Restoring cast iron P/T beds.

[Froggy]

Hi everyone, The thicknesser bed on my Kity PT is cast iron with a black coating over the cast which reduces friction ( a bit like teflon). However the coating is coming off the centre of the bed which is now very rough and creating gouges in my wood. I would like to sand it and recoat it. Is this possible and if so what is the coating called and where do I get it?

T.I.A. Froggy.

 

[yetloh]

I think you may find that the bed is in fact aluminium. Certainly, that was the case with the Kity 613 bandsaw I used to have. It had a dark grey coating of some sort which sounds similar to your p/t. I'm afraid I don't have a solution but given the propensity for aluminium to wear I do think it would be a good idea to repair or refinish it. I am sure someone will have some ideas for a finish which be very hard wearing and suitable for use on aluminium.

Jim

 

[Froggy]

Hi Jim, Mines a Kity 1637 but I'm sure you're right - it may well be aliminum the same as yours. I have cleaned it and sprayed it with a silicon spray which helps smooth things for a short while, but the aliminum is getting so rough now I really have to rub it down. But without the right protection, I'm worried this will make things worse.

 

[Steve Maskery]

Kitys are aluminium and are vulnerable to damage, particularly the thicknessing bed if you try to thickness timber that has not been planed. A friend of mine brought round some timber and I made the mistake of assuming he knew what he was doing. He wrecked the bed.

The best thing I can recommend is to use a fine flat file to remove any high burrs from where the ali has been ploughed up, then rub with a finishing wax.

Cheers
Steve

 

[Froggy]

Hi Steve, I had a feeling you might reply - I know you've got the same PT. Ithink I may have done the damage when I did a bit of skip planing with unplaned wood. So my own fault, and lesson learnt. You'd use a flat file rather than sandpaper?

 

[Steve Maskery]

Yes. You want to cause as little damage to the bed as possible, removing only the high spots and not touching the rest of the bed.
If you have BIG voids in the surface, I guess you could fill them with car body filler and then a good waxing, but I've never tried that and I have no idea how effective it would be. It might just make matters worse. Anyway, it's not the voids that do the damage, its the high ridges that scratch the wood.
S

 

[Froggy]

OK I'll give that a go Steve, thanks.

 

[katellwood]

This may appear a bit radical but have you considered some sort of permanent fix.

I would bolt a piece of 1/4 plate the same size of the bed, to the bed with countersunk bolts, Ok you will lose 6mm in the depth you can thickness and have to reset the measurement gauge but I feel will solve the problem of the ali wearing away permanently and allow unplaned timber to be thicknessed

thoughts please

 

[katellwood]

found this photo of a kity 1637 thicknesser bed

it appears that the height is adjusted by four threaded bars as opposed to a central column. therefore it would be easy to bolt some sort of new hard wearing bed to the existing aluminium. The only issue that I can see are the raised edges on the aluminium which prevents the timber being put through fouling the height bars. either something would need to be attached to the sides of the false bed to mirror the original or care must be taken when timber is fed through

That being said this would be a permanent fix with minimal loss of depth and much more hard wearing that the original aluminium

 

[Steve Maskery]

If you wanted to try out a non-permanent fix:

Take a piece of MDF the width of the bed and 40mm longer
Face it with Formica and wax it
Glue two 20mm battens to the underside, one at each end
Drop the new bed over the original
See how well it works.

S

 

[Racers]

Hi,

I have a Bestcombi 2000 which has nearly the same planer/thicknesser. I guess the ideal way would be to have the bed skimed at an engneering company then re-anodised, don't know how much it would cost.

Pete

 

[Froggy]

Hi everyone,

I have considered a permanent fix or even just buying another bed and replacing it, but I'm worried that I may not get it back together with the same accuracy I have now if I take it apart!! I'll try the filing and waxing first and if that doesn't work I'll consider all of the above permanent fixes. Have any of you taken a thicknesser bed off before, and if so was it a tricky job or not? Thanks for help everyone.