Project Stumpbroke How I do it

[imagineero]

I know there's a bit of fear in posting a thread like this that you worry you're going to lose business. There's always some fear that if people can see what you do, they'd be able to do it themselves and wouldnt need you. It's like the old way that mason's used to cutain off the work area so that people couldn't see the work area of the master. I feel a little the same way myself as a tree climber when customers want to watch and video the way I trim their trees and ask lots of questions. But you forget that as an expert, things that are easy for you are difficult for others!

The real truth, is that mastery cant be learnt by observing, and is worth paying for. It's like the quote frmo one of the mods here on AS;

"Until it is demonstrated, one forgets the really great difference between the merely competent amateur and the very expert professional."

There's nothing about watching me climb a tree that will teach a layman how to climb a tree, let alone the knowledge of how to trim it and make cuts properly, or the cost of the equipment involved to do the work. For that reason, I give pretty freely of my knowledge because it lets customers see what they are paying for, and in most cases makes them realise it was worth the money. Giving them an understanding of what they are getting increases the chances they will get me back again or reccommend me to their friends. Otherwise, they'd be thinking I do just the same thing as what they do. Once they understand the difference between what they do, and what I do, they can see the value in it. They are only going to trim their trees once, when will they practice? How many trees do they need to do to be as good as I am? Then they learn of the thousands of dollars of investment needed for climbing equipment and saws....

As a layman when it comes to porting, I know there's no way that I'm ever going to port as good as a pro. For starters, I don't own a lathe, or any of the gear needed to do porting. Getting my saws worked on is a one time investment that pays back over the life of the saw, but if I got it wrong I'd be looking at $$. I own a dozen saws, but my business is tree work, not porting. I could probably hack my way through a port job, but getting that last little bit out of a saw is something that needs a guy who is familiar with the intimate workings of each saw which only comes with experience. Certainly something worth paying for! Still nice to see someone showing the details of a pro job though...

Shaun

 

[Mastermind]

I know there's a bit of fear in posting a thread like this that you worry you're going to lose business. There's always some fear that if people can see what you do, they'd be able to do it themselves and wouldnt need you. It's like the old way that mason's used to cutain off the work area so that people couldn't see the work area of the master. I feel a little the same way myself as a tree climber when customers want to watch and video the way I trim their trees and ask lots of questions. But you forget that as an expert, things that are easy for you are difficult for others!

The real truth, is that mastery cant be learnt by observing, and is worth paying for. It's like the quote frmo one of the mods here on AS;

"Until it is demonstrated, one forgets the really great difference between the merely competent amateur and the very expert professional."

There's nothing about watching me climb a tree that will teach a layman how to climb a tree, let alone the knowledge of how to trim it and make cuts properly, or the cost of the equipment involved to do the work. For that reason, I give pretty freely of my knowledge because it lets customers see what they are paying for, and in most cases makes them realise it was worth the money. Giving them an understanding of what they are getting increases the chances they will get me back again or reccommend me to their friends. Otherwise, they'd be thinking I do just the same thing as what they do. Once they understand the difference between what they do, and what I do, they can see the value in it. They are only going to trim their trees once, when will they practice? How many trees do they need to do to be as good as I am? Then they learn of the thousands of dollars of investment needed for climbing equipment and saws....

As a layman when it comes to porting, I know there's no way that I'm ever going to port as good as a pro. For starters, I don't own a lathe, or any of the gear needed to do porting. Getting my saws worked on is a one time investment that pays back over the life of the saw, but if I got it wrong I'd be looking at $$. I own a dozen saws, but my business is tree work, not porting. I could probably hack my way through a port job, but getting that last little bit out of a saw is something that needs a guy who is familiar with the intimate workings of each saw which only comes with experience. Certainly something worth paying for! Still nice to see someone showing the details of a pro job though...

Shaun

Good post.....

I've taken some heat in the past for "showing too much". Oh well..... :msp_sneaky:

I feel like just seeing is a lot different then doing.......without experience some knowledge is useless. What Stumpy is doing here is actually good for his business. It gives people confidence that he knows what he's doing.

 

[mweba]

I tend to use the 1/4" round tip the most. Find it easier to control and avoid "bounce"

 

[deye223]

Good post.....

without experience some knowledge is useless.

yes a little bit of knowledge is more dangerous than too much:crazy1:

 

[husqyfan]

Porting demonstration

This is a great thread, thanks for all the photos. I have a question: how does cutting a squish band differ from from just cutting the base of the jug? Given both instances you end up with .020 squish. Why is one way better?

 

[Hedgerow]

This is a great thread, thanks for all the photos. I have a question: how does cutting a squish band differ from from just cutting the base of the jug? Given both instances you end up with .020 squish. Why is one way better?

You can get the ports to open and close when you want to by cutting the squish band and base and dropping the jug down .050.
You can also make the squish band larger, more precise, and get your combustion chamber to the size desired...

 

[husqyfan]

Band cut

So is the squish band cut at an angle or is cut so it is parallel to the piston crown? I can see it being alot more precise than factory, that's for sure.

 

[Hedgerow]

So is the squish band cut at an angle or is cut so it is parallel to the piston crown? I can see it being alot more precise than factory, that's for sure.

Some cut flat and some cut a slight angle.

 

[bryanr2]

Good post.....

I've taken some heat in the past for "showing too much". Oh well..... :msp_sneaky:

I feel like just seeing is a lot different then doing.......without experience some knowledge is useless. What Stumpy is doing here is actually good for his business. It gives people confidence that he knows what he's doing.

Your threads are the reason you got all of my business. I work hard for what money I have, and I want to know what it is spent on. I dont care for the "secret builders" and they will never get any business from me. I think $250 is a reasonable price to pay for the experience that comes from an experienced builder. It is money well spent. I have no interest in taking a saw apart or learning to port- what I enjoy is running the hell out of them and gathering my firewood.

 

[JRHAWK9]

I think $250 is a reasonable price to pay for the experience that comes from an experienced builder.

I agree, I was lucky enough to have tree monkey within 2 hours of me....he has 20+ years experience in building

 

[Stumpys Customs]

I know there's a bit of fear in posting a thread like this that you worry you're going to lose business. There's always some fear that if people can see what you do, they'd be able to do it themselves and wouldnt need you. It's like the old way that mason's used to cutain off the work area so that people couldn't see the work area of the master. I feel a little the same way myself as a tree climber when customers want to watch and video the way I trim their trees and ask lots of questions. But you forget that as an expert, things that are easy for you are difficult for others!

The real truth, is that mastery cant be learnt by observing, and is worth paying for. It's like the quote frmo one of the mods here on AS;

"Until it is demonstrated, one forgets the really great difference between the merely competent amateur and the very expert professional."

There's nothing about watching me climb a tree that will teach a layman how to climb a tree, let alone the knowledge of how to trim it and make cuts properly, or the cost of the equipment involved to do the work. For that reason, I give pretty freely of my knowledge because it lets customers see what they are paying for, and in most cases makes them realise it was worth the money. Giving them an understanding of what they are getting increases the chances they will get me back again or reccommend me to their friends. Otherwise, they'd be thinking I do just the same thing as what they do. Once they understand the difference between what they do, and what I do, they can see the value in it. They are only going to trim their trees once, when will they practice? How many trees do they need to do to be as good as I am? Then they learn of the thousands of dollars of investment needed for climbing equipment and saws....

As a layman when it comes to porting, I know there's no way that I'm ever going to port as good as a pro. For starters, I don't own a lathe, or any of the gear needed to do porting. Getting my saws worked on is a one time investment that pays back over the life of the saw, but if I got it wrong I'd be looking at $$. I own a dozen saws, but my business is tree work, not porting. I could probably hack my way through a port job, but getting that last little bit out of a saw is something that needs a guy who is familiar with the intimate workings of each saw which only comes with experience. Certainly something worth paying for! Still nice to see someone showing the details of a pro job though...

Shaun

Very well put. I did ave some reservations on doing this, but figured it wouldn't hurt anything. If somebody thinks my work is good enough to copy then thats just another complement.
My main objective was to show that it can be done without a bunch of High dollar equipment. Nothing against anybody useing the "fancy" stuff.

Good post.....

I've taken some heat in the past for "showing too much". Oh well..... :msp_sneaky:

I feel like just seeing is a lot different then doing.......without experience some knowledge is useless. What Stumpy is doing here is actually good for his business. It gives people confidence that he knows what he's doing.

Thanks Randy, I've also been known to show to much, just not on the saws.

I tend to use the 1/4" round tip the most. Find it easier to control and avoid "bounce"

I'll be replacing the 5/16 with a 1/4 wen I need a new one.

This is a great thread, thanks for all the photos. I have a question: how does cutting a squish band differ from from just cutting the base of the jug? Given both instances you end up with .020 squish. Why is one way better?

It gives you a smaller combustion chamber wich will net you more compression tan just lowering the jug. I also have more room to set the port timing where I want it.

 

[Stumpys Customs]

What compression ratio do you bump these up to?

I haven't figured the actual ratio.
The last 046 I built was blowin 215psi after the first tank of fuel.

So is the squish band cut at an angle or is cut so it is parallel to the piston crown? I can see it being alot more precise than factory, that's for sure.

I cut mine flat.

 

[Stumpys Customs]

Somebody asked about how I use the piston to mark with.

 

[Roll Tide]

Good post.....

I've taken some heat in the past for "showing too much". Oh well..... :msp_sneaky:

I feel like just seeing is a lot different then doing.......without experience some knowledge is useless. What Stumpy is doing here is actually good for his business. It gives people confidence that he knows what he's doing.

You port saws now Randy ? If they are half as good as your ported pies then I'm sending you three

 

[Hedgerow]

Somebody asked about how I use the piston to mark with.

Aaahhh... I see you use the work saw collector method of modification... You're poking it with a stick a little...
But that's a lot fancier stick than Stephen uses...
:msp_thumbsup:

 

[Stumpys Customs]

I think I left off at the intake port. So the next thing I do is the lower transfers.
I used the same 5/16 bit for these too. I don't do any other finishing to them.

I use smaller bits on other saws that have the Quad Port setup.

 

[Nitroman]

So is the squish band cut at an angle or is cut so it is parallel to the piston crown? I can see it being alot more precise than factory, that's for sure.

There are two books that have been published on 2-stroke performance. Both were written in the '60s or '70's I believe, but the theories regarding the combustion chamber design and squish are perfectly applicable to today. They are expensive books, but well worth reading. I have both somewhere in storage. I wish I could remember title but with diligent searching on here you should be able to find them. If your search-fu is strong, you could also find on Google.

 

[Stumpys Customs]

Now to move onto the upper transfers. This cyl as the dual port tranfsers meaning that it has a total of two transfer ports, one on each side of the cyl. The quadport saw are a lil more tricky to get in there since the ports are smaller & there are 4 of them, two on each side.

I use a pencil grinder to work on them. These grinding stones seem to work the best for me.

I hold the grinder at a slight angle to work them over.

This takes practice to get it right, but the results are nice.

 

[Stumpys Customs]

Now that the ports are rouged in I use a 120grit flapper on the pencil grinder to go around the edges of the ports to smooth them up for the next step.

After I smooth them up I clean the cyl up & bolt it back onto the case to double check the timing #'s. I had to go a lil further with the transfers to get them right. This is why I don't bevel the edges yet.

 

[watsonr]

Where do you draw the vertical line to mark the edge of the piston skirt?

use the piston to draw the upper and lower line of the ports opening on top and bottom. Trace the opening onto the piston and then measure the distance from the left and right edge of the port to the edge of the skirt and then draw the vertical line using the measurement into the cylinder wall staying a minimum .100 from the edge....