Ask an Engineer

[Ocean1]

I think one of the few places I found that had the donuts was in Welly. Likely the same guy.
There was a thread me and Grumph posted in about them but I can't recall where it was (it might even have been this one)
I think the thread was someone looking for stainless bends and MS donuts

Interesting story behind those donuts. The guy worked for Southwards, developed the procedure for making donuts there and tried to get them interested in making them commercially. They weren't interested, and several years later he started a business making them at home. He eventually progressed to a small workshop in Naenae, he's still there but while I think he's done OK out of them he's cartainly not there full time nowadays.

Don't think I've ever really needed stainless donuts, you can get pretty tight 90* and 180* bends off the shelf, made out Porirua way.

[husaberg]

Interesting story behind those donuts. The guy worked for Southwards, developed the procedure for making donuts there and tried to get them interested in making them commercially. They weren't interested, and several years later he started a business making them at home. He eventually progressed to a small workshop in Naenae, he's still there but while I think he's done OK out of them he's cartainly not there full time nowadays.

Don't think I've ever really needed stainless donuts, you can get pretty tight 90* and 180* bends off the shelf, made out Porirua way.

The dairy shed dudes have tight bends in SS in suitable sizes not sure of the grade though. I think it might be a bit brittle.
Pretty much the same thing happened with the guy that did the BSL (Bill Buckley)he used to work for a small government offshoot of the DSIR the government wasn't interested he brought them out and makes robots that make silicon chips and other precision stuff ands sends them all around the world.
Makes millions and spends it locally.

[Ocean1]

Stainless is for pussies, my Berg pipe is made of Inconel and Ti and CF hangers. I would hate to think what it cost.

So's the SDR. The 525 is stainless though. And I didn't make either, but if I was making one I'd uses stainless simply 'cause it's what I can get and it's what I've got experience with.

[Ocean1]

The dairy shed dudes have tight bends in SS in suitable sizes not sure of the grade though. I think it might be a bit brittle.

316. Most food grade process tube is, but you can get 304 in the same range of sizes/radii.

304 is less prone to work hardening, but you've still got to be a bit sensible with changes in cross section and with support.

[Madness]

Anyone know a good source for exhaust parts? off the shelf tube bends, weld flanges/fittings, mufflers (complete or as parts); one to do for the bike, one for the car.

http://www.chase.co.nz/

[bogan]

Cheers for the responses gentlemen.

Yeh bike will def be stainless, probly just 304. Not sure the exact design, but I've got CAD etc and can get tube lasering or mandrel bending done as required. It's more figuring out what standard bits are available to work with, cos you do not want to pay for lasering of the perforations :laugh:

For the car I might go with mild, probably should just ask on those forums, as I don't want something that ends up sounding like a boyracer shitbox... Will keep Segedins in mind spokes, but they have very little info posted on their muffler units.

[nzspokes]

Will keep Segedins in mind spokes, but they have very little info posted on their muffler units.

Yerp, the website is a bit shit but they have lots of bends for making headers etc. You cant make the muffler you want?

[Ocean1]

you do not want to pay for lasering of the perforations :laugh:

http://www.sandersonmachines.com/

[bogan]

Yerp, the website is a bit shit but they have lots of bends for making headers etc. You cant make the muffler you want?

Will do for the bike, can't really be arsed doing one for the car as well. Even just shit like SS O2 sensor weld nuts are proving tricky to find... Almost wish I'd got the $10 ones from the place I got my sensor gear.

[husaberg]

Cheers for the responses gentlemen.

Yeh bike will def be stainless, probly just 304. Not sure the exact design, but I've got CAD etc and can get tube lasering or mandrel bending done as required. It's more figuring out what standard bits are available to work with, cos you do not want to pay for lasering of the perforations :laugh:

For the car I might go with mild, probably should just ask on those forums, as I don't want something that ends up sounding like a boyracer shitbox... Will keep Segedins in mind spokes, but they have very little info posted on their muffler units.

Perforations...... have a look at this. (when I find it)
http://www.kiwibiker.co.nz/forums/album.php?albumid=4864&attachmentid=303865
Click on the pic to scroll through.

[Grumph]

I'm late to the party but for MS exhaust bits, Chase is the place now. Even got quite a range of sensor fittings from memory - but not SS.
Bogan - for your car, just buy a system from Chase, they have a pretty wide range premade.

[bogan]

Anyone know a good (cheap) place for custom cut glass? I'm looking to do a coffee table, 4 panes can just be sharp as fuck window glass or whatever, top pane should be thicker/toughened with 4 holes (preferably countersunk) and beveled/polished edges with radius'd corners...

[Grumph]

Anyone know a good (cheap) place for custom cut glass? I'm looking to do a coffee table, 4 panes can just be sharp as fuck window glass or whatever, top pane should be thicker/toughened with 4 holes (preferably countersunk) and beveled/polished edges with radius'd corners...

I'd look in the yellow pages for a splashback manufacturer. For interior use even for shelves I'd want better than window glass.

[Ocean1]

Anyone know a good (cheap) place for custom cut glass? I'm looking to do a coffee table, 4 panes can just be sharp as fuck window glass or whatever, top pane should be thicker/toughened with 4 holes (preferably countersunk) and beveled/polished edges with radius'd corners...

My glass making contacts are all gone mate.

Couple of things, though. Sharp edges are verboten, (stress risers) and any glass should be cross belt linished at a minimum.

Toughened glass is wonderful stuff, but it don't solve all the problems. The edges are still vulnerable to a sharp wack, and it still scratches just the same. Often it's not too flat as it gets a bit of roller wave from the furnace, (ask to see samples). And if it ever does break the tiny wee shards that fall out between the main fracture pattern end up in the carpet, and usually cut the pile off at ground level within a month or two. You can make all artistic like, and take the chance with exposed edges, or you can fit the glass into a rebated frame.

[MENTAL490]

I'll go first, I'm doing some single point spline broaching (into ali), and have to grind up the broach tool as the hole size is about 8mm (gear shifter shaft). What material is best to grind into shape, and what grinding procedures (cooling etc) are needed. Have got plenty of busted carbide and HSS cutters if either of those materials would be suitable?

HSS is best for cutting ali and if you need coolant kerosene is also the best for ali, keep your tools sharp as ali is very abrasive and pickup easy, i used to braise a carbide tiponto HSS then grind it sharp on a silicon carbide or diamond wheel.

[MENTAL490]

Anyone know a good (cheap) place for custom cut glass? I'm looking to do a coffee table, 4 panes can just be sharp as fuck window glass or whatever, top pane should be thicker/toughened with 4 holes (preferably countersunk) and beveled/polished edges with radius'd corners...

I have a friend semi retired here dvk who is great and works for beer lol

[MENTAL490]

Anyone know a good source for exhaust parts? off the shelf tube bends, weld flanges/fittings, mufflers (complete or as parts); one to do for the bike, one for the car.

steel and tube sell most bends but ill talk to the old man tomorrow to see where he got his doughnuts cos he used to own the exhaust shop here in dvk a few years back.

[MENTAL490]

Anyone know a good source for exhaust parts? off the shelf tube bends, weld flanges/fittings, mufflers (complete or as parts); one to do for the bike, one for the car.

just talked to the fossil he recond manawatu mufflers tremain ave for donuts

[MENTAL490]

Yep i'm with you now. Probably shitty suppliers that are machining to different tolerances. Are the differing parts being locally made? or are they chinese shit/good euro quality?
It doesn't take much to go from tight to sloppy on a parallel thread. My guess is that a CNC just spits them out and no one gives a damn.

As you can see in the previous photo's, the 'standard' dimensions allow for no clearance on the threads.



It cleans them up pretty well, but then again we only use the small taps. 1/4 and 1/8 for plugging off 12mm waterway galleries. Nothing big like 1-2inch.
I would expect most female threads above 1 1/2" would usually be turned in a lathe?

Your guys would be cutting their own male threads though wouldn't they?
Not that this makes any difference as the problem you are having is the "same shaft, sloppy in some holes but not others";)

most workshops in aussie use unc for bsw apart from 1/2 inch cos its 1tpi diff but the angle of the thread is diff to, the aussie solution heaps of thread tape lmao...
also npt is just a bit bigger than bsp another head ache. i think the worst thread ive ever come up against was bike thread which as on a 30s humber

[speights_bud]

most workshops in aussie use unc for bsw apart from 1/2 inch cos its 1tpi diff but the angle of the thread is diff to, the aussie solution heaps of thread tape lmao...

Yea we would always use 60deg tooling for Whitworth threads. Just too much expense/hassle to buy or modify tooling to 55deg. Just match up the desired TPI and go for t.

Unless it was quite a large & course thread, and even then I'd just make something up from HSS

[MENTAL490]

I'll give you two modern options to replace the leather.
Sealing washers which are a steel washer with nitrile bonded on. Seal Imports carry a range and probably other places too.
Or make up replacements from urethane. I made up a set for a vintage Triumph rocker box which had pissed oil for ever. Top end is dry but of course the bottom end is still incontinent.

these days theres also a great range of PTFE for almost any job

[MENTAL490]

Niksil and the others are i believe semi ceramic click the arrow Chrome is old school and not so good for 2 smokes.

god i remember my first roadbike kr250, they had the first of the cromefusion barrels that never wear.......yeah right it just falls off and cost a fortune to repair on apprentice wages, at least when i got the kr1 it went likea bat outa hell but a shit stand

[MENTAL490]

Cheers for the responses gentlemen.

Yeh bike will def be stainless, probly just 304.

Wouldnt 316 be a better option if your not turning it (btw I have a small workshop here, if you need anyting machined just holla ya not to far from me.)

[bogan]

I have a friend semi retired here dvk who is great and works for beer lol

Could be a goer, shall I pm you the design files to pass along?


Wouldnt 316 be a better option if your not turning it (btw I have a small workshop here, if you need anyting machined just holla ya not to far from me.)

Yeh good point, it's probably worth the extra cost/hassle of finding 316 parts/fittings in the long run. Got a small workshop over here too, cnc router, lathe, mig/tig; would like to get a mill, but don't really have the shed space.

[MENTAL490]

Could be a goer, shall I pm you the design files to pass along?



Yeh good point, it's probably worth the extra cost/hassle of finding 316 parts/fittings in the long run. Got a small workshop over here too, cnc router, lathe, mig/tig; would like to get a mill, but don't really have the shed space.


i picked up a mill from the welly hospital, hardly used great price, i was so stoked. email the drgs to qld.tsv.game@gmail.com
i find 316 seems to be easier to find that 303 or 304 im not sure about NZ tho

[MENTAL490]

i picked up a mill from the welly hospital, hardly used great price, i was so stoked. email the drgs to qld.tsv.game@gmail.com

if your making your own pipe i have some software that might help, got it when i was gonna join 2cr500 engines and need a tuned but quiet pipe

[Ocean1]

Wouldnt 316 be a better option if your not turning it


Yeh good point, it's probably worth the extra cost/hassle of finding 316 parts/fittings in the long run.

Work hardens. Stick with 304.

[speights_bud]

Work hardens. Stick with 304.


Wouldnt 316 be a better option if your not turning it (btw I have a small workshop here, if you need anyting machined just holla ya not to far from me.)

What does "not turning it" have to do with it? Can turn 316 easily....

I'm with Ocean1 on this, 316 work hardens, then more prone to stress fractures etc. 304 is fine and have never had any issues. Unless you are riding it through brine, tomato juice or blood I dont think you will need the extra corrosion resistance properties either....

[MENTAL490]

Work hardens. Stick with 304.

yes but only under high stress because of the copper added but it wares alot better and as long as you don stress the hell out of its or use it as a running surface its tough and extremely durable where as 304 is a brittle version of 303 and welds tends to stress fracture. I have worked with all 3 alot, the only reason i would use 304 was if it was being machined.

[husaberg]

Work hardens. Stick with 304.


What does "not turning it" have to do with it? Can turn 316 easily....

I'm with Ocean1 on this, 316 work hardens, then more prone to stress fractures etc. 304 is fine and have never had any issues. Unless you are riding it through brine, tomato juice or blood I dont think you will need the extra corrosion resistance properties either....


yes but only under high stress because of the copper added but it wares alot better and as long as you don stress the hell out of its or use it as a running surface its tough and extremely durable where as 304 is a brittle version of 303 and welds tends to stress fracture. I have worked with all 3 alot, the only reason i would use 304 was if it was being machined.

jeeze guys just use Inconel
That way your grandchildren will be able to appreciate your welding technique

ps whats the software Mental?

[MENTAL490]

Was doing my monthly raid on a friends scrap yard and spied what looks like an 80s xv1000 its only good for parts but most of the running gear is there, if no one gets back to me at qld.tsv.game@gmail.com it will go to crusher, suh a waste. so plz let me know if you know someone, it will cost the current scrap steel price per KG which is stuff all.

[MENTAL490]

jeeze guys just use Inconel
That way your grandchildren will be able to appreciate your welding technique

ps whats the software Mental?

i cant honestly remember, its on my lappy in the workshp and to lazy n beered to look now buy ill look tommorrow

[husaberg]

Was doing my monthly raid on a friends scrap yard and spied what looks like an 80s xv1000 its only good for parts but most of the running gear is there, if no one gets back to me at qld.tsv.game@gmail.com it will go to crusher, suh a waste. so plz let me know if you know someone, it will cost the current scrap steel price per KG which is stuff all.

Grumph has always wanted to do one.
He has some aflicition about them?
something about a modern cafe vincent
pretty sure i could get it to the south Island using a kb pass the parcel.


Conveyor Belt specialists in ChCh were one of the places I meant. The other was a little place round the corner from Mace eng who seem to have disappeared post quakes. Local to you i'm sure there's a conveyor belt place who can do vulcanising. Again, check your local yellow pages for rubber products places.
I've only just realised my favourite small outfit referred to above has gone. Bugger it - they did all sorts of little bits of rubber mounts. very useful.

[MENTAL490]

Grumph has always wanted to do one.
He has some aflicition about them?
something about a modern cafe vincent
pretty sure i could get it to the south Island using a kb pass the parcel.

its in really bad shape, ill try get a few picks when im there on monday

[MENTAL490]

Grumph has always wanted to do one.
He has some aflicition about them?
something about a modern cafe vincent
pretty sure i could get it to the south Island using a kb pass the parcel.

i can drop it of to the ferry in welly, im down there at least once a month

[husaberg]

its in really bad shape, ill try get a few picks when im there on monday

So is Grumph..........
Nah hes a clever buggar
I am sure he could get mainfreght to pick it up (joke)
odd thats he hasn't be online tonight

Pagging Grumph

[MENTAL490]

So is Grumph..........
Nah hes a clever buggar
I am sure he could get mainfreght to pick it up (joke)
odd thats he hasn't be online tonight

Pagging Grumph

ive never really used forums so i now a have a serious case of verbal diarrhea :laugh:

[MENTAL490]

I should put the engine into a kids quad and give it to my niece for christmas :devil2: I could just imaging the look on my sisters face (joke) :nono:

[Grumph]

Was doing my monthly raid on a friends scrap yard and spied what looks like an 80s xv1000 its only good for parts but most of the running gear is there, if no one gets back to me at qld.tsv.game@gmail.com it will go to crusher, suh a waste. so plz let me know if you know someone, it will cost the current scrap steel price per KG which is stuff all.

Sold mine as it was never going to get finished. It's only worth something if it's the chain drive TR1 version. Shafties can go to the dump.
If it is the chain drive version, let Pete Sales in Palmy know it's there.

[MENTAL490]

No, angular clearance between the faces trailing the cutting edge and the cut profile. Sharpening a drill the face you grind needs the trailing edge to be clear of the cutting edge, yes? That angle should normally be 3-5 deg. Top rake for alloy should usually be quite high.



Cool. Shapers are almost a lost art. I did my time on a fckung massive planer, fond memories of making swarf 1/2" wide x 2 thou thick x 8 ft long.



That's actually a bit tempting...

a while back i repaired a gear tooth, built it up, ground most of with a grinder with a 1mm cut off (a bit naughty) then i finished it off with a digrinder straped to the lathe tool post.

[MENTAL490]

May have to use on of these in the next few months, scary, haven't been on something that since i was only a fitter. Its called a quartering lathe, very few still exist even fewer working.

http://img46.xooimage.com/files/0/5/e/wheel-lathe-7cb31e.jpg

This is the one we hope to use as its closer than the one at glenbrook.

http://whitetrout.net/nz/Jan03/Images/P1030140_e.jpg

[MENTAL490]

Sold mine as it was never going to get finished. It's only worth something if it's the chain drive TR1 version. Shafties can go to the dump.
If it is the chain drive version, let Pete Sales in Palmy know it's there.

Will do, I couldn't get a good look because i forgot my steel-caps, but im picking up a mower and an esky diff on monday so ill post a heap of pics for you.

[Grumph]

May have to use on of these in the next few months, scary, haven't been on something that since i was only a fitter. Its called a quartering lathe, very few still exist even fewer working.[/IMG]

This is the one we hope to use as its closer than the one at glenbrook.

Are the family into traction engines ?

If it's a crank repair, I'd have thought that provided a good center can be found, easier these days on a CNC as you can lay the wheel flat...

[MENTAL490]

Are the family into traction engines ?

If it's a crank repair, I'd have thought that provided a good center can be found, easier these days on a CNC as you can lay the wheel flat...

My dad is retired and spends alot of time doing thing for feilding steam rail, anyways the WAB they have, he crank pins are now under tollerance and flogged, i suggested a few cheap options but they want to do it by the book...meh

I even told them i could do it without even taking the axle out..shesh

[Grumph]

My dad is retired and spends alot of time doing thing for feilding steam rail, anyways the WAB they have, he crank pins are now under tollerance and flogged, i suggested a few cheap options but they want to do it by the book...meh

I even told them i could do it without even taking the axle out..shesh

Do they ever crack test anything ?

[guyhockley]

We moved back to the UK after 28 years abroad a while ago. For various reasons, incompatibility with british stuff, helping my son etc. I left a lot of gear behind, so almost starting from scratch. Currently (not really started) using a 3m square workshop attached to the house. Apparently, it's dashed bad form, what, to store acetylene in a residential area. Has anyone advice, experience, caveats to offer on using propane for bike frames (say; 3/4" or 19mm to 4"(!) 100mm x 16swg or 1,6mm steel), please?

(Also posted on the Chassis thread)

[Akzle]

only slightly lower temps with propane. it's all G.

[Ocean1]

We moved back to the UK after 28 years abroad a while ago. For various reasons, incompatibility with british stuff, helping my son etc. I left a lot of gear behind, so almost starting from scratch. Currently (not really started) using a 3m square workshop attached to the house. Apparently, it's dashed bad form, what, to store acetylene in a residential area. Has anyone advice, experience, caveats to offer on using propane for bike frames (say; 3/4" or 19mm to 4"(!) 100mm x 16swg or 1,6mm steel), please?

(Also posted on the Chassis thread)

I found just going up a tip size made up for the slightly cooler flame, worked fine.

Slight change in welding technique required but it didn't take long to nail it. Brazing light sections was more or less the same.

'Course, it's not a bad excuse for buying a wee TIG...

[HenryDorsetCase]

May have to use on of these in the next few months, scary, haven't been on something that since i was only a fitter. Its called a quartering lathe, very few still exist even fewer working.



whats the bit of wood for?

[eldog]

whats the bit of wood for?

intregued about operation, would be worth a look

nothing wrong with a good bit of slightly older machinery