Boring a bronze casting, actually on size.

[Abratool]

Hi Abratool, I'm pretty sure it's due to harmonics, I was getting a tone from the shafts once I switched to a harder wheel if I advanced the wheel into the shaft while the wheel was at one end of the shaft, so it was susceptible to vibration. I may experiment with damping the shafts next time to see how it goes...maybe a lead weight round the middle of the shaft.

Thanks Graziano, I will be interested in your findings.
There are certainly a lot of variables with grinding.
regards
Bruce

[Anorak Bob]

A neat arsenal of spindles you have there Mark. Beautiful execution.

BT

[Bryan]

These three I'm planning on mounting turret style on a pedestal with one motor so you can step on a foot pedal that releases the belt tension and allows the desired spindle to be brought up into position. I should be able to fit the whole lot into one corner of the shed and save a bit of space into the bargain. The spindles will have a buff, wire wheels, scotchbrite wheels, a green silicon carbide and a white aluminium cup wheel with drill sharpening jig.

That I would like to see. I hope you will post it Mark. I have a tool grinding setup in mind but much less interesting than that.

[Graziano]

Thanks Bob and Bryan, it's interesting to talk to people who ran manufacturing business's to see what they rate as the most important bits of equipment to begin with. Some of the gear that rated highly were a lathe, then a disc sander, a bandsaw, an assortment of spindles with various wheels then maybe a horizontal bandsaw. I was told I can never have enough spindles, get to work on some more!.

Bryan: I have a 100x 50mm column welded to a 350mm steel circle (hole cutout) my plan is to have a 1-2 Hp motor mounted on the rear of the column on a slide so it slides up and down for belt tension, a foot operated lever will lift it up and gravity/springs will let it slide down. round the front of the lever will be a vertical bar that goes down with the depressed lever and releases the spindles mounted on a Y shaped turret made from steel channel. The turret is angled at 45 degrees so that the unused spindles go vertical while the spindle in use goes horizontal at the front ready for use. The only hassle is getting the belts off and on, I may let each spindle have it's own set of belts.

The best way to describe the "Turret" would be three spindles bolted to a section of C channel with the flat web facing up. Each end of the channel is cut at 45 degrees then welded to a thick steel disc about 150mm diameter. The three spindles are 120 degrees evenly spaced around the disc. Now for the good bit: if you tip the turret disc 45 degrees, each spindle goes vertical on it's channel as the disc rotates, then goes horizontal for use.....hmmm time for a drawing I think.

[franco]

Hi Ueeee, I have a bar that has the spot for the number one chuck jaw marked carefully and the bar was machined between the chuck and the tailstock then polished a bit with wet and dry. The bar can theoretically be eccentric a bit and still bore true so long as the bar is parallel to the lathe ways.....I think. The lathe is just an old 1960's Advance lathe I fixed up and trued up a bit, still has some way wear though.

RC's link: lathefan - YouTube

Graziano,

The bar does not even have to be parallel to the lathe ways - in fact mounting the bar on a centre held in a boring head at one end provides an easy way of applying small, accurate tool adjustments for finishing cuts. See:
https://www.woodworkforums.com/f65/us...ng-bar-129635/
posts 4 to 14, and post 24 for the explanation.

Frank.

[Graziano]

This is pretty much what I'm planning, hopefully the drawing adds some info rather than confusing things. Thanks Frank, I'll read and digest the posts a bit.

[Abratool]

This is pretty much what I'm planning, hopefully the drawing adds some info rather than confusing things. Thanks Frank, I'll read and digest the posts a bit.

A great idea, very practical & useful.
Lots of spindles set up with various wheels Scotchbrite etc simplify things.
regards
Bruce

[Anorak Bob]

I like it Mark.

If the spindle support arms were horizontal rather than inclined, balance might not be an issue. With the inclined set up, wouldn't there be a possibility for the heaviest spindle wanting to swing around into the lowest position? What are you planning to use to position and lock the arms? Some sort of detent?

Bob.

[Graziano]

I like it Mark.

If the spindle support arms were horizontal rather than inclined, balance might not be an issue. With the inclined set up, wouldn't there be a possibility for the heaviest spindle wanting to swing around into the lowest position? What are you planning to use to position and lock the arms? Some sort of detent?

Bob.

Hi Bob, I didn't notice earlier but I'm learning a lot of plural terms for items, according to Greg we have a "Bagatelle" of Waldown drill presses, bagatelle is apparently a narrow table that an early version of billiards was played on so it actually does describe the narrow iron table. Then we have your term, an "arsenal" of spindles which I kind of like.

As far as the tables go I was thinking of using a Holden stub axle for the inclined turret which should allow me to have a tight rigid setup that will take a bit of force to rotate. for locking the turret position I hadn't gone much past the idea of a kind of fat taper pin going into a reamed hole so that it's fairly tight and maybe locking it with an over centre pivot or a stiff coil spring.

[RayG]

Hi Graziano,

Having the axis tilted like that rather than horizontal, means it will use less floor space...

Looks like pretty nifty idea.. maybe add a tray or pot on the side to keep coolant handy?

Regards
Ray

[Graziano]

Hi Graziano,

Having the axis tilted like that rather than horizontal, means it will use less floor space...

Looks like pretty nifty idea.. maybe add a tray or pot on the side to keep coolant handy?

Regards
Ray

Hi Ray, There was someone on Practical machinist who had a kind of fixed version, that you had to approach from all directions to use the attached bench grinders, I thought I could come up with something a bit more compact that you could use from the one spot. I like the idea of a tray/shelf for accessories, I'll have to attach it to the stub axle somehow, maybe tapping and drilling the shaft, or two nuts locking onto the flat metal sheet.

Cheers,
Mark