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Review: Grizzly 1.5HP G7948 12 speed 20" Drill Press

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  • #31
    Glad to see it is working out for you. The tapered fit is a BAD design: it should have been a simple hole and key like everyone else does. And that plastic nut seems like a REALLY BAD design decision.

    I would almost think the taper is some kind of clutch to prevent something. But the belts would provide slippage if the bit stalls in the cut. So ????? Only thing I am left with is CHEAP!
    Paul A.
    Golden Triangle, SE Texas

    And if you look REAL close at an analog signal,
    You will find that it has discrete steps.

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    • #32
      Originally posted by Paul Alciatore View Post
      Glad to see it is working out for you. The tapered fit is a BAD design: it should have been a simple hole and key like everyone else does. And that plastic nut seems like a REALLY BAD design decision.

      I would almost think the taper is some kind of clutch to prevent something. But the belts would provide slippage if the bit stalls in the cut. So ????? Only thing I am left with is CHEAP!
      Agreed....keyed would be the way to go.....

      Agree again on CHEAP. I would have been far better off spending another $400 or so on a JET.

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      • #33
        I thought I'd share my experience with this model press. I bought it in 2008 solely to use for one job: making a recess cut in plastic with a 4" forstner bit. I had to over tighten the belt to keep it from slipping and the pulley on the motor shaft made a mild knocking sound right from day one. I just figured it was from being over tightened but the sound only got worse over time. I put up with it for a long time, very disgusted with it, and Grizzly tech support was useless. Finally I replaced the motor pulley and the issue disappeared! The noise and slippage that it always had since it was gone. I suspect I had a bad motor pulley. That's the only thing it could be.
        Sidenote: The new motor pulley from Grizzly did NOT come with a set screw which ticked me off, so if you buy one be sure to get a new set screw too. What cheapskates.

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        • #34
          Originally posted by Ferrous View Post
          I thought I'd share my experience with this model press. I bought it in 2008 solely to use for one job: making a recess cut in plastic with a 4" forstner bit. I had to over tighten the belt to keep it from slipping and the pulley on the motor shaft made a mild knocking sound right from day one. I just figured it was from being over tightened but the sound only got worse over time. I put up with it for a long time, very disgusted with it, and Grizzly tech support was useless. Finally I replaced the motor pulley and the issue disappeared! The noise and slippage that it always had since it was gone. I suspect I had a bad motor pulley. That's the only thing it could be.
          Sidenote: The new motor pulley from Grizzly did NOT come with a set screw which ticked me off, so if you buy one be sure to get a new set screw too. What cheapskates.

          Ya, since my machine was 7 years newer...I'm sure some things changed. I am suspicious that their 1.5hp motor doesn't really put out anywhere near that amount, but I don't feel like replacing it with a Marathon or similar to find out.

          Best of luck with yours.

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          • #35
            Oh and BTW.....

            JET 1.5hp drill press is made in China too, not Taiwan.

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            • #36
              I've seen a lot of Jet stuff over the years. Everything from good to horrible. They have machines and parts made in a lot of different places and quality is not controlled. IMHO Jet is overpriced junk (at least pretty likely to be). Same with Shop Fox. I won't buy either of them.
              Kansas City area

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              • #37
                20 inch import drill press

                Originally posted by Forrest Addy View Post
                I can't agree with your conclusion. Your disappointment in solving your particular problems (driving larger hole saws) cannot be conflated to general failure of all Grizzly drill presses for all purposes whatever as your review seems to suggest.

                Hole sawing in steel require spindle torque out of proportion to their diameter/stock removal. The 12 speed drill press you selected is a good tool for general wood and metal drilling and can be slowed to a 2110 RPM for tapping or other application where a low spindle speed seems advisable but: it's not a geared head heavy duty high spindle torque drill press.

                Your complaint it seems to me is the Grizzly drill press you bought will not drive hole saws into steel, tooling that taxes stouter geared reduction drilling machines if driven squarely under heavy feed so I don't think your machine can be condemned for that. Your machine is perfectly suited for lighter work even up to its (criminally) inflated drilling capacity of 1 1/4". Yes the G 7948 will drive a 1 1/4"dia twist drill in steel but only if stepped from a smaller diameter pre-drilled hole.

                heavily loaded plastic power transmission parts are a plague on consumer grade Asian machine tools. There is no remedy except to make all metal replacements; even beef-up/redesign to remedy deficiencies. Sad to say even today budget Asian equipment is best treated as a parts kit where the budget driven user has to make it work one way or another

                If you are committed to the G7948 drill press, I suggest you make up a larger spindle pulley or a timing belt second reduction for hole sawing that features all metal drive components. Your 1 1/2 HP motor has plenty of power. it's the second reduction that's dodgey.

                Hole sawing is a cheap expedient for hole making in steel at best. Hole saws will make a hole at low first cost and are light and portable. Electricians love them for hole making in their light sheet metal enclosures and panels.

                If you need holes in thicker steel you really need to move up to an annular cutter or some other piloted cutting system. Several options are available not all expensive. For example staging out with a line boring bar with a tail bearing mounted under the drill press table. Naturally the methods least expensive in cost tend to be the most expensive in time. I've cut 5" holes in 3/4" steel plate from the solid in a plain drill press using a General Hardware #55 circle cutter equipped with a hand ground trepanning tool - half depth from each side. It took took time and was a PITA but I got pretty good size and finish. I did have to jackshaft the spindle drive to 60 spindle RPM to obtain reasonable tool life.
                i too have a 20 inch import drill press purchased from msc about 20 yrs ago. mine was made in Taiwan.the build quality is pretty good. it even has a quil wear adjustment. my low speed is 125 rpm. any time its was subjected to a heavy load the secondary reduction belt would slip. i tried all types of belts with no success. the fix was a no 35 chain drive on the secondary reduction. i was able to bolt a plate sprocket directly to the spindle pulley. i turned a longer shaft for the intermediate pulleys and put a no 35 chain sprocket above the original pulleys. this setup does not slip ever. the chain can be removed just like the old belt and the belt can be installed if the need for higher speed occurs. but i seldom ever use the high speeds . the four on the motor pulley are all i ever need. this mod has given me the ability to use the full power of the 1.5hp motor. i have also set up a foot switch . i consider this a much safer way to use the drill press. its also great to jog the spindle for tapping. these presses are never going to match the 1000 lb industrial units but they work well enough for a home shop or light ind use. good luck with yours.

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                • #38
                  I needed a 2" hole in 3/4" m.s. plate and the only option I had was a hole saw in a 17" dp. I sawed half way through then flipped the plate over and sawed the remainder. I did have a problem with the secondary belt slippage (12 speed dp) even with light feed pressure. Blowing the chips out every so often fixed the problem. Took about 4 minutes to make the hole, so not bad.

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                  • #39
                    I have noticed that when using hole saws, there seems to be a wobble in the saw causing an enlarged hole. I found that the end of the hole saw where the arbor screws into isn't perpendicular with drum of the saw.

                    I tried putting the hole saw in the lathe and taking a skim cut off the arbor end and that improved the diameter of the hole considerably.

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                    • #40
                      Originally posted by Paul Alciatore View Post
                      On that nut, I noticed that mine is also a left hand thread. I attempted to take the nut off but it was quite tight and holding the smaller pulleys did not provide enough torque: the belts just slipped. I guess I would have to use a strap wrench on the pulley or something fabricated.
                      I have had good luck holding the spindle pulley by its largest diameter groove using a Vise-Grip chain wrench.

                      metalmagpie

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                      • #41
                        I haven't read all the replies in the thread. That said, I find import tool products often know the form of what they are imitating, but not the substance. What is a 20" drill press? 10" from spindle to column, a bunch of speeds, 1.5 hp motor and T slots in the table. At least that's kind of what a 20" drill press should appear to be.

                        The crated weight on the Grizzly is 331 pounds. And the pictures don't impress. By comparison an old Powermatic model 1200 weighs around 700 lbs. and there ain't no plastic in it either. The picture of the Grizzly looks more Fisher-Price toy than tool.

                        I, too, would be disappointed if a 20" drill press had plastic drive components and couldn't drive a hole saw through metal.

                        What you have with the Grizzly is a small home shop quality drill press that's been stretched, pulled and twisted to appear as a 20" shop quality drill press.
                        Gary


                        Appearance is Everything...

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                        • #42
                          Originally posted by Sean K. View Post
                          Ya, since my machine was 7 years newer...I'm sure some things changed. I am suspicious that their 1.5hp motor doesn't really put out anywhere near that amount, but I don't feel like replacing it with a Marathon or similar to find out.

                          Best of luck with yours.
                          I can tell you that working with the 4" forstner bit for hours at a time creates a lot of drag on the motor but it doesn't notice at all and you barely feel any difference in temp when touching the motor housing. I've found its more power than the belts/pulleys can handle.

                          I will be equipping it with a Destaco air clamp system soon to eliminate a manual quick clamp that I've used for years. Can't wait.

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