PDA

View Full Version : Boring head project advice



ClintonH
02-25-2009, 11:22 PM
Got a few hours to go play in the garage again, started on the boring head I've been wanting to make. I have quit a bit done but have some questions before I finish up.
1. If I have a 40 tpi screw should the dial be 25 or 50 graduations? I was going to go 25 but this would be .002 per graduation, the norm is .001 correct?
2. I used a piece of aluminium for the for a temp gibb, can this be brass or does it need to be steel? Or maybe copper? I have copper that's why I ask.
3. The third boring bar hole on the side or end, is this useful or should I leave it out?

Here's a few pictures of the progress, it's approx 2 1/4". Thanks for any help.

http://farm4.static.flickr.com/3556/3310795608_8ae8d08957_o.jpg
http://farm4.static.flickr.com/3584/3309966655_c3a55316c7_o.jpg
http://farm4.static.flickr.com/3583/3309966699_26c22f4aef_o.jpg

Clinton

TGTool
02-25-2009, 11:35 PM
Nice work there. Some of those questions could just be a matter of personal choice.

When I made a boring head somewhat like that I did put 50 graduations on the dial. There's room for them on your circumference, and if there's ever any confusion about whether it's that much on the radius or the diameter you'll err on the safe side (more to take off).

Brass or steel would be better choices for gib material than copper. One might argue steel for strength or brass for non-galling but you're not likely to have problems with either in that situation.

I put a square hole straight through in mine but have to say I've never used it. OTOH, I've read comments from people who have used that feature so if you're giving yourself all the options you may as well go for it.

dp
02-25-2009, 11:45 PM
Beautiful work!

40 tpi is 0.025"/turn so 20 minor divisions and 5 major divisions would indicate 0.001"/div. If the dial does not become cluttered then 50 divisions would present 0.0005"/div which is a darn fine line on a boring head. You can probably estimate that at just 25 divisions.

chrsbrbnk
02-26-2009, 01:46 AM
I have used all the holes say like a really large bearing bore you might use the side hole and i have used one of the end ones for turning a boss on the side of a hit and miss model so more holes more options

JCHannum
02-26-2009, 08:37 AM
Very nice work. Brass, steel and cast iron are the usual choices for gibs and I have seen some from acetal or other rigid plastics although I would not recommend them for this application. I think copper or aluminum might not have the smooth movement you will get from harder materials.

Most boring heads graduate the dial in actual material removed, so the actual movement of the slide is doubled. Jan's suggestion of 50 grads equates to 0.001" on the bore.

The cross hole will be appreciated if you have it when you need it to do a large bore, and it is easier to put it in now than in the middle of a job if the need should arise.

Bill Pace
02-26-2009, 10:10 AM
Dang Clint, you shore do purdy work!

This is strictly 'for what its worth' - absolutely no scientific backing (Destroy this tape when finished, etc, etc)

During my recent rebuild on the Katrina South Bend lathe the shop gremlins stole the gibs for the saddle (never has shown up either!) I went to the scrap box and got a piece of ?? iron/steel and trimmed to fit, then put it on the surface grinder and made sure it was flat. Installed it and despite adjustments/oiling it just wasnt smooth.

So I've got this big cast iron base off a junked chinese planer and I band sawed a piece of cast off and repeated the grinding etc and changed the gib out --- whoa!, what a difference...smoooooth.

YMMV

ClintonH
02-26-2009, 02:43 PM
Thanks for the suggestions guys, I guess I'll either make the gibb out of cast or brass which ever I find first. The aluminum was just to lock it together so I could machine the rounded sections on the body. This and my other 2 projects started life as part of this (http://farm4.static.flickr.com/3602/3311412703_ffb433a0c5_o.jpg) had 2 given to me, they were 5"X 5" X 4". I should really stop being so cheap and buy proper sized stock. :)

I think I will also add the third hole, mine as well if I have in the vise.

And 50 graduations it is If I can get them all to fit, the dial face it only 5/8" diameter.

I'll post up some more as I get time to work on it, and thanks again.

Clinton

Bill Pace
02-26-2009, 02:50 PM
If you say youve been slicing those blocks up with a hand-held hack saw ...........:eek:

Do you know what the blocks are? Sure looks like it machines up nicely.

ClintonH
02-26-2009, 02:57 PM
No no hand hacksaw not that cheap.:) I bought a 4X6 bandsaw off kijiji after buying the lathe. I believe the guy I got them off said they were 1018 but I can't be too sure. They came from Bucyrus they build mining equipment so It could be something else. It does seem to machine pretty nice though.

Clinton

lazlo
02-26-2009, 03:22 PM
Looks great Clinton -- I gather you're following Ishimura's plans?

http://homepage3.nifty.com/amigos/boring_head/boring_head-e.htm

Peter.
02-26-2009, 03:23 PM
Bloody nice work Clinton. Looks like you've been working through the page of projects on the mini lathe workshop page. I just saw that yesterday and that and your work so inspired me that I've decided to build some of them myself. I like that the drawings are available for free and easily read too. Keep up the great work buddy, and remember - we all love pictures - the more the better :D

Peter.
02-26-2009, 03:24 PM
Looks great Clinton -- I gather you're following Ishimura's plans?

http://homepage3.nifty.com/amigos/boring_head/boring_head-e.htm


Beat me to it Lazlo :)

I really fancy that keyway-cutter, and I have a job for one too.

ClintonH
02-26-2009, 04:04 PM
Yep I contacted him a while back to express my gratitude on his webpage and all his great info and to make sure he did not mind me building some of his great tools. I changed some of the dimensions on all the projects so far but they are close for being imperial instead of metric. I should have bought some round stock for this like he started with, would have made the project easier. But having a guide like this makes getting into the metalworking hobby way easier. :)

Clinton

lane
02-26-2009, 08:36 PM
Another very nice project. Looks like you copied a Maxwell boring head . I have one just like it . Factory uses steel gib , but cast iron are brass is fine. keep up the first class work.

Oldbrock
02-26-2009, 10:37 PM
Damn nice work. For sure put the cross hole in, great for large bores also you can put your boring bar in and use it as a flycutter. Peter

ClintonH
02-27-2009, 01:39 AM
Thanks again guys, good to see I'm still on the right track. Got a bit more time to go out to the garage and work on it. I had to build something to use as an indexer as all I have is a spin indexer with one 5C collet (1"). So I built a quick and dirty (hack) indexer to use my lathe and change gears along with my drawbar and R8 collets. Here's a few pictures of the setup, so I can get some ideas on how to improve or design a better setup. It did work ok though.

http://farm4.static.flickr.com/3452/3313496208_e63acc1caa_o.jpg
http://farm4.static.flickr.com/3467/3312667223_b509dec3b2_o.jpg
http://farm4.static.flickr.com/3165/3313496302_f5b8d32eb8_o.jpg

Clinton

ClintonH
02-27-2009, 01:44 AM
Here's the tool and R8 setup on in the chuck. I just lightly clamped the collet in the chuck, just enough to hold the piece and then snugged the drawbar down to hold the gear.

http://farm4.static.flickr.com/3469/3313496352_a82bb8acb5_o.jpg
http://farm4.static.flickr.com/3550/3313518558_1a8e6d4647_o.jpg

Clinton

ClintonH
02-27-2009, 01:49 AM
And here it is mostly done, need to make a gibb still. It'll be brass just for the look of it really.:) I also need to do the black oxide and I wanted to number the main graduations but I'm having a hard time with finding some that are small enough.

http://farm4.static.flickr.com/3628/3313496408_91b6d103dc_o.jpg
http://farm4.static.flickr.com/3529/3312667415_40f3056499_o.jpg
http://farm4.static.flickr.com/3479/3313496486_feaf3cac30_o.jpg

Clinton

Evan
02-27-2009, 02:06 AM
That sure looks nice Clinton. I detect some of the same obsessive-compulsive attention to detail I have been accused of having. You will know that it's so when you find yourself polishing parts that can't ever be seen. OCD isn't always a bad thing if you direct it toward something productive. ;)

JCHannum
02-27-2009, 10:01 AM
Very nice job, and interesting use of an R8 collet in a chuck to hold the workpiece for indexing.

Here is a pic of my version of the Lautard version of, I believe, a GH Thomas boring head. The nub is to keep the cotter from getting lost when there is no boring bar installed. The gib screws & lock nuts might give you an idea.

http://i320.photobucket.com/albums/nn351/jchannum/P1060540.jpg

ammcoman2
02-27-2009, 10:17 AM
When I built a 4" rotary table a few years ago I was petrified about messing up when stamping the numbers on the periphery of the base and the slip ring. To solve the problem I took both to an engraver who did trophies etc. They did a super job.

I made the gib from brass but the key is not machine the sides only the edges. Otherwise it will curl up like a banana.

BTW I built the same Thomas boring head per the Lautard drgs as JC did but I chickened out on the dial and bought one from Sherline - I think it was about $5 at the time (black with white marks and numerals).

P.S. Keep up the good work.

Geoff

Evan
02-27-2009, 10:28 AM
If you can't find suitable stamps for marking the dial perhaps using a method that I use will do. Especially for the numbers up to six a pattern of dots the same as on dice is pretty quick for most people to recognize.

http://metalshopborealis.ca/pics5/marks.jpg

ClintonH
02-27-2009, 10:38 AM
Perfect, thank you Evan that looks like the cats patooty.:) I'll get that done tonight and get a proper punch mark on the body instead of that ugly scribe mark. And thanks for the comments guys.

Oh and while I'm posting, do any of you have any info or links on how to grind the relief angles on a tap? I tried to make a tap for the body (7/16 40tpi) but it didn't work that well, I ended up just cutting the treads on the lathe. It was a little stressful as it was my first shot at cutting internal threads, only my third attempt at threading on the lathe actually.

Clinton

Evan
02-27-2009, 11:14 AM
It was a little stressful as it was my first shot at cutting internal threads, only my third attempt at threading on the lathe actually.


ROFLMAO

The very first thing I did when I became the new owner of my SB9 back in the early 80s was to make a 6-32 screw. I had never cut threads before so I wanted to try it. I had very little lathe experience at all, mainly welding and sheet metal.

I still have that screw.

http://metalshopborealis.ca/pics/work1.jpg

ClintonH
02-28-2009, 12:41 PM
Almost finished with this but have one more question. The leadscrew and arbor are turned out of silver steel, would it be beneficial to harden either or both of these?

Clinton

TGTool
02-28-2009, 01:08 PM
Almost finished with this but have one more question. The leadscrew and arbor are turned out of silver steel, would it be beneficial to harden either or both of these?

Clinton

Theoretically yes, but practically no. The lifetime use in a home shop will probably never encounter enough wear to demonstrate a difference. In addition, there's always the possibility of warpage during heat treatment that may be difficult or impossible to correct for afterwards.

If it were intended as a production tool, some allowance for grinding after heat treat could be made.

ClintonH
02-28-2009, 03:02 PM
Ok thanks, I'll leave it alone then. Finished it off just now, wanted to get it done before I went to work. Final pictures, the dial didn't turn out quit right. Might remake it or just make sure the next boring head turns out better.:)

http://farm4.static.flickr.com/3630/3317084498_73228f8cbc_o.jpg
http://farm4.static.flickr.com/3418/3316257601_5c735e6ea7_o.jpg
http://farm4.static.flickr.com/3491/3317084614_626721eeea_o.jpg

Clinton

Peter.
02-28-2009, 04:07 PM
That's VERY nice - well done!

Paul Alciatore
02-28-2009, 04:28 PM
That is super neat. I love it.

I think the dial is OK. But if you do remake it, there are 1/16" number stamps available. I have had problems using the stamps: they do not always center the numbers the same on each one. This can produce a noticable variation in the location of the numbers on a dial, especially on a small one like this. I took the trouble to measure the deviation of each number in the set and used shims in my jig to properly center each one. A bit of a pain, but if you are going to be anal, go all the way.

And I would consider making the five's lines a touch longer. This will improve readability and help avoid mistakes.

Your Old Dog
02-28-2009, 05:30 PM
Great job Clinton. I like the black finish too. I gotta learn how to do that.

topct
02-28-2009, 05:42 PM
Use the same setup that you used to scratch the lines. Just put a sharp center punch in the tool holder and stab it with the compound.

dp
02-28-2009, 07:32 PM
Ok thanks, I'll leave it alone then. Finished it off just now, wanted to get it done before I went to work. Final pictures, the dial didn't turn out quit right. Might remake it or just make sure the next boring head turns out better.:)

You definitely need to remake it. There's only 9 divisions between ... and ....

dp

Thomas Staubo
02-28-2009, 08:06 PM
It looked right, but there is actually 49 divisions on your dial, so I guess you should remake it, yes.;)

It's 10 divisions between each long line, except on the left in this picture, it's only 9 there!


http://farm4.static.flickr.com/3628/3313496408_91b6d103dc_o.jpg

You have shown excellent workmanship so far, and this is just a tiny setback.
It would be a good idea to make every fifth line (5, 15, 25...) a little longer, as someone else mentioned.


.

ClintonH
02-28-2009, 10:02 PM
Yeah I noticed that this after noon when I was checking it with a dial. I guess I'm not as careful as I thought.:o I think I'll make a dividing head or rotary table and redo it the right way. Not sure how easy it will be to get off though It's epoxied on.

Clinton

deltaenterprizes
03-01-2009, 01:51 PM
[QUOTE= Not sure how easy it will be to get off though It's epoxied on.

Clinton[/QUOTE]

A little heat should loosen it!

dp
03-01-2009, 02:15 PM
Yeah I noticed that this after noon when I was checking it with a dial. I guess I'm not as careful as I thought.:o I think I'll make a dividing head or rotary table and redo it the right way. Not sure how easy it will be to get off though It's epoxied on.

Clinton

Turn it down in your lathe.

Your Old Dog
03-01-2009, 07:38 PM
Sorry it didn't turn out as well as you would have liked but look at the brighter side, there will be a lot of us klutz's breathing easier tonight :D

Evan
03-01-2009, 09:39 PM
Everybody makes mistakes, including me. Last night I hobbed a 287 tooth wheel for my telescope drive. Of course I have to count the teeth to make sure it came out right. Well, it has 310 teeth. !!???

I made the hob too aggressive with a bit too much gap between the teeth. This allowed the wheel to slip back very slightly on each third of a revolution of the hob causing it to make slightly thinner teeth and more of them. I am now in the process of making a new hob with spiral cut teeth and will be making a new wheel as well.

I sure like that black surface treatment. I will have to try that.

KiloBravo
03-02-2009, 09:36 AM
Anybody know what happened to New England Model Engineering Society ?

They had a great article on making Graduated Collars in this post on PM

http://www.practicalmachinist.com/vb/showpost.php?p=585170&postcount=68

But the neme-s.org site appears to be gone ?

Bill Pace
03-02-2009, 09:58 AM
Have a request Clinton .......

There is obviously MUCH interest in your method of 'blacking', would you please do a thread covering your method in more detail? ---Maybe a couple of your great pics;)

I do it with the 'cold' method from Brownells and have had pretty good results, but it dont come up to yours!

Evan
03-02-2009, 10:36 AM
I second that. Take some nice pictures and I will add the explanations to the images and post it on my new web site, with your permission. That way it will be readily available and easy to find.

BTW, my mistake on the worm wheel was dumber than I thought. I picked the wrong change gear and the hob is 13 tpi instead of 12. :rolleyes:

Thomas Staubo
03-02-2009, 03:08 PM
Anybody know what happened to New England Model Engineering Society ?

They had a great article on making Graduated Collars in this post on PM

http://www.practicalmachinist.com/vb/showpost.php?p=585170&postcount=68

But the neme-s.org site appears to be gone ?

I have no problems browsing their website, and the PDF file can be downloaded without a hitch.


.

KiloBravo
03-02-2009, 06:12 PM
I have no problems browsing their website, and the PDF file can be downloaded without a hitch.
.

Yes, it works for me now too. Who knows ???

ClintonH
03-04-2009, 01:49 AM
Finally had a chance to locate some small number/letter stamps and had a second shot at this. I used the same setup as last time with a sharper tip on the scrapping tool. I used yellow brass this time to match the gib not the rose colour it was, seemed harder.(more zinc maybe) It was hard to get a picture of it because of the shine, it's not as light as it looks in the pictures. Still not perfect but it'll do for this one.

http://farm4.static.flickr.com/3359/3327030387_0614e89cf2_o.jpg
http://farm4.static.flickr.com/3567/3327864522_21e9c21663_o.jpg

Clinton

ClintonH
03-04-2009, 01:56 AM
Have a request Clinton .......

There is obviously MUCH interest in your method of 'blacking', would you please do a thread covering your method in more detail? ---Maybe a couple of your great pics;)

I do it with the 'cold' method from Brownells and have had pretty good results, but it dont come up to yours!

I could most likely do something like that, it's actually pretty easy. My setup is pretty cheap so don't expect much on that front, it would be just to show the steps I guess.


I second that. Take some nice pictures and I will add the explanations to the images and post it on my new web site, with your permission. That way it will be readily available and easy to find.

BTW, my mistake on the worm wheel was dumber than I thought. I picked the wrong change gear and the hob is 13 tpi instead of 12. :rolleyes:

Thanks Evan, for letting me know it's ok to screw up sometimes.;) I'll see what I can do about getting something to blacken by the weekend and do a how to of sorts. I can post it here as well as send you the larger pictures to post on your site so it sticks around for others to use, if that's ok.

Clinton

Evan
03-04-2009, 05:15 AM
I'll see what I can do about getting something to blacken by the weekend and do a how to of sorts. I can post it here as well as send you the larger pictures to post on your site so it sticks around for others to use, if that's ok.


More than OK. I want to see how you do it too. I would open the site for everyone to post images on except that is too much of a security risk and I don't feel like playing moderator. Unfortunately, any on line system that allows general posting is always a target for crap.

I still have plenty of content to post and I sure won't mind some quality contributions.

BTW, shiny isn't always good. I have found that especially applies to dials. A nice fine brushed (satin) finish works best.