Dip in outfeed planer/thicknesser

[YorkshireMartin]

I am probably pushing my luck as all I seem to do is bang on about issues with planer thicknessers....so, at the risk of outstaying my welcome..

After the debacle with the Axminster, I thought I'd go the whole hog and I managed to pick up a used Sedgwick PT255. I figured there wasn't much to go wrong with those. I found a used example from a dealer at a reasonable price. It turned up today and appeared as the vendor described. It's in pretty good nick overall.

The problem is, theres a dip in the outfeed table. I will have to borrow some feeler gauges to check how much of a dip there is, but it's enough that I can see daylight. I know my straight edge is perfectly straight and I verified it just to be sure.

The dip is along the width and is towards the front edge of the table but not across it's entirety. I'm thinking that someone was planing a lot of thinner stock and pulled the fence towards the front, the resulting friction from the thinner stock causing the dip, but surely this would take years? I doubt the machine is over 15 years old, it's in the newer sedgwick colours and the finish looks original.

This was described to me as a machine that had light use and indeed, visually I'd agree, aside from the issue above. I don't think it's been cosmetically restored.

How much of a dip should I tolerate? I don't want to cause a fuss if I'm close enough for it not to matter. I will be using this for traditional joinery though.

I'm not having much luck with planer/thicknessers at all!

Thanks again everyone, I promise I'll eventually start answering some questions, just as soon as I have some knowledge.

 

[blackrodd]

Doesn't sound wildly serious judging so far, Some pics and measurement details would help myself and others
To give their opinion.
Regards Rodders

 

[Beau]

Any chance that it's not fixed down evenly? If so a few strategic shims might save the day. Not familiar with the Sedgwick so could be talking nonsense

 

[YorkshireMartin]

Doesn't sound wildly serious judging so far, Some pics and measurement details would help myself and others
To give their opinion.
Regards Rodders

Cheers Rodders. I'll get my hands on some feeler gauges over the weekend and measure the dip.

 

[YorkshireMartin]

Any chance that it's not fixed down evenly? If so a few strategic shims might save the day. Not familiar with the Sedgwick so could be talking nonsense

Not really my friend. The dip, when viewed from the table end, looks like ----u-- if you see what I mean. It's not an alignment issue, the fence is perfectly square to the table and the infeed table is perfectly flat.

 

[blackrodd]

Doesn't sound wildly serious judging so far, Some pics and measurement details would help myself and others
To give their opinion.
Regards Rodders

Cheers Rodders. I'll get my hands on some feeler gauges over the weekend and measure the dip.

And also you said that the whole bed wifth isn't affected, just one area, so if you could detail, or sketch that would be
helpful,
Regards Rodders

 

[YorkshireMartin]

Any chance that it's not fixed down evenly? If so a few strategic shims might save the day. Not familiar with the Sedgwick so could be talking nonsense

Not really my friend. The dip, when viewed from the table end, looks like ----u-- if you see what I mean. It's not an alignment issue, the fence is perfectly square to the table and the infeed table is perfectly flat.

Rodders.

If you take the - as the flat part of the table and a u as the dip. Viewed from the end of the outfeed table it looks like ----u--

It isn't central, which is what made me think that the fence has been used in a far forward position. Am I making any sense?

I'll get pics and measurements. I just wasnt sure if there was a rule of thumb for this or not.

 

[blackrodd]

Is it this one, or the newer version?
Rodders

https://nigeldavidbrown.wordpress.com/2 ... 5-rebuild/

 

[YorkshireMartin]

Is it this one, or the newer version?
Rodders

https://nigeldavidbrown.wordpress.com/2 ... 5-rebuild/

The newer version. Logo is printed white over navy blue. I'd say circa 1995 on.

 

[RobinBHM]

Unfortunately all too common with cast iron. Its a bit like timber; ie it can warp!

The metalworkers on here may correct me, but I believe cast iron parts are often left for quite a few months before final machining to allow any warping to happen.

I would set the machine up well: hone the blades, adjust height of blades to just above outfeed table, calibrate fence squareness. When happy, run out some samples and see if the results are good. You may find that you just need to keep the fence away from the problem area for edging.

Sedgewick machines are solid, well built machines, Im sure this wont spoil youre enjoyment of using the machine.

I once had a multico surface planer with a slightly bowed top. To get rid of it, I used a belt sander, a straight edge and feeler gauges. It wotked, but took an awful long time.

 

[YorkshireMartin]

Unfortunately all too common with cast iron. Its a bit like timber; ie it can warp!

The metalworkers on here may correct me, but I believe cast iron parts are often left for quite a few months before final machining to allow any warping to happen.

I would set the machine up well: hone the blades, adjust height of blades to just above outfeed table, calibrate fence squareness. When happy, run out some samples and see if the results are good. You may find that you just need to keep the fence away from the problem area for edging.

Sedgewick machines are solid, well built machines, Im sure this wont spoil youre enjoyment of using the machine.

I once had a multico surface planer with a slightly bowed top. To get rid of it, I used a belt sander, a straight edge and feeler gauges. It wotked, but took an awful long time.

Can warp occurr even if the dip isn't all the way to either edge Robin?

Many thanks.

 

[heimlaga]

It is possible to wear a dip in a cast iron table but it takes a lot of use. I duobt it could develop in less than 30 years even if the machine works 10 hours a day six days a week. A worn dip is easy to recognise as there are no machining marks at the lowest point.

I think the cast iron has warped after machining. That is a common occurance on cheap stuff that was machined only days or weeks after casting. On good qualitry machines like a Sedgwick the cast iron is (or at least should be) seasoned for quite a while before machining but in a few rare instances it may warp a bit after machining none the less.
There is a very slight bump in the infeed table of my Stenberg combination. Right in the middle while both edges are straight. I haven't bothered to scrape it flat because the bump is too small to do any harm in practise.

 

[YorkshireMartin]

It is possible to wear a dip in a cast iron table but it takes a lot of use. I duobt it could develop in less than 30 years even if the machine works 10 hours a day six days a week. A worn dip is easy to recognise as there are no machining marks at the lowest point.

I think the cast iron has warped after machining. That is a common occurance on cheap stuff that was machined only days or weeks after casting. On good qualitry machines like a Sedgwick the cast iron is (or at least should be) seasoned for quite a while before machining but in a few rare instances it may warp a bit after machining none the less.
There is a very slight bump in the infeed table of my Stenberg combination. Right in the middle while both edges are straight. I haven't bothered to scrape it flat because the bump is too small to do any harm in practise.

Very good points.

I need to take a closer look. The table has lines on it which I presume are some kind of anti-friction finish.

Will definitely post back with good photo's and measurements.

Thanks everyone. I really do appreciate this.

 

[Benchwayze]

Martin,


My Sedgwick 12" is in dire straits at the moment, due to a flood from my water tank. So it isn't running at all!

However, it has had a slight dip in the out-feed and in-feed tables for close on 20 years. I've never noticed that it affected the accuracy of squaring up timber, preparatory to thicknessing. I don't know why not, as one would expect a problem. But truth is, it doesn't give me any grief. I'd suggest you 'suck-it-and-see', as they say. If you find that you can't get two sides at a true 90 degrees, then you probably know where to start looking.

If as you say, the in-feed is flat, then this shouldn't affect your results. By the time the timber reaches the out-feed, machining is finished, so you really just need to make sure you have good contact between the in-feed table and the fence, which as you say is at true 90. Maybe that's why mine never gives trouble, because I do use the extremities of the cutters when straightening narrow edges. :wink:


I hope that helps.

Cheers

 

[dzj]

If it was because of wear, I imagine that both tables would have such a dip.
As already mentioned, hone the blades, set everything up and give it a try.
It'll probably work fine.

 

[custard]

The problem is, theres a dip in the outfeed table. I will have to borrow some feeler gauges to check how much of a dip there is, but it's enough that I can see daylight. I know my straight edge is perfectly straight and I verified it just to be sure.

How much of a dip should I tolerate?

I think from memory that Felder tables are guaranteed flat to +/- 0.1mm. That's about 4 thou. I believe that with backlighting you can clearly perceive a gap down to slightly less than half a thou.

I don't want to sound rude but I'm sceptical about your confidence in your straight edge. Three reasons for that. First, it seems odd that someone without feeler gauges would have an excellent straight edge. Second, how did you verify it? Quantified verification requires fairly sophisticated kit, how does someone without multiple straight edges or even feeler gauges verify a straight edge? Third, the DIN standards for a (non inspection grade) straight edge would, across a metre length, just permit visible light when backlit.

But in any event, all this amateur metrology is probably wasted effort. The better route, as previously recommended, is to invest your time in honing and setting the blades, then run some timber through the machine and see if you're happy with the results.

Good luck!

 

[YorkshireMartin]

The problem is, theres a dip in the outfeed table. I will have to borrow some feeler gauges to check how much of a dip there is, but it's enough that I can see daylight. I know my straight edge is perfectly straight and I verified it just to be sure.

How much of a dip should I tolerate?

I think from memory that Felder tables are guaranteed flat to +/- 0.1mm. That's about 4 thou. I believe that with backlighting you can clearly perceive a gap down to slightly less than half a thou.

I don't want to sound rude but I'm sceptical about your confidence in your straight edge. Three reasons for that. First, it seems odd that someone without feeler gauges would have an excellent straight edge. Second, how did you verify it? Quantified verification requires fairly sophisticated kit, how does someone without multiple straight edges or even feeler gauges verify a straight edge? Third, the DIN standards for a (non inspection grade) straight edge would, across a metre length, just permit visible light when backlit.

But in any event, all this amateur metrology is probably wasted effort. The better route, as previously recommended, is to invest your time in honing and setting the blades, then run some timber through the machine and see if you're happy with the results.

Good luck!

Hi everyone and thanks for the support/ideas.

Just to address your points above custard. I'm just setting up so am in the process of acquiring (quality) tools. The straight edge is a brand new Starrett, so I was pretty sure it's straight and I did check it on the beds of the other planer I have here which were completely flat, hence the confidence in it. Hadn't got around to buying any feeler gauges which as it turns out is just as well, as my Dad gave me a set today that I didn't even know he had.

The end result is that the dip is 0.1mm, which is absolutely fine. I'm guessing the movement of wood would far exceed this. It wasn't caused by wear, so must be a slight warping following machining. The rest of the machine is perfectly square as far as I can tell and the fence, as you'd expect, is solid as a rock.

So all in all, a relief. Now all I need is a visit from the electrician and I can rock and roll. Only two months behind my original schedule for my first project...!

Thank you to everyone who helped out. It really is appreciated, especially by someone new to the subject like myself.

 

[blackrodd]

Is that 4 thou? As the peeps have said, Whist it's crucial that both the infeed and outfeed beds are parallel to each other for sucessful timber straightening, in this case that is not any concern over such a small area,
At least you know you're latest "recruit" will be up to any jobs you have planned, and you've not wasted the money outlaid in the acquisition.
Regards Rodders

 

[YorkshireMartin]

Is that 4 thou? As the peeps have said, Whist it's crucial that both the infeed and outfeed beds are parallel to each other for sucessful timber straightening, in this case that is not any concern over such a small area,
At least you know you're latest "recruit" will be up to any jobs you have planned, and you've not wasted the money outlaid in the acquisition.
Regards Rodders

Hi Rodders,

Yep 4 thou, or just under. Not going to get my pink frilly knickers in a twist over that.

Co-planar surfaces are essential yes. All sorted on that front I think.

Need to try it. I'm so excited, bit like a schoolboy. Wish the electrician would hurry up!

 

[Adam9453]

Yep 0.1mm is near as dammit 4 thou.
Moral of this story, I'm afraid, is don't go looking for problems.
Use a machine or tool and only if you find a problem do you need to solve it.
This is not meant to sound harsh but you'll never get around to making anything if you don't get on with using the machines rather than inspecting them.