Thread: original incra jig and fence

What kind of timber were you working with? I've just used the Incra Original do do a minor and simple DT job, mainly for the heck of it - I could have used mitre or even butt joints. I didn't achieve craftsman-quality results, but that wasn't the fault of the Incra gear. Mainly, it was the timber: radiata pine. Not for nothing is it known as "crapiata"! My beginner's technique let me down a bit, too; I didn't get the first cut dead centre. But the timber was to blame for chipping and tear-out.

One other point to watch: when you are cutting the backs of the tail boards, you do need to take the cut in a few stages; you can't get a backing board hard up against the side of the end tail, so a very gentle approach is vital to avoid tear-out.

- Michael

Hello Michael,thanks for the reply,I'm sure the timber is just cheap pine,x/bunk bed rails,but I also have tried out some off cuts of Mahogany that I had been keeping to turn,so that was an unforgivable waste,I think I need to go back to basics and follow the book page for page,I don't give in too easily,I'm also going to try a larger D/Tl.bit,maybe a cheapo is not a good idea,I realy want this to come together because I want to buy a Uni lift and and an Incra Mitre gauge,I have a very good and helpful supplier and he has whetted my appetite for new gadgets,I'm a tool and gadget freak just don't have any room left and too old now to rebuild a bigger shed,it would just be a waste, any other thoughts would be appreciated,MAC.

I love my Incra jig and i can get really good results from it. Even with Crapiata.
It sounds like your router bits are blunt or caked with resin.
It's worth taking your time and following the instructions closely till you get the hang of it.
Taking the time to set up and get your test piece spot on will make it much more rewarding.
To reduce tear out, slow down your feed rate, use a backing board and make sure your bits are sharp and clean.

I did my first DTs last week and followed the book step by step and got a great result, but I spent my time on the setup as I to wanted to make my INCRA investment worth the money. It has now encouraged me to do more DTs when I get a chance in the project I'm involved in, so keep having a go.

SB

Thank's superbunny,I will keep practicing I don't give in easy,got a little better today but still not neat,I'm going to waste a bit of Teak tomorrow,just a wee off-cut and see if my new 1/2" bit does it without splinters and chip-out,I will post an up-date if I triumph,I really want to make some nice boxs for x/mass presents,so fingers and all else crossed,
MAC.

Ok, the thing is the incra is a positioning tool, it doesn't do the job for you. You haven't told us what exactly was wrong with the dovetails you created so I'll offer some general thoughts. If you offer a detailed account of what was wrong or better yet some pics I'll try to be more helpful.

First it has to be mounted solidly. I would also recommend that the axis of the jig is perpendicular to the router bit. It doesn't have to be square to the table on a router, but if it is offset from the bit you'll get a cumulative error. To illustrate what I mean here consider the hands of a clock. They radiate out from the spindle. The spokes on a wheel usually don't, they are offset from the axle.

Second the slide needs to be precise. This is the part that is perpendicular to the fence and moves along introducing the wood to the bit.

Assuming you've got that right you need a bit is good condition of a size appropriate to the spacing your using. You have to go through the height setting proceedure to get tight joints (should be in your book), and remember to set up off the middle of your stock.

Finally you need precisely sized and well jointed stock.

If everything is right the system will just work, but you can't expect good results if your using rough warped timber, wrong sized timber, worn out or damaged bits, warped table top or haven't set up the incra rigidly and so it works smoothly.

The incra system works well and throws up fewer problems than many other jointing systems, but as with any system you have to set up right and understand the principle of how it works. Once you get it sorted I garantee you'll love it.

Very best of luck

Hi all

The accuracy of bits also plays a part, there is little use measuring the bit dimensions, you should measure the size the bit cuts.

As stated earlier in this thread, the Incra system is incredibly accurate so your part must also be accurate, stock, mounting, bits all will play a part in failure or success.

The video of the jig is worth watching quite a few times.

I hope this helps.

Regards

Grahame

Thank you G/what,where I'm still srewing up I think is I didn't match thickness of timber to cutter,I've also now honed all my D/Tl. cutters so out of the garden tomorrow and into the shed for another go,also have any of you chaps really thought much of your Original JIG,and wished they had bought one of the larger models instead,is it possible to get really good joints on it,I'm losing faith and getting frustrated with it,I think I will build a dedicated router table and get Woodpeckers plate and lifter,just to see if it's me that's a plonker,anyhow I'll keep trying to improve,post you again,MAC.

There is nothing wrong with the origional jig. I have an origional and a ls/ts system. Obviously it lacks 25" of travel and the micro adjust, but it's smaller, lightweight and obviously cheaper.

If your cutting dovetails or whatever it'll be fine, but you HAVE to bolt everything down properly, have a flat table and follow ALL the setup steps.

Shortcuts, that way lies disaster...

I recommend going to incra.com and viewing the videos there. They aren't as good as the dvd but they do offer some good clues. All positioners work on the same principle so all videos are relevant, with caveats.

Here I am again,I seem to have solved the dovetail cuts,well i hope!!!!!,now I can't seem to get the simple box joint right,I cut them nice and clean but the last cut ends up with a very thin outside sliver remaining,I have tried a dozen diferent settings ,In-Out and blank the line and to the book,I'm using a brand new Trend straight 3/8" cutter,and can't get the clean cut at the last cut,always the thin sliver left,what am I doing wrong,thanks for looking, MAC.

Make sure you centre your workpiece acuratelly. Sounds like you are a sliver to one side. Do you have the template library? Place your workpiece on top of the full size patterns to determine the best template for that size timber.

Hi NCA.I think you may just have kicked my ass, that is what I'm not doing,I didn't realize you had to center each time for a set of cuts,oh boy I'm really getting old and thick,and I will now pick a template to suit the timber thickness,thank you friend for the advice,once I have it all doing smooth and perfect each time I want to buy an Ultra-lite set-up and a 27 miter gauge plus a plunge lift but all really pricey for me to justify just yet,I watched and bid for a LS.24. but the guy wouldn't ship from the USA.& it went fairly priced,now I find you can have an accommodation postal address and they ship on to you,what a downer,still I'm not ready for it yet, MAC.