Red Gum slab issues

[Luckypierre]

Hi,
Have started to sand a red gum slab for a kitchen breaky bar. The slab is 2100mm by 900mm and 60 mm thick. It has a bit of a dip in it; say 10 mm warp into the centre. I plan to level / flatten the slab but the belt sander is hardly making a dint and the going is hard yakka. I am using 40grit paper at present.
How would an electric planer handle a red gum slab?

I welcome any suggestions.

Pete:banghead:

[simon d]

hello Pete. I am a newby too but i have had a little experience with planeing red gum. It has a complicated cross hatch grain with tends to chip out whichever direction you follow the grain. I have had a bit of success levelling with a hand plane but sanding is the only way to finish it smoothly. An electric plane will always leave a square gouge which has to be sanded out so i don't recommend using one
I recommend setting a bench plane to as shallow a cut a possible and using a bow ground blade and winding sticks to sight the level. cut perpendicular to the grain in short passes with a firm lift at the end of each stroke. When your winding sticks say its pretty flat then use a really course grit on your belt sander also perpendicular to the grain. When that's done and flat now turn the sander to follow the grain.
Then a medium grit along the grain and then a fine grit. Don't use an orbital sander if you can avoid it as even fine grit will leave scratches in the really hard surface.
happy sanding. Oh and keep the sanding dust in a tin to use as a glued filler for any chips, splits and holes.

[Expat]

Years ago I had a red gum slab that had pretty much the same problem. I wound up fixing it in three stages. First I set up a jig for my router to run on and used it to level the entire surface of the slab. Then I went at the now level surface with various grades of paper in a belt sander. Finished it with a ros down to 1000 grade. It took a bloody long time but once it was ready for a finish it was smooth as a baby's bum!

[Hafgan]

Just a newbie here, but my short experience with redgum has taught me:

You are going to be going for a hell of a long time to flatten it with a handplane, and an electric plane will be too uneven
Although it will cost, perhaps look at discussing the issue with your local woodworkers - from memory, there are a few in Bungendore :;!!
Alternatively, contact a timber retailer and they may have a thicknesser that can dress it down evenly - as long as one side is flat!
Otherwise, if you want to do it yourself, the plan above to use a jig and router to slowly bring it down would work. Slowly.

My 2c worth.

Hafgan

[Luckypierre]

Years ago I had a red gum slab that had pretty much the same problem. I wound up fixing it in three stages. First I set up a jig for my router to run on and used it to level the entire surface of the slab. Then I went at the now level surface with various grades of paper in a belt sander. Finished it with a ros down to 1000 grade. It took a bloody long time but once it was ready for a finish it was smooth as a baby's bum!

I may have to invest in a router. Never used one (I know!....its 2009), just never needed to as my house has very little timber (termite central).
How did you 'set up' the jig? What sort of a router bit should I buy?

[Lignin]

Pierre,
You're not a million miles from Moss Vale where there is a company that has gigantic drum sanders.They usually flatten compressed fibrous cement or some such, but studenta from Sturt School of Wood at Frensham in Mittagong, go there to get larger work pieces flattened.The cost is very reasonable.:2tsup::2tsup:
Be warned though.They are a sincerely Christian family, and the SLIGHTEST profanity or blasphemy will result in you being shown the door.
Jim:U

[AlexS]

Pierre,
You're not a million miles from Moss Vale where there is a company that has gigantic drum sanders.They usually flatten compressed fibrous cement or some such, but studenta from Sturt School of Wood at Frensham in Mittagong, go there to get larger work pieces flattened.The cost is very reasonable.:2tsup::2tsup:
Be warned though.They are a sincerely Christian family, and the SLIGHTEST profanity or blasphemy will result in you being shown the door.
Jim:U
Yep. Can't remember their name, but they manufacture floorboards and other stuff (not fibrous cement as far as I know). They can do coarse & fine sanding in one pass, up to at least 1200 wide. Price is reasonable.

I've never used it, but have had reports of redgum slabs moving and deforming the rest of the kitchen as they go. Be aware.

[Luckypierre]

I'll call the Bungendore Woodworks tomorrow. I have lots of friends who work the counter.

Failing that...Just over an hour to Moss Vale. Good plan Jim. I have friends up there I can visit also.

Pete

[Luckypierre]

Yep. Can't remember their name, but they manufacture floorboards and other stuff (not fibrous cement as far as I know). They can do coarse & fine sanding in one pass, up to at least 1200 wide. Price is reasonable.

I've never used it, but have had reports of redgum slabs moving and deforming the rest of the kitchen as they go. Be aware.
Alex,
This slab will be set alone as a breakfast bar. It isn't going to be attached to any kitchen cabinets, if it does twist or warp any more it will become a feature (That's what I'll tell the minister of housewives)

Pete

[Luckypierre]

Jim,

Is it Coach House Timbers? Had a look in phone book.

Pete

[Lignin]

Sorry, I don't know the name of the firm, but if you give Sturt a ring they MIGHT be able to help, but the Director is severely unwell, and this year's classes probably haven't started.
Your mates @ Bungendore Wood Gallery might be able to put you in contact with one of the Sturt ex students that exhibit there.:2tsup::2tsup:
Hope this helps,
Jim.
PS, I'm sticking by my claim that the firm DOES work concrete slabs.:p:p

[Expat]

I may have to invest in a router. Never used one (I know!....its 2009), just never needed to as my house has very little timber (termite central). How did you 'set up' the jig? What sort of a router bit should I buy?
Well the jig I built rolled along on the mdf top I secured to the workbench so it was dead level and smooth. That's something you have to be sure of from the get go. I used 4 industrial casters - fixed, not swivelling - to support the frame for the router. This frame bridged the slab and was built so that it barely cleared the slab surface. It was made from 1" formply. A bit of overkill I know but I wanted it to be solid. The router had a 3/4" collet so it would slide from side to side across the frame of the jig using a 2" flat bottom bit I think I got from a friend of my dad's who was a cabinetmaker out Carindale way. What brand it was I honestly don't know. I'm pretty sure if you can't find one listed by any of the major manufacturers there are companies around that will make you a large flat bottom bit. It took me a lot of passes to get the thing level but once the worst of it was done it was a simple matter of changing to a new 1" bit and making a series of very light passes just to give it a finer cut before I laid into it with the belt and then the ros sanders.

ps What's up with the forums today!? Someone do an update or something?

[AlexS]

Don't think it's Coach House timbers- could be Southern Trade Supplies, from memory they are in that area.
Try Sturt - one of the teachers who was helping out last year, James or Stuart, may be able to help if they are around.

Evan Dunstone in Queanbeyan may be able to put you in touch with someone closer who can help you out.

[charlsie]

if you can find someone up your way with a slabmaster they can level the slab for you ,this should take around 30 to 40 minutes then get it put through a good drum sander this way it will be level and flat all up i would charge around $120-$150 the slab should end up around 40mm-45mm thick if you want to go down this track pm me and i'll send you the number for the bloke who makes the slabmaster and he should be able to put you in contact with someone in the local area .all this i think is a lot easier than router jigs and finish sanding (just my opinion)

[Basilg]

The Company is Highlands Timber Coating 02 4869 1488. they have a number of very large drum sanders and can take a slab down to 400 grit if you wish. They do good work, are reasonable with pricing, and are very nice people to deal with.

If you want to get your slab truly flat You will have to start with at least one side reasonably flat, as the drum sander will use one side as a reference surface.
It may be that the moisture balance across the section of the slab is uneven, this can be corrected by wiping the concave side with a cloth soaked in water, which will cause the slab to deflect back, support the slab on timber slats around 25mm thick every 250 mm or so along its length, and monitor the movement of the slab over a period of several days.
Alternatively you could make up a jig using a sheet of 18mm ply, and a series of screws in the ply so the slab will sit level without rocking or flexing under the drums, until the drum sander flattens one side, then you can proceed from there.

Once you have got it flat it is guaranteed to move it is a question of by how much and you will have to build your bar to hold it flat but allow movement across the width.

[jefferson]

I'd suggest that you get someone to make the slab flat with a Wood Wizz. Shame you're not a little closer to Alury Wodonga, otherwise I'd do it for you.

Jeff

[Expat]

iall this i think is a lot easier than router jigs and finish sanding (just my opinion)
Don't I wish I'd had access to such a thing back when I did this. He asked how it can be done and I answered how I did it. That was at least 15-20 years ago so how long has the slabmaster been around?

[Claw Hama]

I do all my wide slabs with a Bosh electric hand planer (hack it down) and then finish off with a Makita belt sander. A slab that size would usually take a couple of hours to get to a reasonable flatness then the usual time to sand a nice finsh. Yes you will get ridges but the closer you get to your finished level the finer you make your cuts, the belt sander should get the rest.

[Luckypierre]

I used to travel to Albury quite regularly to see my son. He now lives here so I don't travel there any more.
Wonder if there's someone with a Wood Wizz near Canberra? Any ideas?

[AlexS]

I used to travel to Albury quite regularly to see my son. He now lives here so I don't travel there any more.
Wonder if there's someone with a Wood Wizz near Canberra? Any ideas?
Ring Wood Wizz, they will tell you who the nearest one is.

[Luckypierre]

I have been in contact with Wood Wizz's Les Owen. There's a chap in Bungendore I am taking the slab to who has a Wood Wizz. $60 an hour to prepare slab.

Thanks everyone, will post result.:)

[charlsie]

not to bag the woodwizz and as i haven't seen a finished product off the machine i'm only going on hearsay.but i was told that on a large slab because the cutter head spins at a very fast rate the cutters tend to knock down and bruise the timber fibres leading to lines being left in the slab.i know a quick pass through a drum sander will fix this but has anybody come across this before? the way it was explained was if you put the slab in a certain light you could see the lines running up and down the slab.and from the way the woodwizz works ie; start from left to right take a cut then right to left the timber is being cut in two different directions.

[MAPLEMAN]

not to bag the woodwizz and as i haven't seen a finished product off the machine i'm only going on hearsay.but i was told that on a large slab because the cutter head spins at a very fast rate the cutters tend to knock down and bruise the timber fibres leading to lines being left in the slab.i know a quick pass through a drum sander will fix this but has anybody come across this before? the way it was explained was if you put the slab in a certain light you could see the lines running up and down the slab.and from the way the woodwizz works ie; start from left to right take a cut then right to left the timber is being cut in two different directions.
When dressing timber with "cranky"grain on a wood wizz or similar equipment,simply keep cutter heads sharp,and dont plane too much timber off at a time! Increments no greater 100mm for example,otherwise you will experience 'tearout".Regards Mapleman:;

[barerlz]

hey mate you should ring around for a local sawmill and ask them if you could put it through their wide belt sander

[AlexS]

not to bag the woodwizz and as i haven't seen a finished product off the machine i'm only going on hearsay.but i was told that on a large slab because the cutter head spins at a very fast rate the cutters tend to knock down and bruise the timber fibres leading to lines being left in the slab.i know a quick pass through a drum sander will fix this but has anybody come across this before? the way it was explained was if you put the slab in a certain light you could see the lines running up and down the slab.and from the way the woodwizz works ie; start from left to right take a cut then right to left the timber is being cut in two different directions.

I bought a slab of mango that Les had done as a demo. It was pretty good, but needed a light plane and sand before finishing.
Here's what I reckon: If the slab's cupped or not very flat, use the woodwhizz, first, then plane or use a ROS depending on how good the finish is.
If the slab's flat and doesn't need much taken off, see the people with a drum sander.