High Speed Steel Grinding Jig.

[ieezitin]

Hello guys.
I posted a little while ago asking for tips and ideas on HSS lathe tooling grinding jigs and stuff, the feed back was great and there is a lot of pre-made jigs and machines that will do the job great, so as I did not get my Obama stimulus package in the mail I cant afford pre-made machinery or fancy set ups ill whip up something in the shop.

Lathe tool grinding angles is not an exact science so a simple efficient jig should suffice for the task at hand.

These are my requirements for this build, X Y Z movement of jig,  simple to use, use up what trash I have laying around, its got to be safe,  grind down little bits of tool steel to extract everything out of what I have, also I made myself a boring bar that uses old taps so I want  use up all those little pieces of old taps etc.

If during the build you see something that could improve on what I am doing feel free to share your idea, I will incorporate it into the design.

So!. I will start it off here,

This is the grinder i will be Modifying




I found some 2-½ x 2-1/2x ¼ angle coupled with some ¼ x 2 stainless steel flat bar and an old Craftsman Cross Fence with angle graduations on it. This shot is just laying everything out to get me a visual.



I liked what I saw so to the welding booth I go to slap some metal on it.



This shot is the jig in the vice, I laid all the flat  bar out on the angle iron installed the cross fence and slipped .005 shims in-between the fence so when the steel curls and shrinks I still get the distance right so the fence slides freely.



Well that did not work!. The gap was tighter that a ducks A(&*^s in water, so a little elbow grease with a course file and emery cloth plus a beer I whipped her into shape.



This is it finished lapped, filed and sanded.



More to come in the future.   Anthony

[Rob.Wilson]

Hi Anthony

Looking good , very nice clean  welding     i like the use of the cross fence .

Regards Rob

[Bernd]

Anthony,

Rob beat me to it. Very nice bead of weld you laid there. Is it TIG or MIG? I've got a Miller 210 MIG, so was wondering.

Going to follow this one closely since I need to build/modify a grinder also.

Bernd

[ieezitin]

Rob, Bernd thanks for the nice comments.

Its TIG, I only tig in the shop as I do not like to grind and chip off slag in the shop with all the machinery around.

I am a pipe welder for my living so it’s a big part of my life, irony is I was a machinist trained back in England but never found it pays well here in the States, since welding was a part of my apprenticeship I made more money welding.

I own a farm here in Maryland so when I was choosing my choice of welder I went for the mobile unit it’s a Miller Bobcat 225Dplus 2 cylinder Duetch diesel. Great machine AC/DC puts out about 280Amps welding, generator is around 8KW. This unit backs up as a power generator when the power fails here which is often.

The nitwits I buy my gas from sent me this time Helium and when you tig with it it runs a little strange and you cant  get down to low amperage without some silly little things happen to you, when I run this bottle of gas out and I get Argon replaced I am going to do a thread on the basics of Tig & Stick welding, it really is easy as I will show.

More pictures tomorrow as I will be first thing in the morning getting back on my project..   All the best.      Anthony

[ieezitin]

Hello. I am back on it.

So!. In the picture below I took off the original tool rest angle bracket leaving just the flat bar. This bar is fixed at the bottom via a 3/8-16 piece of all thread and secured by a wing nut and a locking washer, it pivots on the fixture, so I shall utilize this as this will allow me to raise or lower ( Z axis ) the new jig at the same time as either drawing it closer or moving it away.



Now, I want my jig to rotate or swivel in the X axis and Y. So I rummaged around and came up with this little grab bag of stash!



Now by putting these two pieces of square washers on the support bar and having a bolt through them its going to give me a pivot point in the X axis,



So now in this picture you can see my full objective. My two square washers are the base for the Kendorf ( unistruct ) or slide rail ( that’s yellow colored piece of C-Channel ) the odd leg L-bracket sits on the slide rail which is affixed by a bolt through to a grab nut held in the slide rail this allows me travel in the X axis, the L-bracket has a hole on the vertical rise to which the angle iron jig will be bolted too giving me my Y axis movement.



So I slapped it all together, held it with a clamp and I played around awhile making sure it moves as I want it to. Don’t see any problems here so I will break out old sparkey and weld it together.



Here is the result of today’s work the bracket is welded. Tomorrow I am going to drill the hole through the angle jig.

Bye for now.    Anthony.

[ieezitin]

Ok!
I did not like the base of the cross slide and if you notice I left a gap on the base in the X direction, this was for to feed in the tool into the side of the wheel, I played with it and just did not like it. I put the thinking cap on and decided to install a stainless plate on the bottom. Here is the result.




Here is the view now with the cross fence base installed. Notice I made a long bolt with a stainless tube butting up to the angle bracket. I did this so when I want to rotate it in the Y axis its long enough just to comfortably grip and twist, I will make a nice handle for it later its working for me know.




So I did not like the cross fence the way it was, the side is plastic and when I was fiddling with it I noticed that the tool steel was scratching and tearing strips off it, so I got some aluminum plate and set about rebuilding the plastic part



As you now can see I beefed up the plastic part. It came out nice and the feel was better, another plus was that the tool steel slipped more smoothly, aluminum is quite a nice bearing surface when polished, I know it will ware quick but replacing it will not be a chore. Going back to feeding the tool bit into the side of the wheel I was playing with it and I noticed that my fingers would come quite close to the wheel if I were to shape small pieces. ! Uh huh! Cant have that so I have decided to make a jig on a jig, here you will see a gear from an old printer, 3/8 stainless all thread and two deep groove ball bearings, I am going to make a rack and pinion type feeder jig.



Itching to play with it a while I set up for a trial run. I am going to grind an end cutting edge of 20 deg at the same time grinding a 6 deg end relief. 




Here is the result of the first cut. It took from a blank to get both edges about 12 minuets or exactly one beer.  Im happy so far.

Any ideas I am all ears…….       Anthony.

[ieezitin]

Well.
Its been very cold here and my farm seems to be breaking down a lot which in turn needs fixing so progress on the jig slowed down a little.

But I had a few hours to spare so onward I dug in. I made the hold down plate as shown here, the all thread is ¼-20 and drilled straight through the aluminum plate. I turned up some large diameter brass disks and knurled them, the back pin has a disk with a raised hub to support the force applied from the front pin closest the cutting piece being clamped.



Both threaded rods have springs connected to the disks so both are pushing up, this is so that when I want to change the height of the cutter it raises easy and makes for a nice level lift. Works very well, nice smoother action. The clamp pressure is very tight and I am happy with it. This clamp will work from ¼ square up too 1 inch.



I was playing around with the Y axis and noticed the way I made the ways , it was sticky and was very annoying coupled with it was not true,  I tried to counter act this with putting bearings at key points to make things smoother. I just made things worse so I have decided to scrap the base. I am going to go to a metal supplier I use and see if he has some bearings to do this job. I have a lot of 7mm ground drill rod I salvage from discarded printers and I am looking for some ball-bushing type bearings.

I know I started out with a cheap and cheerful attitude to this build, but the more I tinker with this the more I realize I need something accurate, as my intentions are to grind threading tips and do finesse touch ups on dull tooling.


Any ideas I am all ears.               Anthony.

[tinkerer]

Anthony, you are a skilled fabricator and I have found this to be accurate and stable. I can take detailed pictures and measurements for you if needed, but the concept is pretty clear. The long one on the right side is for wood lathe chisels. The beauty of this is that you can take it form the rough wheel on the left to the fine wheel on the right and not have to check the set up. A small change to the rest will give you movement in all three axis's. If you need more info, just ask.

[ieezitin]

Tink.

What most I got from your set up is the fact you can go from the course wheel to fine.

I like that idea of not changing the angles and such for both wheels..

Your set up and measurements  will not help me but thank you for your willingness to furnish me with them. Your photos gave me ideas.

I am going to incorporate your idea of the wheel exchange. And the jig below each wheel.

Great!. Now you have added another 5 hours to the project. Appreciate your advice. 

All the best.             Anthony.

[tinkerer]

Glad to help Anthony. Another thought is, you can make several different setups, kind of like tool holders for the tool post, for different angles and just snap them on the rest and grind away. Hope that doesn't add to the time, but time spent now can save later. Maybe not.