LumberJocks

Excavator #5: Drilling holes

  • Advertise with us
Blog entry by Dutchy posted 05-27-2018 08:14 AM 768 reads 0 times favorited 16 comments Add to Favorites Watch
« Part 4: Track dowels (toothpicks) Part 5 of Excavator series Part 6: Track assembly »

The tracks are made out of wooden strips. I’m sure there are orther ways for making tracks and I don’t say that mine is the best! So feel free to comment this blog and/or make a suggestion for improvements.

6

-- https://dutchypatterns.com/



16 comments so far

View Redoak49's profile

Redoak49

3530 posts in 2136 days


#1 posted 05-27-2018 10:52 AM

I really appreciate the details you in the blog and telling where you buy things. The jigs you use to make parts are very useful. Thanks

View LittleBlackDuck's profile

LittleBlackDuck

2003 posts in 968 days


#2 posted 05-27-2018 12:28 PM

Sorry to ask the obvious Dutchy, but toothpicks around the world differ… except for the fact that they are designed for teeth usage. Some people have big mouths thereby requiring suppliers to provide wider toothpicks.

I am assuming for your 2mm toothpicks you drill the outside shackles 2mm and the inside 2.2mm.

Allowing for varied toothpick sizes, would it be fair to say that the inside shackles are drilled .2mm larger than the outside ones. To state the obvious, buy the drill bits according to your supply of toothpick… ie. buy the picks first and then the drill bits (unless you have the range covered in your workshop).

-- If your first cut is too short... Take the second cut from the longer end... LBD

View Dutchy's profile

Dutchy

3085 posts in 2316 days


#3 posted 05-27-2018 01:12 PM


Sorry to ask the obvious Dutchy, but toothpicks around the world differ… except for the fact that they are designed for teeth usage. Some people have big mouths thereby requiring suppliers to provide wider toothpicks.

I am assuming for your 2mm toothpicks you drill the outside shackles 2mm and the inside 2.2mm.

Allowing for varied toothpick sizes, would it be fair to say that the inside shackles are drilled .2mm larger than the outside ones. To state the obvious, buy the drill bits according to your supply of toothpick… ie. buy the picks first and then the drill bits (unless you have the range covered in your workshop).

- LittleBlackDuck

You are right Ducky about the size, and also about the inside shackles where the hole is ,2mm bigger. I first buy two sets of 10 drill bits. One from 1.1 to 2.0 and one from 2.1 to 3mm ascending by .1 mm. A second nice benefit is that they all have the same 3.2mm shank. The chuck on my drill press start with the smallest shank of 3mm.

This drill bits you can buy for example at ebay.

-- https://dutchypatterns.com/

View GR8HUNTER's profile

GR8HUNTER

4733 posts in 860 days


#4 posted 05-27-2018 01:25 PM

well here in USA I can say toothpicks are all different sizes …. even in the same box …. LOL … SO I am choosing 3/32” dowels …. when I do drill center ones I will jump up 1 size :<))

-- Tony---- Reinholds,Pa.------ REMEMBER TO ALWAYS HAVE FUN

View LittleBlackDuck's profile

LittleBlackDuck

2003 posts in 968 days


#5 posted 05-27-2018 01:53 PM



... SO I am choosing 3/32” dowels …. when I do drill center ones I will jump up 1 size…
- GR8HUNTER
GR8, not sure whether Dutchy’s PBC drill bit will come in (or regularly available) in the size you require. If you have issues with drill bits may I suggest trying cobalt drill bits... they may be twice+ the price of HSS bits (so the 2 sises should cost between $5-$10 US for both)...
Only issue I can see is the standard incremental increase by 1/16” may be a tad too big… you’ll just have to suck it and see!

Once you use cobolt bits you’ll never go back to HSS. WHile they are more expensive, it’s the smaller guages you need strength in (rather than the 3/8”+ sizes) and they can be bought individually as required.

-- If your first cut is too short... Take the second cut from the longer end... LBD

View Dutchy's profile

Dutchy

3085 posts in 2316 days


#6 posted 05-27-2018 03:33 PM


well here in USA I can say toothpicks are all different sizes …. even in the same box …. LOL … SO I am choosing 3/32” dowels …. when I do drill center ones I will jump up 1 size :<))

- GR8HUNTER

I know the size problem of toothpicks, that is why I making more than 100 to needed lenght, but I use 80. The smallest dowels I can buy here are 3mm. When you use 3/32” I suggest to make the shackles a 1mm thicker.

-- https://dutchypatterns.com/

View bushmaster's profile

bushmaster

3239 posts in 2430 days


#7 posted 05-27-2018 03:38 PM

Extremely interesting series on the tracks.

-- Brian - Hazelton, British Columbia

View Dutchy's profile

Dutchy

3085 posts in 2316 days


#8 posted 05-27-2018 03:58 PM


... SO I am choosing 3/32” dowels …. when I do drill center ones I will jump up 1 size…
- GR8HUNTER

GR8, not sure whether Dutchy s PBC drill bit will come in (or regularly available) in the size you require. If you have issues with drill bits may I suggest trying cobalt drill bits... they may be twice+ the price of HSS bits (so the 2 sises should cost between $5-$10 US for both)...
Only issue I can see is the standard incremental increase by 1/16” may be a tad too big… you ll just have to suck it and see!

Once you use cobolt bits you ll never go back to HSS. WHile they are more expensive, it s the smaller guages you need strength in (rather than the 3/8”+ sizes) and they can be bought individually as required.

- LittleBlackDuck

Cobalt drill bits are still HSS bits. And for that reason cobalt drill bits can bow a little. This (metal) drill bits also doesn’t have a brad point and for that reason it is very hard to use them on end grain wood. With every new hole they will seek for a center point. Tungsten carbide drill bits can’t bow and on a good drill press every time the hole will be on the same spot. And also because the fact that they are very short the drill press tolerance has less influence.

Wikipedia:

Sintered tungsten carbide - cobalt cutting tools are very abrasion resistant and can also withstand higher temperatures than standard high-speed steel (HSS) tools. Carbide cutting surfaces are often used for machining through materials such as carbon steel or stainless steel, and in applications where steel tools would wear quickly, such as high-quantity and high-precision production. Because carbide tools maintain a sharp cutting edge better than steel tools, they generally produce a better finish on parts, and their temperature resistance allows faster machining. The material is usually called cemented carbide, solid carbide, hardmetal or tungsten-carbide cobalt. It is a metal matrix composite, where tungsten carbide particles are the aggregate, and metallic cobalt serves as the matrix.

It will be clear that I prefere tungsten carbide :)

-- https://dutchypatterns.com/

View LittleBlackDuck's profile

LittleBlackDuck

2003 posts in 968 days


#9 posted 05-27-2018 04:13 PM

I humbly stand corrected. I am a hacker and have never gone to the tolerances (with small drill bits) described here. My working “knowledge comes from about 4mm upwards.

I have the T&J half-track as a drawn out work in progress… Once I get to make some tracks I might be able to make my comments out of experience rather than guessing.

-- If your first cut is too short... Take the second cut from the longer end... LBD

View Dutchy's profile

Dutchy

3085 posts in 2316 days


#10 posted 05-27-2018 04:49 PM


I have the T&J half-track as a drawn out work in progress… Once I get to make some tracks I might be able to make my comments out of experience rather than guessing.

- LittleBlackDuck

That would be nice! As far as I know it’s a time ago you made a model. And your tolerances has been very, very small in the past, at least smaller than .4 mm. A blog about the build would be nice to.

-- https://dutchypatterns.com/

View htl's profile

htl

4111 posts in 1307 days


#11 posted 05-27-2018 08:37 PM

I had already said something to Gr8 about he might what to go a tad thicker for peace of mind and durability.
The super glue will definitely help here as well but may show if not careful.

Gr8 I didn’t see it was you with the Tony the tiger look but it sure fits!!! lol

-- An Index Of My Model making Blogs here on Lumber Jocks.. http://lumberjocks.com/htl/blog/116729

View LittleBlackDuck's profile

LittleBlackDuck

2003 posts in 968 days


#12 posted 05-30-2018 08:40 AM

Dutchy and audience, again talking from limited knowledge (especially about the PCB bits), tidying up the workshop, I came across this chuck I bought from Lee Valley some time ago when planning for the half-track build and concerned about the deflection of small diameter drill bits. I am guessing some of the deflection is contributed to by the length of the drill bit protruding from the chuck (amongst other issues)... if for no other reason that wont go up any further due to chuck’s throat.

This is the protrusion from my normal chuck using a 3mm drill bit (smallest bit the chuck will accept)

This is the protrusion mounted in the Lee Valley purchased Hollow-Arbor chuck,

The protrusion can be limited to just the depth of cut… the chuck’s range is .3mm (0.012”) to 4mm (5/32”).

Love my gadgets.

-- If your first cut is too short... Take the second cut from the longer end... LBD

View Dutchy's profile

Dutchy

3085 posts in 2316 days


#13 posted 05-30-2018 04:33 PM

this chuch is a very fine tool with I don.t have. Sorry for late responce. I.m out for a couple of days.

-- https://dutchypatterns.com/

View crowie's profile

crowie

2617 posts in 2099 days


#14 posted 06-03-2018 07:29 AM

Very patient careful work Dutchy

-- Lifes good, Enjoy each new day...... Cheers from "On Top DownUnder" Crowie

View LittleBlackDuck's profile

LittleBlackDuck

2003 posts in 968 days


#15 posted 06-18-2018 08:09 AM

Yo Dutchy, Many thx for the tip… though no wonder these drill are not popular,

I just received my shipment

with the plain packaging… there are no instructions on how to use.

-- If your first cut is too short... Take the second cut from the longer end... LBD

showing 1 through 15 of 16 comments

Have your say...

You must be signed in to post the comments.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com