Protractor base for grinder mounted on cross-slide

[Brian Rupnow]

I have ordered a toolpost grinder from Little Machine Shop that doesn't really mount to the toolpost. It mounts to the cross-slide. Somewhere in all of my searching for toolpost grinders I seen where someone had mounted a protractor base which sets between the cross-slide and the grinder so the grinder could be set at any desired angle. Of course now I can't find it. Does anybody have a link to that?---Brian

[crueby]

This guy shows one he made, halfway down the page, looks easy to do.
https://www.micro-machine-shop.com/tool_post_grinder.htm

[Brian Rupnow]

Thank you Chris---That's the one I was looking for.---Brian

[Brian Rupnow]

I am rapidly losing faith about getting a small heat treat oven, however my toolpost grinder (which doesn't actually fit on a toolpost, but instead bolts to the cross slide) just arrived as I was posting this. I have created a 3D model of my lathe, and will also create a model of the grinder, and then see what is involved with making a new, very shallow topslide that can fit between the grinder and the cross-slide so that the grinder can also be "set over" to grind a taper.

[Brian Rupnow]

Here we have a 3D model of my lathe with a 3D model of the new grinder from Little Machine Shop. There is about 1 1/4" vertical clearance between the underside of the grinder base and the top of my cross slide when the center of the lathe chuck is horizontal with the centerline of the grinder.

[Brian Rupnow]

It appears that I could make a new protractor topslide that would allow me to grind a taper with the toolpost grinder from Little Machine Shop. It wouldn't be easy, but it's doable. It would require making at least 3 new major pieces and cantilevering most of the grinder out towards the headstock side of the cross-slide, but it would allow me to grind at least 2 1/2" of taper. Remember, my DRO for my Y axis is attached to the headstock side of the cross-slide, and I have to get out far enough to clear it.

[crueby]

Basic question - what is the use for the grinder? What does it do that you cant do with normal turning? 

[Brian Rupnow]

It can machine really hard stuff that an ordinary carbide wouldn't touch. It can take very minimal cuts, like .0005" and leave a very clean ground finish.

[Brian Rupnow]

These parts aren't terribly complex to machine. I've never machined a dovetail before. I could certainly buy a dovetail cutting tool and teach myself how to use it. I haven't included the gib strip , endplate, nor adjusting handle here, but they are all simple shapes. This is just a "what if" exercise for now. Right now if I use the new toolpost grinder in my compression ring making exercise, it can just bolt squarely to the grey cross-slide.

[pgp001]

Brian

Re your heat treat oven............
I have just got this one sorted out, it is the type normally used for enamel, but works very well on heat treatment. They can be had on ebay for not a lot of money, I managed to get this one for £50 and the rest of the bits probably cost around another £30 including switches and indicator lamps etc.

I bought a very cheap electronic controller and relay kit, it was very simple to wire up and just needed a hole adding in the door for the thermocouple.





Phil

[Brian Rupnow]

Now that I have designed a way in which the Little Machine Shop Toolpost Grinder can be mounted to my lathe so that that it can be used to turn tapers, it's time to get back to reality. The reality is that I don't really need this ability to turn tapers right now, even if it is a nice design exercise. I only need the toolpost grinder to travel in the X or Y axis. To do this I only need one adapter plate, and the nice thing is that I don't even have to remove my topslide or quick change toolpost to do it. The adapter is made from 1 1/4" thick aluminum plate which picks up the bolt pattern of the grinder and the two keyed slots in my current cross-slide.

[Brian Rupnow]

A good days work, well done!! The toolpost grinder is attached to an approximate 1 3/16" thick aluminum plate. The aluminum plate has four bolts that go through zero clearance holes in the plate and through the topslide  to two long custom crafted tee nuts. I am very fortunate to have tee slots in my cross slide.  That piece of round bar in the lathe chuck is 1 1/4" diameter. ---The nice part of all this is that I don't even have to remove my topslide and quick change toolpost!!!

[Don1966]

I convert that same grinder to a tool post drill. I made a new shaft for the Chuck and can convert back any time I need to grind.

 
Don

[Brian Rupnow]

Hi Don---I don't understand your post. Do you mean that you put a drill on the grinder shaft and drill holes with it? That seems awful fast for me but I've probably misunderstood what you meant.----Brian

[Don1966]

Hi Don---I don't understand your post. Do you mean that you put a drill on the grinder shaft and drill holes with it? That seems awful fast for me but I've probably misunderstood what you meant.----Brian

I replaced the shaft and fitted a drill Chuck and made a tool post drill out of it. I also have a variable speed foot switch I used to control the speed the motor is a universal motor it can run on AC or DC and a control like a light dimmer. My foot switch is variable AC. For brass and aluminum it’s not necessary, but hard steel it will burn the bit. I have drilled soft steel also at that speed. All the hole plates on my versatile dividing head (VDH) were drilled with it at high speed. It made short work of the holes.

Regards Don