Another build thread... JoshNZ

JoshNZ · August 09, 2019, 10:51:03 PM

Well this week has been a bit of a gong show really, no progress just finding and fixing dumb things.

I went to order bearings and pillows from an engineering company on Thursday. Had them on the bench and the price came to about $60 more than on their website I said surely you can do it for the website price, I'll give cash and walk away it's done. But nope, can't be done. So they put them away, I made an account, ordered, they got them out again, packaged them (free freight on them...) and I still haven't got them by the weekend... I can't really do much until I see how things lie with the shafts in place. Seems to be a blanket rule in NZ for these engineering companies to be massive assholes to any new face walking off the street.

Anyway...
I noticed the beam must have reared up slightly when I welded the gussets on the bearing tongues. Also figured this is what was binding the lead screw nuts, plus the old weld was so thick I couldn't get full size washers on the bottom bolts so there was enough reasons to cut the gussets and start again. Now it's dead level and looks a lot better.

I did weld up a box to go over the end of the beam, I hope there is enough support. I thought about welding in a length of flat bar in the last ~400mm of the beam and plug welding it's edges to add strength but looking at it I'm not sure it's necessary.

Again the cooling weld got the better of me, it is certainly my achilles heel. I shimmed it and welded it and waited that evening until I could pick it up with bare hands, it slipped on like a glove. The next morning was fairly cold and I could only get it on about half way. All the grinding and pounding I could throw at it didn't seem to fix it. I scratched my head for a while and ended up finding a pair of bolts that fit in it and backed nuts off them while jammed inside it to lever it open a bit. Re-tacked and it fit nicely. Nice little trick to remember.

Welded plate on the other end of the beam about the same size so heights match and will weld second plates which I'll tap for bearings when the blocks arrive. I'm thinking I will extend the plate out quite far from the beam and support it with a gusset, then fix the rear bearing in place with threads and mill slots for the front bearing. This will mean the wheels swing as you adjust tracking but I think fixable with tension. I'm a little worried the slotted holes in the pillow blocks won't be enough for tracking adjustment on their own?

4140 shaft arrived but again I want to wait on the bearings before I start them. Engine also arrived, I went with a 22hp V twin Sina which is a Loncin I think.

I took air box off to drain carb bowl etc and plumb fuel line when I went to put it back on I noticed one of these collars wasn't in the hole which prevent the bolt crushing the plastic...

Of course the only logical place it might have gone is down the intake... :'(
I swept the floors then turned the flippn shed upside-down looking for it. Crawled around the engine with a flash light looking in nooks and crannies, hoisted it 6ft in the air and did the same thing. Spent about 2 hours looking for something that may not even exist...

I turned another one on the lathe anyway and put it back together, pretty much welcoming the engine to chew itself to bits so at least I could find it but, it didn't. I got it started and running full noise up to temp, all that drama aside it is a honey of an engine I'm pretty happy with it.

Other than that added a few other nothing bits. Gusset+Skid plate to the trailer hitch and chain tensioner.

I clamped a bit of round bar and hung the wheel on it trying to figure out where my bottle jack should go (which does work on its side I've learned). It would be easy enough to put it under the beam and I'd lose 3" of cut at that point - would it matter given what I've got? Top of the beam won't work, and I think the back of the beam will add force trying to twist off the sleeve which is already what's trying to happen.

Once the plate/gusset go on I could weld a little arm that extends past the linear bearing and put the jack on the front of the beam which would be most ideal force wise, least ideal effort wise. Is it worth doing?

Next week should be a busy week I'll hopefully have running wheels with an engine mounted. Will get a blade ordered as soon as I know what the length is looking like

JEverettM · August 09, 2019, 11:01:00 PM

When you welded up the box to slide over the beam, how much did you shim between the beam and the plates? I was thinking of doing something similar, but don't know how much shim to include.

charles mann · August 09, 2019, 11:35:10 PM

Quote from: JEverettM on August 09, 2019, 11:01:00 PM
When you welded up the box to slide over the beam, how much did you shim between the beam and the plates? I was thinking of doing something similar, but don't know how much shim to include.

when i did my box, i used 3 layers of aluminum tape on 2 sides and after welding, that wasn't enough for me. as with josh, all the hammer blows wouldn't force it on, well, i take that back I'm sure i could hammered it till it went on, but i know it would been a booger getting it off, seeing as i still had to hammer it off and it was only half way on. try 3-4 3x5 index cards on 2 sides. the guy i got my plans from used 3 or 4, can't remember, i think (90%) 4, and he had about 0.020" of wobble in his. i used a sanding disk on a grinder and ended up with about 0.040" of wobble. I'm gonna fix that buy putting a layer of hysol epoxy on my beam on 2 sides and depending, maybe the other 2 sides if i still have to much wobble. the best part is, with a lil lube, that hysol is about as slick as owl poop on a hickory limb and it take a lot of sanding to get it off and lays in nice and thin, or thick, depending the end requirements. but at $90 a pint, I'm glad mine was "expired" as far as the company shelf life policy, but it still works.

JoshNZ · August 10, 2019, 01:02:36 AM

I used a bit of card I found ahha, not ideal. That was after a 10 minute look around. Something about .5mm on two sides would be ideal, on the shoulders not the hollow middles. It's less about clearance and more about which way it shrinks which welds you hit first last etc which I have no clue about really.

Crusarius · August 10, 2019, 10:29:49 AM

For spacers I always use a 1/2" grade 8 washer. Relatively consistent in size and it doesn't burn when you get to close. Plus you only need one to cover 2 sides.

I dunno about you but I always have some in stock

Looking good. you should work on short welds and alternate welding locations. that will minimize the heat twist that you are getting. Or if you can balance the welding by doing a short weld in one place then going and doing the same thing on the opposite side they will keep each other flat.

welding is alot more than just sticking 2 pieces of steel together. Especially when you need them to mate or slide.

JustinW_NZ · August 11, 2019, 04:17:10 AM

Build looks good!
What part of NZ you in Josh?
(Im in Nelson)

Cheers
Justin

JoshNZ · August 11, 2019, 06:55:12 AM

I know the theory, short welds and placing so their tension opposes etc it's just not always practical. Short welds never look good with stick it's hard to tie in seemlessly.

Tauranga here Justin.

Dana Stanley · August 11, 2019, 07:55:08 AM

Quote from: JoshNZ on August 11, 2019, 06:55:12 AM
I know the theory, short welds and placing so their tension opposes etc it's just not always practical. Short welds never look good with stick it's hard to tie in seamlessly.

Tauranga here Justin.

Hindsight is everything. If you were to do that weld again, you could put bar stock in between so when it freezes its restrained from shrinking. you would need a plan to get it out after like heat the bar stock then let it cool, or evenly heat the unit and remove it while hot. you could have also tried heating the plate opposite the weld side. Easier to analyze these issues than to anticipate a problem.

Crusarius · August 11, 2019, 02:08:42 PM

What also work is to heat a section then rapid cool it. that will cause the steel to pull. WOrks great for straightening driveshafts.

JoshNZ · August 18, 2019, 02:13:36 AM

Another slow week for me. Got called into work a couple of times and the bearings didn't arrive for 8 days >=(.

Anyway. I welded some plates one to the sleeve one to the other end of the beam. I'd bought some 12mm flat bar 180mm wide I got sick of scraping rust off that bit of scrap. I thought 180 would be wide enough but turns out not, so welded two together with a deep weld and machined the warp out of them.

Next did the shafts, started with a bit of 40mm 4140 and only had to go down to 38.1 for the bearing journals (1.5"). 38mm for the Wheels. Turned the pulley section to 30mm which was a number I picked out of my head.

They both came out really good which was a relief cause this was going to be easy for me to screw up! All finishing cuts so no chip breaking, I slashed the pad right off my thumb trying to pull strings clear of the last cut... Made the rest of the week pretty difficult.
Both went into the freezer and one slipped into bearing pairs well the next morning, the other I had to drive on and is never coming off but that shouldn't be a problem.

I added pads and gussets for the jack to sit on and push against. I've got a hydraulic gauge arriving in the mail next week I think I'll just be able to tap into the base somewhere, or the pump cavity.

I think I'll turn a little socket and weld it to the plate for the jack to press against and maybe cut a small cylinder of rubber engine mount to sit in there. Or I could leave an air bubble in the jack too, as long as it never completely closes (which it can't) it won't bleed it out. I tried this and it gives quite a soft spring effect. Any thoughts? It's quite bouncy if I stand on it.

I added rubber shims to the lifting nuts, has quietened it down a lot and enabled adjustment of alignment. If the lead screw is binding, a quarter turn on one bolt frees it, another quarter binds again. I can set it in the middle and it has freed things up considerably. I'm learning the process/order of things with setup, bearing position, bar levelling, screw torque, all have to happen in the right order as they all affect each other.

I got the wheels on and ran a bit of pallet strapping around them just to see how it looks, and I'll be able to cut and measure for a blade length. I sighted along the wheels before tightening up the pillow blocks and the band ran dead straight on the wheels straight off the bat which is pretty encouraging. Means my threads are in the ball park and probably there is some crowning effect working too.

Starting to look like a mill!

I will probably get started on the engine mount next. I measured an audio recording of it today and got 3790RPM at full speed. The only centrifugal clutch I can find for 25hp is 140mm diameter so looking at the Band calculator here, I'll need another pulley as big as the band wheel which will only get it down to 5470fpm on the blade. So I'll either need to get the drive pulley way way down and do a belt tensioning clutch, or run a jackshaft, or fork out for another big pulley... Again, any thoughts...?
One thought I had about direct driving is I'll have to hang the engine way off the back of the beam to get the pulleys to line up. Which might be ok it's hard to tell how everything balances now.

My belts only sit up about 1.5mm (1/16") of the pulley lip, is this ok or should I take them down a bit?

Crusarius · August 18, 2019, 09:07:28 AM

I have a 19 band wheel with a 14" drive pulley being driven by a 4" centrifugal clutch. My speeds seem perfect.

as foo the 1/16" as long as the blade does not contact the metal wheel your fine but I would not expect 1/16 to last long. A good hot day and some milling will probably push the belt deeper into the groove and could cause you problems. The belt on my wheels holds the blade at least 1/4" above the wheel lips.

btulloh · August 18, 2019, 09:20:11 AM

My belts ride about 1/16" above the pulleys when new. I wish it was a little more and I'd turn the pulleys down a little if I had a lathe with enough swing.

Brad_bb · August 18, 2019, 04:26:26 PM

Where did your design come from Josh? Maybe I missed that in a previous post?

JoshNZ · August 18, 2019, 05:57:44 PM

I don't really have a design it is sort of dribbling out of my head as I go, which might be obvious. Lots of looking around here.

It does mean I've run into the odd roadblock - one being that the saw wheels are going to contact the trailer wheels when bottomed out as it is. They're spare car wheels on it now, I think flipping the axle from under slung to over slung and putting 13" trailer rims on it will solve that.

I will take down the pulleys a little going on what you guys are saying. My lathe does have a gap I can remove but I would prefer not to if I can get away without. I was thinking I'll just setup a tool post next to the wheel installed on the sawmill and hit it with a flap disc lightly while spinning somehow. Someone on a crank or I have a geared electric motor there somewhere. Will wait until the pulleys are installed to do that.

Punching those numbers in crusarius you are bang on. Definitely helps to get that drive pulley size down. It will be about $150 minimum to get a clutch to NZ, makes the belt tensioning lever appealing.

JoshNZ · August 18, 2019, 06:00:50 PM

Maybe I will just go with a clutch, less mucking around. The best I can find in NZ is one for $140NZ/$90US. But it's 5.5" which means I'll need a 17" driven pulley or jackshaft (which I think would be cheaper).

Anyone know of a better deal..?

There is a used electric ride-on clutch for sale for $90 here maybe that's worth jumping on? No specs on it but ones like it say they are rated for 80ft-lbs which should do it? Edit: Actually it's a TG2000 for a lawn tractor. They're rated 105ft-lbs with a 1" bore or 125ft-lbs with a 1-1/8". The V-twin is 45NM@2600RPM that's only 33ft-lb the engine can produce. I'm not missing anything here am I? Seems a no brainer

Crusarius · August 19, 2019, 07:20:31 AM

Quote from: JoshNZ on August 18, 2019, 05:57:44 PMone being that the saw wheels are going to contact the trailer wheels when bottomed out as it is. They're spare car wheels on it now, I think flipping the axle from under slung to over slung and putting 13" trailer rims on it will solve that.

Mine has that same problem. I just make sure I jack up the trailer high enough to clear the tires. The first time I forget though its going to be epic

Quote from: JoshNZ on August 18, 2019, 05:57:44 PMPunching those numbers in crusarius you are bang on. Definitely helps to get that drive pulley size down. It will be about $150 minimum to get a clutch to NZ, makes the belt tensioning lever appealing.

My clutch cost 310 so your not doing so bad. But I also used a double belt clutch.

I like the centrifugal clutch. Never like hearing belts squeal when you engage them.

Brad_bb · August 19, 2019, 10:32:22 PM

Quote from: JoshNZ on August 18, 2019, 05:57:44 PMI don't really have a design it is sort of dribbling out of my head as I go, which might be obvious. Lots of looking around here.

I thought you might be using Matt Cremona's plans....

JoshNZ · August 20, 2019, 06:47:01 PM

I watched through his videos quite a while ago actually so I have probably had seeds planted no doubt but, but it's definitely a follow my nose project.

I modified the engine exhaust today, what do you guys think haha will be popular with the neighbours ;D

Just kidding... Going back to the start, I clamped the engine somewhere near where it would live and saw the muffler is going to max out the saw beam height at less than 800mm/31" cut. Less if I put runners on the bed. Probably wasn't a huge deal but I thought it was a waste since the width will be near 40".

As it was, the exhaust was going to be blasting into the operators face so another reason to change it. Now both engine exhaust and blade exhaust are out the same side away from operator.

Spent ages trying to imagine where the muffler could go. This side it would heat the oil cooler, other side it would block the dip stick and heat electronics, ontop it obstructs the throttle but that will have a cable anyway so it seemed the best place.

The engine doesn't have 'Made in China' written anywhere on it, but holy goodness the muffler is another story.

Mig wire still stuck to the beads, or gaps where the bead has missed the joint completely. One of the headers is sticking right through the exhaust flange so it can't seal on the head. And the whole thing leaks obviously, through 3-4 different holes in the seams. I think Loncin put this muffler on all their V-twin models so be warned, while the engine looks ok the mufflers must be boxes of sh*t!

I tried to salvage the original flanges but they were made of cheese and fill of weld, the holes weren't centred, etc etc... So started again from 12mm plate. I don't have a tube bender so went with the pie cut method after a quick youtube tutorial, and since it was going to be a fairly tight sweep I went up as big as I could in tube diameter before the stud nuts wouldn't fit. The old tube was 22mmID and the new is 27mmID so hopefully I haven't created a flow restriction.

Blasted all the joints, then flapped it back to roughly smooth, then lapped the flanges on a tile and some sandpaper. Only took about 5 minutes to remove all the marker pen showing weld distortion.

After this I clamped the muffler in space roughly where it should go and it was a matter of fit, grind, fit grind, until I made two pipes that joined the gap.

One good thing about the engine is it has threaded mounting holes everywhere, there are two on the other side of the engine that I'll take struts from which should form a nice solid triangle.

I'm not sure how long the muffler will last, it feels like a decent backfire would peel it open so maybe this isn't it's final shape anyway. I'll sandblast and paint once I find some heat paint.

JoshNZ · August 22, 2019, 08:29:48 AM

Finished the struts and put the shroud back on it today. Gave it a good ring out once I had the mount finished and the exhaust is melting the air box =/... Bit stumped as to what to do with that one.

I seem to be creating problems quicker than I'm solving them at the moment.

Crusarius · August 22, 2019, 09:21:03 AM

have a piece of 16 gauge stainless? Just make a quick heat shield for the air box. need about 1/2" gap or enough to get the cover off.

JoshNZ · August 25, 2019, 07:12:41 PM

I didn't have any stainless and I think if I'd left an adequate gap the airbox lid wouldn't have come off. I've gone a bit more funky. Been stuck at work last few days so not getting far.

How are clutches/pulleys secured to the engine shaft usually? I have a 1/4" keyway on both shaft and clutch and a thread in the end of the shaft, do I just turn collars for each side of the clutch and put a bolt with a big washer/head in the end of the crank?

Crusarius · August 25, 2019, 07:30:40 PM

if you got the right size clutch should just slide it right on with a key and then bolt into the crank with big washer.

JoshNZ · September 02, 2019, 04:22:41 AM

I guess I got the wrong one 'cause it didn't fit like that. I turned a little collar to hold it just proud of the end of the shaft then a big thick washer for the end. I may split the collar yet if I need to reposition the clutch on the shaft but it all looks to be lining up.

I got the muffler sealed up and gave it a good burn, seems to be right this time. Don't think it looks too out of place does it :-\

I welded a plate half way between the engine and drive wheel for a jackshaft. Put 25mm pillow blocks on it and turned a shaft with a keyway for it today. You can prob tell I'm getting bored with this rubbish I'm posting now, my plans have been foiled by the postman once again with the pulleys now 4 days late >:(.

The pulleys I ordered have just a casting hole so I'll need to bore and key them, I made this tool today with a bit of scrap and hope to cut the internal keyways on the mill or lathe the manual way, will see how it goes.

Also had some aluminium offcuts lying around which I decided would make good belt tensioners. Rather than sliding the engine or jackshaft or whatever I'll just stick these at the end of an arm on each belt and take up the slack. I haven't used aluminium before I wish I could make everything from it!

I wondered if anyone has ever made log clamps or back stops out of round bar rather than box section? I still have quite a bit of 35mm bar left and it's rusting and a bit of a nuisance. Is there any reason they have to be square/flat?

Crusarius · September 02, 2019, 08:53:32 AM

Quote from: JoshNZ on September 02, 2019, 04:22:41 AMI got the muffler sealed up and gave it a good burn, seems to be right this time. Don't think it looks too out of place does it

That looks mine. Eliminates alot of other issues. ONly things to worry about is height when sawframe is all the way up and I would definitely put a rain cap on that. Otherwise, first thing in the morning your going to get a very bad shower.

Quote from: JoshNZ on September 02, 2019, 04:22:41 AMI haven't used aluminium before I wish I could make everything from it!

Aluminum is a dream to work with compared to some of the tool steels I end up having to use or 430fr. Don't care much for that but always end up needing to use it.

Quote from: JoshNZ on September 02, 2019, 04:22:41 AMI wondered if anyone has ever made log clamps or back stops out of round bar rather than box section? I still have quite a bit of 35mm bar left and it's rusting and a bit of a nuisance. Is there any reason they have to be square/flat?

Only reason I used square is because the cost difference was almost 2:1 in favor of square. Round would be fine. The only thing I can think would be challenging with round is what you use for log clamps. For mine I used square and hinged an arm to flip up and contact the log. With round it is a hinge so you can avoid that step. The only thing you would need to do is make it lock in place to clamp the log. I am sure you can figure something out for it.

The round is not going to be as strong as a rectangular section would be but depending on where they are located and how long of a span they will work just fine.

The build is looking great. Keep up the good work.

JoshNZ · September 04, 2019, 05:46:05 AM

I'll keep scratching my head about that one. I have some 12mm plate left I may make it out of that and hinge it on the round bar.

The little key cutting tool worked a treat and jackshaft went together pretty well. I think I will leave the second belt with no tensioner and just slide the pillow blocks.

I've got 1015RPM on the drive wheel now so... 4900FPS. The governor can be adjusted either way still but I guess thats a starting point.

I really wish I'd left more room on the plates to add a tracking adjustment but there's no room between the pillow blocks and verticals of the frame for bolts in threads/nuts. Didn't see the big picture at the start unfortunately. I turned little bolts with eccentric heads then drilled holes beside the pillows. It works alright on the bench but we'll see.

Should the pillows/bolts hold their position with the band tension alone or will they definitely need support to stop from creeping along?