Search found 1422 matches

by mechanicalmagic
Mon Aug 20, 2012 3:03 pm
Forum: General Discussion
Topic: How to make these parts
Replies: 23
Views: 4930

Re: How to make these parts

If you have a good sketch or drawing, PM it. I'll get a quote from the local laser guy.
http://www.peridotcorp.com/processes.aspx

Dave J.
by mechanicalmagic
Sat Aug 11, 2012 9:57 pm
Forum: Gunsmithing
Topic: Reaming a tube
Replies: 27
Views: 22525

Re: Reaming a tube

I'm sure nebse has been all over the Quackenbush site, but I found it very informative. http://www.quackenbushairguns.com/steel_for_airguns.htm BTW, the majority of the steels listed on Q'bush site would be compatable with a HSS reamer, although proper speed/feed and cutting lube is needed. Please r...
by mechanicalmagic
Sat Aug 11, 2012 8:02 pm
Forum: Gunsmithing
Topic: Reaming a tube
Replies: 27
Views: 22525

Re: Reaming a tube

Here in the US, there is nothing magic about hydraulic tubing. The alloy is often just mild steel. The internal & external finish and dimensions are controlled better than cheaper tubing. Some is Stainless Steel, which can be more difficult to machine. For your machining operations, you need to ...
by mechanicalmagic
Wed Aug 08, 2012 5:17 pm
Forum: General Discussion
Topic: Stacked set screws ?
Replies: 12
Views: 4932

Re: Stacked set screws ?

My guess as to the problem. You have a modern cup point setscrew, this narrow point bears down on the square steel shaft. Then the knob is used, the narrow point deforms the steel, and it all loosens up. Possible solution: Make the set screw flat across the face that bears on the square shaft. More ...
by mechanicalmagic
Fri Aug 03, 2012 8:20 pm
Forum: General Discussion
Topic: Precision Mating Surfaces
Replies: 26
Views: 6278

Re: Precision Mating Surfaces

With machining only, I doubt it. Add a reasonable lapping plate, plus skill, and I think it can be done.
Round parts will need honing and lapping.

Any irregular surfaces, not a chance. (Without LOTS of hand work.)

Dave J.
by mechanicalmagic
Wed Aug 01, 2012 11:46 pm
Forum: General Discussion
Topic: Surface Finishing Measureement
Replies: 2
Views: 1535

Re: Surface Finishing Measureement

Surface finish is rarely measured in a small shop. The equipment is expensive. However, reference surfaces are routinely used, and compared by eye, with good results. A 32 micro inch finish is quite fine, but you can achieve it using ~600 (or finer) grit sandpaper. (Approx. 32 millionths of an inch ...
by mechanicalmagic
Fri Jul 27, 2012 10:04 pm
Forum: Lathes
Topic: Indicator Mount for Lathe Way
Replies: 21
Views: 7390

Re: Indicator Mount for Lathe Way

Bill,
Personally, I like it as is. The addition of a clear chip/splash guard would be nice.
Dave J.
by mechanicalmagic
Thu Jul 19, 2012 9:41 pm
Forum: Lathes
Topic: Problem cutting groove for eccentric
Replies: 32
Views: 8620

Re: Problem cutting groove for eccentric

I ground a tool with a 0.135" width, 1/16" radius, and with a neck 7/8" long. Front clearance is 10*. I could thin it down. It is too wide and the radius is too large to work as I wish. But, I wonder how much thinner it can get and still cut 4140 longitudinally? Additionally, the ecc...
by mechanicalmagic
Wed Jul 18, 2012 9:51 pm
Forum: General Discussion
Topic: Machining Graphite
Replies: 32
Views: 8751

Re: Machining Graphite

Done some, no big deal. So far you have good suggestions. I'll add, zero rake on tools (flat top) both for lathe and drilling. It acts a little like Brass and trys to pull the tool in. SFM about 100 works well. It takes little force to shear it off, so flimsy tools work OK, never had a chatter probl...
by mechanicalmagic
Mon Jul 16, 2012 9:56 pm
Forum: Lathes
Topic: 4-Jaw Gripping Problem Figured Out - What's the Solution?
Replies: 24
Views: 4798

Re: 4-Jaw Gripping Problem Figured Out - What's the Solution

But, they aren't, they are below the diameter line. Tightening this pair of jaws tends to force the work piece towards one of the offset jaws and away from the other offset jaw. This can't be good. Well, machinists have been doing it this way for over a hundred years. (With a soft shim.) 1. Do I sh...
by mechanicalmagic
Fri Jul 13, 2012 6:44 pm
Forum: Lathes
Topic: 4-Jaw Run Out Question
Replies: 74
Views: 11179

Re: 4-Jaw Run Out Question

seal killer wrote:Dave--

I have thought about putting an indicator on a flat bar and clamping it in the tool holder. What'cha think?

--Bill
Great idea.
I think a stiff mount is a good thing. Floppy is bad. Mag bases end up in the chip pan.

Dave J.
by mechanicalmagic
Fri Jul 13, 2012 5:46 pm
Forum: Lathes
Topic: 4-Jaw Run Out Question
Replies: 74
Views: 11179

Re: 4-Jaw Run Out Question

seal killer wrote:Tell me what you think concerning what you see.
I see a very long flimsy rod thing holding a dial indicator.
Some day you are going to get a sticky dial, and the rod will flex instead of the dial moving. Just a little warning.............

Dave J.