New SuperMax 19-38 owner - a few questions that I have...

[ChadO]

Hello,

I purchased a new SuperMax 19-38 during the Black Friday sale in November 2020. It took a while to arrive, and I've now had a few weeks to try it out and I've come up with a few questions that I wanted to throw out there.  I'm curious to see what others with more experience with this model - or similar sized ones - have to say.

For some background, I have the standard 19-38 model, open stand with extension tables. I'm using the pre-cut 120 grit rolls that can be bought at Rocker or WoodCraft. I have it hooked up to a HF dust collector that's been upgraded with a Wynn filter and Oneida SDD5. I've gone through the setup/configuration videos on YouTube several times (both Laguna based, as well as hobbyist produced) and done a some minor adjustments as needed. To be clear, it didn't come way out of spec or anything crazy, but things like the conveyer rollers were not level and needed adjusting - per the Laguna video on changing a conveyer belt. Also, I checked alignment and slightly adjusted the drum using the two block method shown in the videos.

I started out by sanding some shorter 18-24" pieces of wood (cutting boards I had laying around, some maple, oak, etc) and it's gone really well, no issues. I then, in hindsight, have probably jumped to the other end of the spectrum by trying to sand an 6" wide, by 3/4" thick by 75" long, S3S red oak board. This, unfortunately, has not gone as well. This board is practice with the machine before I attempt a wider, but same thickness and length panel that I glued up.  The board has been jointed flat on one side on my jointer.  I then wanted to sand the other side smooth with the SuperMax. I understand the SuperMax is not a planer - I totally get that. In fact, I have a 15" planer which I really like. So, I'm not so much wanting to be "complaining" here as instead just wrapping my head around what are reasonable expectations for the tool. I'm not unhappy with my purchase and I know I'll get good use from it, I just need help in understanding the limitations.

When sanding the long board, I had it go through approximately 2/3 of the way without it hardly touching the board, if at all, and then hearing the drum engage and start sanding. The board continued a bit farther, and then stopped. The conveyer kept turning, but the board didn't move. With just a bit of help from me, the board moved again, but I have a nice scallop where the drum sanded while the board was stuck. It didn't seem like it was trying to take too big of a bite out of the board because with a little help it moved again. I broke out the dial calipers and measured, and the place that it hung up is almost 1.5 mm higher than the rest of the board. So, it does make sense that is where it had to work a bit harder. That brings me to my questions.

1. When it hung up, my IntelliSense never kicked in. In fact, in subsequent tests, I've never seen it engage at all.  When I turn on power to the drum and conveyer, I do see it briefly light up, so I know it can show the light (not a bad or malfunctioned LED) but I would have thought if there was enough stress to scallop the board, that IntelliSense should be engaging. I've even seen folks on YouTube demonstrating how it works, but mine is either not getting stressed to that threshold, or maybe the sensor setting is out of spec?

2. I have to turn my conveyor speed up to about 35% before my belt starts moving in any discernible way.  That seems like quite a bit to me, but maybe that's normal? I'm curious how soon others are able to see the conveyor turn when they start turning the dial. Since my machine is new, I'm in that phase of trying to understand if this is just how it works, or if there are further adjustments to be made. I just don't have a baseline to compare against.

3. Once I get more comfortable with my knowledge and using my drum sander, is it practical to expect to run longer panels through it? I'm just a hobbyist, so I don't need production cabinet shop capabilities (example a $5-10k wide belt, 3-phase, etc.) but if longer panels are going to require extra support and ideal conditions to get good results with a drum sander, then I'd want to know to save myself time and aggravation. It's a hobby I do for fun. If I need to bench sand an occasional long panel, that's totally fine. But, if a properly tuned drum sander is more than capable, then I'd be willing to keep adjusting to get it there. From some additional research that I've done, I've seen others talk about getting these scallops on longer stock and proper support beyond the extension tables seems to be contributing to their success or failure. I also see where some have said they have had to help their boards get through from time-to-time. I'm hoping to understand if that's not something to be really concerned about, or if it's on the other end of the spectrum where that should never really happen and I need to keep digging and adjusting.

Thanks! 

[wtnhighlander]

@ChadO, welcome to the forum! I can't offer advice, as I don't own a drum sander, but I'm sure the members that do will chime in shortly. Just wanted to give a good welcome!

[difalkner]

Welcome to the forum, Chad!

1. We've had our 19-38 for about 4 years and the IntelliSense kicks in often when I sand. I also bought the DRO and usually drop it 0.005" each pass.  And the IntelliSense, when it engages, does slow the conveyor belt.

2. I never looked because I automatically turn the dial to 100% each time I run the sander (well, maybe 95% of the time).  But I just tried it and the belt begins moving at 25%, not much different than yours.  Fwiw, when I slow the belt I rarely go below 50% so it not starting until 25% isn't an issue for me.

3. I've sanded boards 8' long and some as short as 6" many times with no issue.  I also sand down to about 0.080" for guitar backs/tops/sides and other projects that were very close to the max height the sander can handle.

I'm not sure if this helps but ours seems to work just fine.

David

 

[Chestnut]

59 minutes ago, ChadO said:

1. When it hung up, my IntelliSense never kicked in. In fact, in subsequent tests, I've never seen it engage at all.  When I turn on power to the drum and conveyer, I do see it briefly light up, so I know it can show the light (not a bad or malfunctioned LED) but I would have thought if there was enough stress to scallop the board, that IntelliSense should be engaging. I've even seen folks on YouTube demonstrating how it works, but mine is either not getting stressed to that threshold, or maybe the sensor setting is out of spec?

The board needs to basically be flat before it goes to the sander. Jointer then planer. What liekly happened is the variation in thickness cause the board to hang up. I've had a scallop like this happen before on pieces that don't fully engage the conveyor. For thin stock i usually hold the piece against the conveyor for a little extra insurance. Again this is not a planer and not meant to take the place of a planer. I don't think the in feed roller has 1.5mm of travel my guess is the board got wedged and the sander physically couldn't pull it through. The intillisand should have kicked on. In the event that the wood is really soft and just too narrow it's likely it didn't load the system enough. Most of the time mine triggers on wide material 12"+

59 minutes ago, ChadO said:

2. I have to turn my conveyor speed up to about 35% before my belt starts moving in any discernible way.  That seems like quite a bit to me, but maybe that's normal? I'm curious how soon others are able to see the conveyor turn when they start turning the dial. Since my machine is new, I'm in that phase of trying to understand if this is just how it works, or if there are further adjustments to be made. I just don't have a baseline to compare against.

My knob is not indexed. I never realized it until about a year after I owned it that full speed was 50% and off was 100%. I turned the knob and realized it spins on the peg. That said my conveyor doesn't visibly move until it's around 30%. I checked and full speed the indicator is on 100%. I'll admit i use the conveyor speed as on or off and don't use the variable speed feature.

 

59 minutes ago, ChadO said:

3. Once I get more comfortable with my knowledge and using my drum sander, is it practical to expect to run longer panels through it? I'm just a hobbyist, so I don't need production cabinet shop capabilities (example a $5-10k wide belt, 3-phase, etc.) but if longer panels are going to require extra support and ideal conditions to get good results with a drum sander, then I'd want to know to save myself time and aggravation. It's a hobby I do for fun. If I need to bench sand an occasional long panel, that's totally fine. But, if a properly tuned drum sander is more than capable, then I'd be willing to keep adjusting to get it there. From some additional research that I've done, I've seen others talk about getting these scallops on longer stock and proper support beyond the extension tables seems to be contributing to their success or failure. I also see where some have said they have had to help their boards get through from time-to-time. I'm hoping to understand if that's not something to be really concerned about, or if it's on the other end of the spectrum where that should never really happen and I need to keep digging and adjusting.

I don't have a lot of experience running long stock 36-48" is about the biggest I've done. That said it's more of a fine tuning machine and it's slow. babysitting each piece is something I do. That's 2 fold, 1 to get good results, 2 because the pieces that go through my sander and typically expensive figured woods that are irreplaceable and often sequence matched. Ruining 1 ruins the project.

For long pieces in feed and out feed support would be critical. The rollers that hold the piece down are not extremely strong. I don't know that machine adjustments are going to drastically improve that.

[difalkner]

I might add that a few years ago I opted for the drop-down folding in and out feed support tables.  This made all the difference in the world for running longer stock. 

I raise the folding feed tables every time I use the sander, even if I'm sanding a 10" Longworth chuck.  The advantage is that it goes to the outfeed table and stays there rather than falling off the conveyor belt.

David

[Ronn W]

Yes, I would definitely use   an extra outfeed support.  Mine is my table saw - same height - didn't plan it- just got lucky.   From experience, I always check hte board thickness for wild variation before my first pass. if the piece is critical and not replceable, I make my first pass with no cut and then lower the belt about 1/4 turn, rinse and repeat until I get my first sanding sound anywhere along the board.  Then Its n o more than 1/4 turn for each pass until the entire surface is sanded,  Piencil marks diagonally acrsso the board are good visual aid.  That's my consevative approach.

[ChadO]

Thanks everyone! I'm really enjoying the responses, it's very helpful.

I think it sounds like when the belt starts to move and the dial setting is pretty typical with what others are seeing on theirs. That's fine, I wasn't too concerned. Just hard to know with a new machine and having suspicions on the IntelliSense behaving properly. If the belt was slow to start moving based on the dial, that might be more evidence of something being off with the machine, or it could be totally normal. Just trying to eliminate variables.

I did forgot one other thing - about how much tension are you using on your conveyor belt? One of the Laguna videos shows him holding his hand on it and with probably moderate pressure, it stops the belt. If I look at my belt vs the video, mine looks to be looser then that. However, I'm able to stop it with what I'm thinking is the moderate pressure. I might have to play with that a bit more. I do wish that was a little bit more controllable or easier to gauge. It may be such that it's fine with a range of tolerances, but having a bit more measurable adjustment would be nice in that area. It's all good, we'll learn. That's half the fun. 

Edited February 6, 2021 by ChadO
typo

[Mick S]

Welcome to the forum! +1 to Chestnut's recommendations. It sounds to me like the long board was not planed to a uniform thickness before running it through through sander. Make sure your infeed and outfeed tables are set correctly.

You're not alone in trying to figure out how to get the most out of your drum sander. I teach woodworking at the local community college and that one machine causes more headaches for our maintenance tech than any other, almost entirely because people don't use it properly. It's a Powermatic with digital readout, etc. but the setup is the same.

Here's how I instruct my students to do the initial thickness calibration before running a board through the sander:

1. With the conveyor and sanding drum OFF, stick the end of the board under the rounded bolt head on the right side (after making sure that the bolt is set properly per the manual) and lower the crank until the bolt just touches the wood, then back it off a hair and pull the board back.

2. Start the conveyor (only) at a very slow speed (at least until you get the hang of it) and begin feeding the board with the top door open so you can see. At this point the drum should not turn at all. Slowly lower the drum until it just starts to make contact with the workpiece. Raise the drum up ½ turn and speed up the conveyor to pull the board through.

3. Start the drum and lower it the ½ turn your backed it off. Make sure your dust collector is on and feed the board through. It may only hit the higher spots.

4. Never lower the drum more than about 10 minutes on a clock face, or 1/6 of a turn.

I've had my 19-38 for about 4 - 5 years and use it to sand bandsawn veneers down to as thin as .020". I can hold the side to side tolerance to .0015". 

 

[difalkner]

Another thing I do is to always make certain the seam on the conveyor belt doesn't land on either roller when I turn it off.  I figure that's the most stress on that joint even though the pull is the same across the entire range of its travel.  Placing the seam on the tight roller to stay overnight or for days just seems like it's inviting a problem down the road.  So I turn it off after the seam has passed the roller and it's on the flat.

For tension I'd say mine is fairly tight, doesn't sag much at all on the underside.  I haven't watched any videos on setting the tension, though.  I've replaced one conveyor belt in 4 years, fwiw.

David

[Chet]

I think a lot of your problems are addressed by others above.  One thing I would add, I think you are running the conveyor to slow.  This will tend to give you more scallop problems in my experience.  Slow conveyor speed gives the drum a chance to dig in in one area.  Speed it up some and let the  IntelliSense work for you until you get a better feel for the conveyor speed that works for you  My dial is 1 - 10 and  Run pretty much around 7 or 8.

[Chestnut]

I think your conveyor tension is a bit low. You could probably put a bit more tension on it. I have mine quite tight for when i was doing some thin veneer. It kept lifting slightly so I tightened it. From the Supermax Manual "The conveyor belt is too loose if it can be stop-ped by hand pressure applied directly to the top of the conveyor belt. "

1 hour ago, Chet said:

My diet is 1 - 10

That's an interesting diet....

[Chet]

53 minutes ago, Chestnut said:

That's an interesting diet....

Fixed it.

[curlyoak]

I have a jet 16-32.  Starting the contact with the drum might be narrow. As the drum lowers the contact on the material gets wider. And as it gets wider I found that I needed to make 2 or 3 passes on the same setting. Then adjust down maybe a 1/8 of a complete turn.  Then 2 or 3 more passes before I lower the drum again.I keep the conveyer turned up to almost full. I think it needs full power to move wide pieces. A slow process with good results.

[ChadO]

Many thanks again for the responses - to each and everyone here! 

I just came in from doing some adjustments on the belt tension as suggested. I'll fire it up tomorrow morning to see how everything looks - it's late here now tonight and I don't want to take a chance at disturbing the neighbors just in case they could hear the dust collector.  I did find that when I tightened the conveyor belt - I can't make it slip anymore by putting hand pressure on it - that my lower end dial speed is now more responsive. Meaning, when I get to about 15%, the belt is visibly moving. I'll still run it at a much higher speed tomorrow as folks have been suggesting, but I wanted to report back that increasing the tension made a pretty noticeable difference in that regard. I'll be sure to report back my results after sending some stock through it.

[ChadO]

I just got done putting in about 1.5 hours "playing around" with it after doing a few more adjustments from last week.  I noticed that after fussing with stuff that I needed to make some tweaks to the infeed and outfeed tables.  At any rate, was able to get some time in and this is what I learned:

• Tightening up the conveyer belt really helped. It was definitely too loose.
• My Intellisand definitely works! I'm sure in-conjunction with the tighter belt, it can now feed the pieces through properly, and it kicked on and off as appeared to be needed.
• The "10-minute clock face turn" of the height adjustment looks to be a great benchmark. Depending on how much was taken off on the previous pass, that "10-minute" turn could be enough to kick Intellisand on the next pass through.
• Pieces need to be almost perfectly flat. I'm sure now that my earlier troubles with the long stock I was running through was due to some small amount of bow. However, at that time, it was exasperated by the belt tension and my inexperience with the machine. I intentionally played today with some wide, 4 foot long scrap panel that had a bit of a bow. Now, I can get it to feed through, and it'll sand it, but as one would expect, it won't remove the bow. Keeping your glue-ups as flat as possible in the clamps will make you a happy person at the sander.
• Lots of stuff I've read on the web says that they are slow at removing material and that's true. But, it's still removing some material. I probably took a 1/4" or more off a number of pieces just getting some experience built up. If you're not paying too close attention, I could see how it would still take off more material than you realized if you weren't paying attention.
• My conveyer belt and I have decided to agree to disagree on where it wants to track. I had it lined up several times over the weeks in the middle of the roller. Each time, it's drifted (if you're standing on the infeed side of the machine) to the left edge, about 3/8" off the edge of the roller. Despite my efforts to work with it, that's where it seems to end up. I've decided to accept that. It seems to stay there once it gets there, and I was approaching "machine tweak fatigue", so I'm happy to let it stay there.
• My dust collection - Harbor Freight heavily modded setup - is probably at the limits of keeping up with the sander. I number of times, depending how much sanding was done on the pass, a little pile of dust was left on the belt and would fall off onto the floor. It seemed to come and go, so I think I'm right on that boundary.

Going to have a little snack here and head back out and do a little more sanding. 

[Mark J]

13 hours ago, ChadO said:

Going to have a little snack here and head back out and do a little more sanding. 

Let me guess, a SANDwich.  

Glad that's coming together for you.

[Chestnut]

Thanks for posting a follow up. I'm glad to hear that the sander is working better with the few modifications.

On tracking. I must say that mine has been pretty consistent. It'll track towards the open side of the drum no matter what I appear to do. It moves very slowly so i usually just try and shove it over every once and a while. My recommendation is to do slow adjustments do  very small turns on the adjusters and be patient.

[gee-dub]

On 2/13/2021 at 4:51 PM, ChadO said:

• Tightening up the conveyer belt really helped. It was definitely too loose.

Interesting. the feed belt used to be aligned and tensioned at the factory.  Thanks for the follow up and glad you got it fixed.  I will add that after many years my feed belt finally needed replacing.  I went with the one from Kilngspor since I was ordering some other stuff from them anyway.  It is not a heavy cloth backed abrasive like others (including the original).  The paper has a very slick backing and although it works adequately.  There are slips here and there despite the tension being higher than I like. 

I can see now why there have been so many reports of these belts failing.  The urge to tighten the feed belt more to stop the slip would eventually result in product failure.  There have been many good reports on the feed belts from Industrial Abrasives who I also order from.  I just happen to need things from Kilngspor that day ;-(

I think  mentioned somewhere that the Laguna instructional video tells you to throw away the ceramic feed belt guides (???).  I did NOT do this and do not know why you would.  I have never had belt alignment issues beyond the first adjustments after initial hours of use on a belt.  We should also not forget that the construction of the belt contributes to the performance of the product just as the weld on a bandsaw blade does. I think you will be fine from here on out.

[ChadO]

1 hour ago, Chestnut said:

Thanks for posting a follow up. I'm glad to hear that the sander is working better with the few modifications.

On tracking. I must say that mine has been pretty consistent. It'll track towards the open side of the drum no matter what I appear to do. It moves very slowly so i usually just try and shove it over every once and a while. My recommendation is to do slow adjustments do  very small turns on the adjusters and be patient.

This is it exactly, perfect summary. You said it much more clear than what I did. Mine always wants to track to the open side, but it has been staying there once it seems to get to the spot, so I'll continue to monitor it as needed. Your part about "no matter what I do" is precisely what I was experiencing and what kept adding to my confusion when trying to get it to track in the center. I just got to the point where I felt like I had done the steps described in the manual and videos to track properly and yet it kept settling on the open side in almost the exact same place. Once there, it stops moving and all seems well, so that's where I've decided to let it stay.

[ChadO]

42 minutes ago, gee-dub said:

I think  mentioned somewhere that the Laguna instructional video tells you to throw away the ceramic feed belt guides (???).  I did NOT do this and do not know why you would.  I have never had belt alignment issues beyond the first adjustments after initial hours of use on a belt.  I think you will be fine from here on out.

Yep, you definitely saw that. It's in the video on replacing the conveyor belt. They tell you if you have them to throw them out as they are not needed.  My guess is that is before they bought out the product line, and they've determined no longer want/need to support that design? I'm with you, it was a bit odd. I didn't have them on mine so wasn't an issue, but did make me scratch my head a bit. If the machine was designed with them on there, why wouldn't you continue to use them for that model? I get that they may have tweaked the design after they took over the product, but to remove the guides on the earlier models that came with them, that did strike me as a bit odd.

I suspect that mine from the factory was probably close to the proper tension. When I went chasing the belt tracking issue (to which I thought I could keep it more centered) I likely brought the tension down too much. I'll never know for sure since that time is long gone and was right after I started using it and wouldn't have known how to record right where it was from the beginning. This kind of goes back to one of my earlier points - I really wish there was a gauge or some sort of measuring baseline you could reference. It seems like a few of these adjustments are just "watch for a while" and adjust as necessary. That's OK once you have experience and comfort in using the machine, but starting out, a new person doesn't have that understanding, and the last thing you want to do is mess up new equipment. It might be due to my nature - I work in  a Quality Control field - so I'm used to things be measured against spec and design.