Rimino

GRADUATING WITH DRILL PRESS

Recommended Posts

Does anyone have experience using the drill press for marking depth marks like described in the Strobel book?  Is this a worthy pursuit? 

I have been graduating the top and back by touch and using the caliper, then I tried using a punch also.  This was very wearisome and exhausting and then when I tried using a punch, the divot seemed always to go too far.  I’m looking for a method that’s not so painstaking so I can focus more on getting the perfect intended thickness.

I meant to ask, does anyone know of a guage I could buy to set the depth of the drill press with? Thanks everyone

Share this post


Link to post
Share on other sites

I use a drill press for thicknessing and made my own gauge out of a wedge shaped piece of rose wood with marks labeled at 1/2 mm progressive intervals . I put just enough holes in the plate to get the rough idea of the desired plate thickness and then map out the thickness about 10 times in pencil with my caliper . It takes only a half hour to remove 90% of the wood and the rest of the day before it’s finished . 

Share this post


Link to post
Share on other sites

On the good side, using a drill press in this way is pretty closely related to using a classical thickness punch.   

On the other hand, why not just use a thickness punch.  Once made, adjusting and using is super easy and fast, and very safe for you and your plate.

Threads about  using a punch.

Share this post


Link to post
Share on other sites

Years ago I made a simple jig for drilling graduations without drillpress (the only powertool I have is an electric  drill)...

A piece of flat laminate board, few blocks of wood and old hockey stick (very stiff), There's washer glued ont the stick and another is free inserted on the drillbitto prevent damage to drill chuck.

As a gauge I used another piece of the hockeystick shaped to a long wedge and marked at intervals (inserted it into machinist calipers set at desired measurementand drew line with pen. I just insert the wedge to desired thickness and drill with loose bit into the hole and tighten the chuck, then check again and go drilling. My drillbit is sharpened to sharper tip than normally so I don't compress wood. That may be your problem if the tip of the punch is not sharp enough.

 

IMG_2652.JPG

Share this post


Link to post
Share on other sites

If you do use a press it 's important to make sure your drill bit is sharp and that you let it cut without forcing or you will compress the wood and wind up with tell tale dots popping up later as you finish the plate. I use the same kind of graduated wedge as Edward to set the press and a shop made  brad point bit to insure smooth cutting. I set the thicknesses at  .3 to .5 mm thicker than final grads  and then rough to that and do the rest by eye and caliper.

There are drill presses that have nice accurate depth adjustments like the old deltas but you want an absolutely positive stop on the depth. The ones on the modern presses that are mounted on the operating handle are complete bull shit.

Share this post


Link to post
Share on other sites

I'm a tightwad who very rarely makes extravagant purchases, but in a fit of recklessness I ordered one of these a few years ago:

http://violintools.com/product/the-alberti-drill-depth-stop/

It's fab, and I've never regretted it.

On my bench drill I use a 12mm forstner for initial thicknessing/removal of material, then a sharpened spike for final thicknessing, a la the stradivari wooden press thing. The latter stage without the drill turned on.

 

Share this post


Link to post
Share on other sites
24 minutes ago, scordatura said:

Jim if you wouldn't mind can you post a pic of your anvil jig?

Here you go.  I would have posted the picture with my first post but I couldn't find it.

5a9fd1d2864aa_drillpresspunch.thumb.JPG.caa1bb2db96e6470f557544ac3e0c7cc.JPG

Share this post


Link to post
Share on other sites
6 hours ago, HoGo said:

Years ago I made a simple jig for drilling graduations without drillpress (the only powertool I have is an electric  drill)...

A piece of flat laminate board, few blocks of wood and old hockey stick (very stiff), There's washer glued ont the stick and another is free inserted on the drillbitto prevent damage to drill chuck.

As a gauge I used another piece of the hockeystick shaped to a long wedge and marked at intervals (inserted it into machinist calipers set at desired measurementand drew line with pen. I just insert the wedge to desired thickness and drill with loose bit into the hole and tighten the chuck, then check again and go drilling. My drillbit is sharpened to sharper tip than normally so I don't compress wood. That may be your problem if the tip of the punch is not sharp enough.

 

IMG_2652.JPG

HoGo can you explain more how your jig works?   I don't understand how you control the depth of the drill into the wood. 

Share this post


Link to post
Share on other sites

I have used my drill press for graduations since I started.  A few things...

Drill:  as has been mentioned, you want sharp... and as small of a diameter as you can use, to minimize cutting pressure and the resulting anvil dents.  I use a carbide micro-drill bit, the kind used in PC board drilling.  They usually have thin webs, come very sharp, and are dirt-cheap.  ~2mm diameter works best for me.

Anvil:  I prefer to use a harder surface for precision, rather than a soft one, and minimize the dent problem by keeping the forces low.  I have a large-ish diameter ball bearing glued to a post.

Gage:  similar to HoGo's tapered wood, although mine is thinner and more drawn out for precision.

In-process:  don't try to go too deep all in one shot, unless you want practice patching wormholes, as the drill tends to suck the wood up.  I will make a few drill holes and gouge down to ~2mm within my final thickness, and then make more holes to the closer value without fear of grabbing and drilling thru.

Share this post


Link to post
Share on other sites

I see no point in using a punch or drill press, because modern calipers are so great. For me a punch would only add time not save

Share this post


Link to post
Share on other sites
4 minutes ago, Don Noon said:

I have used my drill press for graduations since I started.  A few things...

Drill:  as has been mentioned, you want sharp... and as small of a diameter as you can use, to minimize cutting pressure and the resulting anvil dents.  I use a carbide micro-drill bit, the kind used in PC board drilling.  They usually have thin webs, come very sharp, and are dirt-cheap.  ~2mm diameter works best for me.

Anvil:  I prefer to use a harder surface for precision, rather than a soft one, and minimize the dent problem by keeping the forces low.  I have a large-ish diameter ball bearing glued to a post.

Gage:  similar to HoGo's tapered wood, although mine is thinner and more drawn out for precision.

In-process:  don't try to go too deep all in one shot, unless you want practice patching wormholes, as the drill tends to suck the wood up.  I will make a few drill holes and gouge down to ~2mm within my final thickness, and then make more holes to the closer value without fear of grabbing and drilling thru.

I don't think forstner bits "suck" up wood.  At least I haven't experienced it.  Good point about drill bit size.  I will look for a smaller forstner bit.  The leather pad on my anvil does make all the depths slightly higher than the measured setting, but I'm ok with a little safety buffer.

Share this post


Link to post
Share on other sites
28 minutes ago, Jim Bress said:

I don't think forstner bits "suck" up wood.  At least I haven't experienced it.  Good point about drill bit size.  I will look for a smaller forstner bit.  The leather pad on my anvil does make all the depths slightly higher than the measured setting, but I'm ok with a little safety buffer.

Hi Jim  - actually I think a larger forstner would be more useful to you to clear out some of the wood at the same time as marking the thicknesses. I find this a real time saver and with a sharp, high quality bit I never get dimples. 

Share this post


Link to post
Share on other sites
46 minutes ago, Peter K-G said:

I see no point in using a punch or drill press, because modern calipers are so great. For me a punch would only add time not save

Ditto

Share this post


Link to post
Share on other sites
35 minutes ago, Peter K-G said:

I see no point in using a punch or drill press, because modern calipers are so great. For me a punch would only add time not save

I guess that besides the technical merits of different methods, we also each simply have preferences, and differences in focus.

I can see that calipers are best if you're most interested in extreme precision.    And I can see that a drill setup can have the advantage of minimizing anvil pressure.

 

But I truly enjoy using my punch.  Also, I believe it is hands down the fastest of the methods.  You can put guide holes in as fast as you like. or at least as fast as your hand can go up and down.  At times, I've put punches in as rapidly as quick 16th notes!  Also, you can make very fine shallow marks as you reach your target.    Mine adjusts with a simple locking screw.  And to set width I use various tapered guide blocks that give the thin to thick range I generally consider good for a feature.  I have different blocks for different features.

I also like the lightness and freedom of this tool.   It doesn't weight 90 lbs or whatever.  It's just a bit of wood, like the instrument I'm making.   It goes from stowed away to full operation in just seconds, and I can take it anywhere with easy.  I do like working on the front porch when the weather's nice.

Valid or not, there's also a sense of historical connection about it.  But each to their own.  :)

 

 

 

 

 

Share this post


Link to post
Share on other sites

Also, it's light weight and small enough to just float on the bench as I work.  I can switch between the punch and gouge as much as I please with immediacy.  I love that.

Share this post


Link to post
Share on other sites

I use the drill press to get them within 2mm.  I don't worry too much about dimples because I plan on touching up the inside later.  Yeah, I use the press on the outside!   Once everything is smoothed out, I will use the punch with a sharp pin to get it closer.  So I use both.   

Share this post


Link to post
Share on other sites
4 minutes ago, JohnCockburn said:

Hi Jim  - actually I think a larger forstner would be more useful to you to clear out some of the wood at the same time as marking the thicknesses. I find this a real time saver and with a sharp, high quality bit I never get dimples. 

I've used a 3/4" forstner bit to remove material on non-violin related projects.  For me, I can hog out plates pretty quickly with my gouges.  I just like the depth hole guides to let me know when to throttle back and start taking finer cuts.   I might feel differently if I ever decide to use my 1 piece sugar maple back.  It's gorgeous, but I don't know if I can make a fiddle work with an SG of 0.76.

-Jim

Share this post


Link to post
Share on other sites

Hi All

1.0 On depth gauges

I knocked up an adjustable height jig using whatever was sitting in my scrap box. A piece of 65mm dia. aluminium off-cut, a fragment of 50mm dia.nylon rod and a M16 x 2mm pitch stainless steel bolt.

There was this crashed milk tanker that had failed to negotiate a bend in a mountain pass and had gone down the mountainside. The driver was killed. Morbid curiosity made me drive the 90km to the crash site and climb down an have a look at the wreckage. The stink of fermenting milk and the squadrons of flies drove me back up to the road - carrying a souvenir in the shape of a sheared off M16 bolt. That was in ~ 1959. It sat quietly waiting to be put to use for exactly 50 years - and three house moves!

DSC03301.thumb.JPG.ad57060590554ecc5ebb45a9322284bb.JPG

 

The divisions are at 0.1mm - quite easy to work to within 0.01mm. The nylon is a tight fit on the aluminium so that you can adjust for zero. The aluminium was stepped to fit in that hole in Brian's drill press table. In use the bolt is screwed almost all the way into the alumiium. If you want to see it - go visit Brian in Ojai California.

 

2.0 On plates being pulled up during drilling!

OK - so now you have a depth gauge and you confidently drill all the witness holes to depth.

DSC03308.thumb.JPG.7b9ffd53953f412975acad2d22214c1c.JPG

 

and Lancelot away... - a most manly pursuit.

DSC00009.thumb.JPG.5be1e9c177a34e3b7de40b86ca9c1f62.JPG

However it's hell on old wrists and is too noisy for failing hearing. So one reverts to quiet, relaxing and traditional chisels.

As you approach full depth you discover that a witness hole is too deep! - and remember that the plate once lifted with the quill of the drill and you had to pull it downward off the drill.

DSC00114.thumb.JPG.cbf30ac3ac740a96da829c0373041253.JPG

- and now have to find the off-cut from the plate. Then instant-glue a pull-shank of a pop-rivet onto the exact place between the matching lines and turned the plug down to 2mm dia. using a Dremel cutting disc and a steady hand. (Good practice is to always make two plugs - the second one one will be the better fit.) Glue the plug home with hide glue.

DSC00119.thumb.JPG.91cba06a465aae6fb91af75174dd57e0.JPG

Then if fortune favours you... the repair is as invisible as makes no difference.

 

3.0 Forstner bits - quick. Maybe too risky.

cheers edi

 

 

Share this post


Link to post
Share on other sites
7 hours ago, Peter K-G said:

I see no point in using a punch or drill press, because modern calipers are so great. For me a punch would only add time not save

I have used a drill press to help regraduate dozens of old violins.  A graduating punch or drill press is a time saver because you don't need to be constantly checking the thickness with calipers until you get close.  You just quickly remove wood until you get to the bottoms of the holes.  Then it's time to start using the calipers.

Share this post


Link to post
Share on other sites
8 hours ago, MikeC said:

HoGo can you explain more how your jig works?   I don't understand how you control the depth of the drill into the wood. 

I just lay the wedge on the rounded dowel (basswood BTW) and place the drill into the hole so it touches the desired thickness line and one more washer on top of the bit then put the handdrill over the bit with chuck tight against the washers and stick (they are there to prevent too much wear of the stick) and tighten the chuck with one hand. Done. WWHen I want to reset the depth I just barely loosen he chuck without even pulling the drill outplace the wedge under the tip and press the drill against it and tighten the chuck. ALways re-check the setting right before I start drilling and after dozen or so holes (once the bit became loose and from there on holes were shallower than planned - that is good as it is nearly impossible to drill deeper than you set the bit if anything goes wrong).

I always make sure to press the wood hard against the dowel and use ordinary drill that is sharpened with 90 degree tip angle and sharper edges with tiny bevel on cutting edge. They don't tend to pull the wood.

Share this post


Link to post
Share on other sites
14 hours ago, JohnCockburn said:

I'm a tightwad who very rarely makes extravagant purchases, but in a fit of recklessness I ordered one of these a few years ago:

http://violintools.com/product/the-alberti-drill-depth-stop/

It's fab, and I've never regretted it.

On my bench drill I use a 12mm forstner for initial thicknessing/removal of material, then a sharpened spike for final thicknessing, a la the stradivari wooden press thing. The latter stage without the drill turned on.

 

Thanks for bringing this up, I didn’t know it existed, it’s a really wise idea.  I might get one.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.