Don't be like that. Painting the house in an unattractive and unplanned way along with other stupid things are what happens when I do sh*t without giving it even a second of though before doing it. I don't mind acknowledging these types lapses in my judgment but I just dont enjoy discussing them beyond that so I would prefer to return to engine building.
I found I didn't have a long enough boring bar to bore the guide hole...so I bored with an end mill. I left the holes .010" under the planned finish size incase threy move or pull during welding. I have to make the guides so I they don't have to be a round number... it's nice if they are but if things move more than the .010" I can make them whatever size the hole clean up at. I started boring for the new seats but I have a couple more cuts to make. Again I will leave them undersize but probably .020 or so since I have the seats I want to be certain the hole will clean up to size after welding. The new seats are 35mm, the valve 34mm so pretty close. I just don't want to go any bigger than I absolutely need to on the seats since I'm already changing the valve to valve spacing and going oversize it means cutting out a lot of metal on one side. It shoulf be fine though, the seat ID will be 29mm giving me a 3mm wall. I'm not sure how deep I want to set them exactly so I'm stopping at stock depth for the moment. I'll make a couple temp seats that I can play with for the flow work and get the vavle set where it works, then cut the final depth and dia to put the real seats in....that's the plan anyway. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Good Morning Mark, Glad to see your progress. Looking very nice. I had quite a hard time finding a reamer the proper size for my custom guide holes so I thought I'd send you this link. Didn't know if you were having the same. Reamers over .520" don't seem to be readily available but this place has them. I ordered one .525" and will finish ream my heads this weekend. www.eastonsupply.com Tom...
I think the reamer I need is the same one I use for injector ports so I have it but msc has them in .001 steps up to .700 along with common sizes (mm, number, fraction, ect) up over an inch. Mcmaster and enco also have a good selection including all the common sizes to over an inch.
Nice work Mark, The mill is a super tool, I know you know this, but I just have to say that they really really are!
I finished up the seat pockets on the first head. You can kind of see how much I sunk the intake valve when I was doing the development work, it's about 1.5mm.....so tonight I was second guessing myself and thinking I'd like to leave it a bit higher. The exhaust valves will sit lower to once the seats are cut to the right size....and maybe sunk a bit. The seat profile I'm using likes the valves to sit a bit lower than they would want to with a standard 3-angle seat. Image Unavailable, Please Login Image Unavailable, Please Login
Interesting idea, a milling cutter in a boring head. How accurate did the final holes turn out? From the pix I don't see any signs of tool chatter, was there any? Was looking at your milling setup, trying to figure out how I'd do it on my CNC mill. My mill head doesn't articulate, so decided I'd have to tilt the workpiece. Would probably make a big angle plate, either fixed or adjustable to mount the head to the mill bed. Hmm, I believe the cam caps and cam cover mounting surface are perpendicular to the valve stems, so maybe I could just make a flat plate that mounts against them & then mounts flat on the mill table. In fact this seems like the natural way to setup to machine valve seats, bore valve guide holes, etc, I'm wondering how you're mounting the head to your mill table. It looks like your cam cap surfaces are not at 90 degrees to the valve stems!
The Cam caps are not at 90 to the valves on the TR, QV, 2v, 360, or 400 heads and I assume the same is true about other models. The cap mount surface is parallel to the deck surface on evevy head I've ever seen or you need an agle plate of some kind. I've seen people do it a couple diferent ways. The strongest is a dedicated fixture with the angle milled right in. You just bolt it on the head, throw the head on the mill (normally aligning pins in the fixtur to hit the Tee slots) and start cutting. Usually the same fixture can have both the intake and exhaust angles cut on it. The way to save metal is to make 2 slotted fixtures to set the anlge and some kind of adapters to bolt them to the head so you grab cyl 1 with the first and cyl4 with the other, square it up on the table (again it could have alignment pins) then you you need to indicate the ange in and lock it, tghen you's ready to cut. The cuts we're talking about are very light so as long as you use at least 1/2" alum couple 1/2" bolts to lock each end it will work fine, it just takes more time to set up. As for the endmill in the boring head it's not prefered but it does work and will make a decent finish. You have to make sure that down at the end the the flute pointing the right way or yo can get some taper at the bottom of the hole...not a bit deal if its a through hole like I was working with. For the finish hole I'll bore with a boring bar from the other side so I can reach then probalby finish up with a reamer and maybe a light hone.
I plotted the cam lobes with the planned timing to get the top dead center lift number I will need for valve pockets in the pistons and also to get the lift point the valve cross at so I can check the valve to valve clearance. I need to know the valve to valve now so I know the valve seat height I pick actually works and doesnt crash the valve into each other ..its probably fine even with the big valves but I really need to measure it because it looks like thess cams have all 4 valves opened almost exactly .100" at the same time and the intake at opened about .130" when the piston is at TCT. Image Unavailable, Please Login
I didn't get a lot of time in the shop tonight so there is nothing pic worthy. Tomorow I'll have more time and should have the temp intake seats finished and be on to making templates and maybe grinding.
When I started talking about the temp seats who's job was it to point out that a V12 has 2 heads and I'd only cut the seats/guides in one of them? Luckily I realized before I tore down the set up so the temp seats are on hold and head 2 is under way but little one got bored so we had to come up stairs. It looks just like head 1 so I didn't bother with pics. I also realized that today is 5 weeks on the cams so in theory they are done now
And if it was Joe the Plumber,that 5 weeks = 5 months X 3 +..........ah who cares. At least you got them out of his hands and the ball is rolling now.
Is this particular cam order exceptionally difficult to fulfil? It seems like forever and a day that these cams have been on order and not yet arrived. All the best, Andrew.
I think deceptively difficult is a better description than exceptionally difficult but I think the hard part in now in the past. The first guy had great pricing and had masters for full race TR cams so he didnt see any problem as I was talking about a street engine so he was thinking worst case he gives me the race grind.. but I mentioned in a post some time back that the specs I am looking for require much more aggressive ramps on the cams than were used in full race TRs back in the day. This caused a lot of head scratching, test grinding and failing because he just didnt have anything in his master collection that would meet my specs on a cam over bucket engine and work with the Ferrari 24mm base circle. He could give me the lift if I took 20-30 degrees more or the duration if I gave up .050-.070 on the lift, so he gave up. At Web cam I knew they had a couple masters that were at least close so I move the cams to Web. They gave me 5-6 options, but only a couple good ones and all required test grinds because they had never tried them on the small Ferrari base circle. My first choices on both intake and exhaust couldnt be used because they produced a razor sharp nose on the lobe (this is the problem the first cam grinder kept running into), but luckily my second choices looked good. The whole delay was picking the lobes. Now that Im past that hurdle things are rolling but still a bit slow because billet steel cams require more steps than other cams and Web subs out a few or the step so there are lead times at multiple places to deal with along with the holidays. They should be getting close now.
That is a ton of steps indeed. I had no idea. No wonder it is impossible finding any other place besides megacycle and webcams to hard weld.
Just found this page. Is there a way to save it so I can view it later without trying to find it again?
