Author Topic: Drilling on the lathe  (Read 3499 times)

C Ciuffetelli

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Drilling on the lathe
« on: August 07, 2017, 01:24:23 PM »
Hey everyone,

I've been drilling my barrels on my lathe for a while with great success, but all of a sudden I've been having issues. When I drill my 5/8 hole the first 1/16+ is wider then the rest of the bore which obviously makes things sloppy. I've tried everything I can think of to trouble shoot the issue including making sure the headstock is lined up to the tail stock, replace the drill bit with a new one, etc.

Does anyone have any suggestions on what the issue could be?

Thanks,

Offline Scott Ward

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Re: Drilling on the lathe
« Reply #1 on: August 07, 2017, 05:39:43 PM »
I dropped my MT2 drill chuck I use in the tailstock one time, and it was off kilter after that - had to replace.
Steelbyrd

Offline FDR

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Re: Drilling on the lathe
« Reply #2 on: August 07, 2017, 06:56:45 PM »
Are you using a "center drill" to start the holes?

Fred
Fred Roe
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C Ciuffetelli

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Re: Drilling on the lathe
« Reply #3 on: August 08, 2017, 08:32:49 AM »
Thanks for replying guys!

Scott, it's funny you say that because my chuck did fall off my bench but I didn't think anything of it. It could be as simple as that.

I've had such great luck without using a centre drill that I didn't want to mess with my setup. If replacing my drill chuck doesn't work I may have to go this route.


ben

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Re: Drilling on the lathe
« Reply #4 on: August 09, 2017, 09:41:02 AM »
I have gone to a starter hole using a forsner bit then the 5/8 and the hole is centered well. Even at that the face of the block needs to be square to the bit or it will still want to wander a bit. Some forsner bits are a little larger than the jobber bits so you may have to take a little off so they are the same size.

ben

Offline FDR

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Re: Drilling on the lathe
« Reply #5 on: August 09, 2017, 10:45:51 AM »
Square face as Ben said!  Start the hole with one of these:

https://www.harborfreight.com/center-drill-countersink-set-5-pc-60381.html

Works so well that a center drill is always mounted in one of my drill chucks. I have several drill chucks from harbor freight and they work fine also. Don't forget to use a coupon!

Fred
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Reelfoot, the original duck call. What's on your lanyard?

C Ciuffetelli

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Re: Drilling on the lathe
« Reply #6 on: August 09, 2017, 12:22:38 PM »
Thanks for the suggestions guys! So, I tried to replace my drill chuck and the problem still continues. I then took my bit out of the chuck and drilled a hole on my press and the bore PERFECT! So this confused me even more. I then checked alignment of the headstock and tailstock one more time and it doesn't seem to meet up as perfect as I thought. This got me to do a little more digging around online and I found this paragraph from Wade's website which describes my exact issue to the T!

"Axial misalignment causes the tip of the bit to “orbit” around the true center line, causing one edge of the drill to cut on the outer face – in turn causing an oversize hole.  Generally, what will happen is the entry point of the drill will be oversized, and as the drill progresses into the hole, it slowly starts to be supported by the material causing less run-out, and the bore starts to get smaller and closer to the desired size, but usually it will still be oversized – but tapered – and this will affect how the mandrel holds the blank."

Is there a simple way to troubleshoot this and fix the this alignment issue?

Thanks,

Carlo

Offline Tom Hamilton

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Re: Drilling on the lathe
« Reply #7 on: August 09, 2017, 03:34:49 PM »
Hi Carlo - You asked "Is there a simple way to troubleshoot this and fix the this alignment issue?"

It's simple to troubleshoot, put something with a center-point in both your headstock and another one in your tailstock, then bring the tailstock (point) up to the headstock (point), lock down your tailstock and look to see if your points line up perfectly.  If they don't your headstock and tailstock are not in alignment.

This has only happened to me on my midi-lathe with a swiveling headstock.  The way I align them is to use a double-ended MT2 alignment tool inserted into both the headstock and the tailstock, then I loosen my swiveling headstock, align them and tighten it back down.

Happy turning - Tom
Happily Turning on my Robust S16LB & General 25-200

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"There is no failure except in no longer trying. "
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Offline FDR

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Re: Drilling on the lathe
« Reply #8 on: August 10, 2017, 04:28:34 PM »
If your lathe worked once and you have had no catches to bend anything it may have a wood chip or other debris under the tailstock. Remove the tailstock from the lathe and clean the ways and the other clamping surfaces. Replace and see if the headstock and tailstock now lines up. Drill a test hole to check.

Fred
« Last Edit: August 16, 2017, 04:28:11 PM by FDR »
Fred Roe
Reelfoot, the original duck call. What's on your lanyard?

C Ciuffetelli

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Re: Drilling on the lathe
« Reply #9 on: August 15, 2017, 01:11:03 PM »
Fred, I did just that and it fixed the issue. There was build up under the rails of my tail stock.

Thanks for all the replies and suggestions.

Carlo

Offline FDR

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Re: Drilling on the lathe
« Reply #10 on: August 15, 2017, 03:40:36 PM »
Glad you found the problem!

Fred
Fred Roe
Reelfoot, the original duck call. What's on your lanyard?

Offline K.Ruge calls

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Re: Drilling on the lathe
« Reply #11 on: August 15, 2017, 08:30:39 PM »
 :punk:  :clap:  :punk: