I make a "D Bit" Reamer

[@NoDeadlines]

Emma - Thank you for including the hardening and tempering procedure in this video. This is the first time I have clearly understood the difference between "hardening" and "tempering" - and your clear, simple video conveyed the process more clearly than any others i have viewed. And I don't need a forge to do small pieces - the gas flame is enough. Now I know. I also learned what a "D Bit" tool was and realized that I can make one of these right here in my little shop following the procedure you present. Thank you so much. I have a regular need to make small wheels called "trucks" that fit on the ends of the ink roller shafts of antique printing presses. Drilling the holes precisely has always been a challenge with my little old 6" lathe. However following your example, I could make a D bit from the same rod that I use for the shaft this wheel will mount on. I could use this tool to drill *and* ream the hole in the Delrin wheel. I think that will be much easier and far more accurate than my current procedure of center drill, then drill succeeding sizes to meet my 3/8" goal. With a D tool it will go much faster and my quality and accuracy may quite well jump to 100% in a very short time. I will also look into the feasibility of making a 1.15" D bit tool - a very long one - to be used to drill/ream a 12" tube in aluminum. This would be used to precisely match the diameter of the original "composiiton" material ink rollers used on these presses 100 years ago - which we now cast in rubber. With a 12" 1.15" dia. D bit tool, I think I may be able to bore a precise hole a long way into a block of aluminum - or convince my machine-shop-owner friend to do it on his big old lathe... That would be another breakthrough for the antique letterpress printing community worldwide! ;) Thanks!

[@grahamsengineering.2532]

Hi Emma. That's a very nice old school tool for making D-Bits you have there. It's truly amazing what some of us have tucked away in the drawers and cupboards.

[@swanvalleymachineshop]

The threading attachment & dividing head are progressing well , cheers .

[@jimmilne19]

D-bit. Well, well. One learns every day. And the filing guide is also something I haven't seen before. Very nice and useful. Perhaps you could name the manufacturer in print so we could look it up more easily. It was very nice of you to take the time to make this video (and your other fine videos) from which I/we learn. Thank you, Emma.

[@EmmaRitson]

+Jim Milne j. malcolm wild in the UK.. www.j-m-w.co.uk/

[@paulrjones3]

Great video on your technique for making D bits. I like your introduction to using a filing guide and its uses for tool and cutter making. Thanks for sharing, Paul Jones

[@pierresgarage2687]

Hi Emma, nice showing the D bit making and demo the filer guide, first time seeing that tool... Thanks for sharing, Pierre

[@EmmaRitson]

thanks pierre. looking at your camera rig today by coincidence. i may have to add some features to mk 2 of mine.

[@pierresgarage2687]

Sharing ideas this way is great at those distances, I'll also pick up some tricks from your video bank...

[@StefanGotteswinter]

Nicely shown :) That D-Bit filing guide is a neat thing, have never seen something like that before - Thanks for sharing!

[@EmmaRitson]

its also useful for making squares on clock arbours, sharpening gravers, and sharpening screwdrivers. thanks for watching!

[@gvet47]

How do you verify the reamer is to your desired diameter after filing the flats? It is an interesting fixture/jig you used to creat the reamer cutting shape.

[@100nortonfan]

Nice video, Emma, and thanks for sharing your work. I've been a machinist most of my life, and I am just beginning to do some clock and instrument repairs using a small lathe and such, but have never seen a device such as you have shown for the accurate filing of small diameters. Nice tool! Cheer, from California, USA.

[@McFingal]

Nice job Emma, I had no idea what a D bit was/is until now. I was at an auction and bought a bunch of tooling and part of it was a sack full of those things. At least two pounds worth. I guess I can put them to use now. Thanks for sharing your knowledge Emma, have a good weekend.

[@EmmaRitson]

The Texas Gun Guy thats a good score, youll find they might all be odd sizes for production jobs, but theyre worth sorting out and using.

[@freddd1962]

Emma another LBSC riddle cracked!!! Thank you!!! Where did you get the tool, is it still available?

[@SR8CReliant]

Emma: Thanks for your video. One comment: One of the profs at the local university was working with a hand drill in her garage recently. Her long hair got caught in it and she panic'd, it tore her face off along with the scalp. It was just before class finals, when she was found dead there at age 38. I have long hair like you, but keep it in a pony tail in the shop. There's no substitute for safety. That open belt is asking for trouble. Marcia in Texas.

[@vx-iidu]

LOL

[@Bartyron]

awesome! Very useful video. Thanks a lot! I am gonna make myself such a d-bit grinding tool.

[@RRINTHESHOP]

Nicly done Emma. Great tool. Thanks for sharing, Randy

[@EmmaRitson]

thanks Randy. thanks for watching!

[@Xynudu]

Hi Emma. Great video. I have some larger HSS D bit reamers I bought at a garage sale, but I've never made one. Great instructional :) Cheers. Rob

[@EmmaRitson]

thanks Rob. if you see them grab them. mostly they are from production workshops i find. thanks for watching.

[@Xynudu]

Yes, these were originally from Bridgestone rubber factory in Adelaide - probably for making extrusion molds. Rob

[@Xynudu]

Emma Ritson The ones I have are in finely ground HSS, and have a rounded nose. Also instead of a flat facet type relief, they have a ground reducing circumference - obviously professionally made and probably hideously expensive when new. Is it a good idea to give the end of the reamer some lead in angle to prevent it scoring? Cheers Rob.

[@EmmaRitson]

xynudu it probably is. the ones i am most familiar with are for putting bushes in clock and watch plates. they have a little taper on the end too and they cut well. ive a feeling this might be more to make them align with existing holes, though. probably these were used in floating holders in production machines? the square sharp end is good for a hole with a flat bottom. the beauty of these tools is that they were made or sourced to do a particular job in a particular material. ive seen all kinds of different ones.

[@Xynudu]

Interesting subject. After watching your video and your specialty slide/guide for cutting the reamer, it got me thinking whether I could do the same thing on the lathe using a tool post grinder. I'm sure I can with my full sized TPG (using the flat end/face of the stone), but as most people don't have one of those, I've been trying it with my small pencil air die grinder in the tool post to see if it's a viable alternative for the masses. It seems to work OK for grinding the flat and the facet edge - I used an old drill bit end, which is quite hard and made it slower going. I may put up a video on my little experiment. Cheers. Rob

[@FredMiller]

Nicely done Emma. I had never heard of a D bit..... Now I know how to make and use one. Thank You- Fred

[@EmmaRitson]

Fred Miller thanks for watching :)

[@CreaseysWorkshop]

That's a super cool little machine!

[@mtraven23]

that facet jig is pretty slick, but may I ask why you didn't mill that flat?

[@EmmaRitson]

At that point I didn't have a mill. Lol

[@seeweed70]

aussie aussie aussie! good on you emma, I just made one for a 25mm hole. works bloody great thanks.

[@Oldvet1946]

Nice video Emma. Those D bits are very handy. Mike

[@AmateurRedneckWorkshop]

Nice video. I don't have a D bit but at least I know how to make one now. Thanks for the video.

[@EmmaRitson]

cerberus handy tool if you dont have a reamer or flat bottom drill the right size..

[@MrEh5]

Great videos! I just subscribed. Love your little lathe,is it home made?

[@EmmaRitson]

+Bob Cartwright this lathe is a lorch AV11 from germany made sometime between 1925 and 1960.. its a work in progress as always though!

[@MrEh5]

Emmas Spareroom Machineshop I will have to look them up. I have an old belt drive Southbend 9, love the look of the old machines.

[@RyanWeishalla]

Thanks for sharing.

[@EmmaRitson]

ILGopher thanks for watching appreciate your feedback!

[@jimseefeldt2993]

Thanks Emma

[@johngurney1069]

great video but not so good for safety that bracelet on your right hand wrist an accident waiting to happen

[@ClownWhisper]

That's fine like you say for aluminum or brass but you cannot truly make a tool hard enough for steel by hand. You have to have it heat treating oven for example high speed steel you have to take it up to its temperature very slowly 400 Degrees per hour up to what is it 1450 degrees or greater I can't even remember off the top of my head

[@MakinSumthinFromNuthin]

Sure you can, hardened tool steel can cut any steel softer than the tool itself all day long and you dont have to spend hours on the ramp up to critical temperature prior to quenching. You may want to check your numbers there. Nice job on the D bit Emma

[@bigchooch4434]

Makin Sumthin From Nuthin but if the steel is soft enough to be cut, it won't be strong enough TO cut.

[@justinmaier3687]

Ryan Moulder So we should all throw away our custom ground lathe bits made from high speed steel since they won't cut anything?