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How To: Spare Spark Plug Holder

July 28, 2011

A friend sent me a photo of a pre WWI Premier with a spare spark plug holder mounted on the seat tube of the frame.  And Dave Mac’s early Rudge had a nice one in an issue of The Classic Motorcycle a while ago too.  I’d always wanted one of these holders, but they don’t pop up on eBay or at swap meets.  So I decided to make one or two.  But the costs to make one or two are the same as making 30, so I sand cast 30 of them.   If you want to buy one or two, send me a note via the Comment link at the end of the article.

 

They are for sale for $15 each for the raw, un-machined part.  That is about 1 pound of brass for you to machine and finish.  Shipping is at cost, I’m not doing this to make money.

 

I don’t want to machine and polish 30 of these things, it would take me forever and I’d get a few dollars per hour for my labor.  Do it yourself, and have some fun!   Make it fit your frame size and your size of spark plug.  Several people pre-ordered parts via the OcchioLungo Facebook page a month or two ago, and the first shipments went out today.  There are a few more available, so send me a note via the Comments link if you are interested.

 

UPDATE AUGUST 1, 2011:  THERE HAS BEEN A GREAT REPONSE TO THESE OVER THE WEEKEND, AND THE FIRST RUN OF 30 PARTS IS ALREADY SOLD OUT.  I’M MAKING A LIST OF BUYERS FOR ANOTHER ORDER, SO IF YOU WANT SOME, SEND A NOTE VIA THE COMMENTS LINK.  I’LL WAIT ABOUT 2 WEEKS TO GET ALL THE ORDERS, THEN HAVE THE FOUNDRY DO ANOTHER RUN OF PARTS.   FYI, IF YOU HAVE A VTWIN OR PARALLEL TWIN, YOU CAN USE TWO SPARK PLUG HOLDERS MOUNTED TO EACH OTHER WITHOUT THE TWO CLAMPS.

UPDATE APRIL 2015: THE FIRST AND SECOND BATCH OF HOLDERS SOLD OUT LONG AGO. I MAY DO A THIRD BATCH SOMEDAY. FEEL FREE TO LEAVE YOUR NAME IN THE COMMENTS IF YOU’D LIKE TO BE NOTIFIED OF A NEW BATCH.

Here is that Premier at the Pioneer Run.  Note the cool plug, and the super cool fuel filter.  I think that this plug holder is polished aluminum.

spark plug holder

 

This is a different plug holder in plated brass has some neat scallops on the bottom side, and shows a bit of the details of how the part is made and how it attaches to the frame.  This one is mounted on the frame front downtube, the front wheel is on the left side of the photo.

sparkplug holder

 

Now, to make up my own part…

Step one was to design it in Solidworks CAD software.  It is something that I do as part of my day job, so it didn’t take any time at all.  I wanted the part to have the look of an acorn, so I added some scallops around the top, and a pointed tip at the bottom.  For sand casting, it has 3 degrees of draft all around, and can be pulled from the top surface with simple tooling.

casting 1 py-2

After machining, it will look like this.  There is one big hole to drill to fit the frame (this one will go up to 1.125” or so).  And a hole drilled and tapped for the spark plug (up to 18mm) and two holes for the mounting screws (10-32, or maybe 1BA or 5mm).  Plus a cut down the middle and some deburring.casting 1 py-machined

Then I sent the CAD file to a 3D printer and made up 6 copies in red ABS plastic.  This took several hours to print, then to clean.  Why red?  Just because that material was already in the printer machine.  In this view you can see the sharp points on the bottom tips, plus the scallops.IMG_7371

Then to the local brass foundry, Terminal Brass & Aluminum Foundry in South San Francisco.  Founded in 1920, they know how to do sand casting.  They put the 6 patterns onto a board, added sprues and risers, then pounded sand into 5 copes and drags.  The next time they were pouring yellow brass they made  a few samples for me to inspect.  Soon after, we had 30 good parts on my shop floor.

IMG_8996

IMG_9006

I spent an hour machining this one in my workshop tonight.  Pretty simple stuff:  drill & tap, saw cut, etc.  It needs some good deburring and polishing, then maybe a coating of nickel plating.IMG_9020

Here it is mounted on my Premier, with a scrap AC plug.  Still no polishing or plating yet!IMG_9018

early plugs

49 Comments leave one →
  1. charlie stewart permalink
    July 28, 2011 11:00 pm

    Pete, I’ll take two.
    Nice to see you and the family at the Alturas tour.
    Charlie

    • July 29, 2011 8:10 am

      Hi Charlie. I’ll email you with details. I can bring them to the Minden ride if you like.

  2. July 29, 2011 6:36 am

    pete ,, nice job on the spark plug holders,, i would love two if they are still available,, hope all is well with you,,will you be going to davenport?

  3. July 29, 2011 7:39 am

    Way cool Pete!

  4. alan comfort permalink
    July 29, 2011 11:18 pm

    Pete, I will have have one of your plug holders please and thank you.I think that it will look good on the MSS. Send to:
    Alan Comfort
    snip
    Vancouver, BC

    Best Regards, Alan

    • July 30, 2011 9:05 am

      Alan, you and Mats are the first guys on the waiting list. If there are enough people that want these parts, I can have the foundry cast up another 30 in about 2 weeks. There are several people that reserved parts back in March, but I haven’t heard back from them. I’ll give them a week, if they don’t contact me, then you can get one.

  5. Mats Munklinde permalink
    July 30, 2011 12:29 am

    Hi Pete!
    I am impressed. Can you help me with two?
    I will likely not go to Minden or Davenport so you will have to send them.
    Mats
    Sweden

    • July 30, 2011 9:05 am

      Mats, you and Alan are the first guys on the waiting list. If there are enough people that want these parts, I can have the foundry cast up another 30 in about 2 weeks. There are several people that reserved parts back in March, but I haven’t heard back from them. I’ll give them a week, if they don’t contact me, then you can get one.

  6. Doug Stedman permalink
    July 30, 2011 6:45 pm

    Pete-

    These are great, i have always wanted one of these. I have always seen the dual plug holders on triumphs and wondered if there were such things as a single plug holder… Now there is! . I will take two when you get enough for an order.

  7. Kevin K. Grubb permalink
    July 31, 2011 5:28 pm

    Pete,

    What a great item for my 1913 Rudge Multi. Sign me up for two please!

    How do I arrange for payment and shipment?

    • July 31, 2011 8:43 pm

      Hi Kevin. We have sold out of the first 30 spark plug holders already. I’m putting together a list to make up a bunch more. It will probably be a month or so, I want to make sure to catch everybody who wants some in the second batch. I’ve added you on the list for two, and I’ll email you with details when the time comes. thank you for your patience!

      Pete

  8. Mark Saxlund permalink
    August 2, 2011 1:39 pm

    Pete, I would like to order three of the castings. Let me know via E-mail How and What you want me to do.

    —Mark— (tool hauler for Mike Vils last Cannonball)

    • August 2, 2011 7:58 pm

      Hi Mark. I’ve emailed you directly. We’ll do another run of 30 in a couple weeks and I’ll set aside 3 castings for you. I hope you are doing well, it was good to see you in King City.

  9. August 10, 2011 9:03 pm

    Pete, I’d also like one of these for my 36 MSS.
    Regards, Tim

  10. Anonymous permalink
    August 14, 2011 11:19 pm

    Pete, nice work done with these spark plug holders.
    Any chance for me in Norway to get hold of one pair?? Please e-mail me at sve***ger@nline.no!

    Kind regards
    Sverre
    AmericanMotorcyclesNorway

    • August 15, 2011 8:34 am

      I”ve added you to the list for 2 of the castings. It will be a few weeks, but I’ll email you when they are ready.

  11. August 15, 2011 3:44 am

    Pete, great work!
    Wouldnt mind getting on the list for a pair of those. I have one different on my 21 HD. I have no problem in doing all the filing and drilling myself as I had to do with my other one.

    Look forward to hear from you.
    Sverre
    http://AmericanMotorcyclesNorway.blogspot.com

  12. Steve Cole permalink
    August 16, 2011 12:20 pm

    Pete,

    I would like to get one of these for my 39 MAC. Very nice work! Please email me the details.

    Thanks
    Steve

    • August 17, 2011 12:29 pm

      Hi Steve. I’ll be ordering them from the foundry in a week or two. When I get them, I’ll send you a note to get your mailing address, payment details, etc.

  13. jim Gilfoyle permalink
    August 17, 2011 1:49 pm

    I sure like to get a couple of those plug holders to put on my Knuck.
    Are you going to be in Davenport.
    Jim

    • August 17, 2011 2:12 pm

      Hi Jim.

      I can’t drive out to Davenport, but I can mail you a couple of castings. They should be ready in about a month I’d guess. Depends on the foundry’s timing. When they come in, I’ll send you an email. take care, pete.

  14. jim Gilfoyle permalink
    August 17, 2011 4:00 pm

    That would be great, Pete, thanks.
    Jim

  15. Anonymous permalink
    August 17, 2011 4:35 pm

    Hi Pete,

    I would like one if any are left. It would look really good on my 1929 AJS. Don’t know if you remember me, I am in the Velo club.

    Regards,
    Bruce Farren

    • August 17, 2011 9:43 pm

      sure thing Bruce! We missed you at the Oregon rally. I hope you’re doing well. I’ll get in touch in a few weeks when the foundry makes up the batch of castings.

  16. Daniel Rubinger permalink
    August 22, 2011 4:33 pm

    Hello Pete,
    would like six plug holders. Can pay through Paypal and will ask to be send to a friend in California, USA. Best regards from cold Argentina, Daniel.

    • August 23, 2011 11:13 am

      Sounds great Daniel. I’ll email you when the parts are ready from the foundry.

  17. Fred Butler permalink
    August 29, 2011 2:49 pm

    I have been reading your posts for some time and really enjoy them. If I could find out about getting two of your plug holders for a 1919 Indian I am working on would be great. I’m not too techno-savvy so I don’t even know for sure how to post this. Hope this gets through.

    • August 29, 2011 3:03 pm

      Hi Fred. your comment came through, no trouble. I’ll be placing the order for more holders next week, so you’ll get two of them in about a month. They aren’t tough to machine, you’ll need a drill press and hacksaw and some understanding of that stuff. But if you are working on a 19 Indian, you probably already know that. take care. Pete

  18. November 19, 2011 12:54 pm

    The second batch of spark plug holders arrived from the foundry this week. I’ll email you to get your home addresses, and get them mailed out asap.

    regards,
    Pete

  19. Tony permalink
    January 26, 2012 2:24 pm

    Hi Pete, do you still have any for sale?
    will you ship to the UK?
    I’d need two for my Ironhead Sporty.
    Take care

    Tony

  20. br_knight69@hotmail.com permalink
    March 12, 2012 3:52 am

    Hi Pete,Are you still making spark plug holders? if yes could i order 1 in aluminium if not brass will be fine, let me know costs for shipping to uk,i can pay by paypal, are you at the pioneer run this year, i will be riding my 1914 James. regards Brian Knight

    • March 12, 2012 8:32 am

      Hi Brian. I’ve sold all of the second batch of spark plug holders. But if we get orders for another batch of 30 or so, I’ll be sure to make some for you. I can’t make it on the Pioneer Run this year, but I’ll have the 1913 Veloce done soon and ship it to England for the 2013 Pioneer Run. If you take some good photos, be sure to send them to me! Regards,
      Pete

  21. Bevars permalink
    April 2, 2012 12:25 pm

    Hi Pete – put me down for 4 if you get enough orders for another batch.

    Thanks
    Bevars

    • April 2, 2012 12:34 pm

      OK Bevars. I’m not sure if/when we’ll get enough orders. But if we can get more, the foundry will do another run for us.

  22. Bruce Williams permalink
    June 6, 2012 3:05 am

    Pete, I’d like to have 2 plug holders, one for the 09 Neckarsulm and one for the 15 Austro Omega Thanks, Bruce

    • June 6, 2012 8:28 am

      Hi Bruce. I don’t have any right now, but if and when we cast up another run, I’ll be sure to get you two of them.

  23. Roger Klopfenstein permalink
    July 26, 2012 5:58 pm

    Hi Pete..If you ever do another run of plug holders, would love to have two. For two
    1912 HD beltdrive singles, Thanks, Roger

    • July 26, 2012 6:04 pm

      sure thing Roger. There are a few requests now, maybe I’ll do another run in the fall. I haven’t done it due to the effort of it all, but they are neat little pieces…

      • Roger Klopfenstein permalink
        June 5, 2016 6:53 am

        Hi Pete…I received the two plug holders, thanks . Please send me info. on where to mail payment..

      • June 7, 2016 3:05 pm

        Hi Roger. I just emailed you my paypal info.

  24. Tito permalink
    September 15, 2012 12:43 am

    I would love a couple in brass for my 39 flathead 45″. Please put me down for a set if two on the next pour.

  25. Harleyzt permalink
    November 5, 2012 7:07 pm

    These are great! Please out me down for a set!

    • November 5, 2012 7:23 pm

      Hi Harleyzt. I’ve used up all the castings. But if I do another set next year, I’ll include some for you and send you an email.

  26. brad kenyon permalink
    April 8, 2015 5:08 pm

    Hi Pete. Id like a pair of your Plug Holder castings if/ when you have 2 pieces available. Thank you very much

    • April 9, 2015 9:40 am

      Hi Brad. I made a couple of runs of those castings a few years ago. I might do another run and will be sure to email you if/when the parts are ready.

  27. May 5, 2015 9:24 am

    I’ll buy 4. Hell, if you need 30 to make another batch, I’ll buy whatever doesn’t sell.

    • May 5, 2015 4:09 pm

      Thanks Justin! There are plenty of buyers, I just haven’t found time to get them made, and then spend the hours required to pack and ship them and collect the $$. Maybe it would be a good chore to give my kids?!🙂

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