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dai sensei
18th January 2012, 07:45 PM
After attending 's "Grippy things" weekend :2tsup: I realised how easy it was to make a vacuum chuck for the lathe. So over Xmas when someone asked me to make a natural edge "bowl thingy" from some Hairy Oak and I was up to finishing the base, I thought to myself, perfect excuse to make a vacuum chuck :wink:. In my normal fashion, I then thought, why make one when you can make four different sized ones :rolleyes:

I pulled out a small sheet of 19mm formply and sliced it up into smalled squares. I use 75sq for a tennon on the chuck, 2 squares each tennon, then 3 each of the other sizes for the different sized chuck faces. I glued up the chuck pieces and tennon pieces separately with Titebond II.

The tennons are made by turning between centres then drilling them, soak with thin CA, then tap 30x3.5 (both my lathes have this thread) all the way through, soak again with thin CA, then tap again. I then glued the tennons to the chuck face pieces. Whilst on the lathe, I then turned the face to shape including a grove to seat the rubber seal, and the tennons to true. Then I gave them all with a few coats of shellac.

Finally I glued in the rubber seal, from 6mm rubber round for the smaller two and 10mm rubber round for the larger two, and a small flat of rubber at the base of the tennon.

Finished chucks are 50mm, 120mm, 200mm and 300mm chucks.

More on the lathe connections next.

dai sensei
18th January 2012, 07:52 PM
For the lathes it is a matter of a bearing with a small PVC conduit fixed into the bearing, fixed into a timber plug. For the JET I screwed the plug to the flywheel. For the Woodfast I made a plug that seated into the cone shaped flywheel, with a rubber seal against the inside base of the flywheel.

Next was a set-up for a mini vacuum pump connected to my air compressor, the other for my electric vacuum pump, both connecting to the PVC conduit on the lathes (simply push on). The photos show one on each lathe, both both can be used on both lathes. They also both pull a 29.9" vacuum, just the electric one pulls very fast, whereas the air one takes a while :-.

Also shown is the natural edge bowl thingy I started making the chucks for, mounted on the 50mm chuck.

Cheers

RETIRED
18th January 2012, 09:15 PM
Looks like the hand of fate.:wink:

Sturdee
18th January 2012, 09:55 PM
Next was a set-up for a mini vacuum pump connected to my air compressor, the other for my electric vacuum pump,
Cheers

Neil,

Can you give us more details on the vacuum pumps.


Peter.

dai sensei
18th January 2012, 10:18 PM
Neil,

Can you give us more details on the vacuum pumps.


Peter.

Below is a photo of my electric one, bought off a guy in Sydney ~$150, Ebay sells similar. The other air operated one is a simple (but good one) venturii pump, bought from an air specialist business in Brisbane (that went broke last year) ~$100.

The air one takes longer to draw a decent vacuum, so the electric is definitely better. At 's place a vacuum cleaner was used sucessfully, doesn't pull the same vacuum, but for the larger chucks it is fine. Definately need a decent vacuum for the 50mm one, as smaller area means less holding force.

Cheers

GPW
18th January 2012, 10:37 PM
Hey Neil

You may need to be careful with the extra load placed on your bearings.

TTIT
18th January 2012, 10:38 PM
Good stuff Neil :2tsup: Be very careful though if you're pulling up to 29" - I crushed a couple of thin bowls by getting over-zealous with the vacuum. These days I regulate it to no more than 15" to 20" unless it's holding a very solid item.

dai sensei
18th January 2012, 10:40 PM
Good point, definately not going to hold my egg forms

Scott
18th January 2012, 10:57 PM
You've got me rubbing my chin, thanks for posting.

issatree
19th January 2012, 01:30 AM
Hi All,
A Good Subject.
I made mine many years ago for about $4, the cost of 2 mouse Pads.
Having A " Tough " Lathe it was made very easy, as there is a plate with 3 screws to hold the back Bearing in. Remove plate, turn a step piece to go over the Spindle, & big enough to take the end of a Vacuum Cleaner. Also needs 3 Holes to screw to where the plate came off.
You must open the V/Cleaner pipe vent, as it has to suck air, other wise you burn out the V/Cleaners Motor.
I had a much bigger hole in front to hold a Bowl or such. I used a home made Face Plate with a bit of 3/4in. thick Pine that I put a Shallow Hollow in, so as to get suction.
Worked fine as long as you kept the Speed down.
This was not my idea, & can't remember who thought of it.

hughie
19th January 2012, 08:44 AM
excellent stuff. :2tsup: I have a vac pump for several years and have as yet go further. Love the hairy oak, darn! I have got so many things to get off the ground :C

hughie
19th January 2012, 08:46 AM
You may need to be careful with the extra load placed on your bearings


A thought to consider, but not too serious I would have thought.

artme
19th January 2012, 09:12 AM
Good stuphph Neil!! :2tsup::2tsup::2tsup:

The point about the strength of the vacuum you pull is important. Saw afellow destroy a besutifull bowl like that.

Why not just use a vacuum cleaner? They provide plenty of suction.

Sawdust Maker
19th January 2012, 01:41 PM
Neil

great job, worth a greenie :2tsup:


Hey Neil

You may need to be careful with the extra load placed on your bearings.


Huon

Wouldn't an unturned hunk of wood be heavier then the nearly finished bowl and this setup :?

Interwood
19th January 2012, 03:33 PM
Hi Neil,

Great post.

Would you please post details of the Vacuum Pump please. (ie Capacity, Power, Pressure etc.)

I've decided to go the eBay route, and need to make sure that I'm going to buy one that will work.

Best regards, Chris


Below is a photo of my electric one, bought off a guy in Sydney ~$150, Ebay sells similar. The other air operated one is a simple (but good one) venturii pump, bought from an air specialist business in Brisbane (that went broke last year) ~$100.

The air one takes longer to draw a decent vacuum, so the electric is definitely better. At 's place a vacuum cleaner was used sucessfully, doesn't pull the same vacuum, but for the larger chucks it is fine. Definately need a decent vacuum for the 50mm one, as smaller area means less holding force.

Cheers

turnerted
19th January 2012, 04:34 PM
Neil
A good post
I have been using a vacuum chuck with a vacuum cleaner for some time now but having read this I may have to look into using a vacuum pump . My current setup definitly will not work when there is only a small contact area Also the howl of the vacuum cleaner is a bit trying.
One area I have found where caution is necessary is when using it to hold a natural edge burl bowl . These bowls can still be quite a bit out of balance when finished and I have had one launch itself off the vacuum chuck . Maybe the increased vacuum of a vacuum pump would solve this.

Ted

dai sensei
19th January 2012, 09:49 PM
Hey Neil

You may need to be careful with the extra load placed on your bearings.

What extra load on the bearings? The vacuum pulls the piece onto the chuck, so same load as any other chuck isn't it?


Would you please post details of the Vacuum Pump please. (ie Capacity, Power, Pressure etc.)

The electric one is a 4.2 cfm one and pulls almost full vacuum (I am sea level +50m max), great for stabilizing, but I will need to be careful on dainty stuff. I have a valve on the line to reduce vacuum if needed. It plugs straight into a std powerpoint.

The air one pulls slightly less vacuum, not much, but also takes 2mins to get there at its working pressure of 80psi air pressure.


Neil
A good post
I have been using a vacuum chuck with a vacuum cleaner for some time now but having read this I may have to look into using a vacuum pump . My current setup definitly will not work when there is only a small contact area Also the howl of the vacuum cleaner is a bit trying.
One area I have found where caution is necessary is when using it to hold a natural edge burl bowl . These bowls can still be quite a bit out of balance when finished and I have had one launch itself off the vacuum chuck . Maybe the increased vacuum of a vacuum pump would solve this.

Ted

Yes, a vacuum cleaner does work, but not for a 50mm head. This is what I need for the trinket boxes and the natural edge form I am making. Sticks well with the electric vacuum, but I still need to be very careful, still not much force holding it there. I will still use the tailstock as long as possible. Balance was not a problem, but bigger ones might pose a problem of out of balance.


Thanks for the comments

turnerted
10th March 2012, 04:39 PM
Neil
Are you using any type of filter in the vacuum line to prevent dust contamination of the oil in your pump ?One reference I found suggests this is an issue.
Also what type of shop sells all those brass(?) fittings you used to connect everything together?
Thanks
Ted

dai sensei
10th March 2012, 06:22 PM
Hmm, hadn't thought of the dust, but shouldn't be much as I will be gripping only finished pieces to remove tennon etc.

I get the fittings from a hydraulic hose and fittings supplier, like Enzed, check your yellow pages should be one near you.

Cheers

turnerted
11th March 2012, 11:34 AM
Thanks Neil
Ted

nalmo
13th March 2012, 10:44 PM
You might get some dust sucked in through the bleeder valve if you use the vacuum chuck while sanding.

dai sensei
13th March 2012, 11:15 PM
Bleeder valve will be shut though whilst gripping the piece, but yes I will need to ensure no dust around as I release it.

chuck1
17th March 2012, 12:55 PM
nice a new project when i get time!!!

turnerted
17th March 2012, 04:04 PM
Neil
I have noticed that after sanding the foot of burl bowls in particular, using my vacuum cleaner system,that I often have dust on the inside of the bowl at the finish . It is obviously getting through the fine cracks . I have seen a reference to making a filter to protect the pump from a length of PVC pipe with endcaps fitted and filled with aquarium filter material . Connectors are tapped into either end.
Ted

dai sensei
17th March 2012, 09:54 PM
I guess I can set up some aircon filter stuff I have in the line easy enough.

TTIT
18th March 2012, 03:19 PM
I guess I can set up some aircon filter stuff I have in the line easy enough.Maybe a inline air filter like I've used?!?!? Got it off eBay for bugger all. Only had to glue the tyre-valve into an open position to get it working - can't actually see the dust build up the way I've installed it but it's nice to know the pump is protected :shrug: . . . and I will take it off and clean it out . . . one day:B . . . . or maybe just turn it around :shrug:

turnerted
18th March 2012, 04:31 PM
The little air filter like TTIT has looks like the go . I thought about this but wondered if it would collapse under vavuum. Obviously not. E-bay has them for less than $13.
Ted

keltrader
3rd April 2012, 08:15 AM
Keen to get a vacuum pump. Checked out eBay but over $300. Can anyone recommend alternatives. Is there one for sale anywhere.

Fredo
3rd April 2012, 09:05 AM
keltrader - Just had a look on ebay, seems to be lot's from $100 up. Take a look at this link.
refrigeration vacuum pump | eBay (http://www.ebay.com.au/sch/i.html?_from=R40&_trksid=p3907.m570.l1311&_nkw=refrigeration+vacuum+pump&_sacat=See-All-Categories)

Fredo :U

keltrader
5th April 2012, 11:22 AM
Thanks Fredo. Could be the go.

smiife
10th April 2012, 08:14 PM
hi guys,
just thought i would add my 2 bobs worth,i have my vac chuck hooked up to my air compressor thru a box of valves i got from usa,i think it was about $200,put the chuck on the lathe hook up air line and go:2tsup:
cheers smiife:2tsup:

dai sensei
10th April 2012, 08:51 PM
I bought a compressed air filter with a 40 Micron Element from Ebay for ~$14 delivered and connected it up. Then after turning the base off my first project I noticed a few fine sawdust fibres in the bowl, so lucky I did, thanks for the heads up guys :2tsup:

Another problem has come up though. After turning up the base I took the piece off only to find a big black ring from probably minor slipping :~

They sanded out Ok, but has anyone else had the problem?

Is there a simple solution?

TTIT
10th April 2012, 11:13 PM
Haven't had that problem yet Neil but I suspect it would be due to the type of rubber you used for the seal. I used EVA foam for the 2 of my three chucks that I use most and the 3rd one has a rubber seal from an old vacuum cleaner which is very similar to EVA foam :shrug: - no problems yet - touch wood!!!

dai sensei
11th April 2012, 10:26 PM
Could well be the rubber I used, it couldn't be those catches I have. Do you use a clear colour, or any colour you can get?

Gawdelpus has suggested putting some baking paper over the rubber too, certainly worth a try, but replacing the rubber is easy too.

TTIT
11th April 2012, 11:29 PM
Could well be the rubber I used, it couldn't be those catches I have. Do you use a clear colour, or any colour you can get?................The only colour Clarke Rubber had in the 3mm stuff was black but it doesn't leave a mark :shrug:

hughie
12th April 2012, 09:57 AM
What ever seal you use as long as its closed cell foam leaking wont be an issue. As for dust and foreign bodies being sucked into the vac pump. The simplest way I am aware of the to fit a small container say .5 to 1L in the line before the pump. So it can act as a settling point, much like your cyclone dust extractor. Most Pneumatic suppliers will have one as this is a standard method of particle removal. Much better than a filter as it can be cleaned more readily with a quick washout.