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Grahame Collins
3rd Oct 2006, 10:30 PM
Evening All,
I have been buggerising around trying to hold small fiddlybit things to weld in certain fixed postions.I have been looking around in frustartion for a better way of holding things. Down the track I have some aluminium props to weld.

I saw a pic in the the Aust Wood Review where the same principle is used for an adjustable wood carvers vice. I had what some unkind souls that know me call - A rush of s--t to the brain.

The result is what you see below. There's no plans,but it consists of

A tow ball with the shoulder flange turned off on the lathe. A 12mm Joiner nut welded to this.

A 75 x 40 channel section -with a step cutout, for the bench thickness and plate welded to it -drilled hole in ittapped to 12mm and threaded with cyclone rod thread and 6mm welded tee handle across a Cyclone rod Joiner nut.
2 Oxy cut steel rings 80 OD x 40 ID x 8mm th--cut bevel inside the id with the lathe
Various bits 12mm diameter cyclone rod
8mm flat bar
There is a fitting to hold the aluminium propellors ( not pictured )
There is a face plate to complete.
Thought the carver blokes may be interested.


Cheers
Grahame

Andy Mac
3rd Oct 2006, 11:48 PM
Nice work Grahame, it should work well. Any thought on putting a handle on the lock bolt/s instead of using a spanner?

Cheers,

Grahame Collins
4th Oct 2006, 12:36 AM
The bolts are socket head bolts and do up with an allen key.
I purposely avoided a weld on handle because I could not remove the top ring if I need to cos I could nor get rotation to remove that bolt.

I can get all three bolts set up to a point where it only takes 1/4 of a single bolt turn to get full lock up.
I forgot to mention the flat bar visible at the base.It is a dogleg handle tacked to a nut. It allows rotation of the channel frame to orient the slot in the top ring. Once again about 1/4 turn and it locks up.

The unit looks crap at the moment and photographs worse than it actually looks., even though it I dressed the parts on a linisher.
I have to paint it.I'll pull it apart and take more piccies at the same time if there is further interest

Cheers
Grahame.

Metal Head
4th Oct 2006, 02:29 PM
Hi Grahame,

Nice design - my wife would wish I had "A rush of s--t to the brain" more often:D.

What type of welding are you going to use when you do the aluminium props?. It would be great if you could put some photo's up when you get around to doing that;).

Regards
David

Grahame Collins
4th Oct 2006, 02:58 PM
Gidday Metalhead

Tig is the suitable welding process for props.
I hope to get some trashed props from some local marine dealers to practice on, before I attempt one for a friend.

Don,t dispair. All these sorts of ideas are not usually truly original.

The ideas are often a synthesis of use a completely different activity. Like many other things are borne out of need. I needed the props ( and other welded bits and pieces ) to be precisely positioned and bloody well stay rock steady when the arc is struck.
I am sure you will be ready with applicable ideas when the time is right.
cheers
Grahame

NewLou
18th Oct 2007, 10:42 AM
Hey Grahame:)

What a fantastic idea! Anychance of an update on how shes held up and some recent piccies! (Any limitations u've noted or has she exceeded your expectations!)

I'd love some plans to knock up one myself! Looks really handy!!!!

REgards LOu:2tsup:

Grahame Collins
18th Oct 2007, 06:14 PM
Hi Lou,

It is a handy gizmo if I have a relatively small weldment to work on.
I can position it by nipping up one of the bolts, to set at height and angle and rotate by hand,as required.

The versatility is putting the thread on the shank of the towball allowing all manner of attachments/fittings.

It is limited to items that are relatively small in size and weight. Later on I'll look at a motor driven rotator as work demands.
No pics for the moment,camera is on the frittz,will work on it.

At the moment can only do a hand sketch and I'll scan and send it it on the weekend.

Grahame :cool:

Ticky
18th Oct 2007, 09:55 PM
Nice one Graham, I like it alot.

Might not be a bad idea to give the ball & the lock down bolts a coat of grease. I realize this would be more of an issue with Mig or Arc, but better safe than sorry.

Steve

Grahame Collins
18th Oct 2007, 10:23 PM
Steve
Thanks for the compliment.

The fit between the ball and rings precludes any arcing if the threads are done up snug. Maybe there might be an arc if they were dead loose but they are never left that way.
If you are worried about it, an auxiliary earth strap can be fitted directly to top mounting plate or fixture,to prevent that.

The plate attached to the shank thread is of a 150mm diameter that shields spatter getting into the ball and ring fit.

The thing locks up on just half a turn of the bolt. I use allen key socket cap heads. I thought about using a handle but its length would prevent unthreading that bolt, if disassembly was required.

cheers
Grahame

Ticky
18th Oct 2007, 10:38 PM
The fit between the ball and rings precludes any arcing if the threads are done up snug. Maybe there might be an arc if they were dead loose but they are never left that way.
If you are worried about it, an auxiliary earth strap can be fitted directly to top mounting plate or fixture,to prevent that.

The plate attached to the shank thread is of a 150mm diameter that shields spatter getting into the ball and ring fit.

The thing locks up on just half a turn of the bolt. I use allen key socket cap heads. I thought about using a handle but its length would prevent unthreading that bolt, if disassembly was required.

cheers
Grahame


Graham,

I was not worried abot arcing, I can tell from your pic that you have that problem well & truly covered. It was the spatter aspect that I was MILDLY concerned abot, as I said, not as much of a problem with Tig as it could be with Mig or Arc. Also not a huge problem if welding Ally or even Brazing, but this jig will get used for all sorts of jobs & you know how rods & even 4" of wire from something falling againt the trigger, will always arc against the wrong thing.

Steve

Fossil
19th Oct 2007, 03:04 PM
Hmmmm.... I must be going senile. I can't work out how the fixture works. :-

I'll have another look after a few beers tonight, and I am sure all will become clearer.

Great work anyway graham. :)

Grahame Collins
19th Oct 2007, 06:37 PM
G,day Fossil,

Its basically two solid steel rings that encircle the ball body above and below its equator.The allows a clamping action between the two plates when the bolt is tightened.

The bottom ring is fixed -welded- attached to the bench clamp or just to an arm which is welded to the bench.This ring is drilled and tapped 3 places 120 degrees apart for M6 thread.

The top ring floats free and is pulled down to the upper surface. This upper ring needs to be match drilled with the lower ring and those upper ring holes opened out for clearance of the bolts.

The big holes can be chamfered to match the ball curvature giving more contact surface area and therefore a better grip when the lock up is applied.

The upper ring has a gap cut into it to allow the ball shank to drop to the horizontal position. In essence, the tighten loosen sequence is controlled by 1 screw only,the other two provide a leverage and position function.

I did not opt for a fixed handle on one of the bolts because it prevents disassembly if needed.An allen key, permanently left in position does the job

A lathe with a chuck opening capable of 50mm is needed to machine the flange off the ball as well as dress and chamfer the two rings.

Ring OD is about 75mm ,ID 45mm which suits the 50mm diameter. I welded a 12mm cyclone rod joiner nut on top of the shank of the ball. Attachments can be then fitted with 12mm thread.

I hope this helps explain it better.

Grahame

Grahame Collins
19th Oct 2007, 06:54 PM
And there's more

Here's another slightly different approach.

The ball is enclosed in a close fitting pipe and a blank with a threaded hole tacked into the end. The mounting arm is attached to the side of the pipe.

I have not done anything with this one as the other works well.
i mention it because I made it out of bits and pieces laying around and it may be easier to make.


Grahame

Fossil
20th Oct 2007, 10:09 AM
Ah Ha!

I am a goose. I was looking at it as though the ball section clamped down on the work! When you were talking about an alloy prop, I assumed you meant ACRO prop, not boat prop, so that got me a little confused. I better get me some omega-3 :rolleyes:

Thanks for the explanation though. I might make one myself when I get through some of the almost finished projects on the go right now.