it more likely that a needle crash or jam will screw up the timing since there’s more torque being applied.

True, but the same thing can happen with a reducer, it's simply a different way to achieve the same result, i.e. slow down the machine.