Thread: Pulleys

Originally Posted by Pauls321

Hi all again, well my pulleys turned up yesterday, my motor/s haven't arrived yet but hoping the pulleys fit ok. However upon looking at the pulleys, they dont have a grub screw to tighten them onto the shaft.

I've messaged the seller (ebay bloke), but I doubt that will do anything, asking him how they are tightened to the shaft.

This is what they look like.

eBay Australia: Buy new & used fashion, electronics & home d

Any suggestions. I was thinking I might have to drill a hole through the bottom of where the belt sits and tap a thread into it, then purchase a grub screw,..??

Regards, Paul

You might have a problem. Since the pulleys have a slot for a woodruff key, they might be a tapered fit, intended for a shaft with a taper and a thread for a nut at the end. Is the hole through the pulleys the same ID right through, or does it get narrower?

Hey there Humphrey, Thanks again for your reply. I just checked the internal diameter with my calipers. The thread is the same id all the way through, precisely 24mm.

I found a pulley site last night on the net describing various ways of attaching pulleys to motor shafts. One way was what I was thinking. Saying that where there is no built in grub screw you can drill down through the bottom of where there V belt would lie, and tap a thread. then insert your grub screw ensuring it was under the surface of the pulley (naturally).

I've got one hand tap, it's a 5/16, maybe a bit to large, will have to have a think about this,

Regards, Paul

Originally Posted by Pauls321

Hey there Humphrey, Thanks again for your reply. I just checked the internal diameter with my calipers. The thread is the same id all the way through, precisely 24mm.

I found a pulley site last night on the net describing various ways of attaching pulleys to motor shafts. One way was what I was thinking. Saying that where there is no built in grub screw you can drill down through the bottom of where there V belt would lie, and tap a thread. then insert your grub screw ensuring it was under the surface of the pulley (naturally).

I've got one hand tap, it's a 5/16, maybe a bit to large, will have to have a think about this,

Regards, Paul

Glad they're not tapered shafts.
It's a long way to the shaft if you drill from the bottom of the 'v' groove. The grub screw would need to be about 40mm long, wouldn't it? It would also be going through some thin material sideways, by the look.

It would be better to drill from closer. Is it possible to drill/tap from here?: -
pulley drilling.jpg

Hi again Humphrey,

Just pushing aside the installing of these pulleys for a minute, still working on that. I have been thinking about this overall rpm speed, and the 2100 rpm that we discussed earlier in this thread. Looking at the youtube clipping on the pulley I am building, which is

Thickness sander - YouTube

This seems to spin at a lot less than say 2100rpm. Looking at the plans again, link was shown earlier, it works on a 1750 rpm motor with a 2 inch pulley to drive a 5 inch driven pulley. That works out at 700 rpm, which to me seems about right watching that youtube clipping.

Of course your speed with your H&F one with the conveyer belt on it also, would most likely be heaps faster.

Regards, Paul

Originally Posted by Pauls321

Hi again Humphrey,

Just pushing aside the installing of these pulleys for a minute, still working on that. I have been thinking about this overall rpm speed, and the 2100 rpm that we discussed earlier in this thread. Looking at the youtube clipping on the pulley I am building, which is

Thickness sander - YouTube

This seems to spin at a lot less than say 2100rpm. Looking at the plans again, link was shown earlier, it works on a 1750 rpm motor with a 2 inch pulley to drive a 5 inch driven pulley. That works out at 700 rpm, which to me seems about right watching that youtube clipping.

Of course your speed with your H&F one with the conveyer belt on it also, would most likely be heaps faster.

Regards, Paul

I just replied once, but everything locked up and the browser crashed. Second time lucky.....

I'd say any speed would work. If the drum is turning, it will sand.
I noticed the other day that the original of the one you're building was geared down quite a bit, to run at a pretty low speed.

Higher speed, similar to a commercial one, would be faster and would allow you to take off more material per pass, but on the other hand would be potentially more dangerous. Take your pick.

Commercial units also employ a pair of spring-set pressure rollers to keep the material firmly held down, too. Mainly, I guess, for the conveyor belt, but it also helps prevent possible kickback if the material contacts the drum slightly high and digs in. The downside of these rollers is slight snipe at the beginning and end of a cut, when only one roller is pushing down.

The best way of attaching a pulley to a shaft is by using the keyway. Your motor will most probably have a keyway too. The only real problem is if the keyways are a different size. Square key material is quite easily purchased. Just cut it to length. Keyways are easier than grub screws and more secure. Engineering firms can easily put keyways into place if they arenot already there with a broach.

Woodruff keys from memory are like a half round profile. You won't need that here.

A drum sander is a very enterprising build. Good luck and keep up the good work.

Regards
Paul

Originally Posted by Bushmiller

The best way of attaching a pulley to a shaft is by using the keyway. Your motor will most probably have a keyway too. The only real problem is if the keyways are a different size. Square key material is quite easily purchased. Just cut it to length. Keyways are easier than grub screws and more secure. Engineering firms can easily put keyways into place if they arenot already there with a broach.

Woodruff keys from memory are like a half round profile. You won't need that here.

A drum sander is a very enterprising build. Good luck and keep up the good work.

Regards
Paul

Thanks, Paul, I just learned something.

I was referring to a square key, but thought they were all called 'Woodruff' keys, regardless of shape.

Hi Humphrey and Paul, this is becoming interesting, frustrating, but interesting. The motor/s that I have purchased which will hopefully arrive here by the end of this week with my son, have a built in key attrached to the shaft. My son tells me that this key is raised about 4mm from the shaft and about 6mm across,...BUT, it DOES NOT extend the full length of the shaft, (naturally,..!).

There is a small space of 5 or so mm between the actual motor and the key, then the same sort of distance from the end of the key to the end of the shaft. It is looking like a grub screw will be necessary to keep all this in place.

I was looking at that youtube video compiled by a chap named Pat, over in the USA, the guitar maker. I emailed Pat via his guitar site and he sent back a very nice reply. Told me that his home made thickness sander has a 1725 rpm motor with a 2" and 5" pulley. This gives it a speed of 690 rpm on the top shaft. Then for some reason he told me he also recently purchased a Ryobi drum sander where the motor which is also 1725 rpm connected directly to the drum shaft. As Pat said that one rotates much faster than his home made model. He also said that both outfits work very well and in his opinion it doesn't matter a lot on the speed, you get to know how fast you can push the timber through depending on hardness of the timber and the grit of the paper.

The pulleys I purchased are to fit a 24mm shaft, so still tossing around in my head about that aspect. The outside diameter of my drum shaft (chromed steel rod) is 25mm, I would love to be able to use one of my pulleys on that,....hmmm..!,..still thinking.

And then on top of that, my old bandsaw that the motor died on me, I took the motor up to Coffs Power Tools, hadnt heard back from them, got my son to pick up two of those motors in Sydney,...........called in to Coffs Power Tools on friday to bring my old motor back home, (needed the switch etc from it), it was repaired, needed a new capacitor $12 and $30 labour, 42 bucks,...geeeez. Now I have a spare brand new motor. Any suggestions on something else I can build with it down the track..?

Regards, Paul

Originally Posted by Pauls321

He also said that both outfits work very well and in his opinion it doesn't matter a lot on the speed, you get to know how fast you can push the timber through depending on hardness of the timber and the grit of the paper.

Hmmm. If his home-made one is so good, why did he then lash out and buy one, I wonder? If speed isn't too important, I'd definitely go with the slower speeds for a DIY unit, for safety.

The pulleys I purchased are to fit a 24mm shaft, so still tossing around in my head about that aspect. The outside diameter of my drum shaft (chromed steel rod) is 25mm, I would love to be able to use one of my pulleys on that,....hmmm..!,..still thinking.

You need to urgently befriend a metal machinist. I mentioned GT Engineering the other day. They'll do all that sort of stuff, but it costs.

And then on top of that, my old bandsaw that the motor died on me, I took the motor up to Coffs Power Tools, hadnt heard back from them, got my son to pick up two of those motors in Sydney,...........called in to Coffs Power Tools on friday to bring my old motor back home, (needed the switch etc from it), it was repaired, needed a new capacitor $12 and $30 labour, 42 bucks,...geeeez. Now I have a spare brand new motor. Any suggestions on something else I can build with it down the track..?
Regards, Paul

Hang onto that extra motor. You could make a nice 12" disc sander. It'll be useful for something, even if you keep it as a spare for the bandsaw or drum sander. (Or you could give it to me.)

Edit: I forgot to add, my drum is direct-driven by the motor too.

hi paul i was wondering if you asked pat how the disc on the drum were held in place are they glued ,keyed or by some other way? or how have you done it?
thanks camel very interesting so far.

Hi Camele, and Humphrey, and others. I just typed out a long reply and lost it all on IE9, trying google chrome web browser now. Camele, thanks for your comments. In relation to the discs on drum shaft. I purchased a length of 25mm chromed steel, 900mm long from Mitre Ten. I used 700mm of this. I cut out 30 x 130mm diam pieces of 16mm mdf, make sure you can see your centre dot clearly, then I drilled a hole through all of these with a 1" spade bit. If you put just 1 of these onto my 25mm shaft it does spin, I guess the difference between 25mm and 1 inch. I used Selleys rapid set aquadhere and glued 3 circles on initially, lining up the first one, and the result was perfect. They did not move at all. I then continued and did these in lots of 3 as it only takes that glue about an hour to set, until I did all the 30 of them. Clamping them into my triton super jaws and also a bar clamp. There is no way in the world they will move or turn on the shaft. I would never be able to get them off again. I guess its the pressure of 30 being glued together plus some of my glue running onto the shaft.

My motor/s have now arrived and I have put that 70mm double pulley on, (link to site previously shown) and it fits perfect. I even had to use a bar clamp to push the pulley onto the shaft, the key fitted perfect also, it will never budge. Today I drove up to Coffs Harbour and boughty my belt, but still waiting on my pillow blocks to arrive from hong kong. Tomorrow I am going to a mate's place to use his lathe the make up my timber pulley for the drum shaft, I hope to end up with a speed of about 1000 rpm. I am also going to true up my drum (mdf pieces) on his lathe also, but will still do the final sand when my outfit is all finished.

Pat did tell me that he purchased a Ryobi drum sander as he picked up a second hand one for $300 in excellent condition and they were selling for around the grand mark. Said that Ryobi don't make that model anymore.

Fingers crossed mine works okay at the end of all this. I really only want to be able to thickness/sand timber to between 6mm and 12mm just to make jewellery boxes, my latest passion. Having made all the timber furniture for this house (and leadlight also), I run out of projects. Around the traps over recent months I picked up a heap of timber.

For anyone else reading this thread, if your interested in my other brand new motor let me know. They are certainly an excellent motor, 2HP and 1400rpm. Not sure what I will do with it yet.

Also today at Coffs Harbour I called in to Gasweld and ended up purchasing a 1HP dust collector, seems a very good outfit. A portable under the bench type model, only takes up about 400x400 floor space, should tuck nearly away under and old dressing table that I have converted into my makita compound mitre saw table.

I should have bought one of these years ago.

Regards, Paul

It's sounding good, Paul. All coming together nicely.

At least now you know that Pat bought the Ryobi because it was so cheap, (I'd have bought it too), and not because his DIY drum sander wasn't good enough.

You're following a similar path to me - I made a router sled, then decided I'd like a thicknesser but wouldn't like the noise, so bought the drum sander for minor thicknessing and finishing, after planing with the router sled.

The drum sander is also better for burls etc that might otherwise shatter on a thicknesser.

Keep up the good work, and keep us posted.

Hey there Humphrey, Very interesting, I actually made a router sled also, a few months ago. The photos of it would be on another thread of mine in this site somewhere.

https://www.woodworkforums.com/f88/ma...r-sled-152826/

Just found it. It does work rather well and if you follow that thread you will note my sled also has a sanding facility as well. All self explanatory in that thread. Why am I building a drum sander now, good question, just trying to think of an answer,....!! Maybe I just like the challenge.

Here is the thread on my router table I also built earlier this year

https://www.woodworkforums.com/f15/tr...in-jig-145901/

That router table is awesome, love it, just so simple to use, beats my old triton router table and old makita router where I practically had to stand on my head to change the bits. But I keep that old router table and router purely to use with the triton biscuit jointer, used it countless times over the years.

Like I said, maybe I just like the challenge, another interest of mine is creating horse racing systems on excel and just creating the spreadsheet at times takes over the actual part of the hobby above the system itself.

Keeps the old brain ticking over..!!

Regars, Paul

I read your router sled thread a couple of days ago.

Mine's a miniature version - uses a Dremel plunge router. Also has sanding capability, EZLock discs, but even fine 240 grit discs leave circular sanding marks. Hence the drum sander. Mind you, there isn't much cleanup needed after router planing.
A drum sander is also far faster than thicknessing with a router sled, with coarse paper. I've got grits down to 60G, but 36G is available.


Have you worked out a system for fast-changing the drum sander belts, for different grits? The finer grits are helpful, because drum sanders inherently leave grooves the length of the board. I'd love an oscillating wide drum sander - it wouldn't leave the grooves, but I don't know if there's such an animal.
240G on the drum sander cleans things up pretty well, and only a fine finishing sand is needed afterwards.