Drum sander project started.

[Lons]

I decided i couldn't give Axminster £750 for a new jet 10-20 :roll: so nothing else for it but to get my old bones out of the chair and make one.

Many youtube videos and a few scribbled sketches and a few hours work results in some progress using stuff from my piles of treasured items. I'm making it up as I go along tbh but can't see why it won't work. Parts are semi finished so quite a lot to clean up before varnishing the ply.

A couple of self centering bearings, 5/8" steel rod, old 1ph motor, 25mm ply, 22mm melamine faced board, some 6mm inserts, ( I drilled 3 hinge points at the back with inserts on back of ply sides and in the edge of the table. Fitted in the centre hole but dropping down will allow up to 130mm thick material ). Intend to make the drum from 110mm pvc soil pipe but will support well into the ends and stepped ends with turned ply, mdf ?. Only has a width capacity of around 350mm as was limited by the length of shaft I have but will have to be enough!
I'll make up a mechanism to raise and lower the table front probably with side guides through routed groove so I can lock it off and later decide whether to make up some kind of infeed roller. Dust hood most likely out of ply and polycarbonate.

My first idea was to make the feed table from 25mm Mistral solid surface but then found the melamine board which is dense and heavy.

Any ideas or thoughts are most welcome btw
I don't expect rapid progress because I'm known to procrastinate so this could take a long, long time. Cr*p pics from phone.

Bob

 

[Honest John]

After much soul searching, talking myself out of it several times, after several visits to Axminster Warrington I might say, I eventually succumbed to my desires and bought the damn thing just after the brexit result when Jet prices shot up about 10%. Should have done it earlier I thought. Delaying cost me 10% I thought. Damn damn I thought. Then I got it home. This is brilliant I thought. Then 2 days later I decided I'd have a run out to Turners Retreat to their autumn show. The first thing I came across was a nice man on a Jet stand selling a range of their machines. The star of his mans display was the 10-20 Drum sander, including the stand, for about £250 less than I paid to Axminster (without the stand) only 2 days earlier! Oh dear I thought..... words to that effect. When I was looking for one I couldn't find anyone selling them for a price different from the Axminster price. Indeed it sniffed of a price fixing arrangement.
I've put it behind me now. It doesn't affect me much now. I've started sleeping again and the blood pressure is more or less under control. On the positive side, the machine is all I expected of it, and gets used most days when I'm in my shop.

 

[xiphidius]

Nice one Lons ...following with interest but as you say I may have to shave a few times in-between lol...All the best with the project and good luck with the results..
BTW where did you get the bearings and the rod from, what is the dia of the shaft and what will you use to connect the motor to the shaft...suriosity killed the cat lol
Regards
C

 

[curtisrider]

Watching this with interest as I want to build one in the near future!

 

[Lons]

Nice one Lons ...following with interest but as you say I may have to shave a few times in-between lol...All the best with the project and good luck with the results..
BTW where did you get the bearings and the rod from, what is the dia of the shaft and what will you use to connect the motor to the shaft...suriosity killed the cat lol
Regards
C

Can't remember where I got the "goodies" as I've had them for a long time but if you google bearing blocks or plumber blocks they're easily available with different bores so you can match up with what you have or buy both from scratch.

These are 5'8" and luckily I had a length of steel the same dia to use as a shaft. The old 1ph motor happens to be 5/8" as well though that wouldn't matter. It's a 1425 rpm so I need to work out best speed for the drum and sort out correct size pulleys to suit - haven't got that far yet. Will just use standard V pulleys and belt and will mount the motor under to suit.

Build so far is dead easy tbh, would be even easier if I'd just hinged at the back with door hinges but the 6mm bolts / inserts work really well and give me the option of relocating the feed table if I want so it's not at a steep angle when thicknessing thin stock. Well that's the theory anyway. :lol:

My thinking behind the drum is firstly I have a length of soil pipe already, it looks a great surface and 110mm seems enough and it should hopefully be more durable than the usual MDF drum. I'll need to make sure it's balanced and might well have to make a full MDF roller to fit inside the pipe to give it some mass - don't know yet.

I wouldn't bother shaving while watching progress btw, just grow a beard. :wink:

Bob

 

[sploo]

Watching with interest as this is on my TODO list too.

Some thoughts from having researched others' builds: 5/8" rod may be a bit small (leading to sag or whip). 1" or 25mm seems to be a good choice.

The plastic pipe may not be as round as you'd need. Generally people seem to make the drum from a stack of MDF or plywood discs, then put a sheet of coarse paper on their table and slowly raise it into the drum in order to sand it perfectly round (and true to the table).

 

[xiphidius]

On the bore of the rod would it would it not make sense to buy a bobbin sander core or cores then you can get the belts easily and buy a rod to suit the dia. of these sleeves.???? Even if not heavy duty attach a drill instead of a motor...just sayin like lol

 

[Lons]

Watching with interest as this is on my TODO list too.

Some thoughts from having researched others' builds: 5/8" rod may be a bit small (leading to sag or whip). 1" or 25mm seems to be a good choice.

The plastic pipe may not be as round as you'd need. Generally people seem to make the drum from a stack of MDF or plywood discs, then put a sheet of coarse paper on their table and slowly raise it into the drum in order to sand it perfectly round (and true to the table).

Thanks, all comments and suggestions welcome, it keeps the grey matter working and might save me some expensive mistakes.

Time will tell, but the whole point really is to make it out of as much as I have already rather than buy then if it's disappointing there's little lost and I've learned along the way.

I already had both the 5/8" bar and bearings to suit so guess I saved maybe £50 or £60 and the bar is over that short length, almost impossible to bend. If I was buying all from scratch then thicker shaft and bearings to suit would always be a good idea.

From what I read and watched plywood can vary and be unbalanced so as you say MDF is favourite however it also seems that MDF doesn't stay true and has to be trued up occasionally. I've just been out and checked the pipe by drawing a circle around it and checking that with a compass and it seems perfectly round to me but my idea was to form an MDF drum anyway to give some mass, I would do that on the lathe, leave it fractionally oversize for the inside of the pipe and follow the youtube videos to do as you say to true it to the table so the pipe will be a tight fit over. There is enough pipe wall thickness to skim a fraction off if nec. What I have already done is ensure the shaft is exactly parallel with the table so I don't see a problem that I can't solve.

I was looking for something to adapt for the rise and fall mechanism and found the perfect thing, a 12" G clamp but couldn't bring myself to destroy it so I guess I'll be buying some threaded rod and nuts. I have some bits that are too short. but even I'm not mean enough to weld it together #-o :lol:

On the bore of the rod would it would it not make sense to buy a bobbin sander core or cores then you can get the belts easily and buy a rod to suit the dia. of these sleeves.???? Even if not heavy duty attach a drill instead of a motor...just sayin like lol

Not something that had crossed my mind. :-k
Everything I've looked at uses rolls of abrasive fitted at an angle and secured both ends and I've found 5 and 10 metre rolls on the internet at cheap prices so has to be the way to go. Also would mean having to take off the drum to change abrasive, can yo get sleeves 360 long btw?
As I already have a HD induction 1 hp motor doing nothing I can't see anything else to beat that, especially when it's so quiet as well.

Rough sketch of drum detail as I see it but still evolving, sketch not quite accurate as intention is for the h/w to be stepped to the inside of the pipe for additional support.

 

[mayo.mick]

Following with interest

 

[sploo]

I'm not sure the sander bobbin sleeves would work well - it's likely they'd slip. Usually they're tightened by squeezing the bobbin across its length, and that would be hard (to do evenly) across a longer run and/or multiple bobbins and sleeves.

Re 5/8" rod; the short length may be OK. I'd be worried about whip though (like when you have a thin spindle on the lathe).

Filling the pipe with MDF for mass poses an interesting question; if I were to make a sander I'd definitely go with a heavy MDF or ply drum, but then the commercial machines seem to have relatively lightweight extruded (hollow) sections that I assume are made from aluminium. Not something a DIYer could replicate, but it's interesting that they don't go for mass. No idea why though.

 

[Lons]

I'm not sure the sander bobbin sleeves would work well - it's likely they'd slip. Usually they're tightened by squeezing the bobbin across its length, and that would be hard (to do evenly) across a longer run and/or multiple bobbins and sleeves.

Re 5/8" rod; the short length may be OK. I'd be worried about whip though (like when you have a thin spindle on the lathe).

Filling the pipe with MDF for mass poses an interesting question; if I were to make a sander I'd definitely go with a heavy MDF or ply drum, but then the commercial machines seem to have relatively lightweight extruded (hollow) sections that I assume are made from aluminium. Not something a DIYer could replicate, but it's interesting that they don't go for mass. No idea why though.

I have another length of 5/8 bar just a little shorter and this morning I stuck the end in a metal vice and tried to bend it by pushing, it never moved and I'm pretty sure it's just mild steel so it's worth the risk I think, time will tell. If it doesn't work I'mm reclaim the bits and build a better one or put my hand in my pocket and pay what seems a hefty price for the Jet. Not sure if whip would be an issue as it will revolve at relatively low speed, don't know though so good point.

As a former builder I used pvc soil pipe and it's pretty rigid stuff which is why I'm prepared to give it a go, I could always make up a new drum from mdf if it doesn't.
I guess lightweight aluminium is rigid enough and it's a cost factor but surely a heavier drum, if balanced is better? Again I don't know.

I did see a flaw in mine today #-o The idea of three hinge positions won't work as although I drilled very accurately I can't be sure that moving the hinge won't put the table out of parallel with the drum so it will end as one fixed position - might as well have used door hinges. :roll:

EDIT:
Just thinking a bit more about possible "whip" forces. I don't think it will matter as the shaft will be supported along its whole length by the mass of the mdf so all the force would be concentrated where the shaft goes through the ply and into the bearings, or am I wrong on that? Certainly would be disappointed if the machine shakes itself to bits.

 

[transatlantic]

I think most DIY'ers go for a soild MDF or Plywood drum as it's easy to true up. You can't really true up PVC pipe, at least not by much.

If you went with Aluminium tubing, you could get a thick gauge which would give you something to true, but how would you secure the rod?

 

[Walney Col]

MDF discs on a 5/8" mild steel bar running in pillow blocks will be plenty rigid enough, plus (being solid) it would be a doddle to balance the drum should it need it.

Col.

 

[Lons]

I think most DIY'ers go for a soild MDF or Plywood drum as it's easy to true up. You can't really true up PVC pipe, at least not by much.

If you went with Aluminium tubing, you could get a thick gauge which would give you something to true, but how would you secure the rod?

I actually have a bit of 6mm walled ali tube but the dia is only 60mm so no good.

I covered my thinking on trueing up the drum in an earlier post and because I'll be truing the mdf inner core first as well as being very accurate setting out initially I can overcome that I think, or not perhaps. If the core is accurate then the pipe fitting over it should be as well :lol: The pipe has about 3mm wall thickness so room for a little if I have to however I think the reason for wide use of mdf is down to other things as well and I hope my drum will be more accurate before truing on the sander than some of the ones I've seen on youtube.

I'm going to have egg on my face if this doesn't work, won't be the first time! :lol:

 

[sploo]

I think most DIY'ers go for a soild MDF or Plywood drum as it's easy to true up. You can't really true up PVC pipe, at least not by much.

If you went with Aluminium tubing, you could get a thick gauge which would give you something to true, but how would you secure the rod?

I actually have a bit of 6mm walled ali tube but the dia is only 60mm so no good.

I covered my thinking on trueing up the drum in an earlier post and because I'll be truing the mdf inner core first as well as being very accurate setting out initially I can overcome that I think, or not perhaps. If the core is accurate then the pipe fitting over it should be as well :lol: The pipe has about 3mm wall thickness so room for a little if I have to however I think the reason for wide use of mdf is down to other things as well and I hope my drum will be more accurate before truing on the sander than some of the ones I've seen on youtube.

I'm going to have egg on my face if this doesn't work, won't be the first time! :lol:

Can't help thinking that, if you're going to the effort of making the MDF discs, then what's gained by using the soil pipe? As transatlantic notes, truing up the PVC pipe may be difficult; whereas sandpaper on the table under the MDF discs should work well.

As for issues with the 5/8" rod: I'd forgotten you were "only" going with ~360mm length. That's shorter than what I've seen from those that had problems with the smaller rod (i.e. you may well be OK).

 

[Lons]

Can't help thinking that, if you're going to the effort of making the MDF discs, then what's gained by using the soil pipe? As transatlantic notes, truing up the PVC pipe may be difficult; whereas sandpaper on the table under the MDF discs should work well.
As for issues with the 5/8" rod: I'd forgotten you were "only" going with ~360mm length. That's shorter than what I've seen from those that had problems with the smaller rod (i.e. you may well be OK).

Hi Sploo, because the pipe is smooth and durable compared to mdf and seems it might be better to me. If I'm not happy with it then worst scenario as I see it is I remove the pipe and true the hardwood ends, ( about 20mm wide each side) and I still have an mdf drum only a few mm less in dia. Ok a bit more effort initially but could be the bees knees or a sows ear, don't know until I try.

On a different aspect, I don't care for the usual method of a threaded bar just resting on a metal plate under the feed table as I feel it could slip and allow the table to move although I am planning a fixing each side through slots in the ply sides. My thoughts at the minute are to drill and tap a length of larger bar to make a tubular nut to fix to the base in a slot allowing movement front to back to accommodate the very slight curve as the table is lifted. Top of rod would have threads removed and be held captive through a fixed plate by washers and split pins though I'd need to make it a good fit to avoid slop.
I might do a quick sketch later for opinions as just in my head at the minute. The max thickness of threaded rod I have in stock is 10mm which probably isn't sturdy enough so if no obvious design flaws I'll mock it up and if works will buy some 20mm (if I have a tap) or might even sacrifice that G clamp. :-k

cheers Bob

 

[Lons]

MDF discs on a 5/8" mild steel bar running in pillow blocks will be plenty rigid enough, plus (being solid) it would be a doddle to balance the drum should it need it.

Col.

That's what I'm hoping Col but the proof is in the puuding.

 

[Lons]

OK these are my thoughts on a possible rise and fall arrangement.

Any thoughts, will it work, is it over complicated?

edit: Think a single central bearing point on the feed table isn't clever so maybe use a length of steel angle along the front edge instead of just a plate, or is that overkill?

 

[sploo]

Understood on the pipe - it'll be interesting to see how it goes.

Agreed on the rise and fall mechanism - I've often thought the same with other DIY builds I've seen. Some designs have arced slots in the sides of the frame, and bolts with knobs going through the slots into the sides of the table - once the height is set you tighten the table with the knobs (so the slightly floppy rise and fall mechanism isn't such a problem).

Your design looks good - though I guess the top washer and split pin system would have to have really tight tolerances, as if it can move by 0.1mm that's probably about the depth of pass on a sander anyway. It reminds me somewhat of one of these: http://barn-door-tracker.co.uk/

Most of the modern open sided machines have a single threaded rod that lifts the whole motor and drum assembly (table is fixed) but I think that'd be hard to DIY with sufficiently quality.

 

[Lons]

Yep my intention is to slot the sides and make up 6mm threaded rod with turned knobs to lock the table. What I was going to do was tape a pencil to the feed table and raise it to mark a piece of thin card, transfer that to mdf, cut out on scrollsaw to make template for router guide and cut the slots. Bet there's an easier way I don't know about. #-o

I have a couple of ideas on eliminating play at the top of the rod but need to try out.

Thanks for the link, I've never seen a barn door tracker, very interesting. It's only a few months since we were at the Kielder Observatory and saw the telescopes, a bit more sophisticated though.