Author Topic: Basic Tool Sharpening Jig  (Read 762 times)

Offline propforward

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Basic Tool Sharpening Jig
« on: October 14, 2018, 10:08:06 PM »
I recently learned that my free hand ground cutting tools are simply not good enough. I found myself having a terrible time turning mild steel, which shouldn't be that hard, surely? After a lot of regrinding, I did satisfy myself that a lot of the problems I was having were from the quality of the cutting tools I had ground.

I've been meaning to make Harold Halls basic tool grinding table for ages, so I finally got going on it.

I made a few changes to the design - nothing extraordinary, but I don't want to have to get on the thing with a bunch of hand tools to set it up each time, so it's going to be held steady with a magnetic base (10 dollars from Grizzly), and changing out a few of the screws for hand knobs.

Looks sort of like this, although the model isn't quite finished.



I beefed up some parts as well.

This is likely a little more complicated than it really needs to be, but it does mean that it can be set precisely, and furthermore gives me a lot of practice at various techniques, such as turning threads, slotting, milling to size, angled cuts on the mill, positioning holes.......all good general purpose stuff.

First few parts - some purchased, some made. Mixed results on my first set of threads. Like I say - having some difficulties with mild steel at the moment, but making progress. I ended up having to run a die down my first turned threads because they were rough. But at least the diameters and pitches were correct.



I'm making the table out of 5/16" steel, rather than 6mm, just for a bit of extra material for the tapped holes.

I started out by spotting all the hole positions - positioned using the hand wheel dials. I counted to ten a lot today.



Then blind drilled



For the slot, needed to guide a block on a leadscrew, I drilled 1/4" holes at each end of the slot, and then milled the slot to size using a 3/16" end mill, rather than just try and mill the slot with a 1/4" end mill. I figured this would give me better control over the slot width, by milling one side, then the other. It worked - I was less than 0.001" off on the width. Somewhat pleased about that.





I did the slot in 3 passes, taking the slot down about 1/8" each time. Although it really didn't strain anything, so I could possibly have done this in 2 passes.





Finished article, before deburring and tapping



Next up - some bearing blocks, to hold the various leadscrews. Pretty simple - 1" long brass blocks, with holes to attach to the table, and a cross hole to hold the leadscrews.

I was lamenting not having a work stop yet, since I have to make 3 of these, then realised I do in fact have a simple one, which came with my vise, so these were knocked out in short order.









I actually put the table back in the mill, and put a chamfer on the slot with a countersink tool, to clean it up. Then after deburring everything, put these few parts together.





Pleased to see that all my holes lined up so far - all done by positioning with hand wheels, so while my machined finishes aren't perfect yet, I can at least count, so that must amount to something.

Next up, the sliding block and lead screw, and fence. That will be for next weekend though, too much happening this week - won't get in the shop for a bit.
« Last Edit: October 14, 2018, 10:12:34 PM by propforward »
Stuart

Offline Kim

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Re: Basic Tool Sharpening Jig
« Reply #1 on: October 15, 2018, 05:44:18 AM »
Looks like a good start on a great tool!
l'll be interested to see how your modifications work out.   Seems like they will be a real help!
Kim

Offline Ye-Ole Steam Dude

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Re: Basic Tool Sharpening Jig
« Reply #2 on: October 15, 2018, 09:54:15 AM »
Hello Stuart,

I am also interested and will be following your progress.

Have a great day,
Thomas