Thread: Tool sharpening attachment for DIY tangential

Finished the tool grinding attachment today. Just needs a coat of paint - maybe tomorrow. The table tilts back and forth, twists left and right and is also adjustable up and down. There is also an adjustment for reach that also twists side to side. Made from scraps I had lying around in the shed: heavy walled 7/8" tube and reamed out gas pipe welded to the grinder stand. The jig itself is just two bits of 3mm plate screwed to a small 6mm guide plate. Not a tool and cutter grinder I know, but it suits my needs. Poor man equipment!

Looks good th62. Any ideas yet to grind the angles for threading bits?

I need to make up a new system for my grinders including the new Abbot and Ashby. I may use your idea but with square tubing if I can find enough that fits. I used a lot recently for a SCMS stand. Adjustable supports etc. Still need to make more of these supports and a stop.

I have two bits of 5mm brass flat lengthways along the grinder rest plate and another bit attached to the bottom of another aluminium plate which slides between the first two like a set of ways. An adjustable angle fence and a device to hold my point diamond, and allow movement in and out so I can precisely dress the wheel dead parallel to the ways.

I have started making a more complex unit with adjustable ways for even more precise control. Uses the same brass strip material. I have a large peice of 5mm brass. About 500mm X 400mm.

It would be interesting to see what setups others have made.

Dean

I found my original table was a little fiddly to use so I extended the table and added a 10mm slot across the middle to hold and guide the jig. I also made a new jig for grinding threading bits: loosening the front allen head and extending the top section all the way to the stop sets it at 55 degrees, the middle position sets it at 60. I did make a small finger clamp to hold the tool bit in place but I found it works better without it so it was discarded. Also finished off the round bit holder and made a new threading bit holder. The threading bit holder is offset to the left so it will take a full length bit and also clear the tool post. There is no back rake on the holder and the side rake is ground by hand/eye. I haven’t had a lot of success there, so I may have to make another jig for that.

Hi TH62
Nice work on your stand, The great Jack Nicklaus called "putting" the other game but for a novice like myself "tool bit grinding" is the other game in metalwork. I was given the POS grinder and made this table [3 way adjustable] to put it to work, I only use HSS bits because my with my old Qualos Junior lathe you measure the backlash in 1/8's not thou's and do not want to ruin carbide bits with all the chatter the lathe puts out.
I need to make more holders like you have, although as it is the tooling does stay sharper for longer than hand grinding, I have just put the green stone on and need to reset the table and will buy a new fine grey stone wheel next trip to H&F.

Regards
Paul

Sounds like an excellent project: restoring the Qualos!

I should but I have a Rexman in a 100 bits already.

Originally Posted by whitey56

I should but I have a Rexman in a 100 bits already.

One at a time is a good plan. I have started putting projects into seperate white buckets (from work) so I can write what the project is and then when I find this plie of bits down the track I will know what they are. I have several piles of plate steel cut up. I know one is to convert a hydraulic jack to lift machinery but I don't remember what the other one is, nor which is which LOL. These are only small projects tho.

Dean

Originally Posted by th62

I found my original table was a little fiddly to use so I extended the table and added a 10mm slot across the middle to hold and guide the jig. I also made a new jig for grinding threading bits: loosening the front allen head and extending the top section all the way to the stop sets it at 55 degrees, the middle position sets it at 60. I did make a small finger clamp to hold the tool bit in place but I found it works better without it so it was discarded. Also finished off the round bit holder and made a new threading bit holder. The threading bit holder is offset to the left so it will take a full length bit and also clear the tool post. There is no back rake on the holder and the side rake is ground by hand/eye. I haven’t had a lot of success there, so I may have to make another jig for that.

I was thinking a little bit different with the thread cutting tool. The "Diamond Tool Holder" from Eccentric Eng. uses the same holder but with the sides of the HSS ground at an angle. Their jig has a slot to lay the HSS lengthways along it and a screrw to lift the jig up to the right angle. This angle has to be determined by trial and error according to them but I think it may be calculated. It is a combination of the two angles. Their website will explain it better I think.

Dean

I tried out my thread cutting holder today - no good: The tool needs to be clamped from the top, too much movement otherwise. I might try regrinding the angles on the tangential and try threading with that. The finish I've been getting on this lathe is excellent, particularly with the tangential holder, but I haven't been able to cut a decent thread yet, the finish is abysmal.