PreciseBits

[Dominic]

Hey, Kim mentioned this supplier of inlay bits in the pantograph thread because they had bits for cutting shell inlay. Anyway, I ordered 8 various bits from them on Thursday and they turned up this morning. Pretty bloody amazing service. Haven't used them yet but they are sophisticated 3 flute bits used in cnc machines so I expect them to work well. I'll let you know how I go.

The reason I got these is because I have finished my copy/pantograph jig recently and have been practicing making moulds. The friendly plastic was a hassle so I have ended up getting some moulding poly and poring moulds for shell inlays. Done one FB with simple diamonds and the jig worked great. Now I have shell cutters I can try copying shell inlays as well.
http://www.Precisebits.com
While poring the moulds I had a guitar jig epiphany for an idea but I'll keep that under my hat for now until I get it made. This moulding stuff could have many uses in jig making.
Cheers Dom

[J.F. Custom]

Hey Dom.

I've got several of the Precise Bits range. They are superb - function beautifully and highly recommend them to others.

I have not given them a lot of use in the months I've had them, but so far they are holding there edge impressively and no breaks!! Fairly astonishing given that the smallest I have is just 0.4mm from memory... I think I've got some 0.4, 0.55, 0.8, 1.2's in the straight spirals and a couple of V bits too.

Love to see a photo of the copy jig you ended up making and are now using.

Jeremy.

[woodrat]

Hey Dom, Thanks for posting this. I (not me actually but a student) just broke my 3/32 downcut inlay bit from StewMac cutting a saddle slot in a rosewood bridge so I am in the market for some new bits. The ones I had came from StewMac and are nearly $20 each so these are much cheaper. They seem to be a different animal though grind wise...I haven't seen anything quite like them. I was never completely satisfied with the StewMac ones for routing saddle slots (perhaps that was because of my dodgy set up in the drill press....) so maybe these ones will give me cleaner slots ...here's hoping

Cheers

John

[woodrat]

...I realise that what I had (the Stewmac bits) were end mils and these jagged tooth bits they call router bits. They look like they would be good for saddle slot routing. I will order some and have a play around with them:)

Thanks again Dom...

John

[TDA]

Woodrat,

What are your saddles made of. A router bit may not be the correct tool. They are typically used for composites and do not take well to cutting softer or oily materials.

[woodrat]

Hello John, I am talking about the bridges being routed for the saddle ie cutting a slot for the saddle in a rosewood or ebony bridge. I know that my setup could be improved but I was only aware of the inlay bits available from StewMac at the time so I bought them. It is not a production situation so speed is not a consideration. A batch of bridges may be only as large as 5 or 6 so you see that it is not a large scale operation. I am just chucking them in my drill press an moving the bridge past the lowered bit by hand. It cuts an acceptable slot but it is slow. I really need to work something better out. Any suggestions would be appreciated.

[kiwigeo]

John,

IMHO I suspect part of your problem is using a router bit in a drill press. The bit isn't turning as fast as it was designed to turn and the bearings in an average drill press are designed for a thrust load not a horizontal load. I dont think changing to a different router cutter is going to help much.

Cheers Martin

[woodrat]

Thanks Martin, Yes I see...I am using the wrong tool...I have done that before! ...what I really need to do is build a proper jig to cut them with my trimmer...if I were smarter I would have already made said jig! I have a vision in my mind of one...note to self...Build it!

Cheers

John

[J.F. Custom]

I have to agree with Martin here John.

A drill press, well mine anyway, has a top speed of about 3000rpm. A router operates at 6 - 11x that speed and this is what those bits are designed for. There is a relationship between the grind style on the bit; the chip removal rate; the rpm of operation and the feed speed. All of which are what dictates the resulting cuts ease, quality of said cut and the life of the tool itself.

I am not surprised this broke the bit as the load would have been extreme though being the first, you've obviously got by ok with ultra slow feed rates. If you want to speed up/improve the process though, you would need to set up a router/dremel jig in my opinion. I don't know how you would improve the system you are using.

I know there are builders out there using the same method as yourself, but as Martin suggests, it is a compromise. The drill press is not designed for this "mill style" use. It will work, but will never be as easy or potentially yield as good results.

Some more info about bits and breakages can be found here -

http://www.precisebits.com/faqs/breaking_bits.htm

Hope it helps.

Jeremy.

**EDIT - Just saw your reply to Martin too...

[woodrat]

Thanks Jeremy, Yes you are right I did "get by" with the method using the drill press that I really only used from the suggestion in the Cumpiano book to start with and stayed with it as it was "adequate" but really I should "get with the program" and use a trimmer and jig. Hang on... I should have bought your CNC machine for the job!

John

[J.F. Custom]

Hang on... I should have bought your CNC machine for the job!

John

Ha!

Yep, that would have done the trick - possibly a bit of overkill for just saddle slots though.

Hmmm... CNC. I went, what, 16 years without one - then four or so weeks with - then without once more! Long story... But the new owner is happy with the machine I sold, whilst after several complications, I am still trying to obtain the replacement. Nevermind - perhaps one day it will be a tool added to my collection, until then, back to what I know by hand!

Jeremy.

PS - Still want a photo of the copier Dom!

[Dominic]

OK, pictures coming this weekend.
Cheers
Dom

[woodrat]

Ha!

Yep, that would have done the trick - possibly a bit of overkill for just saddle slots though.

Yes but Jeremy I would have had it drill the bridge pin holes while it was at it!

[TDA]

Wow I must have something screwed up with notifications. Sorry, here I thought no one responded.

Hello John, I am talking about the bridges being routed for the saddle ie cutting a slot for the saddle in a rosewood or ebony bridge.

In ebony and rosewood your best bet is 3 flute cutters. They are vastly stronger then 2 flute and we have had quite a bit of luck with them. If you were using smaller tooling I would recommend a shell cutter. They are even harder to break then the 3 flutes but have a limited depth of cut per pass (although that shouldn't be and issue in ebony).

I know that my setup could be improved but I was only aware of the inlay bits available from StewMac at the time so I bought them. It is not a production situation so speed is not a consideration. A batch of bridges may be only as large as 5 or 6 so you see that it is not a large scale operation. I am just chucking them in my drill press an moving the bridge past the lowered bit by hand. It cuts an acceptable slot but it is slow. I really need to work something better out. Any suggestions would be appreciated.

I do agree with the others that you will run into issue with the drill press. You will have to go slow and sooner or later the press might start complaining. I do know people that are using this method but it is not fun from my understanding. A 3 flute tool will be a little better then a 2 flute since your are adding one more cutting surface but not taking away much in flute volume (the amount of material you can pack in each flute). Might let you go a little faster.

If you need links let me know I just don't want to be seen as spamming. I usually won't even mention specific tools unless someone asks.

[Bob Connor]

If you need links let me know I just don't want to be seen as spamming. I usually won't even mention specific tools unless someone asks.

John

We appreciate you giving us some of your time to give us some expert insights into your product.

Regards

[Dominic]

Here’s my version of the pantograph. I kept it simple. I don’t think it needs a lock down bolt and it does not need to be split. To adjust depth I set the stylus on top of the mould and lower the bit until it just about touches the top of the finger board. That way the shell will be slightly high, better than too low. And when I lift the stylus the bit can’t touch the finger board. I have used it on one fb and it was simple and fast. Lift up stylus and bit, line up hole with guide lines marked on body of the jig, hold the stylus over the mould and start router and lower into fb. Simple one handed job. I have a board with pins that hold my fb lined up and it’s a simple matter of sliding the board forward until it lines up and rout away. As long as you set up the mould right to start with you will get perfectly lined up inlays.
Sorry for the bad pictures, in this light it was hard to get a decent shot of the mould but it comes out very crisp.

Pantograph 001.JPG (67.06 KiB) Viewed 17905 times

For the mould I used this easycast polyurethane resin. Sets in a couple of minutes and is more flexible than friendly plastic so you can de-mould easier. I scratched a square cross on a plastic base and then glued the diamond shell as perfectly as I could in the centre. The scratch marks showed up on the mould and give me something to help line up the mould in the jig. You can just see them in this pic.

Happy to discuss.
Cheers
Dom

Pantograph 002.JPG (57.16 KiB) Viewed 17905 times

[charangohabsburg]

Hi Dominic, your duplicator looks great!

Do you think this design with aproximately the same drawer slides would still be OK with a router (not a small laminate trimmer) or do you foresee some problems at first sight? (Such as vibration, security or whatever).

[Dominic]

Hey Markus, like I said it pretty basic and not as pretty as others I have seen. But it is accurate and square and has no slop so that’s all that really matters. These are good quality slides, the shortest heavy duty slides I could find and it is hard to feel any play in them if at all. Some of us use similar set ups for doing bindings with a laminate trimmer. With beefier body the slides would hold a trimmer easily. Extra weight makes it run smoother. But these slides could handle much more weight than what you are asking of them.

In fact, I have put together an over arm router using a pair of these same slides based on a plan from popular mechanics. Basically like my binding jig but with a deeper throat of around 500mm. Have not set it up yet as I was finishing setting up dust extraction for my router table. This new jig will attach to the wall but be removable and share the router table with my big under table router. It fits a laminate trimmer. With a pin in the table I should find many uses for it. Including cutting F holes for my archtops and any other pattern routing. I've seen a vid on youtube of a guy using one to do a very inticate fretboard inlay.
I still need to add some stops and a leaver to lower and raise the bit.

I’ll put up some pictures when its finished if anyone is interested.

Cheers
Dom

[charangohabsburg]

Thanks a lot for your detailed answer. I have only used smaller drawer slides (for my "Joint Apprentice Hobby" saw). Good to know that the bigger ones also have almost no play.

Cheers,

[Dominic]

Markus, how big a router do you want to put in a jig and what are you thinking of making?

I used 2 slides in my over arm router but you could go to 4 if you were using a large router (or 8 if you are making a large pantograph). These are rated to carry 45kg fully extended which should be heaps. Soft start router would be helpful to avoid torquing the jig too much at start up and a correspondingly larger heavier jig body and these slides would do it easily.
Cheers
Dom

[charangohabsburg]

I am thinking of making a charango body copier (could/should be used as neck duplicator as well).
Movements in vertical direction will be done by moving up the work piece / template at every pass, kind of reversed daylight mine: the mining machine moves only horizontally and the ground comes up.

My router is a Kress fm6990e. It has a detachable base (43mm collar):

It's a soft starter.

But maybe I'll design the thing to accept also an angle grinder with a lancelot chainsaw blade to get rid of much wood in less time, then switch to the router. It depends on how sturdy the copier turns out if If I decide to make an angle grinder attachment or not.

I don't worry too much about overhang, maybe I'll do the same way as I did with the saw where I used overlapping pairs of slides in order the action always happens between the supporting parts in the drawer slides. This makes a bulky machine but will be more likely idiot proof.