Thread: Vacuum Chucks

Originally Posted by smiife

Hi dave,
Yeah the web address Is....www.woodturnerscatalog.com
It Is from craft supplies usa.
the price on the web site is US $288
It, s called a holdfast vacuum system
and works a treat, I have never had any problems
with the system and never lost a bowl...........yet
(Fingers crossed)
Hope this helps you and others
Cheers smiife

thanks, I'll check that out now .... what is the advantage of this system over a vacuum pump ... I have not priced a vacuum pump - maybe they cost more than I thought.

This is one of those things I thought it would be nice to get eventually


Dave the turning cowboy

turning wood into art

Originally Posted by DaveTTC

thanks, I'll check that out now .... what is the advantage of this system over a vacuum pump ... I have not priced a vacuum pump - maybe they cost more than I thought.
This is one of those things I thought it would be nice to get eventually
Dave the turning cowboy
turning wood into art

Dave, the main advantage to the HoldFast vacuum generator seems to be ease of setup.

A vacuum pump costs $100, a vacuum gauge about $20 delivered, a lever ball valve for vacuum release/adjustment $10-$20, a double-sealed bearing <$5, an air filter $11, then hose and fittings, plus some turning for the vacuum cup(s) and handwheel fitting.

A link to the pump I bought: http://www.ebay.com.au/itm/Electric-...#ht_4004wt_996
There's still 3 left at this price - all others are dearer.

A link to the air filter as used in TTIT's setup: http://www.ebay.com.au/itm/NEW-Auto-...#ht_1671wt_926

" " " a gauge: http://www.ebay.com.au/itm/Vacuum-Ga...item19df72f2f3

This (UK) supplier, (where the gauge comes from), has heaps of fittings, hose, etc.: http://www.ebay.com.au/sch/context-p...p2047675.l2562
(You might be able to find this stuff locally - I was lucky and a mate in Sydney is giving me most of what I need.)

If you read back through the last couple of pages you'll find a bit more info.

Also, I've attached a pdf originally provided by Cliff earlier in the thread that provides some more useful info on building one. It's worth saving a copy of this, if you go the DIY route.

Originally Posted by DaveTC

thanks, I'll check that out now .... what is the advantage of this system over a vacuum pump ... I have not priced a vacuum pump - maybe they cost more than I thought.

This is one of those things I thought it would be nice to get eventually


Dave the turning cowboy

turning wood into art

Hi dave,
I think hermit may have already answered your question Too late again...
The only advantage I thought about was that I already had a air compressor
so I guess if you don, t have one , you would have to price both options

Originally Posted by smiife

Hi dave,
I think hermit may have already answered your question Too late again...
The only advantage I thought about was that I already had a air compressor
so I guess if you don, t have one , you would have to price both options

Sorry if I stepped on your toes, Michael, but after doing all that hunting for sources of the various bits, I wanted to share the knowledge.

Regarding a compressor for running the vacuum generator, apparently it needs to be a decent size to maintain enough constant pressure, too, according to that 'Vacuum Chuck Demo' pdf.
(Definitely not my little old beast.)

QUOtE=Hermit;1769667]Sorry if I stepped on your toes, Michael, but after doing all that hunting for sources of the various bits, I wanted to share the knowledge.

Regarding a compressor for running the vacuum generator, apparently it needs to be a decent size to maintain enough constant pressure, too, according to that 'Vacuum Chuck Demo' pdf.
(Definitely not my little old beast.)[/QUOTE]

Hi hermit
No toes hurt here mate
All INfo gathered helps everone interested
and also sharing our knowledge with each other
Is what this forum Is all about isn, t it ?
I think the compressor capacity needs to be at least 60psi

Originally Posted by smiife

Hi hermit
No toes hurt here mate
All INfo gathered helps everone interested
and also sharing our knowledge with each other
Is what this forum Is all about isn, t it ?
I think the compressor capacity needs to be at least 60psi

I didn't put it very well - I meant the size rather than pressure of the compressor, so that it can maintain the needed pressure without running full-time. Noisy, if nothing else.

Edit: Covered in section 5.3 of that pdf

Originally Posted by Hermit

I didn't put it very well - I meant the size rather than pressure of the compressor, so that it can maintain the needed pressure without running full-time. Noisy, if nothing else.

Yeah they can get a bit noisy,,,,,,,
I have mine 20 metres away under the house
and my dust extractor is outside the shed too......
So It annoys the neighbours and not me

I had toyed with the idea of vacuum chucking for some time before coming up with the following.

The handwheel on my Nova lathe will fit a standard size bearing. There is already a threaded hole to secure it in place with a grub screw.
Image00001.jpg

I made up a wooden adapter to fit the end of a vacuum cleaner hose and a snug fit to the inside of the ball bearing.

Image00004.jpg


The spindle is free to turn while the hose remains stationary. Just in case it gets knocked out, I usually tape it to a support. The vacuum cleaner hose has a sliding "bleeder" valve which I leave slightly open to prevent the vacuum cleaner from overheating.
Image00002.jpg

I bought a "Beall" spindle tap to suit my lathe and made up a number of different sized chucks with a circular rebate to which I glued some closed cell rubber piping. Works a treat! No need to worry about sucking in some dust - that's what the vacuum cleaner was made for.

Image00003.jpg

Total Cost
Bearing - about $2
Rubber - about $5
Beall Spindle tap - $28 (+$10 postage from US)

Originally Posted by nalmo

I had toyed with the idea of vacuum chucking for some time before coming up with the following.......

My original thought was to simply use a vacuum cleaner, but everyone and everything I read told me that it would burn the motor out due to insufficient air flow, even with the bleeder open.

You might have struck it lucky with a vacuum cleaner that can handle it.

What's it like for extra-thin-walled bowls? No crushing?

And no UFO's when turning a tenon off the bottom?

Nalmo

Where did you get your spindle tap ... I got the wrong size from the states. Mine is 1" x 8TPI but I have a NOVA 3000 so should be the same as yours


Dave the turning cowboy

turning wood into art

Originally Posted by DaveTTC

Nalmo

Where did you get your spindle tap ... I got the wrong size from the states. Mine is 1" x 8TPI but I have a NOVA 3000 so should be the same as yours


Dave the turning cowboy

turning wood into art

Dave, I got the spindle tap from Lee Valley in US (from memory, surface postage was about $10), I have 1-1/4 x 8 spindle thread (Nova 1624).

So far, I've had no problems with flying saucers. The bowls are held on very firmly with the bleeder open a small way. For thin walls (which I haven't tried yet), I'd just open it a bit further. The ball bearing is not an airtight seal, nor is the rubber bead. wouldn't be too hard to introduce a few small point for leakage if you were concerned. I have not been able to budge the item with the vacuum running.

I checked the temp of air coming out of the vacuum cleaner outlet. Slightly warm, but not more so than when used for cleaning the house.
I bring up the tail stock to secure the piece once the lathe stops turning, turn off the vacuum, then I don't have to leave the vacuum running & reposition the piece when I continue turning.

Originally Posted by nalmo

Dave, I got the spindle tap from Lee Valley in US (from memory, surface postage was about $10), I have 1-1/4 x 8 spindle thread (Nova 1624).

So far, I've had no problems with flying saucers. The bowls are held on very firmly with the bleeder open a small way. For thin walls (which I haven't tried yet), I'd just open it a bit further. The ball bearing is not an airtight seal, nor is the rubber bead. wouldn't be too hard to introduce a few small point for leakage if you were concerned. I have not been able to budge the item with the vacuum running.

I checked the temp of air coming out of the vacuum cleaner outlet. Slightly warm, but not more so than when used for cleaning the house.
I bring up the tail stock to secure the piece once the lathe stops turning, turn off the vacuum, then I don't have to reposition the piece when I continue turning.

Interesting. There are definitely two schools of thought on the subject.
My (Piranha) vacuum cleaner wouldn't be very suitable. It has a valve built into the top that sucks air heavily if the paper filter is clogged, and it also has a temperature cutout switch built in. I used to use it on my OSS before I bought a DC, and it would turn itself off after about 15min of fine dust and would take a couple of hours to 'reset'. The last thing you want is to have the vac shut down mid-turning. That could be bypassed though, I guess.
Either way, I've already shelled out for a vacuum pump which should be here tomorrow or Wednesday.

Interesting thought .... DC system .... could you divert a line of your DC to use for vacuum chucking. I have a DC not set up yet. I guess it would be hard to regulate and know how much pressure you really have


Dave the turning cowboy

turning wood into art

Originally Posted by DaveTTC

Interesting thought .... DC system .... could you divert a line of your DC to use for vacuum chucking. I have a DC not set up yet. I guess it would be hard to regulate and know how much pressure you really have
Dave the turning cowboy
turning wood into art

Good question Dave. A bit outside my comfort zone, but the man to ask would be BobL, who usually hangs out in the Dust Extraction forum.
I don't think my little 1000W, 100cfm DC would be much good - it gets pretty hot if the paper filter is clogged. Like a vacuum cleaner, it relies on air flow through the motor for cooling, too.
If it's likely to work, you could probably add a vacuum gauge.