Minilathe Tooling Set

[Howard LewisParticipant @howardlewis46836]

Coming in late, AS USUAL!

A RIGHT HAND tools points tom the left when you view it from the operator's position, (i e points towards the Headstock on YOUR left. Vice Versa for a LEFT HAND tool, pointing towards the Tailstock, on YOUR RIGHT.

The tool edges do need to be ground. The point of the tool must be on the centreline of the lathe.

Too high causes the tool to rub.

Too low means that the tool does not contact the work at the correect angle, and apparently has excessive clearance.

The sharp edge exerts high pressure on the workpiece, (large force acting on small area) and so cuts the metal. The relief angles prevent the tool from rubbing, and help swarf to escape.

Tangential tools cut extremely well, and produce a good finish with a fine feed, even without a small radius on the nose. They are easy to set to centre height. Most people with Tangential tools seem to use almost nothing else for facing and external turning, whether taking a deep or a shallow cut.

Being HSS toolbits, they can be ground using an ordinary grey carborundum wheel. Green or diamond wheels are needed to grind Carbide tools.

Carbide tools benefit from high speeds, which produce the heat to soften the workpiece and cut it in a very localised and minute area. (Replaceable tips are, often, relatively blunt; a sharp edge would very soon break,and the rubbing produces the heat need to cut the metal.)

There are lots of folk on here who can explain all this far better than I can.

Howard

[Ron LadenParticipant @ronladen17547]

Thanks for all the advice guys.

I have ordered a HSS set from ArcEuro as per the picture Jon posted at the start of the thread. I,m hoping I will pick up the tool grinding ok, I am ok at sharpening drill bits free hand. I was taught by an old engineer many moons ago and it stuck with me.

Having looked at them again I dont think the carbide set have been sharpened, ground to shape yes, but sharpened no. I dont have a green wheel so they will have to wait before I give them a try.

Thanks again guys

Ron

[Alan VosParticipant @alanvos39612]

Posted by Neil Wyatt on 19/06/2018 14:55:35:

A significant proportion of cheap brazed tooling isn't finish ground.

This is the bit I don't understand. Some years ago I bough a mini lathe with the customary 'free' set of brazed tooling. I knew enough to know they were not working very well. Both my own (beginner) hand ground HSS and insert tooling worked much better. It never occured to me that anybody would ship unfinshed tools in a 'beginners' package. Why do they do that? A set of finished HSS would make more sense.

[Ron LadenParticipant @ronladen17547]

I also dont know why Alan but I,m guessing cost. When I ordered the lathe I was considering the full package deal where you get the lathe and a host of accessories. However I decided against it and phoned asking for the best price for the lathe a set of cutting tools and a tailstock chuck and I got a really good deal.

I didnt think about the type of tools I would receive but obviously assumed it would be a working set ready to go. The supplier does a HSS set for about £45 and the brazed set I was sent is just over £20 so you can see how that came about as part of the deal.

Your right though Alan whats the point of sending out tooling that needs finishing when many of the mini lathes will be going out to beginners.

Ron

 

Edited By Ron Laden on 19/06/2018 19:49:45

[Ron LadenParticipant @ronladen17547]

Well one bit of good news re the carbide set, my engineering manager friend said he will take them to his work and get one of the turners to put an edge on them all for me. I have the HSS set on the way but it will be good to compare the two types once I have them.

Ron

[Ian S CParticipant @iansc]

It is a good idea to get a diamond lap these in one form are a plastic strip about 20 mm wide x 100 mm long, and 4 mm thick with a pad about 20 mm x 40 mm containing the diamond lapping area, they can be got in 3 grades, fine, med, coarse. You can even get them in garden shops.

Ian S C

[Ron LadenParticipant @ronladen17547]

Thanks Ian, do you need all 3, the coarse, medium and fine..?  

Ron

 

Edited By Ron Laden on 20/06/2018 11:10:52

[Jon GibbsParticipant @jongibbs59756]

I would just buy medium and fine unless they come as a set of 3.

My experience is that they all eventually become "very fine" after a while but that might be the repeated use and "tongue-oil" lubrication I use

HTH

Jon

[SillyOldDufferModerator @sillyoldduffer]

Posted by Ron Laden on 20/06/2018 10:18:03:

Well one bit of good news re the carbide set, my engineering manager friend said he will take them to his work and get one of the turners to put an edge on them all for me. I have the HSS set on the way but it will be good to compare the two types once I have them.

Ron

When offering advice I'll try to remember that you can already sharpen twist drills by hand and have access to some professional support! That's a really good start in this hobby. Many newbies launch on their own and learn by making lots of mistakes. Not difficult to guess how I know that…

Dave

[Ron LadenParticipant @ronladen17547]

Thanks Jon, I will organise getting them.

Dave, I have quite a few friends who can offer support but to be honest I try to use them as little as possible, not that I,m ungrateful its just wanting to do as much myself as possible. I dont have a green wheel for the grinder so the offer of a skilled turner to sharpen the carbide set was too good to turn down. Mistakes….well I make plenty of those, lucky is the man that doesnt make any, though in reality I doubt that there are many of them about.

Edited By Ron Laden on 20/06/2018 16:58:34

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