Today's Job...

[parrisw]

Oh Will, you owed me one I guess! :msp_tongue:

The gumboots are for the gumboot throwing competitions! :msp_thumbup:

 

[MCW]

As mentioned earlier I pulled the lid on my modded 390XPG to have a look at what I could do in regard to increasing compression after deciding to sell the 660 and keep this saw. In the process I luckily found a split intake boot so got Brad to order me a new one from the states (thanks Brad ). Anyway, I wrecked the base gasket and thought "Ah well, I'll run it without one".
Unfortunately what I found by doing this was NO squish. The saw could turn over but the piston was "just" tapping the squish band. I finally found enough time yesterday to make it over to my mum and dad's place and sort out a .020" pop up on dad's lathe. Unfortunately his lathe chucks weren't quite deep enough to allow the jaws to fully grab a solid part of the piston. He has an old Hercus lathe from just after WW II.
A winegrape grower that I do work for has a fair setup in his shed (lathe, mill etc) and is an extremely handy and cluey guy when it comes to machining. I rang him this morning and as it was raining here he was doing some work in his shed anyway so he said he'd do it straight away. It took him about 15 minutes, if that. He didn't charge me either! He appreciates my help with Agronomic advice he said - greatly appreciated.
We were aiming for a .020" popup but ended up with a .019" popup - still OK...just

He was also extremely keen to know why the hell I was doing it! I had to talk modded saws for a moment and think I lost him

The most interesting thing was his lathe which I'd seen before but never taken much notice of. It is a solid piece of German equipment and was built in 1956. It's been refurbished though but it very accurate. Over a 600mm shaft he made there was only .00025" runout according to his Mitutoyo guages which isn't too bad in my book

Guys like Nik and other machinists here will probably feel all warm and fuzzy seeing a unit like this still at work - only 4 were ever brought into Australia...

Despite the current digital and electronic age this thing has all the bell's and whistles on it.

When I got home from work I fitted the piston and top end all back together and started the saw - I haven't touched the tune for now but the throttle response is completely different to before and it's noticably harder to pull over. I'm yet to check the compression but it was previously pulling about 150-155psi and I'd hope to see in excess of 180psi now but not sure what to expect. I also went out the shed and buried a 32" bar with 8 pin to the hilt in some very hard wood. It pulled it easily whereas previously it wouldn't have pulled it quite as well. Compression = torque in my book.

 

[Andyshine77]

I love seeing old machines, they just don't make things like that anymore.

The popup looks great Matt, very clean looking work. A popup that size should add a good 10/15 psi, so you will likely see 160/165.

 

[MCW]

I love seeing old machines, they just don't make things like that anymore.

Yeah it's a beautiful piece of equipment mate and you're right, they certainly don't make machines like this anymore. The photos honestly didn't do it justice as they were taken on my phone in a poorly lit shed.

The popup looks great Matt, very clean looking work. A popup that size should add a good 10/15 psi, so you will likely see 160/165.

So what you're saying Andy is that I should have knocked .020" off the cylinder base and made a bigger popup to get 180psi?

 

[Stihlman441]

Ha Matt i cant beleave it thats the same VDF lathe thats in the Geelong Ford Toolroom,i have spent many hours bent over one of those.

 

[MCW]

Ha Matt i cant beleave it thats the same VDF lathe thats in the Geelong Ford Toolroom,i have spent many hours bent over one of those.

Awesome!!! I'll tell this guy that, he'll be stoked! He's got a Chinese 3 jaw chuck on it that he wants to get new jaws for so I emailed a photo of the Chinese writing on it to my Chinese mate to see what he can come up with

 

[Stihlman441]

I dont work up in that area anymore but i will see if i can get a pic or two of it.On that one was a collet chuck,three and four jaw chucks and one for soft jaws which you bored out to fit any dia of work,or and a face plate as well so you can clamp any shapes to.Allso had two fixed steady rests and a traveling one as well we used a lot to make long lead screws and shafts,i was a machinest for 20 odd years in the Toolroom.

 

[parrisw]

Nice work matt, but one thing, it looks like the sides of the pop-up are square. If so they shouldn't be, it disrupts flow across the piston, I set my cross slide to 60° and taper the pop-up sides.

 

[MCW]

Nice work matt, but one thing, it looks like the sides of the pop-up are square. If so they shouldn't be, it disrupts flow across the piston, I set my cross slide to 60° and taper the pop-up sides.

Hi Will.
In the photo it does seem hard to tell but yes the sides of the pop up are tapered. It runs a treat - gave it a run tonight again after work.

 

[gmax]

Matt, have you done a compression check since installing the popup?

 

[MCW]

Matt, have you done a compression check since installing the popup?

No not yet Wayne. I'll get onto it soon as have Thursday and Friday off so will spend 4 days cutting May even have time for a compression check somewhere in the middle as I plan on using the XPG.

 

[parrisw]

Hi Will.
In the photo it does seem hard to tell but yes the sides of the pop up are tapered. It runs a treat - gave it a run tonight again after work.

Sweet! From the pic it did look square. Sorry anyway, carry on!

I've done some machine work for a guy on a few 390's, and I know one of them came in with some pretty stout compression, I went a little more on the popup at .035, and he said it was around 190psi.

 

[FATGUY]

As mentioned earlier I pulled the lid on my modded 390XPG to have a look at what I could do in regard to increasing compression after deciding to sell the 660 and keep this saw. In the process I luckily found a split intake boot so got Brad to order me a new one from the states (thanks Brad ). Anyway, I wrecked the base gasket and thought "Ah well, I'll run it without one".
Unfortunately what I found by doing this was NO squish. The saw could turn over but the piston was "just" tapping the squish band. I finally found enough time yesterday to make it over to my mum and dad's place and sort out a .020" pop up on dad's lathe. Unfortunately his lathe chucks weren't quite deep enough to allow the jaws to fully grab a solid part of the piston. He has an old Hercus lathe from just after WW II.
A winegrape grower that I do work for has a fair setup in his shed (lathe, mill etc) and is an extremely handy and cluey guy when it comes to machining. I rang him this morning and as it was raining here he was doing some work in his shed anyway so he said he'd do it straight away. It took him about 15 minutes, if that. He didn't charge me either! He appreciates my help with Agronomic advice he said - greatly appreciated.
We were aiming for a .020" popup but ended up with a .019" popup - still OK...just

He was also extremely keen to know why the hell I was doing it! I had to talk modded saws for a moment and think I lost him

The most interesting thing was his lathe which I'd seen before but never taken much notice of. It is a solid piece of German equipment and was built in 1956. It's been refurbished though but it very accurate. Over a 600mm shaft he made there was only .00025" runout according to his Mitutoyo guages which isn't too bad in my book

Guys like Nik and other machinists here will probably feel all warm and fuzzy seeing a unit like this still at work - only 4 were ever brought into Australia...

Despite the current digital and electronic age this thing has all the bell's and whistles on it.

When I got home from work I fitted the piston and top end all back together and started the saw - I haven't touched the tune for now but the throttle response is completely different to before and it's noticably harder to pull over. I'm yet to check the compression but it was previously pulling about 150-155psi and I'd hope to see in excess of 180psi now but not sure what to expect. I also went out the shed and buried a 32" bar with 8 pin to the hilt in some very hard wood. It pulled it easily whereas previously it wouldn't have pulled it quite as well. Compression = torque in my book.

very nice work sir!

 

[MCW]

Sweet! From the pic it did look square. Sorry anyway, carry on!

I've done some machine work for a guy on a few 390's, and I know one of them came in with some pretty stout compression, I went a little more on the popup at .035, and he said it was around 190psi.

Hmmmmm. .035" you say Will? May have to pay my machining mate a visit again

very nice work sir!

Thanks Nik I'm sure you'd have spent some time on lathes like that over the years?

 

[parrisw]

Hmmmmm. .035" you say Will? May have to pay my machining mate a visit again



Thanks Nik I'm sure you'd have spent some time on lathes like that over the years?

Yep, that brings it slightly under the .100" crown though, and you'll have to machine the base.

 

[FATGUY]

Hmmmmm. .035" you say Will? May have to pay my machining mate a visit again



Thanks Nik I'm sure you'd have spent some time on lathes like that over the years?

Honestly, less than you might think. The vast majority of the work I do is CNC. I did more mork on manuals as an apprentice than as a journeyman.

 

[MCW]

Yep, that brings it slightly under the .100" crown though, and you'll have to machine the base.

Yeah that'd be right Will. I've been talking to Al, very helpful

Honestly, less than you might think. The vast majority of the work I do is CNC. I did more mork on manuals as an apprentice than as a journeyman.

Understandable mate. You've love this old German beast even more than I thought then

 

[parrisw]

Yeah that'd be right Will. I've been talking to Al, very helpful

GET-ER-DONE!

 

[MCW]

GET-ER-DONE!

On the cards mate Al just needs to find enough time to sit in his shed with his grinder and do some more aggressive port extensions for me! I can get the machining done at my end.

 

[AUSSIE1]

GET-ER-DONE!

Get into him Will!

On the cards mate Al just needs to find enough time to sit in his shed with his grinder and do some more aggressive port extensions for me! I can get the machining done at my end.

More aggressive port extensions? Hmmmmm I better do a little reading first Matt!

:msp_thumbup: