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View Full Version : WIP Sharpening Jig from H Hall Milling Book



steamingbill
4th Sep 2016, 06:01 PM
Hello,

Am almost finished this sharpening jig and looking forward to having a go at sharpening drills and end mills. An added bonus will be easier to grind 40, 55, 60, 29 etc etc degree tips.

Not much to discuss that isnt adequately covered by Harold Hall on his website or in his book see both here Grind Rest, Advanced (http://www.homews.co.uk/page145.html). He also designed a QCTP that I didnt know about and it looks interesting, see the web page.

Am quite chuffed as I felt that this might be too difficult for me - I did have to make a couple of pieces twice.

Learnings :

When cutting the slots I learned that I need to tighten the gibs

Succesfully used tungsten carbide router bits to make the aluminium dovetails and blocks. Got a good finish on the aluminium.

Am not good at fine finishing cuts with HSS mill bit on mild steel - will make a flycutter and see if that gives me a better finish, although sharper bits make a big difference. Will try facemill with only 1 tooth and see if that is a substitute for a flycutter.

Am not good at cutting square blocks on mill - my dovetail stack was 0.3mm out of square - sounds awful but oddly enough 12 thousanths doesnt sound quite so bad to me- decided to continue to end of project and remake if necessary - dovetail stack consists of 4 separate pieces - see photo below.

Sometimes its faster to rough out a simple piece with a hacksaw and just use the mill for a final finish and tidy up, rather than carve the whole shape out with a milling bit.

Fairly easy to break a 5mm tap inside a workpiece that took quite a lot of effort to make, was quite peeved. Even more peeved when I discovered that the broken tap was now locking two pieces together, some jiggling required to separate them.

Next job is to make the jigs to hold the cutting bits on the table.


Bill

BaronJ
4th Sep 2016, 10:02 PM
Hello Bill,


Hello,

Am almost finished this sharpening jig and looking forward to having a go at sharpening drills and end mills. An added bonus will be easier to grind 40, 55, 60, 29 etc etc degree tips.

Not much to discuss that isnt adequately covered by Harold Hall on his website or in his book see both here Grind Rest, Advanced (http://www.homews.co.uk/page145.html). He also designed a QCTP that I didnt know about and it looks interesting, see the web page.

Am quite chuffed as I felt that this might be too difficult for me - I did have to make a couple of pieces twice.


From the pictures it looks quite good. You will have to let us know how you get on with it. I started to collect some bits to make one, but I didn't get any further than that. Other projects got in the way. :U:U:U




Learnings :

When cutting the slots I learned that I need to tighten the gibs

Succesfully used tungsten carbide router bits to make the aluminium dovetails and blocks. Got a good finish on the aluminium.

Am not good at fine finishing cuts with HSS mill bit on mild steel - will make a flycutter and see if that gives me a better finish, although sharper bits make a big difference. Will try facemill with only 1 tooth and see if that is a substitute for a flycutter.


I often use TC router cutters to machine both alloys and mild steels. Though you do have to take more care with them on steel. They chip far too easily.

364072 364073

These are a couple of pictures of a fly cutter that I made. I get a really good finish on most materials, cast iron being an exception.




Am not good at cutting square blocks on mill - my dovetail stack was 0.3mm out of square - sounds awful but oddly enough 12 thousanths doesnt sound quite so bad to me- decided to continue to end of project and remake if necessary - dovetail stack consists of 4 separate pieces - see photo below.


A method that originally used to get dead square pieces on my mill, was to secure a piece of thick (20 mm) alloy plate to the bed and then after making sure the head was correctly trammed, take a fine cut across the plate. Clamp the work to this plate and then machine it. Only rotate the work piece through 90 degrees towards the column and machine it again.
Continuing until all four sides are machined. You should now have a dead square block.




Sometimes its faster to rough out a simple piece with a hacksaw and just use the mill for a final finish and tidy up, rather than carve the whole shape out with a milling bit.

Fairly easy to break a 5mm tap inside a workpiece that took quite a lot of effort to make, was quite peeved. Even more peeved when I discovered that the broken tap was now locking two pieces together, some jiggling required to separate them.

Next job is to make the jigs to hold the cutting bits on the table.


Bill

Sorry to hear about the broken tap :doh:

I wouldn't attempt to tap two pieces at the same time.

Looking forward to seeing your work holding jigs.

steamingbill
4th Sep 2016, 11:28 PM
Hello Bill,

I wouldn't attempt to tap two pieces at the same time.

Looking forward to seeing your work holding jigs.

Didnt realise I could make a flycuttter so simply, thanks. Will try the milling suggestion as well.

The workholding jigs associated with the table to date are sketched in the attached spreadsheet.

He is a very clever chap and emphasises that you can often use some of the parts you have already made on a project to help as jigs to align and cut the next parts.

Book is well worth getting out of local library.

Bill

metaler
10th Sep 2016, 07:34 AM
You have made a fine job of the sharpening jig/grinding rest Bill and I wonder, whilst you mention my website, have you studied it closely to find the articles on using it. I will also be publishing some videos showing it being used but these are a few months away.

For those who are not conversant with the web site there are around 500 pages of metalworking with another 100 relating to other things, Cabinet making being one of them.
The book style index can be found here (http://www.homews.co.uk/page463.html)

You also mention my QCTH, if you have not visited the pages regarding this in the last few weeks you will not have seen that there is now a link to a video showing the QCTH being used and having its accuracy tested, the results were repeatable to better than 0.0004 inches. The page having the link to the video is here
(http://www.homews.co.uk/page508.html)
For those who have not seen my design, it is unconventional and requires much less milling to be carried out as there are no dovetails to machine.

Harold Hall

Pete F
10th Sep 2016, 09:52 AM
Harold's site (and books) is excellent. I've always liked that rest, though have never made one. Sadly still on the to-do list. I have made the 4 facet drill sharpener however and found it wasn't for me.

metaler
10th Sep 2016, 08:00 PM
Thanks Pete for the complements.

Having made my four facet drill sharpening accessory, I would comment that sharpening a drill by the method is a critical process and cannot be done free hand, but needing some method that gives very precise positioning, such as given by my grinding rest. The method also must be fully understood, but having sharpened three or four it will become second nature.

Having sharpened the drill it will have a number of advantages over a drill sharpened with the more common form. My website here (http://www.homews.co.uk/page360.html) covers this in detail.

Do keep the jig Pete for if you ever make my grinding rest you will then be able to start using it.

Harold

KBs PensNmore
10th Sep 2016, 11:44 PM
Welcome to a TOP FORUM Harold, and thanks for the updates.
Loved reading your Workshop Practice Books series:2tsup:.
Kryn

steamingbill
11th Sep 2016, 12:12 AM
................. have you studied it closely to find the articles on using it. I will also be publishing some videos showing it being used but these are a few months away.



Harold Hall

G'day Harold,

Welcome to best forum on the planet. Will have a look for the articles about how to use the jig ......... read the manual ? Okay will do.

Any more books coming out in the future ? There's a few here would be reading them.

Bill

metaler
17th Sep 2016, 02:52 AM
I see Stanmoto that you would like to see pictures with my post, to be truthful, so would I. I do though have a problem, with over 30 forums having links to my website, finding out how to contribute to their forum is very difficult, and then having solved the problem, say regarding adding pictures, remembering the method next time you visit. I do not know whether you contribute to more than one forum but I can assure you that there are considerable differences in the way they do things.

I do have another problem, there are 1314 pictures on my website (double that if you count large and small)and locating and copying the appropriate ones is time consuming, especially if they are in different part of the site.

The best I can do at this stage therefore is to suggest you follow the link in my post, then, page though until you find pictures 12, 13, 14 and 15. If you are not conversant with the four facet method of sharpening drills then do read the text as well, as the pictures will then have more meaning.

Thanks for your interest.
Harold

jhovel
3rd Oct 2016, 07:51 PM
A belated welcome on board by me too, Harold! Just spotted your posts.
Been reading your pages and books for years. Thank you.
Nice to be able to have direct contact here.