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

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

    New to the site, first post. Basically joined to hopefully warn others against buying a Grizzly drill press and save you some money. Below is the honest review I tried to post to Grizzly's website as well...but they refused to publish (not shocking considering the overall customer experience I received from Grizzly).

    I bought this drill press about 10 months ago to take the place of a 1HP Harbor Freight unit that had broken a motor shaft and the Marathon Motor replacement was going to take a few months to get due to a backorder.
    I bought the Grizzly 12 Speed 20" Floor Drill Press (PN G7948) with the 1.5HP motor, thinking it would be able to handle my projects with ease as my HF drill press had done for 15 years. I am sad to report I was wrong.
    When I received the unit, I was impressed with the overall heft of the drill press, but as soon as I tried to use a 1.25" holesaw to cut through 3/16" mild steel hot rolled plate....the drill press was unable to drill through it (unlike my much less expensive HF drill press that routinely has used 3" and larger hole saws to cut through 1/2" thick steel plate) without stopping the holesaw during the cut. I should mention both the HF and Grizzly are set at their slowest cutting speeds 200 and 210 respectively.

    Grizzly Tech Support was less than helpful and I finally diagnosed the problem to be the NYLON (plastic) spindle nut was not tight enough to effectively engage the tapered spindle pulley surface to the tapered insert on the spindle itself, so it was slipping. They couldn't even tell me the torque spec for the left hand plastic nut. I had to purchase a special, very large crescent wrench to tighten the nut and I had to be careful to avoid over-tightening and stripping the plastic threads. I drilled my necessary 1.25" holes and didn't really use the drill press for the next several months due to having a shop built.

    The next time I used it, it was to drill 2 and 2.5" holes with holesaws; this time in 1/8" hot rolled mild steel. The drill press just wouldn't do it without binding the holesaw and stopping with even the slightest pressure on the handles (which BTW....are made of plastic and crack out with the first use....I replaced mine with welded steel handles on metric nuts). I found the plastic nut to be too loose....and tightened it. That didn't improve the situation much, so I tightened it some more....which then flattened the threads on the plastic nut.

    Talked to Tech at Grizzly again....they sent a new pulley after I requested it...though they didn't immediately send a new tapered insert as well to make sure that if the problem was a taper mismatch, that it would be remedied with new parts. They also told me I wouldn't need a 3 jaw puller to get the old pulley off and to use pry bars and "pop" it off. When I tried that, it broke the casting on the original pulley...JFYI, buy a puller and do it the right way. Long story even longer, I called Tech and they sent out a new tapered insert as well....but when I received it, I noticed the bore is NOT concentric to the tapered surface....it is off center by .0314".


    I talked to Tech repeatedly to get the thread diameter and pitch of the plastic nut to see about getting a steel one made to replace this plastic part that doesn't have enough clamping force to mate the two tapered surfaces together. Tech couldn't tell me the answer to those questions (diameter and pitch) for several weeks. I bought metric thread gauges to ascertain the pitch....2.0 I used a set of digital and manual, calibrated calipers to tell me the max O.D. of the threads on the insert.....but it is not a standard metric size (in addition to being LEFT hand thread). The first insert sent with the drill press had TAPERED threads for some reason....as if cut by hand, not CNC. It was 35.56mm at the top, 35.7 mm at the middle and 35.78mm at the bottom. The new one was straight thread, (though again, the bore is not concentric) and a uniform 35.32mm throughout its length...but that means you can't buy a 35 or 36mm steel nut to correct the "engineering" (I use the term loosely) oversight of using a plastic nut where a steel one is called for. The quoted prices I've gotten for having an M36x 2.0 LH grade 8.8 steel nut made have ranged from $245 to $513!...and that’s not even a COMPLETELY CUSTOM 35.32mm size. And then...Tech finally confirmed my measurements of the thread diameter as 35.32mm while telling me the concentricity problem wouldn't matter (they may be right....I'll post a YouTube video about this whole thing soon, titled: Grizzly G7948 Drill Press Review). BTW, despite repeated promises to call me back with information, Tech never has. I've had to contact them to get answers; they've never called me back.

    I was seriously considering a JET brand drill press over this Grizzly. I have no idea if JET uses a steel spindle nut, but if my HF model does, I'd bet JET does as well. I tried to save a few hundred bucks since most new drill presses (including JET) are made in China anyway (though now I'm reading rumors JET is made in Taiwan and is better quality than the Chinese) and the ones made in the US (there are only 3 companies, Buffalo and Clausing being two) are $4500-7K for a 1-1.5HP. Live and learn.

    My solution has been to take the first spindle down to a local machine shop (I don't have a lathe) and have them cut the 35.32mm threads off, and thread it 1 1/4-12 LH and buy a LH steel nut. It ran about another $100 with the grade 5 unfinished nuts and shipping. On thing is: the wall of the tapered insert is pretty thin....somewhere around .080". Obviously I have to be careful how much I crank on that insert nut....but there's no way I could have had the 2nd tapered insert machined as it was so far out of concentricity that I would run out of wall thickness trying to true it up.

    And yes, I realize it is highly unlikely that Grizzly will actually post this negative review...but I'm copying this text to put in the YouTube commentary section once I do a video. Incompetent customer service, a shoddy product and lack of quality control shouldn't be covered up or rewarded IMO.

    To summarize: I have a very expensive (to me) drill press that won’t do the jobs I bought it for. The service from Grizzly has been unacceptable in terms of knowledge….they seem to simply SELL parts someone else manufacturers for them and they slap their name on it b/c they can neither troubleshoot nor provide basic answers to questions. I’ve had to put out extra money buying tools to work on it and you cannot return the drill press for a refund even if it’s still within the manufacturer’s 1 year warranty. The replacement parts have zero quality control if something can pass inspection being 31 thousandths off center. In short: DO NOT BUY A GRIZZLY DRILL PRESS.

    Oh, and FWIW, over the last 15 years...the HF model I have (Item# 43389) has been cheapened to the point of not being a good purchase either. I bought one before buying this Grizzly and the casting was of such poor pot metal that it broke while simply assembling the unit. Compared side by side, the casting is much thinner throughout the construction of my 15 year old 43389 versus the one I bought (and returned) late last year. That pretty much leaves you with JET or similar brands at around $1K+ for a 1 to 1.5HP motor.

    Hope this posts saves someone else some headaches and money in the long run.

    Best regards,
    Sean King
    Queen Creek, AZ
    Last edited by Sean K.; 06-25-2016, 04:47 PM.

  • #2
    Thanks for the review. I do like reading comprehensive review threads both good and bad!
    Play Brutal Nature, Black Moons free to play highly realistic voxel sandbox game.

    Comment


    • #3
      nice first post!

      Comment


      • #4
        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.
        Last edited by Forrest Addy; 06-26-2016, 03:21 AM.

        Comment


        • #5
          Forrest, that may not be fair.

          1) if a similar HF DP did the job, it would be fair to assume the Griz would do it. We did it at a prior employer with some cheezy DP approximately equal to a Western Auto unit. Holes up to 2 1/2" diameter or so.

          2) There's hole saws and hole saws. The sheet metal hole saws are basically annular cutters, although they actually take more oomph than some of the bimetal holesaws that look like ones for wood. I've used both kinds of saw with DPs and with hand-held drills to cut 10 gauge and similar metal, They were never an issue, although the hand held tended to be a "workout". As far as I know, all the hole saws are effectively piloted. Some with solid pilots, others with drills, but there is nobody stopping a person from putting in a solid pilot where the drill goes.

          I don't see it as that unreasonable to expect that a 1.5HP DP should do things that can be done with a Western auto or HF drill press, or with hand held drills.

          I suppose it is possible the OP was going overboard with feed rate/pressure, we have no idea, and there tend to be two sides to these situations. What he writes is reasonable, although I would have made a metal nut first and tried that.
          CNC machines only go through the motions.

          Ideas expressed may be mine, or from anyone else in the universe.
          Not responsible for clerical errors. Or those made by lay people either.
          Number formats and units may be chosen at random depending on what day it is.
          I reserve the right to use a number system with any integer base without prior notice.
          Generalizations are understood to be "often" true, but not true in every case.

          Comment


          • #6
            Amazons reviews on this model are not the best either.

            Comment


            • #7
              Originally posted by J Tiers View Post
              Forrest, that may not be fair.

              1) if a similar HF DP did the job, it would be fair to assume the Griz would do it. We did it at a prior employer with some cheezy DP approximately equal to a Western Auto unit. Holes up to 2 1/2" diameter or so.

              2) There's hole saws and hole saws. The sheet metal hole saws are basically annular cutters, although they actually take more oomph than some of the bimetal holesaws that look like ones for wood. I've used both kinds of saw with DPs and with hand-held drills to cut 10 gauge and similar metal, They were never an issue, although the hand held tended to be a "workout". As far as I know, all the hole saws are effectively piloted. Some with solid pilots, others with drills, but there is nobody stopping a person from putting in a solid pilot where the drill goes.

              I don't see it as that unreasonable to expect that a 1.5HP DP should do things that can be done with a Western auto or HF drill press, or with hand held drills.

              I suppose it is possible the OP was going overboard with feed rate/pressure, we have no idea, and there tend to be two sides to these situations. What he writes is reasonable, although I would have made a metal nut first and tried that.
              1} Grizzly lists 18 drill presses; some are jokes but a few are good machines. But they are not ALL junk nor are they ALL great. You have to shop carefully. If you make a bad choice because of low price, ignorance, bad advice, sleazy salesmanship, etc that's the breaks. But your dissatisfaction should be directed at that particular model not the whole product line - which is how I perceived the direction of the review.

              2) I spent my share of hours on the handle end of a hole saw and had swollen wrists and socks full of chips to show for it. I'm well awae they have pilots and I still have a dozen or so 1/4 dowel pins I swapped for the pilot drill so I diddn't break the pilot drill or so the flutes didn't chew up the plug before break thru. Personally, I hate hole saws but they work well when applied to the right problems. Regardless, a hole saw produces ugly imprecise holes suited for electrical fittings and welded intersections; if that's your goal, cool.

              3) I've stated many times those 12 speed drill presses suck because the second reduction belts slip under high torque load and apparently there's no simple way to fix it. Otherwise the machine would probably drive hole saws till the cows come home because there's no lack of power. OTH, if a lesser machine did the same job my assertions regarding the deficiencies of the 12 speed drill are well supported.

              While I don't fully agree about "reasonable" (my choice of drill press didn't pan out for hole sawing and tech support had no solution for me - shame on Grizzly for hiring min wage techs and not training them properly - therefore all Grizzly drill presses are junk,) I agree with the balance of your final sentence.

              Grizzly used to sell a husky 20" import drill press widely sold by other importers for about $1300. It had V/S drive, 250 to 2000 RPM, 3 power feeds, an excellent depth stop, 3MT spindle, power feed and a 3 1/4" column. It weighed maybe 800 lb. After considerable TLC it really would drill 1" from the solid in steel but it was happier doing so when I strutted the head from edge of the table closing the stress loop. I equipped it with a 3 phase motor and a VFD and wired in new electrics for power tapping with a foot switch. It was a hell of a fine drilling and tapping machine for most any work coarser than drilling 1/8 holes. And yes I ran a few hole saws in it with no problem. This brag is intended to point out that most import machinery seldom performs to specs without extra effort from the purchaser.

              Anyway, I sold it to a friend for his home fabrication shop. There's been times I wish I had it back.
              Last edited by Forrest Addy; 06-26-2016, 06:11 AM.

              Comment


              • #8
                Humm, I have to agree with Forrest. I have purchased both the Grizzly and the HF models of the 20 inch DP. The Grizzly about 7 or 8 years ago for my former employer and the HF for myself about two years ago. They look, operate, and perform much the same.

                I have not tried using large hole saws in either, but I would not hesitate to do so.

                My complaints would be a high noise level and a hard to use depth stop on both. The Grizzly did have a threaded rod for depth control, but I hate the use of regular nuts on those and I purchased a quick adjust nut for it. The HF has one of those dials on the spindle spider and I hate that even more. It is impossible to make a really precise adjustment. I plan to make my own depth stop as soon as I get the rest of my shop up and running. Both of them are quite noisy and I also plan to do some balancing on my HF.

                I was confident that the HF would handle this operation so I ran out to the shop. I could not find any 3/16" steel, but had some 1/8" so you can multiply the times by 1.5. These are some brackets that were the wrong size and I obtained about 20 of them free when the OEM replaced them. I don't know the alloy, but they are a bit harder than hardware store steel. They were to support some rather heavy, rack mounted equipment. I found a 1.5" Milwaukee hole saw on it's arbor. This is a good brand, but I don't know if it ranks with the best. The hole saw is quite sharp but the center, pilot drill could use some dressing. Anyway, here is the overall shot:



                Up close and ready to drill. I used some plain oil for cutting fluid, nothing special. The speed was set at the lowest setting: 180 RPM.



                It took about 30 seconds for the pilot drill to penetrate the 1/8" steel. As I said, it needs some attention at the grinder. The hole saw only took about one minute to go through the 1/8" steel. I did not have to use any excessive pressure and the DP did not seem to slow up by any appreciable amount.



                It's a hole! So, for 3/16" I think the times would have been 45 seconds for the pilot drill and around 90 seconds for the actual hole saw. I think I have taken longer to saw wood with similar drills.

                I believe the Grizzly I used would take a similar amount of time.

                It is possible that the Chinese have switched to these plastic parts in the last year or so. I did not see any plastic working parts in the Grizzly and I do not see any on the HF.
                Last edited by Paul Alciatore; 11-05-2017, 10:15 PM.
                Paul A.
                SE Texas

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

                Comment


                • #9
                  Originally posted by Paul Alciatore View Post
                  Humm, I have to agree with Forrest. .......
                  You SAY you agree with Forrest, but in fact you are agreeing with me!

                  My thought was that the DP ought to operate a hole saw just fine, unless someone got heavy-handed on the feed. And, your test suggests that YES, it does work fine, within the hole saw limits .

                  Forrest was suggesting (as near as I can tell) that one should NOT EXPECT the DP to operate a hole saw.

                  Now, you DO get your choice of "hole saws"..... One of these makes a better hole than the other, but not necessarily in a drill press. The steadier it is held while cutting, the better. Some DPs are sucky and loose.

                  THAT DP may suck, but most ought to do fine. And There is no particular reason why a double reduction 12 speed should not work as well as any other. I have a big single reduction Atlas/Clausing, which has driven anything I want to do with a 3/4 HP motor (it's getting 3 phase one day, when I feel like lifting the monster Crocker-Wheeler motor up there again)



                  Last edited by J Tiers; 06-26-2016, 11:02 PM.
                  CNC machines only go through the motions.

                  Ideas expressed may be mine, or from anyone else in the universe.
                  Not responsible for clerical errors. Or those made by lay people either.
                  Number formats and units may be chosen at random depending on what day it is.
                  I reserve the right to use a number system with any integer base without prior notice.
                  Generalizations are understood to be "often" true, but not true in every case.

                  Comment


                  • #10
                    I have a General 20" DP that looks very similar to Paul's that will do the hole saw task,but was not impressed with the table or column flex when you lean on the handle.I predrill the hole first,never use a drill bit in the hole saw , I always use a smooth shaft so not to oversize pilot hole.

                    Comment


                    • #11
                      J, sorry if I mixed up your posts. I am speaking about my experience in using both the Grizzly and HF 20" DPs. And in that experience, they are not top of the line by any stretch, but they are capable machines that can do serious work.

                      Of course, it is possible that the design has been downgraded in the time since I purchased those two machines. It is also possible that one particular machine of either brand can be a lemon. I do feel that Grizzly should have given much better service to the OP.

                      I have not seen any of the flexing that Tundra talks about. I wonder if that brand used a thinner wall on the column. Or a smaller diameter. There are many versions of this DP on the market and there are differences among them. I suspect the Chinese factories will work with the importer to meet a spec. or price point or both.
                      Paul A.
                      SE Texas

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

                      Comment


                      • #12
                        This is a good example of what happens when a company makes the mistake of thinking that sales is customer service. When product is manufactured offshore, customer service tends to rely on documentation rather than physical inspection to become familiar with the product. It sounds like Grizzly never actually disassembled and reassembled one of their own machines.

                        At this point, I agree with whoever said to consider this machine as a DIY parts kit and redesign and rebuild to match your own requirements. It is unlikely that Grizz has either the interest or intimate knowledge to help solve this problem.
                        I hear and I forget.
                        I see and I remember.
                        I do and I understand.
                        Confucius (孔夫子)

                        Comment


                        • #13
                          Any DP of the general size and power being discussed ought to drive those hole saws with no problem. If they don't, they are messed up, for sure. Like buying a 4 axle dump truck and finding it won't haul over a ton.

                          Originally posted by Tundra Twin Track View Post
                          I have a General 20" DP that looks very similar to Paul's that will do the hole saw task,but was not impressed with the table or column flex when you lean on the handle.I predrill the hole first,never use a drill bit in the hole saw , I always use a smooth shaft so not to oversize pilot hole.
                          That's sensible no matter what machine you use. The drill-as-pilot only works if you don't care about hole location within a few tens of thou, as is usual drilling wood.
                          CNC machines only go through the motions.

                          Ideas expressed may be mine, or from anyone else in the universe.
                          Not responsible for clerical errors. Or those made by lay people either.
                          Number formats and units may be chosen at random depending on what day it is.
                          I reserve the right to use a number system with any integer base without prior notice.
                          Generalizations are understood to be "often" true, but not true in every case.

                          Comment


                          • #14
                            Too bad you didn't return it when you determined it was plasticized, etc. Seems like that should have been a dealbreaker. Though their return policy is surprisingly unfriendly in the modern era of Amazon.

                            I have a 15" Jet I bought 20 years ago. It's been a good DP. It's smooth and quiet. I recently acquired a 1970 Powermatic 1200, so the Jet has to go. Kinda sad about that, since it was my first DP, and it would be nice to keep for woodworking, etc.

                            If I were you, I'd replace that DP with some American iron.

                            Comment


                            • #15
                              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.
                              Apparently, you missed the part where I told you my Harbor Freight 1HP DP completed this task on a very regular basis....3" diameter through hot rolled 1/2" on numerous occasions...and countless times of 3"-1" holes on 3/8" to .083" mild and alloy sheet steel as well. Most of these are speed holes or meant to be dimple died after the cut is made.

                              You make a presumption that I am talking about all Grizzly tools. I'm not. I own other Grizzly brand tools.....I specifically reviewed the G7948 model. However, to be fair to your presumption: Would I recommend their smaller DPs? Probably not, based on this experience.

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