gun drilling on lathe
If there's enough interest in doing this on a conventional lathe, I'll go through all the steps. If not I'd rather not go through all the typing and picture taking. First off, what you need is about $1100.00 in an air over coolant pump and a gun drill. This is NOT like an Eldorado or other, but will result in very accurate drilling. Also what you need is a good lathe with approx. 2 - 3000 rpm with a feed rate of
.0005'' or less. The tougher and or harder the material the lower the feed rate should be. Response?
on edit: Go down a ways and I'll show you how I made this thing.
Last edited by Ray Behner; 11-23-2009 at 04:17 PM.
Sounds like an interesting read and could prove very helpful to many who don't have the facilities to gun-drill conventionally.
Always interested in learning more 'esoteric' techniques, they come in handy when others will not do.
I would read it with interest, but not be able to apply it. At least not directly; never know what I would pick up and use elsewhere.
I would very much like to see this.
If you write it I will copy it and archive it on my hard drive. I don't know when, if ever, I will piut it into application though.
I gun drilled a bunch of transformer cores on my 15" Sheldon lathe, having to work it all out myself. I will be interested in your solutions.
One more yes
I would certainly be interested.
I don't do any gunsmithing since I let my FFL expire, but I expect the techniques would be applicable to other deep-hole work.
Well good, there's interest! I have a recurring job that requires a 21'' deep hole in 1 3/4'' piston rods for a sensor in some sort of hydraulic cylinder. Getting sick and tired of peck twist drilling that deep with 4 different length drills I bought a Sterling Gun Drill for the lathe. The first pic is the coolant unit. It operates on 100 psi which blows the air through the hollow drill, plus operates an air powered piston booster pump to inject coolant into the mix. The next pic is a 1/2'' x 22'' gun drill.
Now comes the way I made a drill mount to fit my lathes. It has a 1/2'' base with a 3'' piece of bar stock welded to upright supports. I rough drilled the bar stock to 1 5/16''. Stuck the drill bit in the lathe chuck and slid the bar on it. Now I can measure the height between the bar and base plate for support ribs. The pieces are cut and holes drilled to fit the T slots of the cross slide. After I welded the assembly together I flycut the base bottom because of warpage
OK, now that it's roughed in it's mounted to the cross slide. I used dowels to align it to the T slots, but don't think it's necessary. I also made one for my 13'' Sheldon which you can see mounted where the compound was. Next to that one is the drill bushing I made to hold the drill to the support.
Tomorrow I'll show how to make things true to everything.
We'll be here, thank you. I'm most curious how you adapted your drill holder to the air and coolant, lessee, O-rings.......
Originally Posted by Robert Campbell Jr.
Nope, it's even more niftier than that! Gotta go take more pics of this mess.
Do take some pics of your stock holding/centering setup on the
back end of your head stock. Thanks for the good photos.
Why is everything so big that I have to scroll back and forth to see and read everything? Can I make it smaller on my computer?
I think this is a great thread!!!!
I personally would like to see a few more details about the gun drill itself. Having never seen one, I am very interested in it's sectional profile and it's cutting edges/point angles etc. What material is it made from? Is it ground true?
I am looking forward to the next installment.
It's because the pics are so big, there's nothing you can do about it. Ray could make the pics smaller though.
Originally Posted by moonlight machine
I'm very interested to hear how this works! Please give details on the process and the drill!
Great projects; both doing it and documenting it for us. Pictures are clear and well done. I prefer to scroll a clear picture than look at a small poorly defined photo.