TBC, taking the plunge

[ToddMR]

Well as I was posting the other day about the new mandrel saver some people started talking about TBC. It is something I had thought about off and on, but to be honest was kind of scared of it. Then I started thinking about it more after some posts. I talked to one of the people via PM and they really helped me. So I got online and ordered me a dead 60 degree center since I already have the live center. I have been through the tutorials and seems simple enough. I don't mind so much on the one part at a time with this method of turning. I am waiting for my dead center which I hope will get here by this weekend. I saw on the latest tutorial someone mentions about drilling their bushings using a 60 degree bit? Not sure if they just call it that or if there is actually one that size? Other than that I am kind of excited to give this a shot. I am planning to hit HF this weekend and buy the digital caliper they have for $9 with the coupon I have. I figure using the bushings without drilling the hole bigger would work to just get it down close to where it needs to be. I know I can forgo the bushings all together, but not sure how brave I am on that one yet lol.

 

[KenV]

It will not even hurt -- I like to use both depending on circumstances, and with well machined bushings (Use that calipers to check them) regular bushings work to close-size.

Both ways work well, but turning between centers allows more options for variation (and a few more ways to make errors if not careful) --

Most important -- have fun learning something different.

 

[tim self]

Ditto

It will not even hurt -- I like to use both depending on circumstances, and with well machined bushings (Use that calipers to check them) regular bushings work to close-size.

Both ways work well, but turning between centers allows more options for variation (and a few more ways to make errors if not careful) --

Most important -- have fun learning something different.

IMHO, it is the most exact way of turning! LOML even commented how much better my pens looked. You will see a difference. Even after looking through inventory and deciding to redo some that looked good, I found they were ever so slightly out of round. You will not regret the decision once you get it down.

 

[ThomJ]

Todd, I too, am awaiting delivery of the tools of destruction for TBC.

 

[Pioneerpens]

good luck Todd, let us know how it goes...i've also been thinking about it, but haven't gotten there yet...

 

[IPD_Mrs]

I am planning to hit HF this weekend and buy the digital caliper they have for $9 with the coupon I have.

Look closely at the calipers before you buy. The cheap sets are just that cheap and that is ok. The problem I have with many of the calipers that HF has is the display. Example:
0.3475
I hate this display. Make the digits all the same size.
The do have a set that works like this:
0.3475
That is what I want to see. The sets they have like this come in 6" and 4" and are $19.95 and $15.95. In my opinion it is so worth the extra money.

Mike

 

[skiprat]

I saw on the latest tutorial someone mentions about drilling their bushings using a 60 degree bit? Not sure if they just call it that or if there is actually one that size? Other than that I am kind of excited to give this a shot.

If you buy one big centre drill you can do all your bushes.
Below are before and after pics of an old bushing. The first pic shows that there is an edge which isn't great to use on a 60 deg centre. The second pic shows that there is now a much larger surface to help keep the bush aligned. You also now need less pressure from the tailstock to clamp the bush/blank/bush assembly.:wink: Hope this helps:biggrin:

 

[randyrls]

I saw on the latest tutorial someone mentions about drilling their bushings using a 60 degree bit? Not sure if they just call it that or if there is actually one that size?

Skippy beat me...

Todd; Usually called a combined drill and countersink, these things come in a set of 4 and are fairly cheap. Notice they are double ended? You can find them at many outlets that have metal working tools. 60 degree are common, but you can get them in 82 and 90 degree countersink angles. I have started making my own TBC bushings. I have a metal lathe, mill, and band saw. Tool junkie!
This will drill a hole and the 60 degree countersink
http://www.grizzly.com/products/H5930

Try to find ones from India; they seem to have a higher quality. Name brand counts too but you will pay a lot more!

This one will not drill, only ream and is used to clean up the bore.
http://www.grizzly.com/products/Center-Reamer-HSS-3-pc-Set-60-186-/H2946

You have to be able to accurately mount and center the bushing for drilling. The more accurate your lathe, the better the bushing.

Oh; A LESSON I LEARNED; Put a drop of oil on the tip of the drill bit and drill and countersink run at about 1,000 RPM. If you don't the tip of the drill tends to break off and ruin the piece you are working on. DAMHIKT!

Ream at slow speed.

 

[Hucifer]

I jumped into that deep end and got my dead center and a couple of sets of bushings from Johnnycnc. I actually ended up ordering 2 centers as I forgot I had ordered on before the move:frown:
I have to agree that the pens are much better! The ones I don't have proper TBC bushings for I had resigned myself to doing the old way - but I am only doing one piece at a time and adjusting the mandrel way back to accommodate. That has really helped the out of round problem I used to have.
It had never crossed my mind to try to drill out existing bushings to work TBC! Anyone got a part # or a location to get the right bit?

 

[aggromere]

I turn all my pens between centers. I bought all my bushings from JohnnyCNC. They work great. For kits that Johnny doesn't make bushings for I just use the standard kit bushings. I have never thought about redrilling them, that's a good idea. Although some of the kit bushings are out of round and can sometimes mess the pens up.

All in all though, two things I always do now (that I learned here) is to drill and true blanks on the lathe and turn between centers instead of using a mandrell. However, I have an adjustable mandrell that I use when turning keychains and such.

 

[ToddMR]

Mike the one I am looking at is on sale and has the bigger numbers like you show below, except the last digit. http://www.harborfreight.com/hand-t...micrometers/6-inch-digital-caliper-47257.html

Thanks for the heads up!

Look closely at the calipers before you buy. The cheap sets are just that cheap and that is ok. The problem I have with many of the calipers that HF has is the display. Example:
0.3475
I hate this display. Make the digits all the same size.
The do have a set that works like this:
0.3475
That is what I want to see. The sets they have like this come in 6" and 4" and are $19.95 and $15.95. In my opinion it is so worth the extra money.

Mike

 

[jocat54]

Todd, You won't regret your choice to TBC-after you do it a few times you wonder why you ever did it any other way.

 

[mbroberg]

Todd,
Be aware that the caliper you are looking at will display measurements as decimals and metric in millimeters. It does not display fractions. That may not matter to you, but I find that I have an easier time with all three units of measurement, especially if I am searching for an alternative drill bit.