Grizzly G9729 Mods

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Dozerash
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Joined: Wed Feb 05, 2020 2:09 pm

Grizzly G9729 Mods

Post by Dozerash » Fri Feb 14, 2020 9:15 am

Can anyone that has the Grizzly G9729 share there mods and accessories? Thanks


Torch
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Joined: Wed Mar 17, 2010 7:58 am
Location: Muskoka

Re: Grizzly G9729 Mods

Post by Torch » Fri Feb 14, 2020 11:27 am

I also added a DRO (Sinpo 3-axis) and felt wipers for the carriage. But I can't seem to find those threads now.

Dozerash
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Re: Grizzly G9729 Mods

Post by Dozerash » Mon Feb 17, 2020 11:04 am

Thanks!

Dozerash
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Re: Grizzly G9729 Mods

Post by Dozerash » Thu Feb 25, 2021 7:26 pm

Did you find the post on the added DRO?

Dozerash
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Joined: Wed Feb 05, 2020 2:09 pm

Re: Grizzly G9729 Mods

Post by Dozerash » Thu Feb 25, 2021 7:30 pm

I have a few jobs to do on my Grizzly G9729. One is making new caster shafts for my mower. The shafts are 1 inch that needs 4 holes drilled and three snap ring grooves. I also need to bore some big holes. Any suggestions on tooling and set up? Thanks.

Torch
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Joined: Wed Mar 17, 2010 7:58 am
Location: Muskoka

Re: Grizzly G9729 Mods

Post by Torch » Thu Feb 25, 2021 8:04 pm

Are the holes in a row along the shaft? A vise or possibly v-blocks and clamps to hold it and a drill chuck in your mill.

Or cross-drilled at angles to each other? Again, a vise with some means of precise rotation for cross-drilling. A 5c collet and square (or hex) collet holder works well for a 1" shaft. A rotary head, or spin indexer with a chuck is another possibility. But depending on the required precision, a vise alone might be sufficient -- clamp, drill, insert a rod, check for vertical, unclamp, rotate so the rod is horizontal, reclamp.

Or into the ends of the shafts? Use your lathe with a chuck in the tailstock. (the first time you do this will seem so unnatural -- the drill bit sitting still and the metal spinning around it!)

For snap ring grooves, you will need to grind a tool bit a few thou wider than the width of the snap ring, similar in shape to a parting tool. Set it on centre, touch off the shaft, set your dials or DRO to zero, then straight in to the required depth so the circumference of the groove matches the inner diameter of the snap ring. Use lots of cutting oil!

Boring big holes in what? In the end of a piece of round stock, you just need a boring bar and your lathe. Drill the end undersized and not quite to depth as a start. Then finish with the boring bar. You can do the same thing in a square piece of material provided it fits in your 4-jaw chuck, but it takes a bit of finesse to get things centered on the hole centre. You can get pretty close by centre punching the hole first then using the tailstock centre as a guide while adjusting the chuck. Or use a centre-finder in the tailstock chuck.

For greater precision, turn a piece of drill rod to a 60° point on one end and drill a hole with a 60° centre bit in the other. Then place the point of the rod in the centre-punched dimple and "pinch" that rod between your tailstock centre. Now set up a DTI or dial indicator against the side of the rod near the chuck. Rotate the chuck by hand and adjust the 4 jaws until there is no more wobble in the shaft -- just like adjusting a piece of round stock in the 4-jaw.

For larger pieces of flat stock, you will need a boring head for your mill, a boring bar to fit the head, and some means of holding the material up off the table. A vise, or parallels and clamps. And again, some means of finding centre. But you can do that using an edge finder then simply measuring from two edges to the desired centre of your hole. Or a centre finder to a centre punched dimple. Again, start by drilling the hole, then open it up with the boring head and bar.

MarkWarrec019
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Re: Grizzly G9729 Mods

Post by MarkWarrec019 » Mon Jun 14, 2021 2:04 am

I did some work on Grizzly G0555 and it's working good , like the one feature I like to work with 3200RMP.

pete
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Re: Grizzly G9729 Mods

Post by pete » Mon Jul 19, 2021 6:06 pm

As Torch mentioned, boring holes in what, how big are the parts, how big/deep are the holes. The off shore clones of the Criterion heads aren't great but can be made to work. If your in North America I'd buy an imperial head if you don't already have one. The Criterion DBL 202 head uses 1/2" shank tooling and Criterion offer what's called a replaceable carbide tip cross hole boring bar in that 1/2" diameter. It's used to bore through holes up to maybe 6" in diameter if your machine will run at a slow enough rpm. Criterion won't sell directly to us, but even though it's not in the MSC catalog they can get them. About $80 when I bought mine.

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