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Hi Everyone,

I'm looking for some info from people who have Jet (Performax) drum sanders. Mine is a 22-44 but I guess the particular issue I have may have come up with the 16-32 model as well.

The issue - when I lower the drum head down to sand to approx 3mm (.12") or less, I hear contact between the sanding belt and conveyor belt. This only happens on a certain section of the conveyor belt and it appears to be around the "join" in the conveyor belt. The belt seems to have a slight "bulge" upwards both in front of and behind the join. As this is a new machine (< 4 months old) and hasn't been heavily used, I don't think this has been caused by wear. I noted that my previous Jet drum sander had the same issue.

My question is whether other Jet owners have experienced this issue and if so, how they rectified the issue. I don't believe this is a drum alignment problem. I feel confident I have aligned the drum correctly and accurately. I believe I have tensioned to conveyor belt as per the Jet manual. I'm wondering whether further tensioning the conveyor belt may lessen the "bulge" but I am wary of overtensioning and perhaps bending the rollers.

As a final question, am I asking too much to be able to sand back and sides down to 2mm (.078")without using some sort of sled (which would probably eliminate the issue)? Although Jet describes the lower limit as 0.8mm (1/32"), is this just not possible given the conveyor belt construction?

Would a poly belt fix this issue if they are available for the 22-44?

I hope some experienced drum sander users will be able to shed some light on this issue for me both in terms of set up and usage when they sand backs and sides down to final thickness.

Thanks,
Steve.

I have a 16-32 and can sand down to around 1mm and thinner, however once I do get down around 2-3 mm I do hear intermittent contact between the sanding belt and the conveyor. I have learned to just live with it. The contact is very light and is not damaging the conveyor or the paper I have on the drum. It may be caused by the convenor belt being stretched in some areas, or if the paper on your drum is not totally tight.

One thing to be aware of when sanding thin stock is that the part of the conveyor belt where it is joined will causes a slight rise in the conveyor. This means if the stock you are sanding goes through the sander while on the joined part of the conveyor belt you are going to get a slightly thinner spot. When I do the final thicknessing on parts I wait until that portion of the conveyor goes through the sander and start my stock right behind it (I hope that makes sense).

Josh

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If you eventually conclude there is a more serious problem, be sure to contact JET while still under warranty.

I have had a 22-44 for 6 or 7 years. I echo what Josh says. I just live with a little belt contact when getting down there and watch where the seam is. I've gone down to 0.050-0.060 for laminated sides with no problem. If it's smaller parts and I want to go thinner I usually use a carrier board with some sandpaper on it or a part holder for stuff like saddle blanks.

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I've got the 16-32. My conveyor belt makes gentle contact with the drum because my dust collector is lifting it off of the plattern. To avoid this I simply open up another dust gate to reduce the suction at the sander. Try turning your dust collector off and see if you are still making contact. Like the others.. I'm able to sand down to .020" with no problems.

Michael

My 10/20 gets light contact especially if the paper on the drum is not perfectly tight. It lifts slightly off the drum and you get a light intermittent scratching noise. I haven't seen I to cause problems yet.

Hey....this is weird. Somebody else on a different forum is going through the EXACT same thing as you, even the same model! I'll follow this closely and let him know what the outcome is

Jeff,

I've been "busted" . I'm a member of a few forums so I cross-posted. Apologies if that is "bad practice".

Regards,
Steve.

No way man. Both great forums and a bunch of members belong to both. I was just screwing around. Welcome!

Cross posting is great I think! Hit a bigger target.

I have a 16-32 and I too have this issue. It's caused mostly by the drum paper being loose either on the ends or all around which can happen as the paper seems to stretch a bit when it gets warm. My issue is usually at the right side of the drum, closet to the coupler. I can never seem to get the paper tight there and when going thinner than 0.065" I can start to hear the slapping of the drum belt on the feed belt. It wears the drum belt down pretty quick in that location and I can't use that section of the drum or I'll just burn the wood as there is no abrasive left to do the work.

Try to get the drum belt really tight, check it often during use as it will stretch a bit.

I think a sled is a good idea for thin stick like sides or bindings. I should probably make one myself.

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As I wrap the drum I leave an 1/8" gap between wraps. This allows the tensioner to do its job. I'm truly able to sand my perflings down to .020" with no drum to belt contact.

That could certainly be my problem, not leaving a gap between wraps...

Thanks Michael!!

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"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

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Happy to be able to contribute!

Filippo, nice addition of the digital caliper there!!!!!!

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

Michael,

Do you mean you leave 1/8" between wraps across the whole length of the drum or just the final wrap before it goes into the tensioner on the motor side of the drum?

Regards,
Steve.

Between each wrap..

Cheers, M

I use some double stick tape at the beginning and end of the roll where the drum roll attaches to the sandpaper. It helps keep a ridge from sanding into the wood. Aslo, I attended a work shop with Kent Everett last year. He uses velcro to attach the roll to the drum.

R

Michael,

Thanks! That's certainly something new to try and not in the Jet manual. It won't fix my issue with belt around the join area but will help.

Regards,
Steve.

Hi Everyone,

just like to say thanks to everyone that responded to my question - it is very much appreciated! One of the great things about being a member of a forum like this is how willing people are to offer their knowledge and experience to help someone with a problem. Awesome!

As someone pointed out (Jeff!), I cross posted this question to other forums and from all the replies it seems that this is common problem with the 16-32's and 22-44's. The most expedient solution seems to be to use a sled and the weight of a 3/4" ply or MDF sled should flatten the conveyor belt at the join line and give a better result.
The only downside I can see to a sled (especially for sides) would be that the use of infeed/outfeed tables would probably be mandatory. I do have these tables but rarely attach them to the sander because of storage/mobility issues.

I have heard of people using poly belts to fix this issue for the 22-44 but they seem hard to source (but are available from Klingspor for the 16-32). Anyone interested in exploring this option might like to read this post from the North Carolina Woodworkers forum for sources(http://www.ncwoodworker.net/forums/showthread.php?t=47013).

My other question(s) is this - I have tensioned my conveyor belt as per Jet manual (enough tension so the belt doesn't slip when you place moderate hand pressure on the infeed side of the conveyor). Are other people tensioning as per the manual or can you put on a little more tension to help "flatten" the bulge around the join line on the conveyor? Any tips from anyone about how to achieve "correct" belt tension? I'm wary of overtensioning and bending my rollers but there seems to be scant info available in the manual about correct tensioning.

Thanks & Regards,
Steve.

My feed belt has got the same hump on either side of the seam. It needs to be replaced.

Regarding belt tension.. I'd think that as long as you aren't causing a bow in the feed or tracking rollers, that you could put a bit more tension on the belt. I'm saying a 1/4-1/2 turn per side. I will say that it's unlikely that the additional tension we get rid of the bump.

M

I've been experimenting with the wrap spacing and feed rates. I was getting gouges, burning, and poor paper life. The gouging had to be caused by the paper trying to climb over the trailing wrap.. Solution.. wider wrap spacing. I also think that the wider gap allows for better dust removal, heat dissipation, and allows the paper tensioner do its job. The other change I made was to increase the feed rate. I'm getting very clean results running 80 grit paper, 45-60 IPM, 1/8 turn of the wheel per pass. I was running at 30 IPM and a 1/4 turn. I ran 4 sets of figured Bubinga yesterday. I had a look at the paper after and it still looked new.

I should mention that I use this tool to rough thickness the stock only. IMO you will never get wide belt results with a tool as primitive as this.

Michael

Oh.. and one more tip if you didn't already know. Run your top and back plates through the sander across the grain until you get closer to your target thickness. The glue won't build up in one lovely stripe on the paper..