Sedgwick MB rise and fall damage

[jetsetwilly]

Morning all, inspired partly by the excellent refurb thread from @deema and @Sideways, I have acquired a Sedgwick MB in green, but I think I've already broken it getting it home. It was slung under the thicknesser table as per the manual, with a block of wood jammed between thicknesser table and rollers/cutterblock, but after it was loaded I noticed that the wood was actually on the fingers, and now the thicknesser table falls nicely but when lifting it sticks, seemingly once per handle revolution. I can't see any damage from underneath, but clearly there is some.

My question is where is it likely to be? I can't see how a pull on the table could stress the worm gears (as the acme rise/fall thread should not transfer any force to them), but I also can't see how it could be anything else.

I hadn't planned it, but looks like I might be doing my own stripdown thread....

 

[jetsetwilly]

Whipped the rise/fall threaded block out. Thread looks mullered to me…. I guess the next step is to find a machine shop, but are there any other suggestions?

 

[johnnyb]

Helicoil

 

[jetsetwilly]

Yebbut I think it's a special thread...

 

[Amplidyne]

Let's have a look at the male thread. Give us some more idea of what sort of thread it is, and it the thread is indeed deaded.

 

[Housey210]

Morning all, inspired partly by the excellent refurb thread from @deema and @Sideways, I have acquired a Sedgwick MB in green, but I think I've already broken it getting it home. It was slung under the thicknesser table as per the manual, with a block of wood jammed between thicknesser table and rollers/cutterblock, but after it was loaded I noticed that the wood was actually on the fingers, and now the thicknesser table falls nicely but when lifting it sticks, seemingly once per handle revolution. I can't see any damage from underneath, but clearly there is some.

My question is where is it likely to be? I can't see how a pull on the table could stress the worm gears (as the acme rise/fall thread should not transfer any force to them), but I also can't see how it could be anything else.

I hadn't planned it, but looks like I might be doing my own stripdown thread

 

[Housey210]

Morning all, inspired partly by the excellent refurb thread from @deema and @Sideways, I have acquired a Sedgwick MB in green, but I think I've already broken it getting it home. It was slung under the thicknesser table as per the manual, with a block of wood jammed between thicknesser table and rollers/cutterblock, but after it was loaded I noticed that the wood was actually on the fingers, and now the thicknesser table falls nicely but when lifting it sticks, seemingly once per handle revolution. I can't see any damage from underneath, but clearly there is some.

My question is where is it likely to be? I can't see how a pull on the table could stress the worm gears (as the acme rise/fall thread should not transfer any force to them), but I also can't see how it could be anything else.

I hadn't planned it, but looks like I might be doing my own stripdown thread....

Get a screw pitch gauge, cheap enough. Measure hole, my guess M16, and get a tap

 

[jetsetwilly]

Get a screw pitch gauge, cheap enough. Measure hole, my guess M16, and get a tap

Are the old Sedgwicks metric? Can't find my thread gauges but with a dial gauge it's possibly M20x2.5 (seems too big for 3/4-10). I thought it was trapezoidal but actually looks like a plain thread, in which case a tap might be worth a try, though to me it looks like a fair bit of material has gone.

The male thread is fine, I'm guessing it's hardened steel.

 

[toolsntat]

Are the old Sedgwicks metric? Can't find my thread gauges but with a dial gauge it's possibly M20x2.5 (seems too big for 3/4-10). I thought it was trapezoidal but actually looks like a plain thread, in which case a tap might be worth a try, though to me it looks like a fair bit of material has gone.

The male thread is fine, I'm guessing it's hardened steel.

I wouldn't be so sure about that thread being ok, it looks "rolled" over to me?
Cheers Andy