Porting tips for dummies

Totally normal JBOT /

Here's a few.

Add some of your own.

1. Get some magnifier glasses.

The detail is amazing and helps you cut right, you can really see all the imperfections.

2. Use 2t oil as cutting lube

3. Port outside in the sun and align yourself so the sun shines into the cylinder, makes for great views.

4. I use a leather welding apron and hold the cyl on my lap or on the table, catches all the pokey needle debris

5. Chamfer with a sandpaper wrapped chopstick

6. A small dremel wire brush shines up inside exhaust ports really fast, don't even have to sand much sometimes

Re: Porting tips for dummies

Magnifier Glasses whilst porting and needing a haircut

I’m one item away from being a mad scientist

Re: Porting tips for dummies

Good tips.

I'll have to try the wire wheel. I've been using these guys for finishing after using sanding drums. They are great because they get into corners well


I would add covering all sealing surfaces with heavy duty duct tape. I like the gorilla tape.

Also, foot controls are great to have and cost around $10. Makes everything so much easier

Re: Porting tips for dummies

Ľ̷̝̽͒i̶̛̼͑͠ȁ̸̧̛̽m̵̻̟̯̀̅ ̷͎̙̽̊F̶̲̺͑̓ F /

How do you clean up the rough finish from cutting with carbide? Grindstones just sort of wear away when used on cast iron, and gum up on aluminum

Re: Porting tips for dummies

> Ľ̷̝̽͒i̶̛̼͑͠ȁ̸̧̛̽m̵̻̟̯̀̅ ̷͎̙̽̊F̶̲̺͑̓ F Wrote:

> -------------------------------------------------------

> How do you clean up the rough finish from cutting with carbide?

> Grindstones just sort of wear away when used on cast iron, and gum up on

> aluminum

I always use the largest size cylindrical round nose burrs possible when removing a lot of material.

The finish will turn out a bit wavy but flat enough that sanding drums will smooth everything out fairly quickly.

After that I use the colored abrasive things and sandpaper to get the desired finish.

On cases I'll go up to 320 grit and exhaust port ducts up to 2000 grit.

The burrs that are tapered or the small diameter burrs put deep gouges so I only use those kind sparingly.

There is a 20pk of burrs on eBay that comes with the ten typical burrs and also ten small diameter ones that are great for sharp corners and such.

Re: Porting tips for dummies

EH 📣FCC of the QCB /

Mother’s Mag Polish

Forget polishing bars.....this stuff with cheep dremil polishing bits is the shit. Way easier to use and it yields quicker results. Be careful with over soaking the bit. Shit will go everywhere.

Also cheep Harbor Freight diamond Files are great for cleaning up ports. Pluss they have a lifetime warranty....like $8

I need to look into a welding apron. I hate getting metal in my shirt and all porcupined up.

Re: Porting tips for dummies

Sander Mulder /

another tip,

only polish the exhaust part, it isnt good to polish the transfers and inlet.

if you make the exhaust port wider, get an eye on where the piston ring gaps are going, you dont want those in your transfers or exhaust port.

you dont want sharp edges for the transfers, knife edging. 2strokestuffing on YouTube has an video explaining it.

and i highly recommend to watch more of his videos!

Re: Porting tips for dummies

♣Slew Foot♣ /

If you can find one. A magicians chromeball.

Its plastic but has a super strong magnet. It will stick to cylinder wall affording a port viewing angle to see the roof of the port as you work it.

Re: Porting tips for dummies

Kevin Bishop /

Use chalk to keep your bits from gumming up when cutting aluminum. Fuck oils they are messy and chalk is cheap af.

Re: Porting tips for dummies

Totally normal JBOT /

Oils are great

Where would you be without oils?

Nowhere that's where

Re: Porting tips for dummies

Buy one of these


I have one, i am on my second 90 degree head. You have to lube these things a lot or at least the cheap ones. like every hour or so of use. Sometimes less.. I have had these things uncomfortable to hold hot. It is so nice to use though and spins real fast which then lets you use....


These bad boys. I do all my roughing with carbide or big cut stuff then switch out to these for finishing. The amount of control you have is second to none and its easy to get a nice finish if you use the right technique plus they go really small so you can get real crisp corners on stuff

Finding the proper D latching bits is annoying, I usually just grind the D and then superglue it in, it just takes a tap to remove it.

Also if you are porting an aluminum nicasil bore, these are 100 times less likely to chip at the port edge as the carbide bur's grab and try to pull chunks off. These are much less grabby in that aspect.

to get that pro finish I use one of these and before I am completely done porting start going in one direction back in forth, usually from a corner to a corner, then change it up and go 45 degrees but keep the same back and forth pattern really tight on the last pass.

the reason for this in my experience It is really hard to get rid of the divots the tool can make in one direction, however if you then change the angle the tool cant "fall" into that divot without riding on the high section beside it which takes a little off that part, then you change angle and repeat again till you get the desired result.

You are basically doing a crosshatch. It makes it way easier for the tool to not follow the same patch and dig in every time.

I keep a can of WD-40 for cutter lube.

Layout dye is cheap and makes laying out ports easy and visuals always help with getting good results. On the cheap if you have a sharpie and and air compressor you can put the tip at the nozzle and spray sharpie to scribe as well. it's messy though.

Pick up some small riffler and round files for chamfering or even porting in odd areas.

PAINTERS TAPE THE COMPRESSION AREA SO YOU DON'T HAVE AN OOPSIE. We have all had a bur jump out of a port or the spinning collet rub against the cylinder and leave a little mark.. this just makes it so that is way harder.. do the sealing surface at the top of the head too.

I am not a pro but this is things i have picked up.


Re: Porting tips for dummies

What about “be brave” in terms of porting drunk or high

Re: Porting tips for dummies

> Pritza R&D Wrote:

> -------------------------------------------------------

> What about “be brave” in terms of porting drunk or high

That's fine , if you have the cash for a new cylinder . ;)

Re: Porting tips for dummies

Totally normal JBOT /

Always be high when porting.

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