Putting some grip (stippling) on an aluminium drive pulley.

[JimDobson]

the farmers don't have a slack belt intentionally and definitely not when under high load but the belt weight on a 100 ft 6inch wide flat belt 3/8 thick kind of sags itself and provides a lot of tension on the pulley faces the stippling does work a little more tough on the belt but its a model not a production machine a safer method would be using a purpose built handle for the saw blade or maybe just chuck it in the dremel and let the dremel free wheel

That's a very good suggestion, blindingly obvious, but not thought of by myself. Thanks!

 

[terryd]

Instead of using a dremel saw blade you could get a leather marking wheel use for marking out stitch spacing as used by sadlers and leatherworkers. Cheap ones are available on eBay and they would easily manage on aluminium. Having a proper handle makes the job so much safer.
TerryD



ea

 

[goldstar31]

Instead of using a dremel saw blade you could get a leather marking wheel use for marking out stitch spacing as used by sadlers and leatherworkers. Cheap ones are available on eBay and they would easily manage on aluminium. Having a proper handle makes the job so much safer.
TerryD



eaView attachment 120232

I'd actually forgotten that I once could do a 'Holbein' stitch.

 

[k2steve]

I don't know why a lot of these negative post bother me so much, I do not see a problem with how Jim did his thing. I am guessing that these negative folks don't catch there part with a hand when parting off or use emery paper on there part next to the chuck while its rotating.

 

[ALEX1952]

The leather belts which were joined with a wire "lace" which. if used on a machine such as the old smart and brown lathes on which I learnt my trade, with slack in the head stock bearings, it would probably produce a mark in your work given the right circumstances. There is a lot to be said for learning on a worn out machine, it teaches you to work round the short comings of equipment and still turn out a good job without throwing money at it. Now the only thing knackered is me bad hear,t cancer remission, age etc but we work round it.

 

[BaronJ]

I don't know why a lot of these negative post bother me so much, I do not see a problem with how Jim did his thing. I am guessing that these negative folks don't catch there part with a hand when parting off or use emery paper on there part next to the chuck while its rotating.

That depends upon how much you value parts of your anatomy !

Personally I think that it is wrong to pass on these dangerous techniques to those who may not know any better ! Now if the video showed the job done safely it would be a different matter.

 

[IanN]

That depends upon how much you value parts of your anatomy !

Personally I think that it is wrong to pass on these dangerous techniques to those who may not know any better

Hi,

I agree with BaronJ - many people trust and rely on the content of forums such as this (yes, I know it is crazy to trust a random idiot posting on the internet but people really do - said by a random idiot...)

Sooner or later an inexperienced newcomer will follow a “bright idea” and get seriously injured. When that happens, I would guess that there will be repercussions for a forum such as this (we live in an ever increasingly litigious society)

I teach apprentices. After five years of college and industrial engineering experience they are deemed to be newly qualified engineers/machinists. This has taken 40 hrs a week for five years = 2000 (approx) on the job hours. If you are a keen amateur and spend a couple of hours every evening, every day, every week, in your workshop (700 hrs per year) it will take you almost 30 years to get the same level of experience as a newly qualified apprentice (assuming you have also studied the text books and passed the theory exams too)

My point is that we should be very careful what advice we give to people with no prior knowledge, no prior experience and no one looking over their shoulder guiding their every move

Ian

 

[JimDobson]

Really happy how quick and easy this method worked for giving that extra grip that can sometimes be needed on such small pulleys that are on model and toy steam engines and the accessories that can be run off them.

 

[JimDobson]

And to quote good old John Moore (Bogstandard, jeez I miss him) from the sticky at the top of the Tips & Tricks section -

"For all of us who have a bit of experience and those who don't have as much, this topic is here to show people how we do things, there might be other ways, buts lets see how you do it.
We don't all have the tooling required in the shape of millers, surface grinders etc, but most people should have a lathe. So lets show members how to use the machinery we have to make those elusive little bits.
Nothing is too mediocre for this section, even if it is how to get the stuck on top off a superglue bottle, without mashing the top (if anyone has a solution to that, let me know), lets hear about how you do it.
Let's help people make little engines, don't hide your little secrets, share them, it doesn't cost you anything except a little time.
It just might help someone over the hurdle of finding a way to get that little engine finished".

 

[JimDobson]

Instead of using a dremel saw blade you could get a leather marking wheel use for marking out stitch spacing as used by sadlers and leatherworkers. Cheap ones are available on eBay and they would easily manage on aluminium. Having a proper handle makes the job so much safer.
TerryD

Yeah, I could have bought and paid for a whole lot of things and waited for them to arrive to use that may or may not have worked as well.
Sometimes you use what you have at hand.
Necessity is the mother of invention ........ as the saying going.

 

[terryd]

I don't know why a lot of these negative post bother me so much, I do not see a problem with how Jim did his thing. I am guessing that these negative folks don't catch there part with a hand when parting off or use emery paper on there part next to the chuck while its rotating.

Hi Steve

People aren't necessarily criticising, rather they are advising.
I worked in the engineering industry before H&S was taken really seriously. There were many operatives who had lost parts of fingers, even whole fingers and hands. There were those who lost the use of an eye. I could go on and on and relate the range of sometimes horrendous injuries but that would need an essay. The majority of these injuries were caused by taking short cuts or using techniques such as we have seen here.

By the way, most of the parts caught when parting off in our hobby are mostly small and circular with low energy when finally cut, But I usually catch my parting off with a small round bar (such as a key used to replace carbide tips) in the borea. When using abrasive cloth (not paper) I and most others would not go anywhere near the rotating chuck with a small piece, I use a long strip of emery cloth, long enough to allow me to hold both ends well away, not allowing it to become wrapped around the part. I have been using rotating machinery at home and work for almost 50 years and still have all of my physical faculties.

TerryD

 

[JimDobson]

Hi Steve

People aren't necessarily criticising, rather they are advising.
I worked in the engineering industry before H&S was taken really seriously. There were many operatives who had lost parts of fingers, even whole fingers and hands. There were those who lost the use of an eye. I could go on and on and relate the range of sometimes horrendous injuries but that would need an essay. The majority of these injuries were caused by taking short cuts or using techniques such as we have seen here.

By the way, most of the parts caught when parting off in our hobby are mostly small and circular with low energy when finally cut, But I usually catch my parting off with a small round bar (such as a key used to replace carbide tips) in the borea. When using abrasive cloth (not paper) I and most others would not go anywhere near the rotating chuck with a small piece, I use a long strip of emery cloth, long enough to allow me to hold both ends well away, not allowing it to become wrapped around the part. I have been using rotating machinery at home and work for almost 50 years and still have all of my physical faculties.

TerryD

Mate, you're going over the top. Its a 1" dremel saw blade held by its arbor with a pair of multigrips.

 

[Cogsy]

I'm also struggling to see what people are getting so worked up about here. The 'cutter' was being held in a pair of multigrips (which I often trust enough to do various jobs involving molten metal work and have a far more reliable handle than a wooden leatherworking tool) so hands were nowhere near the spinning chuck, which is the biggest hazard in my opinion. Plus, the 'cutter' itself was a very low weight blade and not spinning at terribly high RPM, so it had little rotational momentum. If he had let the thing go while in contact with the part, it would (in my estimation) been kicked away from the workpiece and very quickly stopped rotating. If it had somehow contacted skin before it stopped it contained so little energy that it was unlikely to do any damage. As long as he was wearing eye protection I don't think there was much risk.

I feel a lot more anxiety when I use the abrasive disks or grinding attachments that fit the Dremel-type machines. They spin up to something scary like 35,000 RPM and will sometimes just explode into projectiles if they encounter a jam or are just poorly made.

 

[BaronJ]

Guys, you are missing the point !

It is not a safe practice and it has no place in a video that is going to be seen by many people that will think that it is OK to do things that way. The fact that it was a tiny wheel is not the point !

 

[JimDobson]

Guys, you are missing the point !

No, I reckon that's you.

 

[coulsea]

I think that this is a good solution for this application but I think that in general people who make videos and publish them do have a responsibility for the information that they offer. A short explanation of why you think that there is little risk for you in this application. If you don't see that there is any risk of the next person using a 6 inch blade supported by a pencil then maybe you should not be publishing videos. Not trying to pick on Jim but generally if you wouldn't publish it in a book, don't publish it in a video that can be seen by everyone, forever.

 

[JimDobson]

I think that this is a good solution for this application but I think that in general people who make videos and publish them do have a responsibility for the information that they offer. A short explanation of why you think that there is little risk for you in this application. If you don't see that there is any risk of the next person using a 6 inch blade supported by a pencil then maybe you should not be publishing videos. Not trying to pick on Jim but generally if you wouldn't publish it in a book, don't publish it in a video that can be seen by everyone, forever.

Once again, just completely over the top response.

 

[minh-thanh]

My opinion :
From my memory, I seem to have tried it the same way as JimDobson .
And another couple of times with some seemingly unsafe way
But then I always find a way to hold back and limit if something goes wrong
But, let's say: If a person is completely new (or very inexperienced , or he doesn't notice speed ... ...) and has a lathe, and he does the same but at a higher speed (500, 1000 rpm ..) and what What happens when he makes a mistake ??
I'm not saying I always do one thing safely, but with my little experience it seems to be okay for people who have already experienced , it's not for the novice.

 

[Cogsy]

Guys, you are missing the point !

It is not a safe practice and it has no place in a video that is going to be seen by many people that will think that it is OK to do things that way. The fact that it was a tiny wheel is not the point !

But if it wasn't the tool that he used that you have an issue with then was it simply the practice of hand-holding tool on a metal lathe? There are plenty of videos of graving and metal spinning where they do just that and no-one suggests these videos are not appropriate. What exactly is the issue here?

 

[JimDobson]

Hope no one who's complaining has ever put a file near a spinning lathe. I know I do....regularly.